initial commit

2019-07-14 20:37:26 +02:00 · 2019-07-14 20:37:26 +02:00 · cf40583989
commit cf40583989
118 changed files with 28228 additions and 0 deletions
--- a/.gitignore
+++ b/.gitignore
@ -0,0 +1,3 @@
+.vscode/
+node_modules/
+*.wat
--- a/benchmarking/.babelrc
+++ b/benchmarking/.babelrc
@ -0,0 +1,3 @@
+{
+    "presets": ["@babel/preset-react"]
+}
--- a/benchmarking/.prettierrc
+++ b/benchmarking/.prettierrc
@ -0,0 +1,4 @@
+{
+  "semi": false,
+  "singleQuote": true
+}
--- a/benchmarking/package-lock.json
+++ b/benchmarking/package-lock.json
--- a/benchmarking/package.json
+++ b/benchmarking/package.json
@ -0,0 +1,45 @@
+{
+  "name": "linestring-simplification",
+  "version": "0.1.0",
+  "description": "",
+  "main": "index.js",
+  "directories": {
+    "lib": "lib"
+  },
+  "scripts": {
+    "build": "webpack --mode development",
+    "serve": "webpack serve",
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "lint": "prettier --check '**/*.js'",
+    "format": "prettier --write '**/*.js'"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git@qgit.de:melch/linestring-simplification.git"
+  },
+  "author": "Alfred Melch (code@melch.pro)",
+  "license": "ISC",
+  "dependencies": {
+    "benchmark": "^2.1.4",
+    "chart.js": "^2.8.0",
+    "eslint-plugin-standard": "^4.0.0",
+    "lodash": "^4.17.11",
+    "react": "^16.8.6",
+    "react-chartjs-2": "^2.7.6",
+    "react-dom": "^16.8.6"
+  },
+  "devDependencies": {
+    "@babel/core": "^7.4.5",
+    "@babel/preset-react": "^7.0.0",
+    "@webpack-cli/serve": "^0.1.8",
+    "babel-loader": "^8.0.6",
+    "clean-webpack-plugin": "^3.0.0",
+    "copy-webpack-plugin": "^5.0.3",
+    "file-loader": "^4.0.0",
+    "prettier": "^1.18.2",
+    "react-hot-loader": "^4.12.0",
+    "webpack": "^4.34.0",
+    "webpack-cli": "^3.3.4",
+    "webpack-dev-server": "^3.7.1"
+  }
+}
--- a/benchmarking/public/index.html
+++ b/benchmarking/public/index.html
@ -0,0 +1,23 @@
+<html lang="en">
+
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <meta http-equiv="X-UA-Compatible" content="ie=edge">
+    <title>Document</title>
+    <link rel="stylesheet" href="./style.css">
+</head>
+
+<body>
+    <header>
+        <h1>Benchmarking</h1>
+    </header>
+    <main>
+        <div id="root"></div>
+    </main>
+
+
+    <script src="./bundle.js"></script>
+</body>
+
+</html>
--- a/benchmarking/public/style.css
+++ b/benchmarking/public/style.css
@ -0,0 +1,53 @@
+html,
+body {
+  font-family: Arial, Helvetica, sans-serif;
+  margin: 0;
+  padding: 0;
+}
+main {
+  width: 80%;
+  margin: 0 auto;
+}
+#status {
+  background-color: bisque;
+}
+form {
+  display: grid;
+  grid-template-columns: auto auto;
+  grid-gap: 10px;
+  align-items: center;
+  margin-top: 20px;
+}
+input[type="submit"] {
+  grid-column: 1 / -1;
+}
+
+#app {
+  display: flex;
+  flex-wrap: wrap;
+  border: 1px solid black;
+  justify-content: space-around;
+}
+
+#app > div {
+  margin: 10px 6px;
+  border: 1px solid red;
+}
+
+#form-component {
+  white-space: normal;
+}
+
+#chart-component {
+  width: 600px;
+}
+
+@media screen and (max-width: 800px) {
+  #app {
+    display: block;
+  }
+
+  #chart-component {
+    width: auto;
+  }
+}
--- a/benchmarking/src/benchmarkCases/Case.js
+++ b/benchmarking/src/benchmarkCases/Case.js
@ -0,0 +1,12 @@
+export class Case {
+  constructor(params) {
+    this.parameters = params
+  }
+
+  async fn() {
+    throw Error('No function to benchmark not implemented')
+  }
+
+  async setup() {}
+  async tearDown() {}
+}
--- a/benchmarking/src/benchmarkCases/index.js
+++ b/benchmarking/src/benchmarkCases/index.js
@ -0,0 +1,43 @@
+import { simplifyJSCase, origSimplifyJSCase } from './simplifyJS.js'
+import {
+  transformToArrayFormCase,
+  transformToObjectFormCase,
+  origSimplifyWithTransformCase
+} from './transforms.js'
+import {
+  simplifyWASMCase,
+  storeCoordsCase,
+  loadResultCase
+} from './simplifyWasm.js'
+
+export const chartDependencies = {
+  wasmStack: [storeCoordsCase, loadResultCase, simplifyWASMCase],
+  simplifyJSStack: [
+    origSimplifyWithTransformCase,
+    transformToArrayFormCase,
+    transformToObjectFormCase
+  ],
+  wasmVsJs: [origSimplifyJSCase, simplifyWASMCase, simplifyJSCase]
+}
+
+const uniqueFilter = (val, idx, self) => self.indexOf(val) === idx
+
+export function getChartDependencies(chartNames) {
+  return chartNames
+    .map(name => chartDependencies[name])
+    .flat()
+    .filter(uniqueFilter)
+}
+
+export function generateCases(data, formState) {
+  const cases = []
+  const { tolRange, highQual, chart } = formState
+  let params = { data, highQuality: highQual }
+  for (let tol of tolRange) {
+    params = { ...params, tol }
+    for (let BenchCaseClass of chartDependencies[chart]) {
+      cases.push(new BenchCaseClass(params))
+    }
+  }
+  return cases
+}
--- a/benchmarking/src/benchmarkCases/simplifyJS.js
+++ b/benchmarking/src/benchmarkCases/simplifyJS.js
@ -0,0 +1,33 @@
+import { Case } from './Case.js'
+
+import simplifyJS from '../../../lib/simplify-js-alternative/simplify.js'
+import origSimplifyJS from '../../../lib/turf-simplify/lib/simplify.js'
+
+function arrayToObjectFormat(coords) {
+  return coords.map(coord => {
+    return { x: coord[0], y: coord[1] }
+  })
+}
+
+export class simplifyJSCase extends Case {
+  get name() {
+    return 'simplifyJS'
+  }
+  async fn() {
+    const { data, tol, highQuality } = this.parameters
+    simplifyJS(data, tol, highQuality)
+  }
+}
+
+export class origSimplifyJSCase extends Case {
+  get name() {
+    return 'origSimplifyJS'
+  }
+  async setup() {
+    this.parameters.dataObjectForm = arrayToObjectFormat(this.parameters.data)
+  }
+  async fn() {
+    const { dataObjectForm, tol, highQuality } = this.parameters
+    origSimplifyJS(dataObjectForm, tol, highQuality)
+  }
+}
--- a/benchmarking/src/benchmarkCases/simplifyWasm.js
+++ b/benchmarking/src/benchmarkCases/simplifyWasm.js
@ -0,0 +1,59 @@
+import {
+  loadResult,
+  loadResultAndFreeMemory,
+  storeCoords
+} from '../../../lib/wasm-util/coordinates.js'
+import { simplifyWasm, getModule } from '../../../lib/simplify-wasm/index.js'
+
+import { Case } from './Case.js'
+
+export class simplifyWASMCase extends Case {
+  get name() {
+    return 'simplifyWASM'
+  }
+  async setup() {
+    this.parameters.module = await getModule()
+  }
+  async fn() {
+    const { data, tol, highQuality } = this.parameters
+    await simplifyWasm(data, tol, highQuality)
+  }
+}
+
+export class storeCoordsCase extends Case {
+  get name() {
+    return 'storeCoords'
+  }
+  async setup() {
+    this.parameters.module = await getModule()
+  }
+  async fn() {
+    const { module, data } = this.parameters
+    const buffer = storeCoords(module, data)
+    module._free(buffer)
+  }
+}
+
+export class loadResultCase extends Case {
+  get name() {
+    return 'loadResult'
+  }
+  async setup() {
+    const { data, tol, highQual } = this.parameters
+
+    const module = await getModule()
+    const buffer = storeCoords(module, data)
+    const result = module._simplify(buffer, data.length * 2, tol, highQual)
+    module._free(buffer)
+
+    this.parameters = { ...this.parameters, module, result }
+  }
+  async fn() {
+    const { module, result } = this.parameters
+    loadResult(module, result)
+  }
+  async tearDown() {
+    const { module, result } = this.parameters
+    loadResultAndFreeMemory(module, result)
+  }
+}
--- a/benchmarking/src/benchmarkCases/transforms.js
+++ b/benchmarking/src/benchmarkCases/transforms.js
@ -0,0 +1,47 @@
+import origSimplifyJS from '../../../lib/simplify-js/simplify.js'
+import { Case } from './Case.js'
+
+function arrayToObjectFormat(coords) {
+  return coords.map(coord => {
+    return { x: coord[0], y: coord[1] }
+  })
+}
+
+function objectToArrayFormat(coords) {
+  return coords.map(coord => [coord.x, coord.y])
+}
+
+export class transformToObjectFormCase extends Case {
+  get name() {
+    return 'transformToObjectFormCase'
+  }
+  async fn() {
+    arrayToObjectFormat(this.parameters.data)
+  }
+}
+
+export class transformToArrayFormCase extends Case {
+  get name() {
+    return 'transformToArrayFormCase'
+  }
+  async setup() {
+    const { data, tol, highQuality } = this.parameters
+    const transformed = arrayToObjectFormat(data)
+    this.parameters.simplified = origSimplifyJS(transformed, tol, highQuality)
+  }
+  async fn() {
+    objectToArrayFormat(this.parameters.simplified)
+  }
+}
+
+export class origSimplifyWithTransformCase extends Case {
+  get name() {
+    return 'origSimplifyWithTransformCase'
+  }
+  async fn() {
+    const { data, tol, highQuality } = this.parameters
+    const transformed = arrayToObjectFormat(data)
+    const simplified = origSimplifyJS(transformed, tol, highQuality)
+    objectToArrayFormat(simplified)
+  }
+}
--- a/benchmarking/src/benchmarks/Benchmark.js
+++ b/benchmarking/src/benchmarks/Benchmark.js
@ -0,0 +1,31 @@
+export class BenchmarkType {
+  /**
+   * Superclass for benchmarking a Case
+   * @param {object} parameters - Parameters for use in fn
+   * @param {object} functions - setup, fn and tearDown methods
+   */
+  constructor() {
+    this.stats = {}
+  }
+
+  setCase(benchmarkCase) {
+    this.case = benchmarkCase
+  }
+
+  /** Returns the mean time in milliseconds */
+  async run() {
+    let mean
+    if (typeof this.case === 'undefined') {
+      throw Error('no Benchmarking case set')
+    }
+    await this.case.setup()
+    mean = await this.measure()
+    await this.case.tearDown()
+    return mean
+  }
+
+  /** Implementation of the benchmarking procedure */
+  async measure() {
+    throw new Error('Method "measure" not implemented!')
+  }
+}
--- a/benchmarking/src/benchmarks/BenchmarkJSBenchmark.js
+++ b/benchmarking/src/benchmarks/BenchmarkJSBenchmark.js
@ -0,0 +1,40 @@
+import { Benchmark as BenchmarkJS } from './initBenchmarkJS.js'
+import { BenchmarkType } from './Benchmark.js'
+
+export class BenchmarkJSBenchmark extends BenchmarkType {
+  async measure() {
+    this.constructSuite()
+    await this.runSuite()
+    return this.mean
+  }
+
+  constructSuite() {
+    this.suite = new BenchmarkJS.Suite()
+    this.suite.add(this.case.name, {
+      defer: true,
+      fn: this.resolvingFn.bind(this)
+    })
+    this.suite.on('cycle', this.onCycle.bind(this))
+  }
+
+  async resolvingFn(deferred) {
+    await this.case.fn()
+    deferred.resolve()
+  }
+
+  onCycle(ev) {
+    this.mean = ev.target.stats.mean * 1000
+  }
+
+  async runSuite() {
+    const suitePromise = this.promisifySuite()
+    this.suite.run({ async: true })
+    await suitePromise
+  }
+
+  promisifySuite() {
+    return new Promise(resolve => {
+      this.suite.on('complete', resolve)
+    })
+  }
+}
--- a/benchmarking/src/benchmarks/BenchmarkSuite.js
+++ b/benchmarking/src/benchmarks/BenchmarkSuite.js
@ -0,0 +1,48 @@
+export class BenchmarkSuite {
+  constructor() {
+    this.reset()
+  }
+
+  reset() {
+    this.cases = []
+    this.stats = {}
+  }
+
+  setBenchmarkType(benchmarktype) {
+    this.benchmarktype = benchmarktype
+  }
+
+  setCases(cases) {
+    this.stats = {}
+    this.cases = cases
+    for (let c of this.cases) {
+      this.stats[c.name] = []
+    }
+  }
+
+  onCycle(i, count, stats) {}
+
+  async run(callback) {
+    let mean
+    let i = 0
+    const count = this.cases.length
+    this.onCycle(i, count, this.stats)
+    for (const benchCase of this.cases) {
+      this.benchmarktype.setCase(benchCase)
+      mean = await this.benchmarktype.run()
+      this.stats[benchCase.name] = [...this.stats[benchCase.name], mean]
+      i++
+      this.onCycle(i, count, this.stats)
+      await this.freeEventLoop()
+    }
+  }
+
+  /**
+   * Promise that uses setTimeout to resolve.
+   * This is a hack to free the eventloop from microtasks.
+   * Without this rendering blocks during benchmarks.
+   */
+  async freeEventLoop() {
+    return new Promise(resolve => setTimeout(resolve, 0))
+  }
+}
--- a/benchmarking/src/benchmarks/IterationBenchmark.js
+++ b/benchmarking/src/benchmarks/IterationBenchmark.js
@ -0,0 +1,17 @@
+import { BenchmarkType } from './Benchmark.js'
+
+export class IterationsBenchmark extends BenchmarkType {
+  constructor(iterations) {
+    super()
+    this.iterations = iterations
+  }
+
+  async measure() {
+    let start = performance.now()
+    for (let i = 0; i < this.iterations; i++) {
+      await this.case.fn()
+    }
+    let stop = performance.now()
+    return (stop - start) / this.iterations
+  }
+}
--- a/benchmarking/src/benchmarks/OpsPerTimeBenchmark.js
+++ b/benchmarking/src/benchmarks/OpsPerTimeBenchmark.js
@ -0,0 +1,19 @@
+import { BenchmarkType } from './Benchmark.js'
+
+export class OpsPerTimeBenchmark extends BenchmarkType {
+  constructor(timeToRun) {
+    super()
+    this.timeToRun = timeToRun
+  }
+
+  async measure() {
+    let start = performance.now()
+    let iterations = 0
+    while (performance.now() - start < this.timeToRun) {
+      iterations++
+      await this.case.fn()
+    }
+    let stop = performance.now()
+    return (stop - start) / iterations
+  }
+}
--- a/benchmarking/src/benchmarks/index.js
+++ b/benchmarking/src/benchmarks/index.js
@ -0,0 +1,9 @@
+import { IterationsBenchmark } from './IterationBenchmark'
+import { OpsPerTimeBenchmark } from './OpsPerTimeBenchmark'
+import { BenchmarkJSBenchmark } from './BenchmarkJSBenchmark'
+
+export const benchmarkTypes = {
+  benchmarkJS: BenchmarkJSBenchmark,
+  iteration: IterationsBenchmark,
+  opsPerTime: OpsPerTimeBenchmark
+}
--- a/benchmarking/src/benchmarks/initBenchmarkJS.js
+++ b/benchmarking/src/benchmarks/initBenchmarkJS.js
@ -0,0 +1,6 @@
+import _ from 'lodash'
+import process from 'process'
+
+const benchmark = require('benchmark')
+export const Benchmark = benchmark.runInContext({ _, process })
+window.Benchmark = Benchmark
--- a/benchmarking/src/components/chart.js
+++ b/benchmarking/src/components/chart.js
@ -0,0 +1,104 @@
+import React, { Component } from 'react'
+import { Line } from 'react-chartjs-2'
+
+import { data } from '../../../data/large.js'
+import simplifyJS from '../../../lib/simplify-js-alternative/simplify.js'
+
+export function simplifyMapper(labels, highQual) {
+  // console.log(labels, highQual)
+  // console.log(labels.map(tol => simplifyJS(data, tol, highQual)))
+  return labels.map(tol => simplifyJS(data, tol, highQual).length)
+}
+
+export class Chart extends Component {
+  constructor(props) {
+    super(props)
+    this.state = {
+      data: chartData,
+      options: chartOptions
+    }
+  }
+
+  render() {
+    let labels = this.props.labels.map(x => x.toFixed(3))
+    const data = { ...chartData, labels }
+    data.datasets[0].data = this.props.data['simplifyWASM'] || []
+    data.datasets[1].data = this.props.data['simplifyJS'] || []
+    data.datasets[2].data = this.props.data['origSimplifyJS'] || []
+    data.datasets[3].data = simplifyMapper(
+      this.props.labels,
+      this.props.highQual
+    )
+    return (
+      <div id="chart-component">
+        <h2>Chart</h2>
+        <Line
+          height={400}
+          width={600}
+          data={data}
+          options={this.state.options}
+        />
+      </div>
+    )
+  }
+}
+
+const chartData = {
+  datasets: [
+    {
+      label: 'simplifyWASM',
+      backgroundColor: 'red',
+      borderColor: 'red',
+      fill: false
+    },
+    {
+      label: 'simplifyJS',
+      backgroundColor: 'blue',
+      borderColor: 'blue',
+      fill: false
+    },
+    {
+      label: 'origSimplifyJS',
+      backgroundColor: 'green',
+      borderColor: 'green',
+      fill: false
+    },
+    {
+      label: 'numberOfNodes',
+      fill: false,
+      yAxisID: 'nodes',
+      data: [1, 2, 3]
+    }
+  ]
+}
+
+const chartOptions = {
+  title: {
+    display: true,
+    text: 'simplifyWasm VS simplifyJS'
+  },
+  tooltips: {
+    mode: 'index',
+    intersect: false
+  },
+  hover: {
+    mode: 'nearest',
+    intersect: false
+  },
+  scales: {
+    yAxes: [
+      {
+        id: 'performance',
+        type: 'linear'
+      },
+      {
+        id: 'nodes',
+        position: 'right',
+        type: 'linear',
+        gridLines: {
+          drawOnChartArea: false
+        }
+      }
+    ]
+  }
+}
--- a/benchmarking/src/components/form.js
+++ b/benchmarking/src/components/form.js
@ -0,0 +1,145 @@
+import React, { Component } from 'react'
+
+export class Form extends Component {
+  constructor(props) {
+    super(props)
+    this.state = {
+      tolStart: 0.1,
+      tolStep: 0.1,
+      tolEnd: 1,
+      highQual: true,
+      chart: 'wasmVsJs',
+      benchMethod: 'iteration',
+      iterations: 10,
+      timeToRun: 200
+    }
+
+    this.handleInputChange = this.handleInputChange.bind(this)
+    this.handleSubmit = this.handleSubmit.bind(this)
+    this.props.onFormChange(this.state)
+  }
+
+  handleSubmit(event) {
+    event.preventDefault()
+    this.props.onFormSubmit()
+  }
+
+  handleInputChange(event) {
+    let name, value
+    const target = event.target
+    value = target.type === 'checkbox' ? target.checked : target.value
+    value = target.type === 'number' ? Number(value) : value
+    value = target.type === 'range' ? Number(value) : value
+    name = target.name
+    this.setState({ [name]: value })
+    this.props.onFormChange({ ...this.state, [name]: value })
+  }
+
+  render() {
+    return (
+      <div id="form-component">
+        <h2>Settings</h2>
+        <form onSubmit={this.handleSubmit}>
+          <label>Tolerance start: </label>
+          <input
+            name="tolStart"
+            type="number"
+            min="0.001"
+            max="1"
+            step="0.001"
+            value={this.state.tolStart}
+            onChange={this.handleInputChange}
+          />
+
+          <label>Tolerance step: </label>
+          <input
+            name="tolStep"
+            type="number"
+            min="0.001"
+            max="1"
+            step="0.001"
+            value={this.state.tolStep}
+            onChange={this.handleInputChange}
+          />
+
+          <label>Tolerance end: </label>
+          <input
+            name="tolEnd"
+            type="number"
+            min="0.01"
+            max="5"
+            step="0.01"
+            value={this.state.tolEnd}
+            onChange={this.handleInputChange}
+          />
+
+          <label>high Quality: </label>
+          <input
+            name="highQual"
+            type="checkbox"
+            checked={this.state.highQual}
+            onChange={this.handleInputChange}
+          />
+
+          <label>Chart: </label>
+          <select
+            name="chart"
+            value={this.state.chart}
+            onChange={this.handleInputChange}
+          >
+            <option value="wasmVsJs">simplifyWasm vs. simplifyJS</option>
+            <option value="wasmStack">wasmStack</option>
+            <option value="simplifyStack">simplifyStack</option>
+          </select>
+
+          <label>Benchmarking method: </label>
+          <select
+            name="benchMethod"
+            value={this.state.benchMethod}
+            onChange={this.handleInputChange}
+          >
+            <option value="iteration">
+              Iterations (fast - low significance)
+            </option>
+            <option value="benchmarkJS">
+              BenchmarkJS (slow - statistically significant)
+            </option>
+            <option value="opsPerTime">
+              OpsPerTime (slow - low significance)
+            </option>
+          </select>
+          {this.state.benchMethod === 'iteration' && (
+            <label>Iterations ({this.state.iterations})</label>
+          )}
+          {this.state.benchMethod === 'iteration' && (
+            <input
+              name="iterations"
+              type="range"
+              min="1"
+              max="100"
+              step="1"
+              value={this.state.iterations}
+              onChange={this.handleInputChange}
+            ></input>
+          )}
+          {this.state.benchMethod === 'opsPerTime' && (
+            <label>Time to run ({this.state.timeToRun}ms)</label>
+          )}
+          {this.state.benchMethod === 'opsPerTime' && (
+            <input
+              name="timeToRun"
+              type="range"
+              min="100"
+              max="1000"
+              step="10"
+              value={this.state.timeToRun}
+              onChange={this.handleInputChange}
+            ></input>
+          )}
+
+          <input type="submit" value="run" />
+        </form>
+      </div>
+    )
+  }
+}
--- a/benchmarking/src/components/progress.js
+++ b/benchmarking/src/components/progress.js
@ -0,0 +1,14 @@
+import React from 'react'
+
+export const Progress = props => {
+  const { totalCount, finishedCount } = props
+  let percentage = totalCount === 0 ? 0 : (finishedCount * 100) / totalCount
+  percentage = percentage.toFixed(2)
+  let text = `${percentage}% of benchmarks completed (${finishedCount}/${totalCount})`
+  return (
+    <div id="progress-component">
+      <h2>Status</h2>
+      <span>{text}</span>
+    </div>
+  )
+}
--- a/benchmarking/src/index.js
+++ b/benchmarking/src/index.js
@ -0,0 +1,102 @@
+import React, { Component } from 'react'
+import ReactDOM from 'react-dom'
+
+import { data } from '../../data/large.js'
+
+import { Form } from './components/form.js'
+import { Chart } from './components/chart.js'
+import { Progress } from './components/progress.js'
+
+import { BenchmarkSuite } from './benchmarks/BenchmarkSuite.js'
+import { generateCases } from './benchmarkCases/index.js'
+import { IterationsBenchmark } from './benchmarks/IterationBenchmark.js'
+import { BenchmarkJSBenchmark } from './benchmarks/BenchmarkJSBenchmark.js'
+import { OpsPerTimeBenchmark } from './benchmarks/OpsPerTimeBenchmark.js'
+
+class App extends Component {
+  constructor(props) {
+    super(props)
+    this.handleformChange = this.handleformChange.bind(this)
+    this.handleFormSubmit = this.handleFormSubmit.bind(this)
+
+    this.state = {
+      stats: {},
+      formState: { tolRange: [] },
+      totalCount: 0,
+      finishedCount: 0
+    }
+
+    this.suite = new BenchmarkSuite(new IterationsBenchmark(10))
+    this.suite.onCycle = (i, count, stats) => {
+      this.setState({
+        finishedCount: i,
+        totalCount: count,
+        stats: stats
+      })
+    }
+  }
+
+  async handleFormSubmit() {
+    this.runBenchmarks()
+  }
+
+  handleformChange(formState) {
+    const { tolStart, tolEnd, tolStep } = formState
+    const tolRange = []
+    for (let i = tolStart; i < tolEnd; i += tolStep) {
+      tolRange.push(i)
+    }
+    this.setState({ formState: { ...formState, tolRange } })
+  }
+
+  async runBenchmarks() {
+    this.suite.reset()
+    let benchtype
+    console.log(this.state.formState.benchMethod)
+    switch (this.state.formState.benchMethod) {
+      case 'benchmarkJS':
+        benchtype = new BenchmarkJSBenchmark()
+        break
+      case 'iteration':
+        benchtype = new IterationsBenchmark(this.state.formState.iterations)
+        break
+      case 'opsPerTime':
+        benchtype = new OpsPerTimeBenchmark(this.state.formState.timeToRun)
+        break
+      default:
+        console.warn('benchmark type "' + this.state.benchtype + '" not known')
+        benchtype = new IterationsBenchmark(10)
+    }
+    this.suite.setBenchmarkType(benchtype)
+    this.suite.setCases(generateCases(data, this.state.formState))
+    updateStatus('Running')
+    await this.suite.run()
+    updateStatus('Finished')
+  }
+
+  render() {
+    return (
+      <div id="app">
+        <Form
+          onFormChange={this.handleformChange}
+          onFormSubmit={this.handleFormSubmit}
+        />
+        <Progress
+          totalCount={this.state.totalCount}
+          finishedCount={this.state.finishedCount}
+        />
+        <Chart
+          labels={this.state.formState.tolRange}
+          highQual={this.state.formState.highQual}
+          data={this.state.stats}
+        />
+      </div>
+    )
+  }
+}
+
+ReactDOM.render(<App />, document.getElementsByTagName('main')[0])
+
+const updateStatus = status => {
+  console.log(status)
+}
--- a/benchmarking/webpack.config.js
+++ b/benchmarking/webpack.config.js
@ -0,0 +1,40 @@
+const { CleanWebpackPlugin } = require('clean-webpack-plugin')
+const CopyPlugin = require('copy-webpack-plugin')
+const path = require('path')
+
+module.exports = {
+  entry: './src/index.js',
+  output: {
+    path: path.resolve(__dirname, 'dist'),
+    filename: 'bundle.js'
+  },
+  module: {
+    // Suppress warnings and errors logged by benchmark.js when bundled using webpack.
+    noParse: [path.resolve(__dirname, './node_modules/benchmark/benchmark.js')],
+    rules: [
+      {
+        test: /\.js$/,
+        loaders: ['babel-loader'],
+        exclude: [/node_modules/, /data/]
+      },
+      {
+        test: /\.wasm$/,
+        type: 'javascript/auto',
+        loader: 'file-loader',
+        options: {
+          name: '[name].[hash:5].[ext]'
+        }
+      }
+    ]
+  },
+  plugins: [new CleanWebpackPlugin(), new CopyPlugin([{ from: 'public' }])],
+  devtool: 'source-map',
+  // to make webpack work with emscripten js files
+  target: 'web',
+  node: {
+    __dirname: false,
+    fs: 'empty',
+    Buffer: false,
+    process: false
+  }
+}
--- a/data/large.js
+++ b/data/large.js
--- a/data/small.js
+++ b/data/small.js
@ -0,0 +1 @@
+export const data = [[0, 0], [1, 1], [1, 2], [2, 2], [5, 5], [5, 0], [6, 10], [10, 10]]
--- a/lib/psimpl/LICENSE.txt
+++ b/lib/psimpl/LICENSE.txt
@ -0,0 +1,470 @@
+                          MOZILLA PUBLIC LICENSE
+                                Version 1.1
+
+                              ---------------
+
+1. Definitions.
+
+     1.0.1. "Commercial Use" means distribution or otherwise making the
+     Covered Code available to a third party.
+
+     1.1. "Contributor" means each entity that creates or contributes to
+     the creation of Modifications.
+
+     1.2. "Contributor Version" means the combination of the Original
+     Code, prior Modifications used by a Contributor, and the Modifications
+     made by that particular Contributor.
+
+     1.3. "Covered Code" means the Original Code or Modifications or the
+     combination of the Original Code and Modifications, in each case
+     including portions thereof.
+
+     1.4. "Electronic Distribution Mechanism" means a mechanism generally
+     accepted in the software development community for the electronic
+     transfer of data.
+
+     1.5. "Executable" means Covered Code in any form other than Source
+     Code.
+
+     1.6. "Initial Developer" means the individual or entity identified
+     as the Initial Developer in the Source Code notice required by Exhibit
+     A.
+
+     1.7. "Larger Work" means a work which combines Covered Code or
+     portions thereof with code not governed by the terms of this License.
+
+     1.8. "License" means this document.
+
+     1.8.1. "Licensable" means having the right to grant, to the maximum
+     extent possible, whether at the time of the initial grant or
+     subsequently acquired, any and all of the rights conveyed herein.
+
+     1.9. "Modifications" means any addition to or deletion from the
+     substance or structure of either the Original Code or any previous
+     Modifications. When Covered Code is released as a series of files, a
+     Modification is:
+          A. Any addition to or deletion from the contents of a file
+          containing Original Code or previous Modifications.
+
+          B. Any new file that contains any part of the Original Code or
+          previous Modifications.
+
+     1.10. "Original Code" means Source Code of computer software code
+     which is described in the Source Code notice required by Exhibit A as
+     Original Code, and which, at the time of its release under this
+     License is not already Covered Code governed by this License.
+
+     1.10.1. "Patent Claims" means any patent claim(s), now owned or
+     hereafter acquired, including without limitation,  method, process,
+     and apparatus claims, in any patent Licensable by grantor.
+
+     1.11. "Source Code" means the preferred form of the Covered Code for
+     making modifications to it, including all modules it contains, plus
+     any associated interface definition files, scripts used to control
+     compilation and installation of an Executable, or source code
+     differential comparisons against either the Original Code or another
+     well known, available Covered Code of the Contributor's choice. The
+     Source Code can be in a compressed or archival form, provided the
+     appropriate decompression or de-archiving software is widely available
+     for no charge.
+
+     1.12. "You" (or "Your")  means an individual or a legal entity
+     exercising rights under, and complying with all of the terms of, this
+     License or a future version of this License issued under Section 6.1.
+     For legal entities, "You" includes any entity which controls, is
+     controlled by, or is under common control with You. For purposes of
+     this definition, "control" means (a) the power, direct or indirect,
+     to cause the direction or management of such entity, whether by
+     contract or otherwise, or (b) ownership of more than fifty percent
+     (50%) of the outstanding shares or beneficial ownership of such
+     entity.
+
+2. Source Code License.
+
+     2.1. The Initial Developer Grant.
+     The Initial Developer hereby grants You a world-wide, royalty-free,
+     non-exclusive license, subject to third party intellectual property
+     claims:
+          (a)  under intellectual property rights (other than patent or
+          trademark) Licensable by Initial Developer to use, reproduce,
+          modify, display, perform, sublicense and distribute the Original
+          Code (or portions thereof) with or without Modifications, and/or
+          as part of a Larger Work; and
+
+          (b) under Patents Claims infringed by the making, using or
+          selling of Original Code, to make, have made, use, practice,
+          sell, and offer for sale, and/or otherwise dispose of the
+          Original Code (or portions thereof).
+
+          (c) the licenses granted in this Section 2.1(a) and (b) are
+          effective on the date Initial Developer first distributes
+          Original Code under the terms of this License.
+
+          (d) Notwithstanding Section 2.1(b) above, no patent license is
+          granted: 1) for code that You delete from the Original Code; 2)
+          separate from the Original Code;  or 3) for infringements caused
+          by: i) the modification of the Original Code or ii) the
+          combination of the Original Code with other software or devices.
+
+     2.2. Contributor Grant.
+     Subject to third party intellectual property claims, each Contributor
+     hereby grants You a world-wide, royalty-free, non-exclusive license
+
+          (a)  under intellectual property rights (other than patent or
+          trademark) Licensable by Contributor, to use, reproduce, modify,
+          display, perform, sublicense and distribute the Modifications
+          created by such Contributor (or portions thereof) either on an
+          unmodified basis, with other Modifications, as Covered Code
+          and/or as part of a Larger Work; and
+
+          (b) under Patent Claims infringed by the making, using, or
+          selling of  Modifications made by that Contributor either alone
+          and/or in combination with its Contributor Version (or portions
+          of such combination), to make, use, sell, offer for sale, have
+          made, and/or otherwise dispose of: 1) Modifications made by that
+          Contributor (or portions thereof); and 2) the combination of
+          Modifications made by that Contributor with its Contributor
+          Version (or portions of such combination).
+
+          (c) the licenses granted in Sections 2.2(a) and 2.2(b) are
+          effective on the date Contributor first makes Commercial Use of
+          the Covered Code.
+
+          (d)    Notwithstanding Section 2.2(b) above, no patent license is
+          granted: 1) for any code that Contributor has deleted from the
+          Contributor Version; 2)  separate from the Contributor Version;
+          3)  for infringements caused by: i) third party modifications of
+          Contributor Version or ii)  the combination of Modifications made
+          by that Contributor with other software  (except as part of the
+          Contributor Version) or other devices; or 4) under Patent Claims
+          infringed by Covered Code in the absence of Modifications made by
+          that Contributor.
+
+3. Distribution Obligations.
+
+     3.1. Application of License.
+     The Modifications which You create or to which You contribute are
+     governed by the terms of this License, including without limitation
+     Section 2.2. The Source Code version of Covered Code may be
+     distributed only under the terms of this License or a future version
+     of this License released under Section 6.1, and You must include a
+     copy of this License with every copy of the Source Code You
+     distribute. You may not offer or impose any terms on any Source Code
+     version that alters or restricts the applicable version of this
+     License or the recipients' rights hereunder. However, You may include
+     an additional document offering the additional rights described in
+     Section 3.5.
+
+     3.2. Availability of Source Code.
+     Any Modification which You create or to which You contribute must be
+     made available in Source Code form under the terms of this License
+     either on the same media as an Executable version or via an accepted
+     Electronic Distribution Mechanism to anyone to whom you made an
+     Executable version available; and if made available via Electronic
+     Distribution Mechanism, must remain available for at least twelve (12)
+     months after the date it initially became available, or at least six
+     (6) months after a subsequent version of that particular Modification
+     has been made available to such recipients. You are responsible for
+     ensuring that the Source Code version remains available even if the
+     Electronic Distribution Mechanism is maintained by a third party.
+
+     3.3. Description of Modifications.
+     You must cause all Covered Code to which You contribute to contain a
+     file documenting the changes You made to create that Covered Code and
+     the date of any change. You must include a prominent statement that
+     the Modification is derived, directly or indirectly, from Original
+     Code provided by the Initial Developer and including the name of the
+     Initial Developer in (a) the Source Code, and (b) in any notice in an
+     Executable version or related documentation in which You describe the
+     origin or ownership of the Covered Code.
+
+     3.4. Intellectual Property Matters
+          (a) Third Party Claims.
+          If Contributor has knowledge that a license under a third party's
+          intellectual property rights is required to exercise the rights
+          granted by such Contributor under Sections 2.1 or 2.2,
+          Contributor must include a text file with the Source Code
+          distribution titled "LEGAL" which describes the claim and the
+          party making the claim in sufficient detail that a recipient will
+          know whom to contact. If Contributor obtains such knowledge after
+          the Modification is made available as described in Section 3.2,
+          Contributor shall promptly modify the LEGAL file in all copies
+          Contributor makes available thereafter and shall take other steps
+          (such as notifying appropriate mailing lists or newsgroups)
+          reasonably calculated to inform those who received the Covered
+          Code that new knowledge has been obtained.
+
+          (b) Contributor APIs.
+          If Contributor's Modifications include an application programming
+          interface and Contributor has knowledge of patent licenses which
+          are reasonably necessary to implement that API, Contributor must
+          also include this information in the LEGAL file.
+
+               (c)    Representations.
+          Contributor represents that, except as disclosed pursuant to
+          Section 3.4(a) above, Contributor believes that Contributor's
+          Modifications are Contributor's original creation(s) and/or
+          Contributor has sufficient rights to grant the rights conveyed by
+          this License.
+
+     3.5. Required Notices.
+     You must duplicate the notice in Exhibit A in each file of the Source
+     Code.  If it is not possible to put such notice in a particular Source
+     Code file due to its structure, then You must include such notice in a
+     location (such as a relevant directory) where a user would be likely
+     to look for such a notice.  If You created one or more Modification(s)
+     You may add your name as a Contributor to the notice described in
+     Exhibit A.  You must also duplicate this License in any documentation
+     for the Source Code where You describe recipients' rights or ownership
+     rights relating to Covered Code.  You may choose to offer, and to
+     charge a fee for, warranty, support, indemnity or liability
+     obligations to one or more recipients of Covered Code. However, You
+     may do so only on Your own behalf, and not on behalf of the Initial
+     Developer or any Contributor. You must make it absolutely clear than
+     any such warranty, support, indemnity or liability obligation is
+     offered by You alone, and You hereby agree to indemnify the Initial
+     Developer and every Contributor for any liability incurred by the
+     Initial Developer or such Contributor as a result of warranty,
+     support, indemnity or liability terms You offer.
+
+     3.6. Distribution of Executable Versions.
+     You may distribute Covered Code in Executable form only if the
+     requirements of Section 3.1-3.5 have been met for that Covered Code,
+     and if You include a notice stating that the Source Code version of
+     the Covered Code is available under the terms of this License,
+     including a description of how and where You have fulfilled the
+     obligations of Section 3.2. The notice must be conspicuously included
+     in any notice in an Executable version, related documentation or
+     collateral in which You describe recipients' rights relating to the
+     Covered Code. You may distribute the Executable version of Covered
+     Code or ownership rights under a license of Your choice, which may
+     contain terms different from this License, provided that You are in
+     compliance with the terms of this License and that the license for the
+     Executable version does not attempt to limit or alter the recipient's
+     rights in the Source Code version from the rights set forth in this
+     License. If You distribute the Executable version under a different
+     license You must make it absolutely clear that any terms which differ
+     from this License are offered by You alone, not by the Initial
+     Developer or any Contributor. You hereby agree to indemnify the
+     Initial Developer and every Contributor for any liability incurred by
+     the Initial Developer or such Contributor as a result of any such
+     terms You offer.
+
+     3.7. Larger Works.
+     You may create a Larger Work by combining Covered Code with other code
+     not governed by the terms of this License and distribute the Larger
+     Work as a single product. In such a case, You must make sure the
+     requirements of this License are fulfilled for the Covered Code.
+
+4. Inability to Comply Due to Statute or Regulation.
+
+     If it is impossible for You to comply with any of the terms of this
+     License with respect to some or all of the Covered Code due to
+     statute, judicial order, or regulation then You must: (a) comply with
+     the terms of this License to the maximum extent possible; and (b)
+     describe the limitations and the code they affect. Such description
+     must be included in the LEGAL file described in Section 3.4 and must
+     be included with all distributions of the Source Code. Except to the
+     extent prohibited by statute or regulation, such description must be
+     sufficiently detailed for a recipient of ordinary skill to be able to
+     understand it.
+
+5. Application of this License.
+
+     This License applies to code to which the Initial Developer has
+     attached the notice in Exhibit A and to related Covered Code.
+
+6. Versions of the License.
+
+     6.1. New Versions.
+     Netscape Communications Corporation ("Netscape") may publish revised
+     and/or new versions of the License from time to time. Each version
+     will be given a distinguishing version number.
+
+     6.2. Effect of New Versions.
+     Once Covered Code has been published under a particular version of the
+     License, You may always continue to use it under the terms of that
+     version. You may also choose to use such Covered Code under the terms
+     of any subsequent version of the License published by Netscape. No one
+     other than Netscape has the right to modify the terms applicable to
+     Covered Code created under this License.
+
+     6.3. Derivative Works.
+     If You create or use a modified version of this License (which you may
+     only do in order to apply it to code which is not already Covered Code
+     governed by this License), You must (a) rename Your license so that
+     the phrases "Mozilla", "MOZILLAPL", "MOZPL", "Netscape",
+     "MPL", "NPL" or any confusingly similar phrase do not appear in your
+     license (except to note that your license differs from this License)
+     and (b) otherwise make it clear that Your version of the license
+     contains terms which differ from the Mozilla Public License and
+     Netscape Public License. (Filling in the name of the Initial
+     Developer, Original Code or Contributor in the notice described in
+     Exhibit A shall not of themselves be deemed to be modifications of
+     this License.)
+
+7. DISCLAIMER OF WARRANTY.
+
+     COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS,
+     WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
+     WITHOUT LIMITATION, WARRANTIES THAT THE COVERED CODE IS FREE OF
+     DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE OR NON-INFRINGING.
+     THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED CODE
+     IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT,
+     YOU (NOT THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE
+     COST OF ANY NECESSARY SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER
+     OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE. NO USE OF
+     ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER THIS DISCLAIMER.
+
+8. TERMINATION.
+
+     8.1.  This License and the rights granted hereunder will terminate
+     automatically if You fail to comply with terms herein and fail to cure
+     such breach within 30 days of becoming aware of the breach. All
+     sublicenses to the Covered Code which are properly granted shall
+     survive any termination of this License. Provisions which, by their
+     nature, must remain in effect beyond the termination of this License
+     shall survive.
+
+     8.2.  If You initiate litigation by asserting a patent infringement
+     claim (excluding declatory judgment actions) against Initial Developer
+     or a Contributor (the Initial Developer or Contributor against whom
+     You file such action is referred to as "Participant")  alleging that:
+
+     (a)  such Participant's Contributor Version directly or indirectly
+     infringes any patent, then any and all rights granted by such
+     Participant to You under Sections 2.1 and/or 2.2 of this License
+     shall, upon 60 days notice from Participant terminate prospectively,
+     unless if within 60 days after receipt of notice You either: (i)
+     agree in writing to pay Participant a mutually agreeable reasonable
+     royalty for Your past and future use of Modifications made by such
+     Participant, or (ii) withdraw Your litigation claim with respect to
+     the Contributor Version against such Participant.  If within 60 days
+     of notice, a reasonable royalty and payment arrangement are not
+     mutually agreed upon in writing by the parties or the litigation claim
+     is not withdrawn, the rights granted by Participant to You under
+     Sections 2.1 and/or 2.2 automatically terminate at the expiration of
+     the 60 day notice period specified above.
+
+     (b)  any software, hardware, or device, other than such Participant's
+     Contributor Version, directly or indirectly infringes any patent, then
+     any rights granted to You by such Participant under Sections 2.1(b)
+     and 2.2(b) are revoked effective as of the date You first made, used,
+     sold, distributed, or had made, Modifications made by that
+     Participant.
+
+     8.3.  If You assert a patent infringement claim against Participant
+     alleging that such Participant's Contributor Version directly or
+     indirectly infringes any patent where such claim is resolved (such as
+     by license or settlement) prior to the initiation of patent
+     infringement litigation, then the reasonable value of the licenses
+     granted by such Participant under Sections 2.1 or 2.2 shall be taken
+     into account in determining the amount or value of any payment or
+     license.
+
+     8.4.  In the event of termination under Sections 8.1 or 8.2 above,
+     all end user license agreements (excluding distributors and resellers)
+     which have been validly granted by You or any distributor hereunder
+     prior to termination shall survive termination.
+
+9. LIMITATION OF LIABILITY.
+
+     UNDER NO CIRCUMSTANCES AND UNDER NO LEGAL THEORY, WHETHER TORT
+     (INCLUDING NEGLIGENCE), CONTRACT, OR OTHERWISE, SHALL YOU, THE INITIAL
+     DEVELOPER, ANY OTHER CONTRIBUTOR, OR ANY DISTRIBUTOR OF COVERED CODE,
+     OR ANY SUPPLIER OF ANY OF SUCH PARTIES, BE LIABLE TO ANY PERSON FOR
+     ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OF ANY
+     CHARACTER INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF GOODWILL,
+     WORK STOPPAGE, COMPUTER FAILURE OR MALFUNCTION, OR ANY AND ALL OTHER
+     COMMERCIAL DAMAGES OR LOSSES, EVEN IF SUCH PARTY SHALL HAVE BEEN
+     INFORMED OF THE POSSIBILITY OF SUCH DAMAGES. THIS LIMITATION OF
+     LIABILITY SHALL NOT APPLY TO LIABILITY FOR DEATH OR PERSONAL INJURY
+     RESULTING FROM SUCH PARTY'S NEGLIGENCE TO THE EXTENT APPLICABLE LAW
+     PROHIBITS SUCH LIMITATION. SOME JURISDICTIONS DO NOT ALLOW THE
+     EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO
+     THIS EXCLUSION AND LIMITATION MAY NOT APPLY TO YOU.
+
+10. U.S. GOVERNMENT END USERS.
+
+     The Covered Code is a "commercial item," as that term is defined in
+     48 C.F.R. 2.101 (Oct. 1995), consisting of "commercial computer
+     software" and "commercial computer software documentation," as such
+     terms are used in 48 C.F.R. 12.212 (Sept. 1995). Consistent with 48
+     C.F.R. 12.212 and 48 C.F.R. 227.7202-1 through 227.7202-4 (June 1995),
+     all U.S. Government End Users acquire Covered Code with only those
+     rights set forth herein.
+
+11. MISCELLANEOUS.
+
+     This License represents the complete agreement concerning subject
+     matter hereof. If any provision of this License is held to be
+     unenforceable, such provision shall be reformed only to the extent
+     necessary to make it enforceable. This License shall be governed by
+     California law provisions (except to the extent applicable law, if
+     any, provides otherwise), excluding its conflict-of-law provisions.
+     With respect to disputes in which at least one party is a citizen of,
+     or an entity chartered or registered to do business in the United
+     States of America, any litigation relating to this License shall be
+     subject to the jurisdiction of the Federal Courts of the Northern
+     District of California, with venue lying in Santa Clara County,
+     California, with the losing party responsible for costs, including
+     without limitation, court costs and reasonable attorneys' fees and
+     expenses. The application of the United Nations Convention on
+     Contracts for the International Sale of Goods is expressly excluded.
+     Any law or regulation which provides that the language of a contract
+     shall be construed against the drafter shall not apply to this
+     License.
+
+12. RESPONSIBILITY FOR CLAIMS.
+
+     As between Initial Developer and the Contributors, each party is
+     responsible for claims and damages arising, directly or indirectly,
+     out of its utilization of rights under this License and You agree to
+     work with Initial Developer and Contributors to distribute such
+     responsibility on an equitable basis. Nothing herein is intended or
+     shall be deemed to constitute any admission of liability.
+
+13. MULTIPLE-LICENSED CODE.
+
+     Initial Developer may designate portions of the Covered Code as
+     "Multiple-Licensed".  "Multiple-Licensed" means that the Initial
+     Developer permits you to utilize portions of the Covered Code under
+     Your choice of the NPL or the alternative licenses, if any, specified
+     by the Initial Developer in the file described in Exhibit A.
+
+EXHIBIT A -Mozilla Public License.
+
+     ``The contents of this file are subject to the Mozilla Public License
+     Version 1.1 (the "License"); you may not use this file except in
+     compliance with the License. You may obtain a copy of the License at
+     http://www.mozilla.org/MPL/
+
+     Software distributed under the License is distributed on an "AS IS"
+     basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
+     License for the specific language governing rights and limitations
+     under the License.
+
+     The Original Code is ______________________________________.
+
+     The Initial Developer of the Original Code is ________________________.
+     Portions created by ______________________ are Copyright (C) ______
+     _______________________. All Rights Reserved.
+
+     Contributor(s): ______________________________________.
+
+     Alternatively, the contents of this file may be used under the terms
+     of the _____ license (the  "[___] License"), in which case the
+     provisions of [______] License are applicable instead of those
+     above.  If you wish to allow use of your version of this file only
+     under the terms of the [____] License and not to allow others to use
+     your version of this file under the MPL, indicate your decision by
+     deleting  the provisions above and replace  them with the notice and
+     other provisions required by the [___] License.  If you do not delete
+     the provisions above, a recipient may use your version of this file
+     under either the MPL or the [___] License."
+
+     [NOTE: The text of this Exhibit A may differ slightly from the text of
+     the notices in the Source Code files of the Original Code. You should
+     use the text of this Exhibit A rather than the text found in the
+     Original Code Source Code for Your Modifications.]
+
--- a/lib/psimpl/README.txt
+++ b/lib/psimpl/README.txt
@ -0,0 +1,97 @@
+psimpl - generic n-dimensional polyline simplification
+Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+--------------------------------------------------------------------------------
+28-09-2010 - Initial version
+23-10-2010 - Changed license from CPOL to MPL
+26-10-2010 - Clarified input (type) requirements, and changed the
+             behavior of the algorithms under invalid input.
+01-12-2010 - Added the nth point, perpendicular distance and Reumann-Witkam
+             routines; moved all functions related to distance calculations to
+             the math namespace
+10-12-2010 - Fixed a bug in the perpendicular distance routine
+27-02-2011 - Added Opheim simplification, and functions for computing positional
+             errors due to simplification; renamed simplify_douglas_peucker_alt
+             to simplify_douglas_peucker_n
+18-06-2011   Added Lang simplification; fixed divide by zero bug when using
+             integers; fixed a bug where incorrect output iterators were
+             returned under invalid input; fixed a bug in douglas_peucker_n 
+             where an incorrect number of points could be returned; fixed a bug
+             in compute_positional_errors2 that required the output and input
+             iterator types to be the same; fixed a bug in
+             compute_positional_error_statistics where invalid statistics could
+             be returned under questionable input; documented input iterator
+             requirements for each algorithm; miscellaneous refactoring of most
+             algorithms.
+--------------------------------------------------------------------------------
+'psimpl' is licensed under the Mozilla Public License Version 1.1 (MPL), see
+the accompanying LICENSE.txt file. Alternatively a copy of this license may be
+obtained from http://www.mozilla.org/MPL/.
+--------------------------------------------------------------------------------
+'psimpl' is hosted at SourceForge: http://sourceforge.net/projects/psimpl/ and
+has a dedicated website: http://psimpl.sf.net
+Originally psimpl was released as part of the article 'Polyline Simplification'
+at The Code Project: 
+http://www.codeproject.com/KB/recipes/PolylineSimplification.aspx
+
+================================================================================
+
+'psimpl' is a c++ polyline simplification library that is generic, easy to use,
+and supports the following algorithms:
+
+Simplification
+* Nth point - A naive algorithm that keeps only each nth point
+* Distance between points - Removes successive points that are clustered
+  together
+* Perpendicular distance - Removes points based on their distance to the line
+  segment defined by their left and right neighbors
+* Reumann-Witkam - Shifts a strip along the polyline and removes points that
+  fall outside
+* Opheim - A constrained version of Reumann-Witkam
+* Lang - Similar to the Perpendicular distance routine, but instead of looking
+  only at direct neighbors, an entire search region is processed
+* Douglas-Peucker - A classic simplification algorithm that provides an
+  excellent approximation of the original line
+* A variation on the Douglas-Peucker algorithm - Slower, but yields better
+  results at lower resolutions
+
+Errors
+* positional error - Distance of each polyline point to its simplification
+
+All the algorithms have been implemented in a single standalone C++ header
+using an STL-style interface that operates on input and output iterators.
+Polylines can be of any dimension, and defined using floating point or signed
+integer data types.
+
+================================================================================
+
+The demo package contains a win32 demo application for 'psimpl'. The demo
+application allows you to experiment with the different simplification
+algorithms. It can generate pseudo random 2D-polylines of up to 10.000.000
+vertices in various types of containers. The boundingbox of the generated
+polyline is always 2n x n, where n is the amount of vertices of the generated
+polyline. Use this fact to specify a proper distance tolerance.
+
+Internally, the generated and simplified polyline are always stored in a
+QVector<double>. Just before simplification, it is converted to the selected
+container type. Afterwards, this temporary container is destructed. Normally you
+won't notice this, but it seems that creating and destructing a
+std::list(10.000.000) can take a rather long time. The resulting performance
+measurements never include these conversion steps. I chose this approach as it
+allowed me to quickly add new container types.
+
+Note that the entire application is single threaded (sorry for being lazy),
+meaning it could go 'not responding' during a long running simplification.
+
+The demo application was made using Qt 4.7.3, Qt Creator 2.1.0 and Visual Studio
+2008 Express. Complete source code is included.
+
+================================================================================
+
+If you decide to use my code for your (commercial) project, let me know! I would
+love to hear where my code ends up and why you chose to use it! If possible, a
+voluntary donation to my PayPal account (edekoning@gmail.com) would be much
+appreciated.
+
+Regards,
+Elmar de Koning
+edekoning@gmail.com
--- a/lib/psimpl/demo/DPWorker.cpp
+++ b/lib/psimpl/demo/DPWorker.cpp
@ -0,0 +1,782 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is
+ * 'psimpl - generic n-dimensional polyline simplification'.
+ *
+ * The Initial Developer of the Original Code is
+ * Elmar de Koning.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+    psimpl - generic n-dimensional polyline simplification
+    Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+
+    This file is part of psimpl, and is hosted at SourceForge:
+    http://sourceforge.net/projects/psimpl/
+*/
+
+#include "DPWorker.h"
+#include "psimpl_reference.h"
+#include "../lib/psimpl.h"
+#include <cmath>
+#include <QtCore/QTime>
+
+namespace psimpl {
+
+    DPWorker::DPWorker (QObject* inParent) :
+        QObject (inParent)
+    {
+        // note: disable this line during testing
+        srand ((unsigned)QTime::currentTime ().msec ());
+    }
+
+    void DPWorker::Generate (int inCount) {
+        emit SignalGeneratingPolyline ();
+
+        QTime t;
+        t.start ();
+
+        mGeneratedCoords.resize (inCount*2);
+        mSimplifiedCoords.clear ();
+
+        qreal miny = inCount;
+        qreal maxy = -inCount;
+
+        const qreal PI = std::atan (1.0) * 4;
+        qreal step = 2 * PI / inCount;
+
+        int a = 1 + (rand () % 2);    // [1, 3]
+        int b = 2 + (rand () % 3);    // [2, 5]
+        int c = 3 + (rand () % 7);    // [3, 10]
+
+        // generate a random line
+        for (int i=0; i<inCount; i++) {
+            mGeneratedCoords [i*2] = i;
+            qreal tmp1 = cos (step * i * a) / 3;
+            qreal tmp2 = sin (step * i * b) / 5;
+            qreal tmp3 = sin (step * i * c) / 10;
+            mGeneratedCoords [i*2+1] = tmp1 + tmp2 + tmp3;
+            miny = qMin (miny, mGeneratedCoords [i*2+1]);
+            maxy = qMax (maxy, mGeneratedCoords [i*2+1]);
+        }
+        // translate the line to (0,0) and scale the line to (2 * inCount, inCount)
+        qreal scaley = (inCount-1) / (maxy-miny);
+        for (int i=0; i<inCount; i++) {
+            mGeneratedCoords [i*2+1] = (mGeneratedCoords [i*2+1] - miny) * 0.5 * scaley;
+        }
+        //mGeneratedCoords.push_back(0);
+        emit SignalGeneratedPolyline (t.elapsed (), mGeneratedCoords);
+    }
+
+    void DPWorker::SimplifyNP (Container cont, int n) {
+        QTime t;
+        int duration = 0;
+
+        mSimplifiedCoords.clear ();
+
+        switch (cont) {
+        case ARRAY_FLOAT:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            float* generatedPoints = new float [mGeneratedCoords.size ()];
+            for (int c=0; c<mGeneratedCoords.size (); c++) {
+                generatedPoints [c] = mGeneratedCoords [c];
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            const float* begin = generatedPoints;
+            const float* end = generatedPoints + mGeneratedCoords.size ();
+            t.start ();
+            simplify_nth_point <2> (begin, end, n,
+                                    std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            // done
+            emit SignalCleaningConvertedPolyline ();
+            delete [] generatedPoints;
+            break;
+        }
+        case QVECTOR_DOUBLE:
+        {
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            QVector <qreal>::const_iterator begin = mGeneratedCoords.constBegin ();
+            QVector <qreal>::const_iterator end = mGeneratedCoords.constEnd ();
+            t.start ();
+            simplify_nth_point <2> (begin, end, n,
+                                    std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            break;
+        }
+        case VECTOR_DOUBLE:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::vector <double> generatedPoints = mGeneratedCoords.toStdVector ();
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::vector <double>::const_iterator begin = generatedPoints.begin ();
+            std::vector <double>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_nth_point <2> (begin, end, n,
+                                    std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        case LIST_LONGLONG:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::list <long long> generatedPoints;
+            foreach (double coord, mGeneratedCoords) {
+                generatedPoints.push_back (coord);
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::list <long long>::const_iterator begin = generatedPoints.begin ();
+            std::list <long long>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_nth_point <2> (begin, end, n,
+                                    std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        default:
+            break;
+        }
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::SimplifyRD (Container cont, QString tol) {
+        QTime t;
+        int duration = 0;
+
+        mSimplifiedCoords.clear ();
+
+        switch (cont) {
+        case ARRAY_FLOAT:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            float* generatedPoints = new float [mGeneratedCoords.size ()];
+            for (int c=0; c<mGeneratedCoords.size (); c++) {
+                generatedPoints [c] = mGeneratedCoords [c];
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            const float* begin = generatedPoints;
+            const float* end = generatedPoints + mGeneratedCoords.size ();
+            t.start ();
+            simplify_radial_distance <2> (begin, end, tol.toFloat(),
+                                          std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            // done
+            emit SignalCleaningConvertedPolyline ();
+            delete [] generatedPoints;
+            break;
+        }
+        case QVECTOR_DOUBLE:
+        {
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            QVector <qreal>::const_iterator begin = mGeneratedCoords.constBegin ();
+            QVector <qreal>::const_iterator end = mGeneratedCoords.constEnd ();
+            t.start ();
+            simplify_radial_distance <2> (begin, end, tol.toDouble (),
+                                          std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            break;
+        }
+        case VECTOR_DOUBLE:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::vector <double> generatedPoints = mGeneratedCoords.toStdVector ();
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::vector <double>::const_iterator begin = generatedPoints.begin ();
+            std::vector <double>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_radial_distance <2> (begin, end, tol.toDouble (),
+                                          std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        case LIST_LONGLONG:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::list <long long> generatedPoints;
+            foreach (double coord, mGeneratedCoords) {
+                generatedPoints.push_back (coord);
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::list <long long>::const_iterator begin = generatedPoints.begin ();
+            std::list <long long>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_radial_distance <2> (begin, end, tol.toLongLong (),
+                                          std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        default:
+            break;
+        }
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::SimplifyPD (Container cont, QString tol, int repeat) {
+        QTime t;
+        int duration = 0;
+
+        mSimplifiedCoords.clear ();
+
+        switch (cont) {
+        case ARRAY_FLOAT:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            float* generatedPoints = new float [mGeneratedCoords.size ()];
+            for (int c=0; c<mGeneratedCoords.size (); c++) {
+                generatedPoints [c] = mGeneratedCoords [c];
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            const float* begin = generatedPoints;
+            const float* end = generatedPoints + mGeneratedCoords.size ();
+            t.start ();
+            simplify_perpendicular_distance <2> (begin, end, tol.toFloat(), repeat,
+                                                 std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            // done
+            emit SignalCleaningConvertedPolyline ();
+            delete [] generatedPoints;
+            break;
+        }
+        case QVECTOR_DOUBLE:
+        {
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            QVector <qreal>::const_iterator begin = mGeneratedCoords.constBegin ();
+            QVector <qreal>::const_iterator end = mGeneratedCoords.constEnd ();
+            t.start ();
+            simplify_perpendicular_distance <2> (begin, end, tol.toDouble (), repeat,
+                                                 std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            break;
+        }
+        case VECTOR_DOUBLE:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::vector <double> generatedPoints = mGeneratedCoords.toStdVector ();
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::vector <double>::const_iterator begin = generatedPoints.begin ();
+            std::vector <double>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_perpendicular_distance <2> (begin, end, tol.toDouble (), repeat,
+                                                 std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        case LIST_LONGLONG:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::list <long long> generatedPoints;
+            foreach (double coord, mGeneratedCoords) {
+                generatedPoints.push_back (coord);
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::list <long long>::const_iterator begin = generatedPoints.begin ();
+            std::list <long long>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_perpendicular_distance <2> (begin, end, tol.toLongLong (), repeat,
+                                                 std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        default:
+            break;
+        }
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::SimplifyRW (Container cont, QString tol)
+    {
+        QTime t;
+        int duration = 0;
+
+        mSimplifiedCoords.clear ();
+
+        switch (cont) {
+        case ARRAY_FLOAT:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            float* generatedPoints = new float [mGeneratedCoords.size ()];
+            for (int c=0; c<mGeneratedCoords.size (); c++) {
+                generatedPoints [c] = mGeneratedCoords [c];
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            const float* begin = generatedPoints;
+            const float* end = generatedPoints + mGeneratedCoords.size ();
+            t.start ();
+            simplify_reumann_witkam <2> (begin, end, tol.toFloat(),
+                                         std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            // done
+            emit SignalCleaningConvertedPolyline ();
+            delete [] generatedPoints;
+            break;
+        }
+        case QVECTOR_DOUBLE:
+        {
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            QVector <qreal>::const_iterator begin = mGeneratedCoords.constBegin ();
+            QVector <qreal>::const_iterator end = mGeneratedCoords.constEnd ();
+            t.start ();
+            simplify_reumann_witkam <2> (begin, end, tol.toDouble (),
+                                         std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            break;
+        }
+        case VECTOR_DOUBLE:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::vector <double> generatedPoints = mGeneratedCoords.toStdVector ();
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::vector <double>::const_iterator begin = generatedPoints.begin ();
+            std::vector <double>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_reumann_witkam <2> (begin, end, tol.toDouble (),
+                                         std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        case LIST_LONGLONG:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::list <long long> generatedPoints;
+            foreach (double coord, mGeneratedCoords) {
+                generatedPoints.push_back (coord);
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::list <long long>::const_iterator begin = generatedPoints.begin ();
+            std::list <long long>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_reumann_witkam <2> (begin, end, tol.toLongLong (),
+                                         std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        default:
+            break;
+        }
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::SimplifyOp (Container cont, QString minTol, QString maxTol) {
+        QTime t;
+        int duration = 0;
+
+        mSimplifiedCoords.clear ();
+
+        switch (cont) {
+        case ARRAY_FLOAT:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            float* generatedPoints = new float [mGeneratedCoords.size ()];
+            for (int c=0; c<mGeneratedCoords.size (); c++) {
+                generatedPoints [c] = mGeneratedCoords [c];
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            const float* begin = generatedPoints;
+            const float* end = generatedPoints + mGeneratedCoords.size ();
+            t.start ();
+            simplify_opheim <2> (begin, end, minTol.toFloat(), maxTol.toFloat(),
+                                 std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            // done
+            emit SignalCleaningConvertedPolyline ();
+            delete [] generatedPoints;
+            break;
+        }
+        case QVECTOR_DOUBLE:
+        {
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            QVector <qreal>::const_iterator begin = mGeneratedCoords.constBegin ();
+            QVector <qreal>::const_iterator end = mGeneratedCoords.constEnd ();
+            t.start ();
+            simplify_opheim <2> (begin, end, minTol.toDouble(), maxTol.toDouble(),
+                                 std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            break;
+        }
+        case VECTOR_DOUBLE:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::vector <double> generatedPoints = mGeneratedCoords.toStdVector ();
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::vector <double>::const_iterator begin = generatedPoints.begin ();
+            std::vector <double>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_opheim <2> (begin, end, minTol.toDouble(), maxTol.toDouble(),
+                                 std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        case LIST_LONGLONG:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::list <long long> generatedPoints;
+            foreach (double coord, mGeneratedCoords) {
+                generatedPoints.push_back (coord);
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::list <long long>::const_iterator begin = generatedPoints.begin ();
+            std::list <long long>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_opheim <2> (begin, end, minTol.toLongLong(), maxTol.toLongLong(),
+                                 std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        default:
+            break;
+        }
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::SimplifyLa (Container cont, QString tol, int size) {
+        QTime t;
+        int duration = 0;
+
+        mSimplifiedCoords.clear ();
+
+        switch (cont) {
+        case ARRAY_FLOAT:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            float* generatedPoints = new float [mGeneratedCoords.size ()];
+            for (int c=0; c<mGeneratedCoords.size (); c++) {
+                generatedPoints [c] = mGeneratedCoords [c];
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            const float* begin = generatedPoints;
+            const float* end = generatedPoints + mGeneratedCoords.size ();
+            t.start ();
+            simplify_lang <2> (begin, end, tol.toFloat(), size,
+                               std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            // done
+            emit SignalCleaningConvertedPolyline ();
+            delete [] generatedPoints;
+            break;
+        }
+        case QVECTOR_DOUBLE:
+        {
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            QVector <qreal>::const_iterator begin = mGeneratedCoords.constBegin ();
+            QVector <qreal>::const_iterator end = mGeneratedCoords.constEnd ();
+            t.start ();
+            simplify_lang <2> (begin, end, tol.toDouble(), size,
+                               std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            break;
+        }
+        case VECTOR_DOUBLE:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::vector <double> generatedPoints = mGeneratedCoords.toStdVector ();
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::vector <double>::const_iterator begin = generatedPoints.begin ();
+            std::vector <double>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_lang <2> (begin, end, tol.toDouble(), size,
+                               std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        case LIST_LONGLONG:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::list <long long> generatedPoints;
+            foreach (double coord, mGeneratedCoords) {
+                generatedPoints.push_back (coord);
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::list <long long>::const_iterator begin = generatedPoints.begin ();
+            std::list <long long>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_lang <2> (begin, end, tol.toLongLong(), size,
+                               std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        default:
+            break;
+        }
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::SimplifyDP (Container cont, QString tol) {
+        QTime t;
+        int duration = 0;
+
+        mSimplifiedCoords.clear ();
+
+        switch (cont) {
+        case ARRAY_FLOAT:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            float* generatedPoints = new float [mGeneratedCoords.size ()];
+            for (int c=0; c<mGeneratedCoords.size (); c++) {
+                generatedPoints [c] = mGeneratedCoords [c];
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            const float* begin = generatedPoints;
+            const float* end = generatedPoints + mGeneratedCoords.size ();
+            t.start ();
+            simplify_douglas_peucker <2> (begin, end, tol.toFloat(),
+                                          std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            // done
+            emit SignalCleaningConvertedPolyline ();
+            delete [] generatedPoints;
+            break;
+        }
+        case QVECTOR_DOUBLE:
+        {
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            QVector <qreal>::const_iterator begin = mGeneratedCoords.constBegin ();
+            QVector <qreal>::const_iterator end = mGeneratedCoords.constEnd ();
+            t.start ();
+            simplify_douglas_peucker <2> (begin, end, tol.toDouble (),
+                                          std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            break;
+        }
+        case VECTOR_DOUBLE:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::vector <double> generatedPoints = mGeneratedCoords.toStdVector ();
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::vector <double>::const_iterator begin = generatedPoints.begin ();
+            std::vector <double>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_douglas_peucker <2> (begin, end, tol.toDouble (),
+                                          std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        case LIST_LONGLONG:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::list <long long> generatedPoints;
+            foreach (double coord, mGeneratedCoords) {
+                generatedPoints.push_back (coord);
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::list <long long>::const_iterator begin = generatedPoints.begin ();
+            std::list <long long>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_douglas_peucker <2> (begin, end, tol.toLongLong (),
+                                          std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        default:
+            break;
+        }
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::SimplifyDP_variant (Container cont, int count) {
+        QTime t;
+        int duration = 0;
+
+        mSimplifiedCoords.clear ();
+
+        switch (cont) {
+        case ARRAY_FLOAT:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            float* generatedPoints = new float [mGeneratedCoords.size ()];
+            for (int c=0; c<mGeneratedCoords.size (); c++) {
+                generatedPoints [c] = mGeneratedCoords [c];
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            const float* begin = generatedPoints;
+            const float* end = generatedPoints + mGeneratedCoords.size ();
+            t.start ();
+            simplify_douglas_peucker_n <2> (begin, end, count,
+                                            std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            // done
+            emit SignalCleaningConvertedPolyline ();
+            delete [] generatedPoints;
+            break;
+        }
+        case QVECTOR_DOUBLE:
+        {
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            QVector <qreal>::const_iterator begin = mGeneratedCoords.constBegin ();
+            QVector <qreal>::const_iterator end = mGeneratedCoords.constEnd ();
+            t.start ();
+            simplify_douglas_peucker_n <2> (begin, end, count,
+                                            std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            break;
+        }
+        case VECTOR_DOUBLE:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::vector <double> generatedPoints = mGeneratedCoords.toStdVector ();
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::vector <double>::const_iterator begin = generatedPoints.begin ();
+            std::vector <double>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_douglas_peucker_n <2> (begin, end, count,
+                                            std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        case LIST_LONGLONG:
+        {
+            // convert
+            emit SignalConvertingPolyline ();
+            std::list <long long> generatedPoints;
+            foreach (double coord, mGeneratedCoords) {
+                generatedPoints.push_back (coord);
+            }
+            // simplify
+            emit SignalSimplifyingPolyline ();
+            std::list <long long>::const_iterator begin = generatedPoints.begin ();
+            std::list <long long>::const_iterator end = generatedPoints.end ();
+            t.start ();
+            simplify_douglas_peucker_n <2> (begin, end, count,
+                                            std::back_inserter (mSimplifiedCoords));
+            duration = t.elapsed ();
+            emit SignalCleaningConvertedPolyline ();
+            break;
+        }
+        default:
+            break;
+        }
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::SimplifyDP_reference (QString tol) {
+        mSimplifiedCoords.clear();
+        // convert generated polyline to Point array
+        emit SignalConvertingPolyline ();
+        int pointCount = mGeneratedCoords.size () / 2;
+        classic::Point* generatedPoints = new classic::Point [pointCount];
+        classic::Point* simplifiedPoints = new classic::Point [pointCount];
+        for (int i=0; i<pointCount; i++) {
+            generatedPoints [i].x = mGeneratedCoords [i*2];
+            generatedPoints [i].y = mGeneratedCoords [i*2+1];
+        }
+        emit SignalSimplifyingPolyline ();
+        QTime t;
+        t.start ();
+        // simplify
+        int simplCount = classic::poly_simplify (tol.toFloat (), generatedPoints,
+                                                 pointCount, simplifiedPoints);
+        int duration = t.elapsed ();
+        // convert simplified Point array to simplified polyline
+        mSimplifiedCoords.resize (simplCount * 2);
+        for (int i=0; i<simplCount; i++) {
+            mSimplifiedCoords [i*2] = simplifiedPoints [i].x;
+            mSimplifiedCoords [i*2+1] = simplifiedPoints [i].y;
+        }
+        // done
+        delete [] generatedPoints;
+        delete [] simplifiedPoints;
+        
+        DoSignalSimplifiedPolyline (duration);
+    }
+
+    void DPWorker::DoSignalSimplifiedPolyline (qreal duration) {
+        bool validStatistics = false;
+
+        math::Statistics stats = 
+            compute_positional_error_statistics <2> (
+                mGeneratedCoords.constBegin (), mGeneratedCoords.constEnd (),
+                mSimplifiedCoords.constBegin (), mSimplifiedCoords.constEnd (), &validStatistics);
+
+        if (validStatistics) {
+            emit SignalSimplifiedPolyline (duration, mSimplifiedCoords, stats.max, stats.sum, stats.mean, stats.std);
+        }
+        else {
+            emit SignalSimplifiedPolyline (duration, mSimplifiedCoords);
+        }
+    }
+} // namespace psimpl
--- a/lib/psimpl/demo/DPWorker.h
+++ b/lib/psimpl/demo/DPWorker.h
@ -0,0 +1,101 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is
+ * 'psimpl - generic n-dimensional polyline simplification'.
+ *
+ * The Initial Developer of the Original Code is
+ * Elmar de Koning.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+    psimpl - generic n-dimensional polyline simplification
+    Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+
+    This file is part of psimpl, and is hosted at SourceForge:
+    http://sourceforge.net/projects/psimpl/
+*/
+
+#ifndef DPWORKER_H
+#define DPWORKER_H
+
+
+#include <QtCore/QObject>
+#include <QtCore/QVector>
+
+
+namespace psimpl {
+    typedef enum CONTAINER
+    {
+        ARRAY_FLOAT,
+        QVECTOR_DOUBLE,
+        VECTOR_DOUBLE,
+        LIST_LONGLONG,
+    } Container;
+
+    /*!
+        \brief Worker class for generating and simplifying polylines.
+        
+        Polylines are always generated in a QVector <qreal> container. Before simplification the
+        polyline is converted to the specified container type. This allows for easy adding of new 
+        container types.
+        
+    */
+    class DPWorker : public QObject
+    {
+        Q_OBJECT
+
+    public:
+        DPWorker (QObject* inParent = 0);
+
+        void Generate (int inCount);
+        void SimplifyNP (Container cont, int n);
+        void SimplifyRD (Container cont, QString tol);
+        void SimplifyPD (Container cont, QString tol, int repeat);
+        void SimplifyRW (Container cont, QString tol);
+        void SimplifyOp (Container cont, QString minTol, QString maxTol);
+        void SimplifyLa (Container cont, QString tol, int size);
+        void SimplifyDP (Container cont, QString tol);
+        void SimplifyDP_variant (Container cont, int count);
+        void SimplifyDP_reference (QString tol);
+
+        int GetGeneratedPointCount () { return mGeneratedCoords.size () / 2; }
+        int GetSimplifiedGeneratedPointCount () { return mSimplifiedCoords.size () / 2; }
+
+    private:
+        void DoSignalSimplifiedPolyline (qreal duration);
+
+    signals:
+        void SignalGeneratingPolyline ();
+        void SignalConvertingPolyline ();
+        void SignalSimplifyingPolyline ();
+        void SignalCleaningConvertedPolyline ();
+        
+        void SignalGeneratedPolyline (int duration, QVector <qreal>& polyline);
+        void SignalSimplifiedPolyline (int duration, QVector <qreal>& polyline);
+        void SignalSimplifiedPolyline (int duration, QVector <qreal>& polyline, double max, double sum, double mean, double std);
+
+    private:
+        QVector <qreal> mGeneratedCoords;
+        QVector <qreal> mSimplifiedCoords;
+    };
+
+} // namespace psimpl
+
+
+#endif // DPWORKER_H
--- a/lib/psimpl/demo/MainWindow.cpp
+++ b/lib/psimpl/demo/MainWindow.cpp
@ -0,0 +1,256 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is
+ * 'psimpl - generic n-dimensional polyline simplification'.
+ *
+ * The Initial Developer of the Original Code is
+ * Elmar de Koning.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+    psimpl - generic n-dimensional polyline simplification
+    Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+
+    This file is part of psimpl, and is hosted at SourceForge:
+    http://sourceforge.net/projects/psimpl/
+*/
+
+#include "MainWindow.h"
+#include "ui_MainWindow.h"
+#include "DPWorker.h"
+#include <cmath>
+#include <QtGui/QToolButton>
+
+
+namespace psimpl {
+
+    MainWindow::MainWindow (QWidget *parent) :
+        QMainWindow (parent),
+        ui (new Ui::MainWindow)
+    {
+        mWorker = new DPWorker (this);
+
+        ui->setupUi (this);
+        ui->polyTypeComboBox->setCurrentIndex(VECTOR_DOUBLE);
+
+#ifndef _DEBUG
+        ui->algorithmComboBox->removeItem (DOUGLAS_PEUCKER_REFERENCE);
+#endif
+        connect (mWorker, SIGNAL (SignalGeneratingPolyline ()),
+                 this, SLOT (SlotGeneratingPolyline ()));
+        connect (mWorker, SIGNAL (SignalConvertingPolyline ()),
+                 this, SLOT (SlotConvertingPolyline ()));
+        connect (mWorker, SIGNAL (SignalSimplifyingPolyline ()),
+                 this, SLOT (SlotSimplifyingPolyline ()));
+        connect (mWorker, SIGNAL (SignalCleaningConvertedPolyline ()),
+                 this, SLOT (SlotCleaningConvertedPolyline ()));
+
+        connect (mWorker, SIGNAL (SignalGeneratedPolyline (int, QVector <qreal>&)),
+                 this, SLOT (SlotGeneratedPolyline (int, QVector <qreal>&)));
+        connect (mWorker, SIGNAL (SignalSimplifiedPolyline (int, QVector <qreal>&)),
+                 this, SLOT (SlotSimplifiedPolyline (int, QVector <qreal>&)));
+        connect (mWorker, SIGNAL (SignalSimplifiedPolyline (int, QVector <qreal>&, double, double, double, double)),
+                 this, SLOT (SlotSimplifiedPolyline (int, QVector <qreal>&, double, double, double, double)));
+    }
+
+    MainWindow::~MainWindow ()
+    {
+        delete ui;
+        delete mWorker;
+    }
+
+    void MainWindow::changeEvent (QEvent *e)
+    {
+        QMainWindow::changeEvent (e);
+
+        switch (e->type ()) {
+        case QEvent::LanguageChange:
+            ui->retranslateUi (this);
+            break;
+
+        default:
+            break;
+        }
+    }
+
+    void MainWindow::EnableButtons ()
+    {
+        ui->generatePushButton->setEnabled (true);
+        ui->simplifyPushButton->setEnabled (true);
+        ui->togglePushButton->setEnabled(
+            ui->generatedPolylineCheckBox->isChecked () !=
+            ui->simplifiedPolylineCheckBox->isChecked ());
+    }
+
+    void MainWindow::DisableButtons ()
+    {
+        ui->generatePushButton->setDisabled (true);
+        ui->simplifyPushButton->setDisabled (true);
+        ui->togglePushButton->setDisabled (true);
+    }
+
+    void MainWindow::on_generatePushButton_clicked ()
+    {
+        QApplication::setOverrideCursor (QCursor (Qt::WaitCursor));
+        DisableButtons ();
+        mWorker->Generate (ui->polyPointCountSpinBox->value ());
+    }
+
+    void MainWindow::on_simplifyPushButton_clicked ()
+    {
+        QApplication::setOverrideCursor (QCursor (Qt::WaitCursor));
+        DisableButtons ();
+
+        switch (ui->algorithmComboBox->currentIndex ())
+        {
+        case NTH_POINT:
+            mWorker->SimplifyNP ((Container)ui->polyTypeComboBox->currentIndex (), ui->npSpinBox->value ());
+            break;
+
+        case RADIAL_DISTANCE:
+            mWorker->SimplifyRD ((Container)ui->polyTypeComboBox->currentIndex (), ui->rdLineEdit->text ());
+            break;
+
+        case PERPENDICULAR_DISTANCE:
+            mWorker->SimplifyPD ((Container)ui->polyTypeComboBox->currentIndex (), ui->pdLineEdit->text (), ui->pdSpinBox->value ());
+            break;
+
+        case REUMANN_WITKAM:
+            mWorker->SimplifyRW ((Container)ui->polyTypeComboBox->currentIndex (), ui->rwLineEdit->text ());
+            break;
+
+        case OPHEIM:
+            mWorker->SimplifyOp ((Container)ui->polyTypeComboBox->currentIndex (), ui->minOpLineEdit->text (), ui->maxOpLineEdit->text ());
+            break;
+
+        case LANG:
+            mWorker->SimplifyLa ((Container)ui->polyTypeComboBox->currentIndex (), ui->laLineEdit->text (), ui->lookAheadLaSpinBox->value ());
+            break;
+
+        case DOUGLAS_PEUCKER:
+            mWorker->SimplifyDP ((Container)ui->polyTypeComboBox->currentIndex (), ui->dpLineEdit->text ());
+            break;
+
+        case DOUGLAS_PEUCKER_VARIANT:
+            mWorker->SimplifyDP_variant ((Container)ui->polyTypeComboBox->currentIndex (), ui->dpvSpinBox->value ());
+            break;
+
+        case DOUGLAS_PEUCKER_REFERENCE:
+            mWorker->SimplifyDP_reference (ui->dprLineEdit->text ());
+            break;
+        }
+    }
+
+    void MainWindow::on_algorithmComboBox_currentIndexChanged (int index)
+    {
+        if (index == DOUGLAS_PEUCKER_REFERENCE) {
+            ui->polyTypeComboBox->setCurrentIndex (ARRAY_FLOAT);
+            ui->polyTypeComboBox->setDisabled (true);
+        }
+        else {
+            ui->polyTypeComboBox->setEnabled (true);
+        }
+    }
+
+    void MainWindow::on_generatedPolylineCheckBox_toggled (bool checked)
+    {
+        ui->renderArea->SetVisibleGeneratedPolyline (checked);
+        ui->togglePushButton->setDisabled(
+            ui->generatedPolylineCheckBox->isChecked () ==
+            ui->simplifiedPolylineCheckBox->isChecked ());
+        update();
+    }
+
+    void MainWindow::on_simplifiedPolylineCheckBox_toggled (bool checked)
+    {
+        ui->renderArea->SetVisibleSimplifiedPolyline (checked);
+        ui->togglePushButton->setDisabled(
+            ui->generatedPolylineCheckBox->isChecked () ==
+            ui->simplifiedPolylineCheckBox->isChecked ());
+        update();
+    }
+
+    void MainWindow::on_keepAspectRatioCheckBox_toggled (bool checked)
+    {
+        ui->renderArea->SetKeepAspectRatio (checked);
+        update();
+    }
+
+    void MainWindow::SlotGeneratingPolyline () {
+        ui->statusBar->showMessage ("Generating polyline...");
+    }
+
+    void MainWindow::SlotConvertingPolyline () {
+        ui->statusBar->showMessage (QString ("Converting polyline to '%1'...").arg (ui->polyTypeComboBox->currentText ()));
+    }
+
+    void MainWindow::SlotSimplifyingPolyline () {
+        ui->statusBar->showMessage ("Simplifying polyline...");
+    }
+
+    void MainWindow::SlotCleaningConvertedPolyline () {
+        ui->statusBar->showMessage ("Deleting converted polyline...");
+    }
+
+    void MainWindow::SlotGeneratedPolyline (int duration, QVector <qreal>& polyline)
+    {
+        ui->statusBar->showMessage (QString ("Generation took %1 ms").arg (duration));
+        ui->renderArea->SetGeneratedPolyline (polyline);
+        ui->simplGroupBox->setEnabled (true);
+        EnableButtons ();
+        QApplication::restoreOverrideCursor ();
+        update();
+    }
+
+    void MainWindow::SlotSimplifiedPolyline (int duration, QVector <qreal>& polyline)
+    {
+        int pointCount = polyline.count () / 2;
+        ui->maxValueLabel->setText ("-");
+        ui->sumValueLabel->setText ("-");
+        ui->meanValueLabel->setText ("-");
+        ui->stdValueLabel->setText ("-");
+        ui->statusBar->showMessage (
+            QString ("Simplification took %1 ms; %2 (%3%) points remaining").
+                arg (duration).
+                arg (pointCount).
+                arg (100.0 * pointCount / mWorker->GetGeneratedPointCount()));
+        ui->renderArea->SetSimplifiedPolyline(polyline);
+        EnableButtons ();
+        QApplication::restoreOverrideCursor ();
+        update();
+    }
+
+    void MainWindow::SlotSimplifiedPolyline (int duration, QVector <qreal>& polyline, double max, double sum, double mean, double std)
+    {
+        int pointCount = polyline.count () / 2;
+        ui->maxValueLabel->setText (QString::number (max));
+        ui->sumValueLabel->setText (QString::number (sum));
+        ui->meanValueLabel->setText (QString::number (mean));
+        ui->stdValueLabel->setText (QString::number (std));
+        ui->statusBar->showMessage (
+            QString ("Simplification took %1 ms; %2 (%3%) points remaining").
+                arg (duration).
+                arg (pointCount).
+                arg (100.0 * pointCount / mWorker->GetGeneratedPointCount()));
+        ui->renderArea->SetSimplifiedPolyline(polyline);
+        EnableButtons ();
+        QApplication::restoreOverrideCursor ();
+        update();
+    }
+} // namespace psimpl
--- a/lib/psimpl/demo/MainWindow.h
+++ b/lib/psimpl/demo/MainWindow.h
@ -0,0 +1,106 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is
+ * 'psimpl - generic n-dimensional polyline simplification'.
+ *
+ * The Initial Developer of the Original Code is
+ * Elmar de Koning.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+    psimpl - generic n-dimensional polyline simplification
+    Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+
+    This file is part of psimpl, and is hosted at SourceForge:
+    http://sourceforge.net/projects/psimpl/
+*/
+
+#ifndef MAINWINDOW_H
+#define MAINWINDOW_H
+
+
+#include <QtGui/QMainWindow>
+
+
+namespace Ui {
+    class MainWindow;
+}
+
+
+namespace psimpl {
+
+    class DPWorker;
+
+    typedef enum ALGORITHM
+    {
+        NTH_POINT,
+        RADIAL_DISTANCE,
+        PERPENDICULAR_DISTANCE,
+        REUMANN_WITKAM,
+        OPHEIM,
+        LANG,
+        DOUGLAS_PEUCKER,
+        DOUGLAS_PEUCKER_VARIANT,
+        DOUGLAS_PEUCKER_REFERENCE,
+    } Algorithm;
+
+    /*!
+        \brief Mainwindow where polylines can be generated and simplified.
+        
+        Multiple simplification algorithms, implementations and container types can be experimented
+        with.
+    */
+    class MainWindow : public QMainWindow {
+        Q_OBJECT
+
+    public:
+        MainWindow (QWidget *parent = 0);
+        ~MainWindow ();
+
+    protected:
+        void changeEvent (QEvent *e);
+
+    private:
+        void EnableButtons ();
+        void DisableButtons ();
+
+    private:
+        Ui::MainWindow *ui;
+        DPWorker* mWorker;
+
+private slots:
+    void on_simplifiedPolylineCheckBox_toggled(bool checked);
+    void on_generatedPolylineCheckBox_toggled(bool checked);
+    void on_keepAspectRatioCheckBox_toggled(bool checked);
+    void on_simplifyPushButton_clicked ();
+    void on_algorithmComboBox_currentIndexChanged(int index);
+    void on_generatePushButton_clicked ();
+    void SlotGeneratingPolyline ();
+    void SlotConvertingPolyline ();
+    void SlotSimplifyingPolyline ();
+    void SlotCleaningConvertedPolyline ();
+    void SlotGeneratedPolyline (int duration, QVector <qreal>& polyline);
+    void SlotSimplifiedPolyline (int duration, QVector <qreal>& polyline);
+    void SlotSimplifiedPolyline (int duration, QVector <qreal>& polyline, double max, double sum, double mean, double std);
+};
+
+} // namespace psimpl
+
+
+#endif // MAINWINDOW_H
--- a/lib/psimpl/demo/MainWindow.ui
+++ b/lib/psimpl/demo/MainWindow.ui
@ -0,0 +1,855 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>MainWindow</class>
+ <widget class="QMainWindow" name="MainWindow">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>800</width>
+    <height>600</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>psimpl v7 - generic n-dimensional polyline simplification</string>
+  </property>
+  <property name="locale">
+   <locale language="English" country="UnitedStates"/>
+  </property>
+  <widget class="QWidget" name="centralWidget">
+   <layout class="QVBoxLayout" name="verticalLayout_2">
+    <item>
+     <widget class="QLabel" name="label">
+      <property name="text">
+       <string>&lt;!DOCTYPE HTML PUBLIC &quot;-//W3C//DTD HTML 4.0//EN&quot; &quot;http://www.w3.org/TR/REC-html40/strict.dtd&quot;&gt;
+&lt;html&gt;&lt;head&gt;&lt;meta name=&quot;qrichtext&quot; content=&quot;1&quot; /&gt;&lt;style type=&quot;text/css&quot;&gt;
+p, li { white-space: pre-wrap; }
+&lt;/style&gt;&lt;/head&gt;&lt;body style=&quot; font-family:'MS Shell Dlg 2'; font-size:8.25pt; font-weight:400; font-style:normal;&quot;&gt;
+&lt;p align=&quot;center&quot; style=&quot; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;&quot;&gt;&lt;span style=&quot; font-size:10pt; font-weight:600;&quot;&gt;psimple v7&lt;/span&gt;&lt;span style=&quot; font-size:8pt;&quot;&gt; &lt;/span&gt;&lt;span style=&quot; font-size:8pt; color:#000000;&quot;&gt;© Copyright 2010 - 2011 &lt;/span&gt;&lt;a href=&quot;edekoning@gmail.com&quot;&gt;&lt;span style=&quot; font-size:8pt; text-decoration: underline; color:#0000ff;&quot;&gt;Elmar de Koning&lt;/span&gt;&lt;/a&gt;&lt;span style=&quot; font-size:8pt;&quot;&gt;; License - &lt;/span&gt;&lt;a href=&quot;http://www.opensource.org/licenses/mozilla1.1.php&quot;&gt;&lt;span style=&quot; font-size:8pt; text-decoration: underline; color:#0000ff;&quot;&gt;MPL 1.1&lt;/span&gt;&lt;/a&gt;&lt;span style=&quot; font-size:8pt;&quot;&gt;; Website - &lt;/span&gt;&lt;a href=&quot;http://psimpl.sf.net&quot;&gt;&lt;span style=&quot; font-size:8pt; text-decoration: underline; color:#0000ff;&quot;&gt;psimpl.sf.net&lt;/span&gt;&lt;/a&gt;&lt;span style=&quot; font-size:8pt;&quot;&gt;; Article - &lt;/span&gt;&lt;a href=&quot;http://www.codeproject.com/KB/recipes/PolylineSimplification.aspx&quot;&gt;&lt;span style=&quot; font-size:8pt; text-decoration: underline; color:#0000ff;&quot;&gt;CodeProject&lt;/span&gt;&lt;/a&gt;&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+      </property>
+      <property name="openExternalLinks">
+       <bool>true</bool>
+      </property>
+      <property name="textInteractionFlags">
+       <set>Qt::LinksAccessibleByKeyboard|Qt::LinksAccessibleByMouse</set>
+      </property>
+     </widget>
+    </item>
+    <item>
+     <widget class="psimpl::RenderArea" name="renderArea">
+      <property name="sizePolicy">
+       <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+        <horstretch>0</horstretch>
+        <verstretch>3</verstretch>
+       </sizepolicy>
+      </property>
+      <property name="frameShape">
+       <enum>QFrame::StyledPanel</enum>
+      </property>
+      <property name="frameShadow">
+       <enum>QFrame::Sunken</enum>
+      </property>
+     </widget>
+    </item>
+    <item>
+     <layout class="QHBoxLayout" name="horizontalLayout">
+      <item>
+       <widget class="QGroupBox" name="polyGroupBox">
+        <property name="sizePolicy">
+         <sizepolicy hsizetype="Maximum" vsizetype="Preferred">
+          <horstretch>0</horstretch>
+          <verstretch>0</verstretch>
+         </sizepolicy>
+        </property>
+        <property name="title">
+         <string>Polyline</string>
+        </property>
+        <layout class="QGridLayout" name="gridLayout_2">
+         <item row="1" column="0">
+          <widget class="QLabel" name="polyTypeLabel">
+           <property name="text">
+            <string>Type</string>
+           </property>
+           <property name="alignment">
+            <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+           </property>
+          </widget>
+         </item>
+         <item row="1" column="1">
+          <widget class="QComboBox" name="polyTypeComboBox">
+           <item>
+            <property name="text">
+             <string>float []</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>QVector &lt;double&gt;</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>std::vector &lt;double&gt;</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>std::list &lt;long long&gt;</string>
+            </property>
+           </item>
+          </widget>
+         </item>
+         <item row="4" column="1">
+          <widget class="QPushButton" name="generatePushButton">
+           <property name="sizePolicy">
+            <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+             <horstretch>0</horstretch>
+             <verstretch>0</verstretch>
+            </sizepolicy>
+           </property>
+           <property name="text">
+            <string>Generate</string>
+           </property>
+          </widget>
+         </item>
+         <item row="0" column="0">
+          <widget class="QLabel" name="polyPointCountLabel">
+           <property name="text">
+            <string>Point count</string>
+           </property>
+           <property name="alignment">
+            <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+           </property>
+          </widget>
+         </item>
+         <item row="0" column="1">
+          <widget class="QSpinBox" name="polyPointCountSpinBox">
+           <property name="minimum">
+            <number>2</number>
+           </property>
+           <property name="maximum">
+            <number>10000000</number>
+           </property>
+           <property name="singleStep">
+            <number>10000</number>
+           </property>
+           <property name="value">
+            <number>100000</number>
+           </property>
+          </widget>
+         </item>
+         <item row="2" column="1">
+          <spacer name="verticalSpacer_13">
+           <property name="orientation">
+            <enum>Qt::Vertical</enum>
+           </property>
+           <property name="sizeHint" stdset="0">
+            <size>
+             <width>20</width>
+             <height>20</height>
+            </size>
+           </property>
+          </spacer>
+         </item>
+        </layout>
+       </widget>
+      </item>
+      <item>
+       <widget class="QGroupBox" name="simplGroupBox">
+        <property name="enabled">
+         <bool>true</bool>
+        </property>
+        <property name="sizePolicy">
+         <sizepolicy hsizetype="Maximum" vsizetype="Preferred">
+          <horstretch>0</horstretch>
+          <verstretch>0</verstretch>
+         </sizepolicy>
+        </property>
+        <property name="title">
+         <string>Simplification</string>
+        </property>
+        <layout class="QGridLayout" name="gridLayout">
+         <item row="0" column="1">
+          <widget class="QComboBox" name="algorithmComboBox">
+           <item>
+            <property name="text">
+             <string>Nth point</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Radial distance</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Perpendicular distance</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Reumann-Witkam</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Opheim</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Lang</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Douglas-Peucker</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Douglas-Peucker (variant)</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Douglas-Peucker (reference)</string>
+            </property>
+           </item>
+          </widget>
+         </item>
+         <item row="0" column="0">
+          <widget class="QLabel" name="algorithmLabel">
+           <property name="text">
+            <string>Algorithm</string>
+           </property>
+           <property name="alignment">
+            <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+           </property>
+          </widget>
+         </item>
+         <item row="2" column="1">
+          <widget class="QPushButton" name="simplifyPushButton">
+           <property name="enabled">
+            <bool>false</bool>
+           </property>
+           <property name="text">
+            <string>Simplify</string>
+           </property>
+          </widget>
+         </item>
+         <item row="1" column="1">
+          <widget class="QStackedWidget" name="editStackedWidget">
+           <property name="currentIndex">
+            <number>0</number>
+           </property>
+           <widget class="QWidget" name="npPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout_16">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QSpinBox" name="npSpinBox">
+               <property name="maximum">
+                <number>10000000</number>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="rdPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLineEdit" name="rdLineEdit">
+               <property name="text">
+                <string>0</string>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="pdPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout_15">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLineEdit" name="pdLineEdit">
+               <property name="text">
+                <string>0</string>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QSpinBox" name="pdSpinBox">
+               <property name="maximum">
+                <number>1000000</number>
+               </property>
+               <property name="value">
+                <number>1</number>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="rwPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout_6">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLineEdit" name="rwLineEdit">
+               <property name="inputMask">
+                <string/>
+               </property>
+               <property name="text">
+                <string>0</string>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="opPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout_18">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLineEdit" name="minOpLineEdit">
+               <property name="text">
+                <string>0</string>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QLineEdit" name="maxOpLineEdit">
+               <property name="text">
+                <string>0</string>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="laPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout_20">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLineEdit" name="laLineEdit">
+               <property name="text">
+                <string>0</string>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QSpinBox" name="lookAheadLaSpinBox">
+               <property name="maximum">
+                <number>10000000</number>
+               </property>
+               <property name="value">
+                <number>1</number>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="dpPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout_8">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLineEdit" name="dpLineEdit">
+               <property name="text">
+                <string>0</string>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="dpvPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout_7">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QSpinBox" name="dpvSpinBox">
+               <property name="minimum">
+                <number>0</number>
+               </property>
+               <property name="maximum">
+                <number>10000000</number>
+               </property>
+               <property name="singleStep">
+                <number>10</number>
+               </property>
+               <property name="value">
+                <number>0</number>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="dprPage_2">
+            <layout class="QVBoxLayout" name="verticalLayout_12">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLineEdit" name="dprLineEdit">
+               <property name="text">
+                <string>0</string>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+          </widget>
+         </item>
+         <item row="1" column="0">
+          <widget class="QStackedWidget" name="labelStackedWidget">
+           <property name="currentIndex">
+            <number>0</number>
+           </property>
+           <widget class="QWidget" name="npPage">
+            <layout class="QVBoxLayout" name="verticalLayout_14">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="npLabel">
+               <property name="text">
+                <string>n</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="rdPage">
+            <layout class="QVBoxLayout" name="verticalLayout_4">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="rdLabel">
+               <property name="text">
+                <string>Radial distance</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="pdPage">
+            <layout class="QVBoxLayout" name="verticalLayout_13">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="pdLabel">
+               <property name="text">
+                <string>Perpendicular distance</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QLabel" name="repeatLabel">
+               <property name="text">
+                <string>Repeat count</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="rwPage">
+            <layout class="QVBoxLayout" name="verticalLayout_5">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="rwLabel">
+               <property name="text">
+                <string>Perpendicular distance</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="opPage">
+            <layout class="QVBoxLayout" name="verticalLayout_17">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="minOpLabel">
+               <property name="text">
+                <string>Minimum distance</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QLabel" name="maxOpLabel">
+               <property name="text">
+                <string>Maximum distance</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="laPage">
+            <layout class="QVBoxLayout" name="verticalLayout_19">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="laLabel">
+               <property name="text">
+                <string>Perpendicular distance</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QLabel" name="lookAheadLaLabel">
+               <property name="text">
+                <string>Look ahead</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="dpPage">
+            <layout class="QVBoxLayout" name="verticalLayout_9">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="dpLabel">
+               <property name="text">
+                <string>Perpendicular distance</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="dpvPage">
+            <layout class="QVBoxLayout" name="verticalLayout_10">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="dpvLabel">
+               <property name="text">
+                <string>Point count</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+           <widget class="QWidget" name="dprPage">
+            <layout class="QVBoxLayout" name="verticalLayout_11">
+             <property name="margin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="dprLabel">
+               <property name="text">
+                <string>Perpendicular distance</string>
+               </property>
+               <property name="alignment">
+                <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+          </widget>
+         </item>
+        </layout>
+       </widget>
+      </item>
+      <item>
+       <widget class="QGroupBox" name="graphiscGroupBox">
+        <property name="title">
+         <string>Graphics</string>
+        </property>
+        <layout class="QVBoxLayout" name="verticalLayout_3">
+         <item>
+          <widget class="QCheckBox" name="generatedPolylineCheckBox">
+           <property name="text">
+            <string>Generated Polyline</string>
+           </property>
+           <property name="checked">
+            <bool>true</bool>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QCheckBox" name="simplifiedPolylineCheckBox">
+           <property name="text">
+            <string>Simplified Polyline</string>
+           </property>
+           <property name="checked">
+            <bool>false</bool>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QPushButton" name="togglePushButton">
+           <property name="text">
+            <string>Toggle</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QCheckBox" name="keepAspectRatioCheckBox">
+           <property name="text">
+            <string>Keep aspect ratio</string>
+           </property>
+           <property name="checked">
+            <bool>true</bool>
+           </property>
+          </widget>
+         </item>
+        </layout>
+       </widget>
+      </item>
+      <item>
+       <widget class="QGroupBox" name="positionalErrorGroupBox">
+        <property name="toolTip">
+         <string>Positional errors are only calculated for doubles!</string>
+        </property>
+        <property name="title">
+         <string>Positional error</string>
+        </property>
+        <layout class="QGridLayout" name="gridLayout_3">
+         <item row="0" column="0">
+          <widget class="QLabel" name="sumLabel">
+           <property name="text">
+            <string>Sum</string>
+           </property>
+           <property name="alignment">
+            <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+           </property>
+          </widget>
+         </item>
+         <item row="1" column="0">
+          <widget class="QLabel" name="maxLabel">
+           <property name="text">
+            <string>Max</string>
+           </property>
+           <property name="alignment">
+            <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+           </property>
+          </widget>
+         </item>
+         <item row="2" column="0">
+          <widget class="QLabel" name="meanLabel">
+           <property name="text">
+            <string>Mean</string>
+           </property>
+           <property name="alignment">
+            <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+           </property>
+          </widget>
+         </item>
+         <item row="3" column="0">
+          <widget class="QLabel" name="stdLabel">
+           <property name="text">
+            <string>Std</string>
+           </property>
+           <property name="alignment">
+            <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+           </property>
+          </widget>
+         </item>
+         <item row="0" column="1">
+          <widget class="QLabel" name="sumValueLabel">
+           <property name="text">
+            <string>-</string>
+           </property>
+          </widget>
+         </item>
+         <item row="1" column="1">
+          <widget class="QLabel" name="maxValueLabel">
+           <property name="text">
+            <string>-</string>
+           </property>
+          </widget>
+         </item>
+         <item row="2" column="1">
+          <widget class="QLabel" name="meanValueLabel">
+           <property name="text">
+            <string>-</string>
+           </property>
+          </widget>
+         </item>
+         <item row="3" column="1">
+          <widget class="QLabel" name="stdValueLabel">
+           <property name="text">
+            <string>-</string>
+           </property>
+          </widget>
+         </item>
+        </layout>
+       </widget>
+      </item>
+      <item>
+       <spacer name="horizontalSpacer">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>40</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+     </layout>
+    </item>
+   </layout>
+  </widget>
+  <widget class="QStatusBar" name="statusBar"/>
+  <action name="aboutAction">
+   <property name="text">
+    <string>?</string>
+   </property>
+   <property name="toolTip">
+    <string>About psimpl</string>
+   </property>
+   <property name="shortcut">
+    <string>F1</string>
+   </property>
+  </action>
+ </widget>
+ <layoutdefault spacing="6" margin="11"/>
+ <customwidgets>
+  <customwidget>
+   <class>psimpl::RenderArea</class>
+   <extends>QFrame</extends>
+   <header>RenderArea.h</header>
+   <container>1</container>
+  </customwidget>
+ </customwidgets>
+ <tabstops>
+  <tabstop>polyPointCountSpinBox</tabstop>
+  <tabstop>polyTypeComboBox</tabstop>
+  <tabstop>generatePushButton</tabstop>
+  <tabstop>algorithmComboBox</tabstop>
+  <tabstop>npSpinBox</tabstop>
+  <tabstop>rdLineEdit</tabstop>
+  <tabstop>pdLineEdit</tabstop>
+  <tabstop>pdSpinBox</tabstop>
+  <tabstop>rwLineEdit</tabstop>
+  <tabstop>dpLineEdit</tabstop>
+  <tabstop>dpvSpinBox</tabstop>
+  <tabstop>dprLineEdit</tabstop>
+  <tabstop>simplifyPushButton</tabstop>
+  <tabstop>generatedPolylineCheckBox</tabstop>
+  <tabstop>simplifiedPolylineCheckBox</tabstop>
+ </tabstops>
+ <resources/>
+ <connections>
+  <connection>
+   <sender>togglePushButton</sender>
+   <signal>clicked()</signal>
+   <receiver>generatedPolylineCheckBox</receiver>
+   <slot>toggle()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>674</x>
+     <y>559</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>674</x>
+     <y>504</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>togglePushButton</sender>
+   <signal>clicked()</signal>
+   <receiver>simplifiedPolylineCheckBox</receiver>
+   <slot>toggle()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>674</x>
+     <y>559</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>674</x>
+     <y>529</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>algorithmComboBox</sender>
+   <signal>currentIndexChanged(int)</signal>
+   <receiver>labelStackedWidget</receiver>
+   <slot>setCurrentIndex(int)</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>256</x>
+     <y>503</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>210</x>
+     <y>519</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>algorithmComboBox</sender>
+   <signal>currentIndexChanged(int)</signal>
+   <receiver>editStackedWidget</receiver>
+   <slot>setCurrentIndex(int)</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>281</x>
+     <y>490</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>279</x>
+     <y>512</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>
--- a/lib/psimpl/demo/QTRules.rules
+++ b/lib/psimpl/demo/QTRules.rules
@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="utf-8"?>
+<VisualStudioToolFile
+	Name="QT rules"
+	Version="8.00"
+	>
+	<Rules>
+		<CustomBuildRule
+			Name="UIC"
+			DisplayName="UI compiler"
+			CommandLine="$(QTDIR)\bin\uic $(InputPath) -o $(InputDir)\ui_$(InputName).h"
+			Outputs="$(InputDir)\ui_$(InputName).h"
+			FileExtensions="*.ui"
+			ExecutionDescription="Uic&apos;ing $(InputFileName)"
+			>
+			<Properties>
+			</Properties>
+		</CustomBuildRule>
+		<CustomBuildRule
+			Name="MOC"
+			DisplayName="MOC compiler"
+			CommandLine="$(QTDIR)\bin\moc $(InputPath) -o $(InputDir)\moc_$(InputName).cpp"
+			Outputs="$(InputDir)\moc_$(InputName).cpp"
+			FileExtensions="*.moc"
+			ExecutionDescription="Moc&apos;ing $(InputFileName)"
+			>
+			<Properties>
+			</Properties>
+		</CustomBuildRule>
+		<CustomBuildRule
+			Name="RCC"
+			DisplayName="RCC compiler"
+			CommandLine="$(QTDIR)\bin\rcc $(InputPath) -o $(InputDir)\qrc_$(InputName).cpp -name $(ProjectName)"
+			Outputs="$(InputDir)\qrc_$(InputName).cpp"
+			FileExtensions="*.qrc"
+			ExecutionDescription="RCC&apos;ing $(InputFileName)"
+			>
+			<Properties>
+			</Properties>
+		</CustomBuildRule>
+	</Rules>
+</VisualStudioToolFile>
--- a/lib/psimpl/demo/RenderArea.cpp
+++ b/lib/psimpl/demo/RenderArea.cpp
@ -0,0 +1,123 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is
+ * 'psimpl - generic n-dimensional polyline simplification'.
+ *
+ * The Initial Developer of the Original Code is
+ * Elmar de Koning.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+    psimpl - generic n-dimensional polyline simplification
+    Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+
+    This file is part of psimpl, and is hosted at SourceForge:
+    http://sourceforge.net/projects/psimpl/
+*/
+
+#include "RenderArea.h"
+#include <QtGui/QPainter>
+
+
+namespace psimpl {
+
+    RenderArea::RenderArea (QWidget *inParent, Qt::WindowFlags inFlags) :
+        QFrame (inParent, inFlags),
+        mDrawGeneratedPolyline (true),
+        mDrawSimplifiedPolyline (false),
+        mKeepAspectRatio (true)
+    {
+    }
+
+    void RenderArea::paintEvent(QPaintEvent * /*inEvent*/) {
+        if (!mGeneratedPolyline.elementCount ())
+            return;
+
+        QRectF rect = mGeneratedPolyline.boundingRect ();
+        if (!rect.isValid ())
+            return;
+
+        QPainter painter (this);
+
+        if (mKeepAspectRatio) {
+            qreal scale = qMin ((width () - 1) / rect.width (), (height () - 1) / rect.height ());
+            painter.translate ((width () - (rect.width () * scale)) / 2.0,
+                               (height () - (rect.height () * scale)) / 2.0);
+            painter.scale (scale, scale);
+            painter.translate (-rect.left (), -rect.top ());
+        }
+        else {
+            painter.scale ((width () - 1) / rect.width (), (height () - 1) / rect.height ());
+            painter.translate (-rect.left (), -rect.top ());
+        }
+
+        if (mDrawGeneratedPolyline) {
+            painter.setPen (Qt::darkBlue);
+            painter.drawPath (mGeneratedPolyline);
+        }
+
+        if (!mSimplifiedPolyline.elementCount ())
+            return;
+
+        if (mDrawSimplifiedPolyline) {
+            painter.setPen (Qt::darkRed);
+            painter.drawPath (mSimplifiedPolyline);
+        }
+    }
+
+    QPainterPath RenderArea::Convert (QVector <qreal>& polyline)
+    {
+        // limit paths to max 100.000 points to speed up drawing
+        const int threshold = 100000;
+
+        QPainterPath path;
+        if (polyline.empty ()) {
+            return path;
+        }
+        int pointCount = polyline.size () / 2;
+        qreal skipStep = (qreal) (pointCount - threshold) / (qreal) threshold;
+        qreal skipValue = skipStep;
+
+        path.moveTo(polyline [0], polyline [1]);
+        for (int i=1; i<pointCount; i++) {
+            if (skipValue > 1.0) {
+                skipValue -= 1.0;
+            }
+            else {
+                path.lineTo (polyline [i*2], polyline [i*2+1]);
+                skipValue += skipStep;
+            }
+        }
+        int elemCount = path.elementCount ();
+        elemCount++;
+        return path;
+    }
+
+    void RenderArea::SetGeneratedPolyline (QVector <qreal>& polyline)
+    {
+        mSimplifiedPolyline = QPainterPath ();
+        mGeneratedPolyline = Convert (polyline);
+    }
+
+    void RenderArea::SetSimplifiedPolyline (QVector <qreal>& polyline)
+    {
+        mSimplifiedPolyline = Convert (polyline);
+    }
+
+} // namespace psimpl
--- a/lib/psimpl/demo/RenderArea.h
+++ b/lib/psimpl/demo/RenderArea.h
@ -0,0 +1,76 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is
+ * 'psimpl - generic n-dimensional polyline simplification'.
+ *
+ * The Initial Developer of the Original Code is
+ * Elmar de Koning.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+    psimpl - generic n-dimensional polyline simplification
+    Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+
+    This file is part of psimpl, and is hosted at SourceForge:
+    http://sourceforge.net/projects/psimpl/
+*/
+
+#ifndef RENDERAREA_H
+#define RENDERAREA_H
+
+
+#include <QtGui/QFrame>
+#include <QtGui/QPainterPath>
+
+
+namespace psimpl {
+
+    /*!
+        \brief A frame that can draw polylines and their simplification.
+        
+        Note that the point count of each polyline is always limited to 100.000 to speed up drawing.
+    */
+    class RenderArea : public QFrame
+    {
+    public:
+        RenderArea (QWidget *inParent = 0, Qt::WindowFlags inFlags = 0);
+        void SetGeneratedPolyline (QVector <qreal>& polyline);
+        void SetSimplifiedPolyline (QVector <qreal>& polyline);
+        void SetVisibleGeneratedPolyline (bool visible) { mDrawGeneratedPolyline = visible; }
+        void SetVisibleSimplifiedPolyline (bool visible) { mDrawSimplifiedPolyline = visible; }
+        void SetKeepAspectRatio (bool keep) { mKeepAspectRatio = keep; }
+
+    protected:
+        void paintEvent (QPaintEvent *inEvent);
+
+    private:
+        QPainterPath Convert (QVector <qreal>& polyline);
+
+    private:
+        QPainterPath mGeneratedPolyline;
+        QPainterPath mSimplifiedPolyline;
+        bool mDrawGeneratedPolyline;
+        bool mDrawSimplifiedPolyline;
+        bool mKeepAspectRatio;
+    };
+
+} // namespace psimpl
+
+
+#endif // RENDERAREA_H
--- a/lib/psimpl/demo/main.cpp
+++ b/lib/psimpl/demo/main.cpp
@ -0,0 +1,43 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is
+ * 'psimpl - generic n-dimensional polyline simplification'.
+ *
+ * The Initial Developer of the Original Code is
+ * Elmar de Koning.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+    psimpl - generic n-dimensional polyline simplification
+    Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+
+    This file is part of psimpl, and is hosted at SourceForge:
+    http://sourceforge.net/projects/psimpl/
+*/
+
+#include <QtGui/QApplication>
+#include "MainWindow.h"
+
+int main (int argc, char *argv [])
+{
+    QApplication a (argc, argv);
+    psimpl::MainWindow w;
+    w.show ();
+    return a.exec ();
+}
--- a/lib/psimpl/demo/psimpl.pro
+++ b/lib/psimpl/demo/psimpl.pro
@ -0,0 +1,22 @@
+# -------------------------------------------------
+# Project created by QtCreator 2010-06-05T12:09:26
+# -------------------------------------------------
+TARGET = psimpl-demo
+TEMPLATE = app
+VERSION = 7
+SOURCES += main.cpp \
+    MainWindow.cpp \
+    DPWorker.cpp \
+    RenderArea.cpp
+HEADERS += MainWindow.h \
+    DPWorker.h \
+    RenderArea.h \
+    psimpl_reference.h \
+    psimpl.h \
+    ../lib/psimpl.h
+FORMS += MainWindow.ui
+OTHER_FILES += \
+    resource.rc \
+    ../README.txt \
+    ../LICENSE.txt
+RC_FILE = resource.rc
--- a/lib/psimpl/demo/psimpl.vcproj
+++ b/lib/psimpl/demo/psimpl.vcproj
@ -0,0 +1,304 @@
+<?xml version="1.0" encoding="Windows-1252"?>
+<VisualStudioProject
+	ProjectType="Visual C++"
+	Version="9,00"
+	Name="psimpl"
+	ProjectGUID="{B27BE17F-AC18-4797-9E81-1C04D37B8AC4}"
+	RootNamespace="DouglasPeucker"
+	Keyword="Win32Proj"
+	TargetFrameworkVersion="196613"
+	>
+	<Platforms>
+		<Platform
+			Name="Win32"
+		/>
+	</Platforms>
+	<ToolFiles>
+		<ToolFile
+			RelativePath=".\QTRules.rules"
+		/>
+	</ToolFiles>
+	<Configurations>
+		<Configuration
+			Name="Debug|Win32"
+			OutputDirectory="$(SolutionDir)$(ConfigurationName)"
+			IntermediateDirectory="$(ConfigurationName)"
+			ConfigurationType="1"
+			CharacterSet="1"
+			>
+			<Tool
+				Name="VCPreBuildEventTool"
+			/>
+			<Tool
+				Name="MOC"
+			/>
+			<Tool
+				Name="RCC"
+			/>
+			<Tool
+				Name="VCCustomBuildTool"
+			/>
+			<Tool
+				Name="UIC"
+			/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"
+			/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"
+			/>
+			<Tool
+				Name="VCMIDLTool"
+			/>
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="0"
+				AdditionalIncludeDirectories="$(QTDIR)/include"
+				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
+				MinimalRebuild="true"
+				BasicRuntimeChecks="3"
+				RuntimeLibrary="3"
+				UsePrecompiledHeader="0"
+				WarningLevel="4"
+				DebugInformationFormat="4"
+			/>
+			<Tool
+				Name="VCManagedResourceCompilerTool"
+			/>
+			<Tool
+				Name="VCResourceCompilerTool"
+			/>
+			<Tool
+				Name="VCPreLinkEventTool"
+			/>
+			<Tool
+				Name="VCLinkerTool"
+				AdditionalDependencies="qtmaind.lib qtcored4.lib qtguid4.lib"
+				OutputFile="$(OutDir)\$(ProjectName)-demod.exe"
+				LinkIncremental="2"
+				AdditionalLibraryDirectories="$(QTDIR)/lib"
+				GenerateDebugInformation="true"
+				SubSystem="1"
+				TargetMachine="1"
+			/>
+			<Tool
+				Name="VCALinkTool"
+			/>
+			<Tool
+				Name="VCManifestTool"
+			/>
+			<Tool
+				Name="VCXDCMakeTool"
+			/>
+			<Tool
+				Name="VCBscMakeTool"
+			/>
+			<Tool
+				Name="VCFxCopTool"
+			/>
+			<Tool
+				Name="VCAppVerifierTool"
+			/>
+			<Tool
+				Name="VCPostBuildEventTool"
+			/>
+		</Configuration>
+		<Configuration
+			Name="Release|Win32"
+			OutputDirectory="$(SolutionDir)$(ConfigurationName)"
+			IntermediateDirectory="$(ConfigurationName)"
+			ConfigurationType="1"
+			CharacterSet="1"
+			WholeProgramOptimization="1"
+			>
+			<Tool
+				Name="VCPreBuildEventTool"
+			/>
+			<Tool
+				Name="MOC"
+			/>
+			<Tool
+				Name="RCC"
+			/>
+			<Tool
+				Name="VCCustomBuildTool"
+			/>
+			<Tool
+				Name="UIC"
+			/>
+			<Tool
+				Name="VCXMLDataGeneratorTool"
+			/>
+			<Tool
+				Name="VCWebServiceProxyGeneratorTool"
+			/>
+			<Tool
+				Name="VCMIDLTool"
+			/>
+			<Tool
+				Name="VCCLCompilerTool"
+				Optimization="2"
+				EnableIntrinsicFunctions="true"
+				AdditionalIncludeDirectories="$(QTDIR)/include"
+				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
+				RuntimeLibrary="2"
+				EnableFunctionLevelLinking="true"
+				UsePrecompiledHeader="0"
+				WarningLevel="4"
+				DebugInformationFormat="3"
+			/>
+			<Tool
+				Name="VCManagedResourceCompilerTool"
+			/>
+			<Tool
+				Name="VCResourceCompilerTool"
+			/>
+			<Tool
+				Name="VCPreLinkEventTool"
+			/>
+			<Tool
+				Name="VCLinkerTool"
+				AdditionalDependencies="qtmain.lib qtcore4.lib qtgui4.lib"
+				OutputFile="$(OutDir)\$(ProjectName)-demo.exe"
+				LinkIncremental="1"
+				AdditionalLibraryDirectories="$(QTDIR)/lib"
+				GenerateDebugInformation="true"
+				SubSystem="1"
+				OptimizeReferences="2"
+				EnableCOMDATFolding="2"
+				TargetMachine="1"
+			/>
+			<Tool
+				Name="VCALinkTool"
+			/>
+			<Tool
+				Name="VCManifestTool"
+			/>
+			<Tool
+				Name="VCXDCMakeTool"
+			/>
+			<Tool
+				Name="VCBscMakeTool"
+			/>
+			<Tool
+				Name="VCFxCopTool"
+			/>
+			<Tool
+				Name="VCAppVerifierTool"
+			/>
+			<Tool
+				Name="VCPostBuildEventTool"
+			/>
+		</Configuration>
+	</Configurations>
+	<References>
+	</References>
+	<Files>
+		<Filter
+			Name="doc"
+			>
+			<File
+				RelativePath="..\doc\Doxyfile"
+				>
+			</File>
+		</Filter>
+		<Filter
+			Name="demo"
+			>
+			<File
+				RelativePath=".\DPWorker.cpp"
+				>
+			</File>
+			<File
+				RelativePath=".\DPWorker.h"
+				>
+				<FileConfiguration
+					Name="Debug|Win32"
+					>
+					<Tool
+						Name="MOC"
+					/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="Release|Win32"
+					>
+					<Tool
+						Name="MOC"
+					/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath=".\main.cpp"
+				>
+			</File>
+			<File
+				RelativePath=".\MainWindow.cpp"
+				>
+			</File>
+			<File
+				RelativePath=".\MainWindow.h"
+				>
+				<FileConfiguration
+					Name="Debug|Win32"
+					>
+					<Tool
+						Name="MOC"
+					/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="Release|Win32"
+					>
+					<Tool
+						Name="MOC"
+					/>
+				</FileConfiguration>
+			</File>
+			<File
+				RelativePath=".\MainWindow.ui"
+				>
+			</File>
+			<File
+				RelativePath=".\moc_DPWorker.cpp"
+				>
+			</File>
+			<File
+				RelativePath=".\moc_MainWindow.cpp"
+				>
+			</File>
+			<File
+				RelativePath=".\psimpl_reference.h"
+				>
+			</File>
+			<File
+				RelativePath=".\RenderArea.cpp"
+				>
+			</File>
+			<File
+				RelativePath=".\RenderArea.h"
+				>
+			</File>
+			<File
+				RelativePath=".\ui_MainWindow.h"
+				>
+			</File>
+		</Filter>
+		<Filter
+			Name="lib"
+			>
+			<File
+				RelativePath="..\lib\psimpl.h"
+				>
+			</File>
+		</Filter>
+		<File
+			RelativePath="..\LICENSE.txt"
+			>
+		</File>
+		<File
+			RelativePath="..\README.txt"
+			>
+		</File>
+	</Files>
+	<Globals>
+	</Globals>
+</VisualStudioProject>
--- a/lib/psimpl/demo/psimpl_reference.h
+++ b/lib/psimpl/demo/psimpl_reference.h
@ -0,0 +1,238 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is
+ * 'psimpl - generic n-dimensional polyline simplification'.
+ *
+ * The Initial Developer of the Original Code is
+ * Elmar de Koning.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+    psimpl - generic n-dimensional polyline simplification
+    Copyright (C) 2010-2011 Elmar de Koning, edekoning@gmail.com
+
+    This file is part of psimpl, and is hosted at SourceForge:
+    http://sourceforge.net/projects/psimpl/
+*/
+
+#ifndef PSIMPL_CLASSIC_H
+#define PSIMPL_CLASSIC_H
+
+#include <stack>
+
+namespace psimpl {
+    namespace classic {
+        // Contains a minimal modified version of the Douglas-Peucker recursive simplification
+        // routine as available from www.softsurfer.com. Modifications include:
+        // - Removed recursion by using a stack
+        // - Added minimal Point, Vector, and Segment classes as needed by the algorithm
+
+
+        // minimal point class
+        class Point {
+        public:
+            Point () :
+                x (0.f),
+                y (0.f)
+            {}
+
+            Point (float x, float y) :
+                x (x),
+                y (y)
+            {}
+
+            float x, y;
+        };
+
+        // reuse the point class for a vector
+        typedef Point Vector;
+
+        // operators as needed by the algorithm
+        Point operator+ (const Point& P, const Vector& V) {
+            return Point (P.x+V.x, P.y+V.y);
+        }
+
+        Vector operator- (const Point& P0, const Point& P1) {
+            return Vector (P0.x-P1.x, P0.y-P1.y);
+        }
+
+        Vector operator* (double s, const Vector& V) {
+            return Vector (s*V.x, s*V.y);
+        }
+
+        // minimal segment class
+        class Segment {
+        public:
+            Segment (const Point& P0, const Point& P1) :
+                P0(P0),
+                P1(P1)
+            {}
+
+            Point P0;
+            Point P1;
+        };
+
+        // define the stack and sub poly that are used to replace the original recusion
+        typedef std::pair< int, int > SubPoly;
+        typedef std::stack< SubPoly > Stack;
+
+
+        // Copyright 2002, softSurfer (www.softsurfer.com)
+        // This code may be freely used and modified for any purpose
+        // providing that this copyright notice is included with it.
+        // SoftSurfer makes no warranty for this code, and cannot be held
+        // liable for any real or imagined damage resulting from its use.
+        // Users of this code must verify correctness for their application.
+
+        // Assume that classes are already given for the objects:
+        //    Point and Vector with
+        //        coordinates {float x, y, z;}    // as many as are needed
+        //        operators for:
+        //            == to test equality
+        //            != to test inequality
+        //            (Vector)0 = (0,0,0)         (null vector)
+        //            Point  = Point ± Vector
+        //            Vector = Point - Point
+        //            Vector = Vector ± Vector
+        //            Vector = Scalar * Vector    (scalar product)
+        //            Vector = Vector * Vector    (cross product)
+        //    Segment with defining endpoints {Point P0, P1;}
+        //===================================================================
+
+        // dot product (3D) which allows vector operations in arguments
+        #define __dot(u,v)   ((u).x * (v).x + (u).y * (v).y)
+        #define __norm2(v)   __dot(v,v)        // norm2 = squared length of vector
+        #define __norm(v)    sqrt(__norm2(v))  // norm = length of vector
+        #define __d2(u,v)    __norm2(u-v)      // distance squared = norm2 of difference
+        #define __d(u,v)     __norm(u-v)       // distance = norm of difference
+
+        // simplifyDP():
+        //  This is the Douglas-Peucker recursive simplification routine
+        //  It just marks vertices that are part of the simplified polyline
+        //  for approximating the polyline subchain v[j] to v[k].
+        //    Input:  tol = approximation tolerance
+        //            v[] = polyline array of vertex points
+        //            j,k = indices for the subchain v[j] to v[k]
+        //    Output: mk[] = array of markers matching vertex array v[]
+        void
+        simplifyDP( Stack& stack, float tol, Point* v, int j, int k, int* mk )
+        {
+            if (k <= j+1) // there is nothing to simplify
+                return;
+
+            // check for adequate approximation by segment S from v[j] to v[k]
+            int     maxi = j;          // index of vertex farthest from S
+            float   maxd2 = 0;         // distance squared of farthest vertex
+            float   tol2 = tol * tol;  // tolerance squared
+            Segment S (v[j], v[k]);  // segment from v[j] to v[k]
+            Vector  u = S.P1 - S.P0;   // segment direction vector
+            double  cu = __dot(u,u);     // segment length squared
+
+            // test each vertex v[i] for max distance from S
+            // compute using the Feb 2001 Algorithm's dist_Point_to_Segment()
+            // Note: this works in any dimension (2D, 3D, ...)
+            Vector  w;
+            Point   Pb;                // base of perpendicular from v[i] to S
+            double  b, cw, dv2;        // dv2 = distance v[i] to S squared
+
+            for (int i=j+1; i<k; i++)
+            {
+                // compute distance squared
+                w = v[i] - S.P0;
+                cw = __dot(w,u);
+                if ( cw <= 0 )
+                    dv2 = __d2(v[i], S.P0);
+                else if ( cu <= cw )
+                    dv2 = __d2(v[i], S.P1);
+                else {
+                    b = cw / cu;
+                    Pb = S.P0 + b * u;
+                    dv2 = __d2(v[i], Pb);
+                }
+                // test with current max distance squared
+                if (dv2 <= maxd2)
+                    continue;
+                // v[i] is a new max vertex
+                maxi = i;
+                maxd2 = dv2;
+            }
+            if (maxd2 > tol2)        // error is worse than the tolerance
+            {
+                // split the polyline at the farthest vertex from S
+                mk[maxi] = 1;      // mark v[maxi] for the simplified polyline
+                // recursively simplify the two subpolylines at v[maxi]
+                stack.push( std::make_pair (j, maxi));
+                stack.push( std::make_pair (maxi, k));
+            }
+            // else the approximation is OK, so ignore intermediate vertices
+            return;
+        }
+
+        // poly_simplify():
+        //    Input:  tol = approximation tolerance
+        //            V[] = polyline array of vertex points
+        //            n   = the number of points in V[]
+        //    Output: sV[]= simplified polyline vertices (max is n)
+        //    Return: m   = the number of points in sV[]
+        int
+        poly_simplify(float tol, Point* V, int n, Point* sV )
+        {
+            int    i, k, m, pv;            // misc counters
+            float  tol2 = tol * tol;       // tolerance squared
+            Point* vt = new Point[n];      // vertex buffer
+            int*   mk = new int[n];        // marker buffer
+            for (i=0; i<n; i++) {
+                mk[i] = 0;
+            }
+
+            // STAGE 1.  Vertex Reduction within tolerance of prior vertex cluster
+            vt[0] = V[0];              // start at the beginning
+            for (i=k=1, pv=0; i<n; i++) {
+                if (__d2(V[i], V[pv]) < tol2)
+                    continue;
+                vt[k++] = V[i];
+                pv = i;
+            }
+            if (pv < n-1)
+                vt[k++] = V[n-1];      // finish at the end
+
+            // STAGE 2.  Douglas-Peucker polyline simplification
+            mk[0] = mk[k-1] = 1;                    // mark the first and last vertices
+            Stack stack;                            // use a stack i.s.o. recursion (NEW)
+            stack.push( std::make_pair( 0, k-1 ));  // add complete poly
+            while (!stack.empty()) {
+                SubPoly subPoly = stack.top();      // take a sub poly
+                stack.pop();                        // and simplify it
+                simplifyDP( stack, tol, vt, subPoly.first, subPoly.second, mk );
+            }
+
+            // copy marked vertices to the output simplified polyline
+            for (i=m=0; i<k; i++) {
+                if (mk[i])
+                    sV[m++] = vt[i];
+            }
+            delete vt;
+            delete mk;
+            return m;         // m vertices in simplified polyline
+        }
+        //===================================================================
+    }
+}
+
+#endif // PSIMPL_CLASSIC_H
--- a/lib/psimpl/demo/resource.rc
+++ b/lib/psimpl/demo/resource.rc
@ -0,0 +1,34 @@
+# if defined(UNDER_CE)
+#  include <winbase.h>
+# else
+#  include <winver.h>
+# endif
+
+VS_VERSION_INFO VERSIONINFO
+        FILEVERSION 7,0,0,0
+        PRODUCTVERSION 7,0,0,0
+	FILEFLAGSMASK 0x3fL
+#ifdef _DEBUG
+	FILEFLAGS VS_FF_DEBUG
+#else
+	FILEFLAGS 0x0L
+#endif
+	FILEOS VOS__WINDOWS32
+	FILETYPE VFT_DLL
+	FILESUBTYPE 0x0L
+	BEGIN
+		BLOCK "StringFileInfo"
+		BEGIN
+			BLOCK "040904B0"
+			BEGIN
+				VALUE "CompanyName", "Elmar de Koning\0"
+				VALUE "FileDescription", "psimpl demo application\0"
+                                VALUE "FileVersion", "7.0.0.0\0"
+				VALUE "LegalCopyright", "Copyright (C) 2010-2011 Elmar de Koning\0"
+				VALUE "OriginalFilename", "psimpl-demo.exe\0"
+				VALUE "ProductName", "psimpl - generic n-dimensional polyline simplification\0"
+			END
+		END
+	END
+/* End of Version info */
+
--- a/lib/psimpl/psimpl.h
+++ b/lib/psimpl/psimpl.h
--- a/lib/simplify-js-alternative/Makefile
+++ b/lib/simplify-js-alternative/Makefile
@ -0,0 +1,2 @@
+simplify.diff:
+	diff ../turf-simplify/lib/simplify.js simplify.js > simplify.diff || true
--- a/lib/simplify-js-alternative/README.md
+++ b/lib/simplify-js-alternative/README.md
@ -0,0 +1 @@
+This is an alternative Simplify.js version to take coordinates as a nested array.
--- a/lib/simplify-js-alternative/simplify.diff
+++ b/lib/simplify-js-alternative/simplify.diff
@ -0,0 +1,42 @@
+1,9d0
+< /*
+<  (c) 2013, Vladimir Agafonkin
+<  Simplify.js, a high-performance JS polyline simplification library
+<  mourner.github.io/simplify-js
+< */
+< 
+< // to suit your point format, run search/replace for '.x' and '.y';
+< // for 3D version, see 3d branch (configurability would draw significant performance overhead)
+< 
+13,14c4,5
+<     var dx = p1.x - p2.x,
+<         dy = p1.y - p2.y;
+---
+>     var dx = p1[0] - p2[0],
+>         dy = p1[1] - p2[1];
+22,25c13,16
+<     var x = p1.x,
+<         y = p1.y,
+<         dx = p2.x - x,
+<         dy = p2.y - y;
+---
+>     var x = p1[0],
+>         y = p1[1],
+>         dx = p2[0] - x,
+>         dy = p2[1] - y;
+29c20
+<         var t = ((p.x - x) * dx + (p.y - y) * dy) / (dx * dx + dy * dy);
+---
+>         var t = ((p[0] - x) * dx + (p[1] - y) * dy) / (dx * dx + dy * dy);
+32,33c23,24
+<             x = p2.x;
+<             y = p2.y;
+---
+>             x = p2[0];
+>             y = p2[1];
+41,42c32,33
+<     dx = p.x - x;
+<     dy = p.y - y;
+---
+>     dx = p[0] - x;
+>     dy = p[1] - y;
--- a/lib/simplify-js-alternative/simplify.js
+++ b/lib/simplify-js-alternative/simplify.js
@ -0,0 +1,102 @@
+// square distance between 2 points
+function getSqDist(p1, p2) {
+
+    var dx = p1[0] - p2[0],
+        dy = p1[1] - p2[1];
+
+    return dx * dx + dy * dy;
+}
+
+// square distance from a point to a segment
+function getSqSegDist(p, p1, p2) {
+
+    var x = p1[0],
+        y = p1[1],
+        dx = p2[0] - x,
+        dy = p2[1] - y;
+
+    if (dx !== 0 || dy !== 0) {
+
+        var t = ((p[0] - x) * dx + (p[1] - y) * dy) / (dx * dx + dy * dy);
+
+        if (t > 1) {
+            x = p2[0];
+            y = p2[1];
+
+        } else if (t > 0) {
+            x += dx * t;
+            y += dy * t;
+        }
+    }
+
+    dx = p[0] - x;
+    dy = p[1] - y;
+
+    return dx * dx + dy * dy;
+}
+// rest of the code doesn't care about point format
+
+// basic distance-based simplification
+function simplifyRadialDist(points, sqTolerance) {
+
+    var prevPoint = points[0],
+        newPoints = [prevPoint],
+        point;
+
+    for (var i = 1, len = points.length; i < len; i++) {
+        point = points[i];
+
+        if (getSqDist(point, prevPoint) > sqTolerance) {
+            newPoints.push(point);
+            prevPoint = point;
+        }
+    }
+
+    if (prevPoint !== point) newPoints.push(point);
+
+    return newPoints;
+}
+
+function simplifyDPStep(points, first, last, sqTolerance, simplified) {
+    var maxSqDist = sqTolerance,
+        index;
+
+    for (var i = first + 1; i < last; i++) {
+        var sqDist = getSqSegDist(points[i], points[first], points[last]);
+
+        if (sqDist > maxSqDist) {
+            index = i;
+            maxSqDist = sqDist;
+        }
+    }
+
+    if (maxSqDist > sqTolerance) {
+        if (index - first > 1) simplifyDPStep(points, first, index, sqTolerance, simplified);
+        simplified.push(points[index]);
+        if (last - index > 1) simplifyDPStep(points, index, last, sqTolerance, simplified);
+    }
+}
+
+// simplification using Ramer-Douglas-Peucker algorithm
+function simplifyDouglasPeucker(points, sqTolerance) {
+    var last = points.length - 1;
+
+    var simplified = [points[0]];
+    simplifyDPStep(points, 0, last, sqTolerance, simplified);
+    simplified.push(points[last]);
+
+    return simplified;
+}
+
+// both algorithms combined for awesome performance
+export default function simplify(points, tolerance, highestQuality) {
+
+    if (points.length <= 2) return points;
+
+    var sqTolerance = tolerance !== undefined ? tolerance * tolerance : 1;
+
+    points = highestQuality ? points : simplifyRadialDist(points, sqTolerance);
+    points = simplifyDouglasPeucker(points, sqTolerance);
+
+    return points;
+}
--- a/lib/simplify-js/.gitignore
+++ b/lib/simplify-js/.gitignore
@ -0,0 +1,28 @@
+### Node template
+# Logs
+logs
+*.log
+
+# Runtime data
+pids
+*.pid
+*.seed
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+
+# Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (http://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directory
+# https://docs.npmjs.com/misc/faq#should-i-check-my-node-modules-folder-into-git
+node_modules
--- a/lib/simplify-js/LICENSE
+++ b/lib/simplify-js/LICENSE
@ -0,0 +1,22 @@
+Copyright (c) 2017, Vladimir Agafonkin
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification, are
+permitted provided that the following conditions are met:
+
+   1. Redistributions of source code must retain the above copyright notice, this list of
+      conditions and the following disclaimer.
+
+   2. Redistributions in binary form must reproduce the above copyright notice, this list
+      of conditions and the following disclaimer in the documentation and/or other materials
+      provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
--- a/lib/simplify-js/README.md
+++ b/lib/simplify-js/README.md
@ -0,0 +1,19 @@
+Simplify.js is a high-performance JavaScript polyline simplification library by Vladimir Agafonkin, extracted from [Leaflet](http://leafletjs.com).
+
+Checkout the demo with docs: http://mourner.github.io/simplify-js/
+
+#### Ports
+
+ * Python: [omarestrella / simplify.py](https://github.com/omarestrella/simplify.py) (by Omar Estrella)
+ * PHP: [AKeN / simplify-php](https://github.com/AKeN/simplify-php) (by Rotari Gheorghe)
+ * PHP: [andreychumak / simplify-php](https://github.com/andreychumak/simplify-php) (by Andrey Chumak)
+ * Java: [ekeneijeoma / simplify-java](https://github.com/ekeneijeoma/simplify-java) (by Ekene Ijeoma)
+ * Java: [hgoebl / simplify-java](https://github.com/hgoebl/simplify-java) (by Heinrich Göbl)
+ * Processing: [ekeneijeoma / simplify-processing](https://github.com/ekeneijeoma/simplify-processing) (by Ekene Ijeoma)
+ * AS3: [fnicollet / simplify-as3](https://github.com/fnicollet/simplify-as3) (by Fabien Nicollet)
+ * Rust: [calvinmetcalf / simplify-rs](https://github.com/calvinmetcalf/simplify-rs) (by Calvin Metcalf)
+ * Ruby: [odlp / simplify_rb](https://github.com/odlp/simplify_rb) (by Oliver Peate)
+ * Go: [yrsh / simplify_go](https://github.com/yrsh/simplify-go) (by Anton Korotkikh)
+ * C# (Portable): [imshz / simplify-net](https://github.com/imshz/simplify-net) (by Shees Ul-Hassan)
+ * Swift: [malcommac / SwiftSimplify](https://github.com/malcommac/SwiftSimplify) (by Daniele Margutti)
+ * Unreal Engine: [SINTEF-9012 / SimplifyUnreal](https://github.com/SINTEF-9012/SimplifyUnreal) (by Antoine Pultier)
--- a/lib/simplify-js/bench/bench.js
+++ b/lib/simplify-js/bench/bench.js
@ -0,0 +1,19 @@
+
+var Benchmark = require('benchmark');
+var simplify = require('../simplify');
+
+var points = require('../test/fixtures/1k.json');
+
+console.log('Benchmarking simplify on ' + points.length + ' points...');
+
+new Benchmark.Suite()
+.add('simplify (HQ)', function() {
+    simplify(points, 1, true);
+})
+.add('simplify', function() {
+    simplify(points, 1, false);
+})
+.on('cycle', function(event) {
+    console.log(String(event.target));
+})
+.run();
--- a/lib/simplify-js/index.d.ts
+++ b/lib/simplify-js/index.d.ts
@ -0,0 +1,9 @@
+interface Point {
+	x: number;
+	y: number;
+}
+
+declare function simplify (points: Point[], tolerance?: number, highQuality?: boolean): Point[];
+declare namespace simplify {}
+
+export = simplify;
--- a/lib/simplify-js/package.json
+++ b/lib/simplify-js/package.json
@ -0,0 +1,38 @@
+{
+  "name": "simplify-js",
+  "version": "1.2.3",
+  "description": "A high-performance JavaScript 2D/3D polyline simplification library",
+  "homepage": "http://mourner.github.com/simplify-js/",
+  "author": "Vladimir Agafonkin",
+  "license": "BSD-2-Clause",
+  "keywords": [
+    "math",
+    "geometry",
+    "polyline",
+    "simplification"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/mourner/simplify-js.git"
+  },
+  "main": "simplify.js",
+  "files": [
+    "index.d.ts",
+    "simplify.js"
+  ],
+  "types": "index.d.ts",
+  "devDependencies": {
+    "benchmark": "^2.1.4",
+    "faucet": "0.0.1",
+    "jshint": "^2.9.5",
+    "tape": "^4.8.0"
+  },
+  "scripts": {
+    "test": "jshint simplify.js test/test.js && node test/test.js | faucet"
+  },
+  "jshintConfig": {
+    "quotmark": "single",
+    "trailing": true,
+    "unused": true
+  }
+}
--- a/lib/simplify-js/simplify.js
+++ b/lib/simplify-js/simplify.js
@ -0,0 +1,123 @@
+/*
+ (c) 2017, Vladimir Agafonkin
+ Simplify.js, a high-performance JS polyline simplification library
+ mourner.github.io/simplify-js
+*/
+
+(function () { 'use strict';
+
+// to suit your point format, run search/replace for '.x' and '.y';
+// for 3D version, see 3d branch (configurability would draw significant performance overhead)
+
+// square distance between 2 points
+function getSqDist(p1, p2) {
+
+    var dx = p1.x - p2.x,
+        dy = p1.y - p2.y;
+
+    return dx * dx + dy * dy;
+}
+
+// square distance from a point to a segment
+function getSqSegDist(p, p1, p2) {
+
+    var x = p1.x,
+        y = p1.y,
+        dx = p2.x - x,
+        dy = p2.y - y;
+
+    if (dx !== 0 || dy !== 0) {
+
+        var t = ((p.x - x) * dx + (p.y - y) * dy) / (dx * dx + dy * dy);
+
+        if (t > 1) {
+            x = p2.x;
+            y = p2.y;
+
+        } else if (t > 0) {
+            x += dx * t;
+            y += dy * t;
+        }
+    }
+
+    dx = p.x - x;
+    dy = p.y - y;
+
+    return dx * dx + dy * dy;
+}
+// rest of the code doesn't care about point format
+
+// basic distance-based simplification
+function simplifyRadialDist(points, sqTolerance) {
+
+    var prevPoint = points[0],
+        newPoints = [prevPoint],
+        point;
+
+    for (var i = 1, len = points.length; i < len; i++) {
+        point = points[i];
+
+        if (getSqDist(point, prevPoint) > sqTolerance) {
+            newPoints.push(point);
+            prevPoint = point;
+        }
+    }
+
+    if (prevPoint !== point) newPoints.push(point);
+
+    return newPoints;
+}
+
+function simplifyDPStep(points, first, last, sqTolerance, simplified) {
+    var maxSqDist = sqTolerance,
+        index;
+
+    for (var i = first + 1; i < last; i++) {
+        var sqDist = getSqSegDist(points[i], points[first], points[last]);
+
+        if (sqDist > maxSqDist) {
+            index = i;
+            maxSqDist = sqDist;
+        }
+    }
+
+    if (maxSqDist > sqTolerance) {
+        if (index - first > 1) simplifyDPStep(points, first, index, sqTolerance, simplified);
+        simplified.push(points[index]);
+        if (last - index > 1) simplifyDPStep(points, index, last, sqTolerance, simplified);
+    }
+}
+
+// simplification using Ramer-Douglas-Peucker algorithm
+function simplifyDouglasPeucker(points, sqTolerance) {
+    var last = points.length - 1;
+
+    var simplified = [points[0]];
+    simplifyDPStep(points, 0, last, sqTolerance, simplified);
+    simplified.push(points[last]);
+
+    return simplified;
+}
+
+// both algorithms combined for awesome performance
+function simplify(points, tolerance, highestQuality) {
+
+    if (points.length <= 2) return points;
+
+    var sqTolerance = tolerance !== undefined ? tolerance * tolerance : 1;
+
+    points = highestQuality ? points : simplifyRadialDist(points, sqTolerance);
+    points = simplifyDouglasPeucker(points, sqTolerance);
+
+    return points;
+}
+
+// export as AMD module / Node module / browser or worker variable
+if (typeof define === 'function' && define.amd) define(function() { return simplify; });
+else if (typeof module !== 'undefined') {
+    module.exports = simplify;
+    module.exports.default = simplify;
+} else if (typeof self !== 'undefined') self.simplify = simplify;
+else window.simplify = simplify;
+
+})();
--- a/lib/simplify-js/test/fixtures/1k.json
+++ b/lib/simplify-js/test/fixtures/1k.json
--- a/lib/simplify-js/test/test.js
+++ b/lib/simplify-js/test/test.js
@ -0,0 +1,60 @@
+var points = [
+    {x:224.55,y:250.15},{x:226.91,y:244.19},{x:233.31,y:241.45},{x:234.98,y:236.06},
+    {x:244.21,y:232.76},{x:262.59,y:215.31},{x:267.76,y:213.81},{x:273.57,y:201.84},
+    {x:273.12,y:192.16},{x:277.62,y:189.03},{x:280.36,y:181.41},{x:286.51,y:177.74},
+    {x:292.41,y:159.37},{x:296.91,y:155.64},{x:314.95,y:151.37},{x:319.75,y:145.16},
+    {x:330.33,y:137.57},{x:341.48,y:139.96},{x:369.98,y:137.89},{x:387.39,y:142.51},
+    {x:391.28,y:139.39},{x:409.52,y:141.14},{x:414.82,y:139.75},{x:427.72,y:127.30},
+    {x:439.60,y:119.74},{x:474.93,y:107.87},{x:486.51,y:106.75},{x:489.20,y:109.45},
+    {x:493.79,y:108.63},{x:504.74,y:119.66},{x:512.96,y:122.35},{x:518.63,y:120.89},
+    {x:524.09,y:126.88},{x:529.57,y:127.86},{x:534.21,y:140.93},{x:539.27,y:147.24},
+    {x:567.69,y:148.91},{x:575.25,y:157.26},{x:580.62,y:158.15},{x:601.53,y:156.85},
+    {x:617.74,y:159.86},{x:622.00,y:167.04},{x:629.55,y:194.60},{x:638.90,y:195.61},
+    {x:641.26,y:200.81},{x:651.77,y:204.56},{x:671.55,y:222.55},{x:683.68,y:217.45},
+    {x:695.25,y:219.15},{x:700.64,y:217.98},{x:703.12,y:214.36},{x:712.26,y:215.87},
+    {x:721.49,y:212.81},{x:727.81,y:213.36},{x:729.98,y:208.73},{x:735.32,y:208.20},
+    {x:739.94,y:204.77},{x:769.98,y:208.42},{x:779.60,y:216.87},{x:784.20,y:218.16},
+    {x:800.24,y:214.62},{x:810.53,y:219.73},{x:817.19,y:226.82},{x:820.77,y:236.17},
+    {x:827.23,y:236.16},{x:829.89,y:239.89},{x:851.00,y:248.94},{x:859.88,y:255.49},
+    {x:865.21,y:268.53},{x:857.95,y:280.30},{x:865.48,y:291.45},{x:866.81,y:298.66},
+    {x:864.68,y:302.71},{x:867.79,y:306.17},{x:859.87,y:311.37},{x:860.08,y:314.35},
+    {x:858.29,y:314.94},{x:858.10,y:327.60},{x:854.54,y:335.40},{x:860.92,y:343.00},
+    {x:856.43,y:350.15},{x:851.42,y:352.96},{x:849.84,y:359.59},{x:854.56,y:365.53},
+    {x:849.74,y:370.38},{x:844.09,y:371.89},{x:844.75,y:380.44},{x:841.52,y:383.67},
+    {x:839.57,y:390.40},{x:845.59,y:399.05},{x:848.40,y:407.55},{x:843.71,y:411.30},
+    {x:844.09,y:419.88},{x:839.51,y:432.76},{x:841.33,y:441.04},{x:847.62,y:449.22},
+    {x:847.16,y:458.44},{x:851.38,y:462.79},{x:853.97,y:471.15},{x:866.36,y:480.77}
+];
+
+var simplified = [
+    {x:224.55,y:250.15},{x:267.76,y:213.81},{x:296.91,y:155.64},{x:330.33,y:137.57},
+    {x:409.52,y:141.14},{x:439.60,y:119.74},{x:486.51,y:106.75},{x:529.57,y:127.86},
+    {x:539.27,y:147.24},{x:617.74,y:159.86},{x:629.55,y:194.60},{x:671.55,y:222.55},
+    {x:727.81,y:213.36},{x:739.94,y:204.77},{x:769.98,y:208.42},{x:779.60,y:216.87},
+    {x:800.24,y:214.62},{x:820.77,y:236.17},{x:859.88,y:255.49},{x:865.21,y:268.53},
+    {x:857.95,y:280.30},{x:867.79,y:306.17},{x:859.87,y:311.37},{x:854.54,y:335.40},
+    {x:860.92,y:343.00},{x:849.84,y:359.59},{x:854.56,y:365.53},{x:844.09,y:371.89},
+    {x:839.57,y:390.40},{x:848.40,y:407.55},{x:839.51,y:432.76},{x:853.97,y:471.15},
+    {x:866.36,y:480.77}
+];
+
+var simplify = require('../simplify'),
+    t = require('tape');
+
+t('simplifies points correctly with the given tolerance', function (t) {
+    var result = simplify(points, 5);
+    t.same(result, simplified);
+    t.end();
+});
+
+t('just return the points if it has only one point', function(t){
+    var result = simplify([{x:1, y:2}]);
+    t.same(result, [{x:1, y:2}]);
+    t.end();
+});
+
+t('just return the points if it has no points', function(t){
+    var result = simplify([]);
+    t.same(result, []);
+    t.end();
+});
--- a/lib/simplify-wasm/Makefile
+++ b/lib/simplify-wasm/Makefile
@ -0,0 +1,13 @@
+OPTIMIZE="-O3"
+
+simplify.wasm module.js: simplify.c
+	emcc \
+		${OPTIMIZE} \
+		--closure 1 \
+		-s WASM=1 \
+		-s ALLOW_MEMORY_GROWTH=1 \
+		-s MODULARIZE=1 \
+		-s EXPORT_ES6=1 \
+		-s EXPORTED_FUNCTIONS='["_simplify", "_malloc", "_free"]' \
+		-o simplify.js \
+		simplify.c
--- a/lib/simplify-wasm/example.html
+++ b/lib/simplify-wasm/example.html
@ -0,0 +1,32 @@
+<html lang="en">
+
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <meta http-equiv="X-UA-Compatible" content="ie=edge">
+    <title>Document</title>
+</head>
+
+<body>
+    <div>Original array: <span id="src">Loading...</span></div>
+    <div>Simplified array: <span id="dest">Loading...</span></div>
+    
+    <script type="module">
+        import moduleFactory from './simplify.js'
+        import { storeCoords, loadResultAndFreeMemory } from '../wasm-util/coordinates.js'
+
+        const module = moduleFactory()
+        const data = [[0, 0], [1, 1], [1, 2], [2, 2], [5, 5], [5, 0], [6, 10], [10, 10]]
+        document.getElementById('src').innerText = JSON.stringify(data)
+
+        module.onRuntimeInitialized = async _ => {
+            const buffer = storeCoords(module, data)
+            const result = module._simplify(buffer, data.length * 2, 2, true)
+            module._free(buffer)
+            const simplified = loadResultAndFreeMemory(module, result)
+            document.getElementById('dest').innerText = JSON.stringify(simplified)
+        }
+    </script>
+</body>
+
+</html>
--- a/lib/simplify-wasm/index.js
+++ b/lib/simplify-wasm/index.js
@ -0,0 +1,31 @@
+/*
+ This file is meant to be processed in the context of an asset bundler. 
+ Specifically the import of 'simplify.wasm' is meant to be resolved by the 
+ corresponding path to that file. Configure a file loader to resolve .wasm 
+ files (e.g. Webpack: file-loader) accordingly.
+ 
+ Otherwise you have to use the module factory 'simplify.js' manually and 
+ reproduce the steps from below to fit your build context. See example.html.
+
+ Other than wrapping the memory handling for convenience this method also makes
+ sure the module is only loaded once.
+*/
+
+import wasmModuleFactory from './simplify.js'
+import wasmUrl from './simplify.wasm'
+import { initEmscriptenModule } from '../wasm-util/initEmscripten.js'
+import { storeCoords, loadResultAndFreeMemory } from '../wasm-util/coordinates.js'
+
+export async function simplifyWasm(coords, tolerance, highestQuality) {
+    const module = await getModule()
+    const buffer = storeCoords(module, coords)
+    const result = module._simplify(buffer, coords.length * 2, tolerance, highestQuality)
+    module._free(buffer)
+    return loadResultAndFreeMemory(module, result) 
+}
+
+let emscriptenModule
+export async function getModule () {
+    if (!emscriptenModule) emscriptenModule = initEmscriptenModule(wasmModuleFactory, wasmUrl)
+    return await emscriptenModule
+}
--- a/lib/simplify-wasm/simplify.c
+++ b/lib/simplify-wasm/simplify.c
@ -0,0 +1,122 @@
+#include <stdlib.h>
+
+#define DIM 2
+
+void copyCoordinate(double* from, double* to) {
+    for (int i = 0; i < DIM; i++) {
+        to[i] = from[i];
+    }
+}
+
+// extends array and copies point on the end. Returns new length
+int push(double* array, int length, double* point) {
+    int newLength = length + DIM;
+    // realloc(array, newLength * sizeof(double));
+    copyCoordinate(point, array + length);
+    return newLength;
+}
+
+// square distance between 2 points
+double getSqDist(double* p1, double* p2) {
+    double dx = p1[0] - p2[0],
+        dy = p1[1] - p2[1];
+    return dx * dx + dy * dy;
+}
+
+
+// square distance from a point to a segment
+double getSqSegDist(double* p, double* p1, double* p2) {
+    double x = p1[0],
+           y = p1[1],
+           dx = p2[0] - x,
+        dy = p2[1] - y;
+
+    if (dx != 0 || dy != 0) {
+        double t = ((p[0] - x) * dx + (p[1] - y) * dy) / (dx * dx + dy * dy);
+
+        if (t > 1) {
+            x = p2[0];
+            y = p2[1];
+
+        } else if (t > 0) {
+            x += dx * t;
+            y += dy * t;
+        }
+    }
+
+    dx = p[0] - x;
+    dy = p[1] - y;
+
+    return dx * dx + dy * dy;
+}
+
+// basic distance-based simplification
+int simplifyRadialDist(double* points, int length, double sqTolerance, double* newPoints) {
+    double* prevPoint = points;
+    double* point;
+    int sizeOfNewPoints = push(newPoints, 0, points);
+
+    for (int i = 1; i < length; i += DIM) {
+        point = points + i;
+        if (getSqDist(point, prevPoint) > sqTolerance) {
+            sizeOfNewPoints = push(newPoints, sizeOfNewPoints, point);
+            prevPoint = point;
+        }
+    }
+
+    if (prevPoint != point) {
+        sizeOfNewPoints = push(newPoints, sizeOfNewPoints, point);
+    }
+
+    return sizeOfNewPoints;
+}
+
+int simplifyDPStep(double* points, int first, int last, double sqTolerance, double* simplified, int lengthOfSimplified) {
+    double maxSqDist = sqTolerance;
+    int index;
+
+    for (int i = first + DIM; i < last; i += DIM) {
+        double sqDist = getSqSegDist(points + i, points + first, points + last);
+
+        if (sqDist > maxSqDist) {
+            index = i;
+            maxSqDist = sqDist;
+        }
+    }
+
+    if (maxSqDist > sqTolerance) {
+        if (index - first > DIM) lengthOfSimplified = simplifyDPStep(points, first, index, sqTolerance, simplified, lengthOfSimplified);
+        lengthOfSimplified = push(simplified, lengthOfSimplified, points + index);
+        if (last - index > DIM) lengthOfSimplified = simplifyDPStep(points, index, last, sqTolerance, simplified, lengthOfSimplified);
+    }
+    return lengthOfSimplified;
+}
+
+// simplification using Ramer-Douglas-Peucker algorithm
+int simplifyDouglasPeucker(double* points, int length, double sqTolerance, double* simplified) {
+    int lengthOfSimplified;
+    lengthOfSimplified = push(simplified, 0, points);
+    lengthOfSimplified = simplifyDPStep(points, 0, length - DIM, sqTolerance, simplified, lengthOfSimplified);
+    lengthOfSimplified = push(simplified, lengthOfSimplified, points + length - DIM);
+    return lengthOfSimplified;
+}
+
+int* simplify(double * input, int length, double tolerance, int highestQuality) {
+    double sqTolerance = tolerance * tolerance;
+    double* points = input;
+    double* resultRdDistance = NULL;
+    double* result = malloc(length * sizeof(double));
+
+    if (!highestQuality) {
+        resultRdDistance = malloc(length * sizeof(double));
+        length = simplifyRadialDist(points, length, sqTolerance, resultRdDistance);
+        points = resultRdDistance;
+    }
+    int resultLength = simplifyDouglasPeucker(points, length, sqTolerance, result);
+    free(resultRdDistance);
+
+    int* resultInfo = malloc(2);
+    resultInfo[0] = (int) result;
+    resultInfo[1] = resultLength;
+    return resultInfo;
+}
--- a/lib/simplify-wasm/simplify.js
+++ b/lib/simplify-wasm/simplify.js
@ -0,0 +1,31 @@
+
+var Module = (function() {
+  var _scriptDir = typeof document !== 'undefined' && document.currentScript ? document.currentScript.src : undefined;
+  return (
+function(Module) {
+  Module = Module || {};
+
+var a;a||(a=typeof Module !== 'undefined' ? Module : {});var f={},g;for(g in a)a.hasOwnProperty(g)&&(f[g]=a[g]);a.arguments=[];a.thisProgram="./this.program";a.quit=function(b,c){throw c;};a.preRun=[];a.postRun=[];var h=!1,k=!1,l=!1,m=!1;h="object"===typeof window;k="function"===typeof importScripts;l="object"===typeof process&&"function"===typeof require&&!h&&!k;m=!h&&!l&&!k;var n="";
+if(l){n=__dirname+"/";var p,q;a.read=function(b,c){p||(p=require("fs"));q||(q=require("path"));b=q.normalize(b);b=p.readFileSync(b);return c?b:b.toString()};a.readBinary=function(b){b=a.read(b,!0);b.buffer||(b=new Uint8Array(b));b.buffer||r("Assertion failed: undefined");return b};1<process.argv.length&&(a.thisProgram=process.argv[1].replace(/\\/g,"/"));a.arguments=process.argv.slice(2);process.on("uncaughtException",function(b){if(!(b instanceof t))throw b;});process.on("unhandledRejection",r);a.quit=
+function(b){process.exit(b)};a.inspect=function(){return"[Emscripten Module object]"}}else if(m)"undefined"!=typeof read&&(a.read=function(b){return read(b)}),a.readBinary=function(b){if("function"===typeof readbuffer)return new Uint8Array(readbuffer(b));b=read(b,"binary");"object"===typeof b||r("Assertion failed: undefined");return b},"undefined"!=typeof scriptArgs?a.arguments=scriptArgs:"undefined"!=typeof arguments&&(a.arguments=arguments),"function"===typeof quit&&(a.quit=function(b){quit(b)});
+else if(h||k)k?n=self.location.href:document.currentScript&&(n=document.currentScript.src),_scriptDir&&(n=_scriptDir),0!==n.indexOf("blob:")?n=n.substr(0,n.lastIndexOf("/")+1):n="",a.read=function(b){var c=new XMLHttpRequest;c.open("GET",b,!1);c.send(null);return c.responseText},k&&(a.readBinary=function(b){var c=new XMLHttpRequest;c.open("GET",b,!1);c.responseType="arraybuffer";c.send(null);return new Uint8Array(c.response)}),a.readAsync=function(b,c,d){var e=new XMLHttpRequest;e.open("GET",b,!0);
+e.responseType="arraybuffer";e.onload=function(){200==e.status||0==e.status&&e.response?c(e.response):d()};e.onerror=d;e.send(null)},a.setWindowTitle=function(b){document.title=b};var u=a.print||("undefined"!==typeof console?console.log.bind(console):"undefined"!==typeof print?print:null),v=a.printErr||("undefined"!==typeof printErr?printErr:"undefined"!==typeof console&&console.warn.bind(console)||u);for(g in f)f.hasOwnProperty(g)&&(a[g]=f[g]);f=void 0;
+var w={"f64-rem":function(b,c){return b%c},"debugger":function(){debugger}};"object"!==typeof WebAssembly&&v("no native wasm support detected");var x,y=!1;"undefined"!==typeof TextDecoder&&new TextDecoder("utf8");"undefined"!==typeof TextDecoder&&new TextDecoder("utf-16le");function z(b){0<b%65536&&(b+=65536-b%65536);return b}var buffer,A,B;
+function C(){a.HEAP8=A=new Int8Array(buffer);a.HEAP16=new Int16Array(buffer);a.HEAP32=B=new Int32Array(buffer);a.HEAPU8=new Uint8Array(buffer);a.HEAPU16=new Uint16Array(buffer);a.HEAPU32=new Uint32Array(buffer);a.HEAPF32=new Float32Array(buffer);a.HEAPF64=new Float64Array(buffer)}var E=a.TOTAL_MEMORY||16777216;5242880>E&&v("TOTAL_MEMORY should be larger than TOTAL_STACK, was "+E+"! (TOTAL_STACK=5242880)");
+a.buffer?buffer=a.buffer:"object"===typeof WebAssembly&&"function"===typeof WebAssembly.Memory?(x=new WebAssembly.Memory({initial:E/65536}),buffer=x.buffer):buffer=new ArrayBuffer(E);C();B[684]=5245648;function F(b){for(;0<b.length;){var c=b.shift();if("function"==typeof c)c();else{var d=c.l;"number"===typeof d?void 0===c.j?a.dynCall_v(d):a.dynCall_vi(d,c.j):d(void 0===c.j?null:c.j)}}}var G=[],H=[],I=[],J=[],K=!1;function L(){var b=a.preRun.shift();G.unshift(b)}var M=0,N=null,O=null;
+a.preloadedImages={};a.preloadedAudios={};function P(){var b=Q;return String.prototype.startsWith?b.startsWith("data:application/octet-stream;base64,"):0===b.indexOf("data:application/octet-stream;base64,")}var Q="simplify.wasm";if(!P()){var R=Q;Q=a.locateFile?a.locateFile(R,n):n+R}function S(){try{if(a.wasmBinary)return new Uint8Array(a.wasmBinary);if(a.readBinary)return a.readBinary(Q);throw"both async and sync fetching of the wasm failed";}catch(b){r(b)}}
+function T(){return a.wasmBinary||!h&&!k||"function"!==typeof fetch?new Promise(function(b){b(S())}):fetch(Q,{credentials:"same-origin"}).then(function(b){if(!b.ok)throw"failed to load wasm binary file at '"+Q+"'";return b.arrayBuffer()}).catch(function(){return S()})}
+function U(b){function c(b){a.asm=b.exports;M--;a.monitorRunDependencies&&a.monitorRunDependencies(M);0==M&&(null!==N&&(clearInterval(N),N=null),O&&(b=O,O=null,b()))}function d(b){c(b.instance)}function e(b){T().then(function(b){return WebAssembly.instantiate(b,D)}).then(b,function(b){v("failed to asynchronously prepare wasm: "+b);r(b)})}var D={env:b,global:{NaN:NaN,Infinity:Infinity},"global.Math":Math,asm2wasm:w};M++;a.monitorRunDependencies&&a.monitorRunDependencies(M);if(a.instantiateWasm)try{return a.instantiateWasm(D,
+c)}catch(Y){return v("Module.instantiateWasm callback failed with error: "+Y),!1}a.wasmBinary||"function"!==typeof WebAssembly.instantiateStreaming||P()||"function"!==typeof fetch?e(d):WebAssembly.instantiateStreaming(fetch(Q,{credentials:"same-origin"}),D).then(d,function(b){v("wasm streaming compile failed: "+b);v("falling back to ArrayBuffer instantiation");e(d)});return{}}
+a.asm=function(b,c){c.memory=x;c.table=new WebAssembly.Table({initial:0,maximum:0,element:"anyfunc"});c.__memory_base=1024;c.__table_base=0;return U(c)};function V(){return A.length}function W(b){b=z(b);var c=buffer.byteLength;try{return-1!==x.grow((b-c)/65536)?(buffer=x.buffer,!0):!1}catch(d){return!1}}
+var X=a.asm({},{b:function(b){a.___errno_location&&(B[a.___errno_location()>>2]=b);return b},e:V,d:function(b){if(2147418112<b)return!1;for(var c=Math.max(V(),16777216);c<b;)536870912>=c?c=z(2*c):c=Math.min(z((3*c+2147483648)/4),2147418112);if(!W(c))return!1;C();return!0},c:function(){r("OOM")},a:2736},buffer);a.asm=X;a.___errno_location=function(){return a.asm.f.apply(null,arguments)};a._free=function(){return a.asm.g.apply(null,arguments)};a._malloc=function(){return a.asm.h.apply(null,arguments)};
+a._simplify=function(){return a.asm.i.apply(null,arguments)};a.asm=X;a.then=function(b){if(a.calledRun)b(a);else{var c=a.onRuntimeInitialized;a.onRuntimeInitialized=function(){c&&c();b(a)}}return a};function t(b){this.name="ExitStatus";this.message="Program terminated with exit("+b+")";this.status=b}t.prototype=Error();t.prototype.constructor=t;O=function aa(){a.calledRun||Z();a.calledRun||(O=aa)};
+function Z(){function b(){if(!a.calledRun&&(a.calledRun=!0,!y)){K||(K=!0,F(H));F(I);if(a.onRuntimeInitialized)a.onRuntimeInitialized();if(a.postRun)for("function"==typeof a.postRun&&(a.postRun=[a.postRun]);a.postRun.length;){var b=a.postRun.shift();J.unshift(b)}F(J)}}if(!(0<M)){if(a.preRun)for("function"==typeof a.preRun&&(a.preRun=[a.preRun]);a.preRun.length;)L();F(G);0<M||a.calledRun||(a.setStatus?(a.setStatus("Running..."),setTimeout(function(){setTimeout(function(){a.setStatus("")},1);b()},1)):
+b())}}a.run=Z;function r(b){if(a.onAbort)a.onAbort(b);void 0!==b?(u(b),v(b),b=JSON.stringify(b)):b="";y=!0;throw"abort("+b+"). Build with -s ASSERTIONS=1 for more info.";}a.abort=r;if(a.preInit)for("function"==typeof a.preInit&&(a.preInit=[a.preInit]);0<a.preInit.length;)a.preInit.pop()();a.noExitRuntime=!0;Z();
+
+
+  return Module
+}
+);
+})();
+export default Module;
--- a/lib/simplify-wasm/simplify.wasm
+++ b/lib/simplify-wasm/simplify.wasm
--- a/lib/turf-simplify/LICENSE
+++ b/lib/turf-simplify/LICENSE
@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2017 TurfJS
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
--- a/lib/turf-simplify/README.md
+++ b/lib/turf-simplify/README.md
@ -0,0 +1,87 @@
+# @turf/simplify
+
+<!-- Generated by documentation.js. Update this documentation by updating the source code. -->
+
+## simplify
+
+Takes a [GeoJSON][1] object and returns a simplified version. Internally uses
+[simplify-js][2] to perform simplification using the Ramer-Douglas-Peucker algorithm.
+
+**Parameters**
+
+-   `geojson` **[GeoJSON][3]** object to be simplified
+-   `options` **[Object][4]** Optional parameters (optional, default `{}`)
+    -   `options.tolerance` **[number][5]** simplification tolerance (optional, default `1`)
+    -   `options.highQuality` **[boolean][6]** whether or not to spend more time to create a higher-quality simplification with a different algorithm (optional, default `false`)
+    -   `options.mutate` **[boolean][6]** allows GeoJSON input to be mutated (significant performance increase if true) (optional, default `false`)
+
+**Examples**
+
+```javascript
+var geojson = turf.polygon([[
+  [-70.603637, -33.399918],
+  [-70.614624, -33.395332],
+  [-70.639343, -33.392466],
+  [-70.659942, -33.394759],
+  [-70.683975, -33.404504],
+  [-70.697021, -33.419406],
+  [-70.701141, -33.434306],
+  [-70.700454, -33.446339],
+  [-70.694274, -33.458369],
+  [-70.682601, -33.465816],
+  [-70.668869, -33.472117],
+  [-70.646209, -33.473835],
+  [-70.624923, -33.472117],
+  [-70.609817, -33.468107],
+  [-70.595397, -33.458369],
+  [-70.587158, -33.442901],
+  [-70.587158, -33.426283],
+  [-70.590591, -33.414248],
+  [-70.594711, -33.406224],
+  [-70.603637, -33.399918]
+]]);
+var options = {tolerance: 0.01, highQuality: false};
+var simplified = turf.simplify(geojson, options);
+
+//addToMap
+var addToMap = [geojson, simplified]
+```
+
+Returns **[GeoJSON][3]** a simplified GeoJSON
+
+[1]: https://tools.ietf.org/html/rfc7946#section-3
+
+[2]: http://mourner.github.io/simplify-js/
+
+[3]: https://tools.ietf.org/html/rfc7946#section-3
+
+[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
+
+[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
+
+[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
+
+<!-- This file is automatically generated. Please don't edit it directly:
+if you find an error, edit the source file (likely index.js), and re-run
+./scripts/generate-readmes in the turf project. -->
+
+---
+
+This module is part of the [Turfjs project](http://turfjs.org/), an open source
+module collection dedicated to geographic algorithms. It is maintained in the
+[Turfjs/turf](https://github.com/Turfjs/turf) repository, where you can create
+PRs and issues.
+
+### Installation
+
+Install this module individually:
+
+```sh
+$ npm install @turf/simplify
+```
+
+Or install the Turf module that includes it as a function:
+
+```sh
+$ npm install @turf/turf
+```
--- a/lib/turf-simplify/bench.js
+++ b/lib/turf-simplify/bench.js
@ -0,0 +1,67 @@
+import fs from 'fs';
+import path from 'path';
+import load from 'load-json-file';
+import Benchmark from 'benchmark';
+import simplify from './';
+
+const directory = path.join(__dirname, 'test', 'in') + path.sep;
+const fixtures = fs.readdirSync(directory).map(filename => {
+    return {
+        name: path.parse(filename).name,
+        geojson: load.sync(directory + filename)
+    };
+});
+
+/**
+ * Single Process Benchmark
+ *
+ * argentina: 4.695ms
+ * featurecollection: 1.647ms
+ * fiji-hiQ: 0.461ms
+ * geometrycollection: 3.332ms
+ * linestring: 0.460ms
+ * multilinestring: 0.657ms
+ * multipoint: 0.193ms
+ * multipolygon: 6.108ms
+ * point: 0.032ms
+ * poly-issue#555-5: 4.956ms
+ * polygon: 0.675ms
+ * simple-polygon: 2.735ms
+ */
+for (const {name, geojson} of fixtures) {
+    let {tolerance, highQuality} = geojson.properties || {};
+    tolerance = tolerance || 0.01;
+    highQuality = highQuality || false;
+    console.time(name);
+    simplify(geojson, tolerance, highQuality);
+    console.timeEnd(name);
+}
+
+/**
+ * Benchmark Results
+ *
+ * argentina x 13,380 ops/sec ±4.31% (72 runs sampled)
+ * featurecollection x 4,709 ops/sec ±2.24% (76 runs sampled)
+ * fiji-hiQ x 41,197 ops/sec ±1.96% (80 runs sampled)
+ * geometrycollection x 4,690 ops/sec ±2.25% (78 runs sampled)
+ * linestring x 29,737 ops/sec ±2.26% (77 runs sampled)
+ * multilinestring x 20,530 ops/sec ±2.08% (77 runs sampled)
+ * multipoint x 394,980 ops/sec ±2.35% (77 runs sampled)
+ * multipolygon x 809 ops/sec ±3.32% (70 runs sampled)
+ * point x 5,157,027 ops/sec ±8.79% (72 runs sampled)
+ * poly-issue#555-5 x 1,816 ops/sec ±2.43% (66 runs sampled)
+ * polygon x 2,996 ops/sec ±2.85% (74 runs sampled)
+ * simple-polygon x 369 ops/sec ±7.55% (66 runs sampled)
+ */
+const suite = new Benchmark.Suite('turf-transform-simplify');
+for (const {name, geojson} of fixtures) {
+    let {tolerance, highQuality} = geojson.properties || {};
+    tolerance = tolerance || 0.01;
+    highQuality = highQuality || false;
+    suite.add(name, () => simplify(geojson, tolerance, highQuality));
+}
+
+suite
+    .on('cycle', e => console.log(String(e.target)))
+    .on('complete', () => {})
+    .run();
--- a/lib/turf-simplify/index.d.ts
+++ b/lib/turf-simplify/index.d.ts
@ -0,0 +1,13 @@
+import { AllGeoJSON } from '@turf/helpers'
+
+/**
+ * http://turfjs.org/docs/#simplify
+ */
+export default function simplify<T extends AllGeoJSON>(
+    geojson: T,
+    options?: {
+        tolerance?: number,
+        highQuality?: boolean,
+        mutate?: boolean
+    }
+): T;
--- a/lib/turf-simplify/index.js
+++ b/lib/turf-simplify/index.js
@ -0,0 +1,175 @@
+import cleanCoords from '@turf/clean-coords';
+import clone from '@turf/clone';
+import { geomEach } from '@turf/meta';
+import { isObject } from '@turf/helpers';
+import simplifyJS from './lib/simplify';
+
+/**
+ * Takes a {@link GeoJSON} object and returns a simplified version. Internally uses
+ * [simplify-js](http://mourner.github.io/simplify-js/) to perform simplification using the Ramer-Douglas-Peucker algorithm.
+ *
+ * @name simplify
+ * @param {GeoJSON} geojson object to be simplified
+ * @param {Object} [options={}] Optional parameters
+ * @param {number} [options.tolerance=1] simplification tolerance
+ * @param {boolean} [options.highQuality=false] whether or not to spend more time to create a higher-quality simplification with a different algorithm
+ * @param {boolean} [options.mutate=false] allows GeoJSON input to be mutated (significant performance increase if true)
+ * @returns {GeoJSON} a simplified GeoJSON
+ * @example
+ * var geojson = turf.polygon([[
+ *   [-70.603637, -33.399918],
+ *   [-70.614624, -33.395332],
+ *   [-70.639343, -33.392466],
+ *   [-70.659942, -33.394759],
+ *   [-70.683975, -33.404504],
+ *   [-70.697021, -33.419406],
+ *   [-70.701141, -33.434306],
+ *   [-70.700454, -33.446339],
+ *   [-70.694274, -33.458369],
+ *   [-70.682601, -33.465816],
+ *   [-70.668869, -33.472117],
+ *   [-70.646209, -33.473835],
+ *   [-70.624923, -33.472117],
+ *   [-70.609817, -33.468107],
+ *   [-70.595397, -33.458369],
+ *   [-70.587158, -33.442901],
+ *   [-70.587158, -33.426283],
+ *   [-70.590591, -33.414248],
+ *   [-70.594711, -33.406224],
+ *   [-70.603637, -33.399918]
+ * ]]);
+ * var options = {tolerance: 0.01, highQuality: false};
+ * var simplified = turf.simplify(geojson, options);
+ *
+ * //addToMap
+ * var addToMap = [geojson, simplified]
+ */
+function simplify(geojson, options) {
+    // Optional parameters
+    options = options || {};
+    if (!isObject(options)) throw new Error('options is invalid');
+    var tolerance = options.tolerance !== undefined ? options.tolerance : 1;
+    var highQuality = options.highQuality || false;
+    var mutate = options.mutate || false;
+
+    if (!geojson) throw new Error('geojson is required');
+    if (tolerance && tolerance < 0) throw new Error('invalid tolerance');
+
+    // Clone geojson to avoid side effects
+    if (mutate !== true) geojson = clone(geojson);
+
+    geomEach(geojson, function (geom) {
+        simplifyGeom(geom, tolerance, highQuality);
+    });
+    return geojson;
+}
+
+/**
+ * Simplifies a feature's coordinates
+ *
+ * @private
+ * @param {Geometry} geometry to be simplified
+ * @param {number} [tolerance=1] simplification tolerance
+ * @param {boolean} [highQuality=false] whether or not to spend more time to create a higher-quality simplification with a different algorithm
+ * @returns {Geometry} output
+ */
+function simplifyGeom(geometry, tolerance, highQuality) {
+    var type = geometry.type;
+
+    // "unsimplyfiable" geometry types
+    if (type === 'Point' || type === 'MultiPoint') return geometry;
+
+    // Remove any extra coordinates
+    cleanCoords(geometry, true);
+
+    var coordinates = geometry.coordinates;
+    switch (type) {
+    case 'LineString':
+        geometry['coordinates'] = simplifyLine(coordinates, tolerance, highQuality);
+        break;
+    case 'MultiLineString':
+        geometry['coordinates'] = coordinates.map(function (lines) {
+            return simplifyLine(lines, tolerance, highQuality);
+        });
+        break;
+    case 'Polygon':
+        geometry['coordinates'] = simplifyPolygon(coordinates, tolerance, highQuality);
+        break;
+    case 'MultiPolygon':
+        geometry['coordinates'] = coordinates.map(function (rings) {
+            return simplifyPolygon(rings, tolerance, highQuality);
+        });
+    }
+    return geometry;
+}
+
+
+/**
+ * Simplifies the coordinates of a LineString with simplify-js
+ *
+ * @private
+ * @param {Array<number>} coordinates to be processed
+ * @param {number} tolerance simplification tolerance
+ * @param {boolean} highQuality whether or not to spend more time to create a higher-quality
+ * @returns {Array<Array<number>>} simplified coords
+ */
+function simplifyLine(coordinates, tolerance, highQuality) {
+    return simplifyJS(coordinates.map(function (coord) {
+        return {x: coord[0], y: coord[1], z: coord[2]};
+    }), tolerance, highQuality).map(function (coords) {
+        return (coords.z) ? [coords.x, coords.y, coords.z] : [coords.x, coords.y];
+    });
+}
+
+
+/**
+ * Simplifies the coordinates of a Polygon with simplify-js
+ *
+ * @private
+ * @param {Array<number>} coordinates to be processed
+ * @param {number} tolerance simplification tolerance
+ * @param {boolean} highQuality whether or not to spend more time to create a higher-quality
+ * @returns {Array<Array<Array<number>>>} simplified coords
+ */
+function simplifyPolygon(coordinates, tolerance, highQuality) {
+    return coordinates.map(function (ring) {
+        var pts = ring.map(function (coord) {
+            return {x: coord[0], y: coord[1]};
+        });
+        if (pts.length < 4) {
+            throw new Error('invalid polygon');
+        }
+        var simpleRing = simplifyJS(pts, tolerance, highQuality).map(function (coords) {
+            return [coords.x, coords.y];
+        });
+        //remove 1 percent of tolerance until enough points to make a triangle
+        while (!checkValidity(simpleRing)) {
+            tolerance -= tolerance * 0.01;
+            simpleRing = simplifyJS(pts, tolerance, highQuality).map(function (coords) {
+                return [coords.x, coords.y];
+            });
+        }
+        if (
+            (simpleRing[simpleRing.length - 1][0] !== simpleRing[0][0]) ||
+            (simpleRing[simpleRing.length - 1][1] !== simpleRing[0][1])) {
+            simpleRing.push(simpleRing[0]);
+        }
+        return simpleRing;
+    });
+}
+
+
+/**
+ * Returns true if ring has at least 3 coordinates and its first coordinate is the same as its last
+ *
+ * @private
+ * @param {Array<number>} ring coordinates to be checked
+ * @returns {boolean} true if valid
+ */
+function checkValidity(ring) {
+    if (ring.length < 3) return false;
+    //if the last point is the same as the first, it's not a triangle
+    return !(ring.length === 3 && ((ring[2][0] === ring[0][0]) && (ring[2][1] === ring[0][1])));
+}
+
+export default simplify;
--- a/lib/turf-simplify/lib/simplify.js
+++ b/lib/turf-simplify/lib/simplify.js
@ -0,0 +1,111 @@
+/*
+ (c) 2013, Vladimir Agafonkin
+ Simplify.js, a high-performance JS polyline simplification library
+ mourner.github.io/simplify-js
+*/
+
+// to suit your point format, run search/replace for '.x' and '.y';
+// for 3D version, see 3d branch (configurability would draw significant performance overhead)
+
+// square distance between 2 points
+function getSqDist(p1, p2) {
+
+    var dx = p1.x - p2.x,
+        dy = p1.y - p2.y;
+
+    return dx * dx + dy * dy;
+}
+
+// square distance from a point to a segment
+function getSqSegDist(p, p1, p2) {
+
+    var x = p1.x,
+        y = p1.y,
+        dx = p2.x - x,
+        dy = p2.y - y;
+
+    if (dx !== 0 || dy !== 0) {
+
+        var t = ((p.x - x) * dx + (p.y - y) * dy) / (dx * dx + dy * dy);
+
+        if (t > 1) {
+            x = p2.x;
+            y = p2.y;
+
+        } else if (t > 0) {
+            x += dx * t;
+            y += dy * t;
+        }
+    }
+
+    dx = p.x - x;
+    dy = p.y - y;
+
+    return dx * dx + dy * dy;
+}
+// rest of the code doesn't care about point format
+
+// basic distance-based simplification
+function simplifyRadialDist(points, sqTolerance) {
+
+    var prevPoint = points[0],
+        newPoints = [prevPoint],
+        point;
+
+    for (var i = 1, len = points.length; i < len; i++) {
+        point = points[i];
+
+        if (getSqDist(point, prevPoint) > sqTolerance) {
+            newPoints.push(point);
+            prevPoint = point;
+        }
+    }
+
+    if (prevPoint !== point) newPoints.push(point);
+
+    return newPoints;
+}
+
+function simplifyDPStep(points, first, last, sqTolerance, simplified) {
+    var maxSqDist = sqTolerance,
+        index;
+
+    for (var i = first + 1; i < last; i++) {
+        var sqDist = getSqSegDist(points[i], points[first], points[last]);
+
+        if (sqDist > maxSqDist) {
+            index = i;
+            maxSqDist = sqDist;
+        }
+    }
+
+    if (maxSqDist > sqTolerance) {
+        if (index - first > 1) simplifyDPStep(points, first, index, sqTolerance, simplified);
+        simplified.push(points[index]);
+        if (last - index > 1) simplifyDPStep(points, index, last, sqTolerance, simplified);
+    }
+}
+
+// simplification using Ramer-Douglas-Peucker algorithm
+function simplifyDouglasPeucker(points, sqTolerance) {
+    var last = points.length - 1;
+
+    var simplified = [points[0]];
+    simplifyDPStep(points, 0, last, sqTolerance, simplified);
+    simplified.push(points[last]);
+
+    return simplified;
+}
+
+// both algorithms combined for awesome performance
+export default function simplify(points, tolerance, highestQuality) {
+
+    if (points.length <= 2) return points;
+
+    var sqTolerance = tolerance !== undefined ? tolerance * tolerance : 1;
+
+    points = highestQuality ? points : simplifyRadialDist(points, sqTolerance);
+    points = simplifyDouglasPeucker(points, sqTolerance);
+
+    return points;
+}
--- a/lib/turf-simplify/package.json
+++ b/lib/turf-simplify/package.json
@ -0,0 +1,63 @@
+{
+  "name": "@turf/simplify",
+  "version": "5.1.5",
+  "description": "turf simplify module",
+  "main": "main.js",
+  "module": "main.es.js",
+  "types": "index.d.ts",
+  "files": [
+    "index.js",
+    "index.d.ts",
+    "main.js",
+    "lib",
+    "main.es.js"
+  ],
+  "scripts": {
+    "pretest": "rollup -c ../../rollup.config.js",
+    "test": "node -r @std/esm test.js",
+    "posttest": "node -r @std/esm ../../scripts/validate-es5-dependencies.js",
+    "bench": "node -r @std/esm bench.js",
+    "docs": "node ../../scripts/generate-readmes"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/Turfjs/turf.git"
+  },
+  "keywords": [
+    "turf",
+    "gis",
+    "simplify",
+    "Ramer-Douglas-Peucker",
+    "algorithm",
+    "peucker"
+  ],
+  "author": "Turf Authors",
+  "contributors": [
+    "Vladimir Agafonkin <@mourner>",
+    "Stefano Borghi <@stebogit>"
+  ],
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/Turfjs/turf/issues"
+  },
+  "homepage": "https://github.com/Turfjs/turf",
+  "devDependencies": {
+    "@std/esm": "*",
+    "@turf/truncate": "6.x",
+    "benchmark": "*",
+    "load-json-file": "*",
+    "rollup": "*",
+    "tape": "*",
+    "write-json-file": "*"
+  },
+  "dependencies": {
+    "@turf/clean-coords": "^5.1.5",
+    "@turf/clone": "6.x",
+    "@turf/helpers": "6.x",
+    "@turf/meta": "6.x"
+  },
+  "@std/esm": {
+    "esm": "js",
+    "cjs": true
+  }
+}
--- a/lib/turf-simplify/test.js
+++ b/lib/turf-simplify/test.js
@ -0,0 +1,86 @@
+import fs from 'fs';
+import test from 'tape';
+import path from 'path';
+import load from 'load-json-file';
+import write from 'write-json-file';
+import truncate from '@turf/truncate';
+import { polygon, multiPolygon } from '@turf/helpers';
+import simplify from '.';
+
+const directories = {
+    in: path.join(__dirname, 'test', 'in') + path.sep,
+    out: path.join(__dirname, 'test', 'out') + path.sep
+};
+
+let fixtures = fs.readdirSync(directories.in).map(filename => {
+    return {
+        filename,
+        name: path.parse(filename).name,
+        geojson: load.sync(directories.in + filename)
+    };
+});
+// fixtures = fixtures.filter(({name}) => name.includes('#555'));
+
+test('simplify', t => {
+    for (const {filename, name, geojson} of fixtures) {
+        let {tolerance, highQuality} = geojson.properties || {};
+        tolerance = tolerance || 0.01;
+        highQuality = highQuality || false;
+
+        const simplified = truncate(simplify(geojson, {
+            tolerance: tolerance,
+            highQuality: highQuality
+        }));
+
+        if (process.env.REGEN) write.sync(directories.out + filename, simplified);
+        t.deepEqual(simplified, load.sync(directories.out + filename), name);
+    }
+
+    t.end();
+});
+
+
+test('simplify -- throw', t => {
+    const poly = polygon([[[0, 0], [2, 2], [2, 0], [0, 0]]]);
+    t.throws(() => simplify(null), /geojson is required/, 'missing geojson');
+    t.throws(() => simplify(poly, {tolerance: -1}), /invalid tolerance/, 'negative tolerance');
+    t.end();
+});
+
+
+test('simplify -- removes ID & BBox from properties', t => {
+    const properties = {foo: 'bar'};
+    const id = 12345;
+    const bbox = [0, 0, 2, 2];
+    const poly = polygon([[[0, 0], [2, 2], [2, 0], [0, 0]]], properties, {bbox, id});
+    const simple = simplify(poly, {tolerance: 0.1});
+
+    t.equal(simple.id, id);
+    t.deepEqual(simple.bbox, bbox);
+    t.deepEqual(simple.properties, properties);
+    t.end();
+});
+
+
+test('simplify -- issue #555', t => {
+    // polygons from issue #555
+    const poly1 = polygon([[[-75.693254, 45.431144], [-75.693335, 45.431109], [-75.693335, 45.431109], [-75.693254, 45.431144]]]);
+    const poly2 = polygon([[[-75.627178, 45.438106], [-75.627179, 45.438106], [-75.62718, 45.438106], [-75.627178, 45.438106]]]);
+    const poly3 = polygon([[[-75.684722, 45.410083], [-75.684641, 45.409989], [-75.684641, 45.409989], [-75.684722, 45.410083], [-75.684722, 45.410083]]]);
+    const poly4 = polygon([[[-75.885634, 45.272762], [-75.885482, 45.272641], [-75.885554, 45.272596], [-75.885534, 45.272581], [-75.885581, 45.272551], [-75.885703, 45.272647], [-75.885706, 45.272645], [-75.885709, 45.272647], [-75.885767, 45.272693], [-75.885759, 45.272698], [-75.885716, 45.272728], [-75.885716, 45.272728], [-75.885712, 45.272731], [-75.885712, 45.272731], [-75.885708, 45.272734], [-75.885684, 45.272749], [-75.885671, 45.272739], [-75.885634, 45.272762]], [[-75.885708, 45.27273], [-75.885708, 45.272729], [-75.885708, 45.272729], [-75.885708, 45.27273]]]);
+    const options = {tolerance: 0.000001, highQuality: true};
+
+    t.throws(() => simplify(poly1, options), /invalid polygon/);
+    t.throws(() => simplify(poly2, options), /invalid polygon/);
+    t.throws(() => simplify(poly3, options), /invalid polygon/);
+    t.throws(() => simplify(poly4, options), /invalid polygon/);
+    t.end();
+});
+
+test('simplify -- issue #918', t => {
+    // simplify hangs on this input #918
+    t.throws(() => simplify(multiPolygon([[[[0, 90], [0, 90], [0, 90], [0, 90], [0, 90], [0, 90], [0, 90], [0, 90], [0, 90], [0, 90], [0, 90]]]])), /invalid polygon/, 'invalid polygon');
+    t.throws(() => simplify(multiPolygon([[[[0, 1], [0, 2], [0, 3], [0, 2.5], [0, 1]]]])), /invalid polygon/, 'invalid polygon');
+    t.throws(() => simplify(multiPolygon([[[[0, 1], [0, 1], [1, 2], [0, 1]]]])), /invalid polygon/, 'invalid polygon');
+    t.end();
+});
--- a/lib/turf-simplify/test/in/argentina.geojson
+++ b/lib/turf-simplify/test/in/argentina.geojson
@ -0,0 +1,455 @@
+{
+	"type": "Feature",
+	"id": "ARG",
+	"properties": {
+		"tolerance": 0.1,
+		"name": "Argentina"
+	},
+	"geometry": {
+		"type": "Polygon",
+		"coordinates": [
+			[
+				[
+					-64.964892,
+					-22.075862
+				],
+				[
+					-64.377021,
+					-22.798091
+				],
+				[
+					-63.986838,
+					-21.993644
+				],
+				[
+					-62.846468,
+					-22.034985
+				],
+				[
+					-62.685057,
+					-22.249029
+				],
+				[
+					-60.846565,
+					-23.880713
+				],
+				[
+					-60.028966,
+					-24.032796
+				],
+				[
+					-58.807128,
+					-24.771459
+				],
+				[
+					-57.777217,
+					-25.16234
+				],
+				[
+					-57.63366,
+					-25.603657
+				],
+				[
+					-58.618174,
+					-27.123719
+				],
+				[
+					-57.60976,
+					-27.395899
+				],
+				[
+					-56.486702,
+					-27.548499
+				],
+				[
+					-55.695846,
+					-27.387837
+				],
+				[
+					-54.788795,
+					-26.621786
+				],
+				[
+					-54.625291,
+					-25.739255
+				],
+				[
+					-54.13005,
+					-25.547639
+				],
+				[
+					-53.628349,
+					-26.124865
+				],
+				[
+					-53.648735,
+					-26.923473
+				],
+				[
+					-54.490725,
+					-27.474757
+				],
+				[
+					-55.162286,
+					-27.881915
+				],
+				[
+					-56.2909,
+					-28.852761
+				],
+				[
+					-57.625133,
+					-30.216295
+				],
+				[
+					-57.874937,
+					-31.016556
+				],
+				[
+					-58.14244,
+					-32.044504
+				],
+				[
+					-58.132648,
+					-33.040567
+				],
+				[
+					-58.349611,
+					-33.263189
+				],
+				[
+					-58.427074,
+					-33.909454
+				],
+				[
+					-58.495442,
+					-34.43149
+				],
+				[
+					-57.22583,
+					-35.288027
+				],
+				[
+					-57.362359,
+					-35.97739
+				],
+				[
+					-56.737487,
+					-36.413126
+				],
+				[
+					-56.788285,
+					-36.901572
+				],
+				[
+					-57.749157,
+					-38.183871
+				],
+				[
+					-59.231857,
+					-38.72022
+				],
+				[
+					-61.237445,
+					-38.928425
+				],
+				[
+					-62.335957,
+					-38.827707
+				],
+				[
+					-62.125763,
+					-39.424105
+				],
+				[
+					-62.330531,
+					-40.172586
+				],
+				[
+					-62.145994,
+					-40.676897
+				],
+				[
+					-62.745803,
+					-41.028761
+				],
+				[
+					-63.770495,
+					-41.166789
+				],
+				[
+					-64.73209,
+					-40.802677
+				],
+				[
+					-65.118035,
+					-41.064315
+				],
+				[
+					-64.978561,
+					-42.058001
+				],
+				[
+					-64.303408,
+					-42.359016
+				],
+				[
+					-63.755948,
+					-42.043687
+				],
+				[
+					-63.458059,
+					-42.563138
+				],
+				[
+					-64.378804,
+					-42.873558
+				],
+				[
+					-65.181804,
+					-43.495381
+				],
+				[
+					-65.328823,
+					-44.501366
+				],
+				[
+					-65.565269,
+					-45.036786
+				],
+				[
+					-66.509966,
+					-45.039628
+				],
+				[
+					-67.293794,
+					-45.551896
+				],
+				[
+					-67.580546,
+					-46.301773
+				],
+				[
+					-66.597066,
+					-47.033925
+				],
+				[
+					-65.641027,
+					-47.236135
+				],
+				[
+					-65.985088,
+					-48.133289
+				],
+				[
+					-67.166179,
+					-48.697337
+				],
+				[
+					-67.816088,
+					-49.869669
+				],
+				[
+					-68.728745,
+					-50.264218
+				],
+				[
+					-69.138539,
+					-50.73251
+				],
+				[
+					-68.815561,
+					-51.771104
+				],
+				[
+					-68.149995,
+					-52.349983
+				],
+				[
+					-68.571545,
+					-52.299444
+				],
+				[
+					-69.498362,
+					-52.142761
+				],
+				[
+					-71.914804,
+					-52.009022
+				],
+				[
+					-72.329404,
+					-51.425956
+				],
+				[
+					-72.309974,
+					-50.67701
+				],
+				[
+					-72.975747,
+					-50.74145
+				],
+				[
+					-73.328051,
+					-50.378785
+				],
+				[
+					-73.415436,
+					-49.318436
+				],
+				[
+					-72.648247,
+					-48.878618
+				],
+				[
+					-72.331161,
+					-48.244238
+				],
+				[
+					-72.447355,
+					-47.738533
+				],
+				[
+					-71.917258,
+					-46.884838
+				],
+				[
+					-71.552009,
+					-45.560733
+				],
+				[
+					-71.659316,
+					-44.973689
+				],
+				[
+					-71.222779,
+					-44.784243
+				],
+				[
+					-71.329801,
+					-44.407522
+				],
+				[
+					-71.793623,
+					-44.207172
+				],
+				[
+					-71.464056,
+					-43.787611
+				],
+				[
+					-71.915424,
+					-43.408565
+				],
+				[
+					-72.148898,
+					-42.254888
+				],
+				[
+					-71.746804,
+					-42.051386
+				],
+				[
+					-71.915734,
+					-40.832339
+				],
+				[
+					-71.680761,
+					-39.808164
+				],
+				[
+					-71.413517,
+					-38.916022
+				],
+				[
+					-70.814664,
+					-38.552995
+				],
+				[
+					-71.118625,
+					-37.576827
+				],
+				[
+					-71.121881,
+					-36.658124
+				],
+				[
+					-70.364769,
+					-36.005089
+				],
+				[
+					-70.388049,
+					-35.169688
+				],
+				[
+					-69.817309,
+					-34.193571
+				],
+				[
+					-69.814777,
+					-33.273886
+				],
+				[
+					-70.074399,
+					-33.09121
+				],
+				[
+					-70.535069,
+					-31.36501
+				],
+				[
+					-69.919008,
+					-30.336339
+				],
+				[
+					-70.01355,
+					-29.367923
+				],
+				[
+					-69.65613,
+					-28.459141
+				],
+				[
+					-69.001235,
+					-27.521214
+				],
+				[
+					-68.295542,
+					-26.89934
+				],
+				[
+					-68.5948,
+					-26.506909
+				],
+				[
+					-68.386001,
+					-26.185016
+				],
+				[
+					-68.417653,
+					-24.518555
+				],
+				[
+					-67.328443,
+					-24.025303
+				],
+				[
+					-66.985234,
+					-22.986349
+				],
+				[
+					-67.106674,
+					-22.735925
+				],
+				[
+					-66.273339,
+					-21.83231
+				],
+				[
+					-64.964892,
+					-22.075862
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/in/featurecollection.geojson
+++ b/lib/turf-simplify/test/in/featurecollection.geojson
@ -0,0 +1,388 @@
+{
+	"type": "FeatureCollection",
+	"properties": {
+		"tolerance": 0.01
+	},
+	"features": [
+		{
+			"type": "Feature",
+			"properties": {
+				"id": 1
+			},
+			"geometry": {
+				"type": "LineString",
+				"coordinates": [
+					[
+						27.977542877197266,
+						-26.17500493262446
+					],
+					[
+						27.975482940673828,
+						-26.17870225771557
+					],
+					[
+						27.969818115234375,
+						-26.177931991326645
+					],
+					[
+						27.967071533203125,
+						-26.177623883345735
+					],
+					[
+						27.966899871826172,
+						-26.1810130263384
+					],
+					[
+						27.967758178710938,
+						-26.1853263385099
+					],
+					[
+						27.97290802001953,
+						-26.1853263385099
+					],
+					[
+						27.97496795654297,
+						-26.18270756087535
+					],
+					[
+						27.97840118408203,
+						-26.1810130263384
+					],
+					[
+						27.98011779785156,
+						-26.183323749143113
+					],
+					[
+						27.98011779785156,
+						-26.18655868408986
+					],
+					[
+						27.978744506835938,
+						-26.18933141398614
+					],
+					[
+						27.97496795654297,
+						-26.19025564262006
+					],
+					[
+						27.97119140625,
+						-26.19040968001282
+					],
+					[
+						27.969303131103516,
+						-26.1899475672235
+					],
+					[
+						27.96741485595703,
+						-26.189639491012183
+					],
+					[
+						27.9656982421875,
+						-26.187945057286793
+					],
+					[
+						27.965354919433594,
+						-26.18563442612686
+					],
+					[
+						27.96432495117187,
+						-26.183015655416536
+					]
+				]
+			}
+		},
+		{
+			"type": "Feature",
+			"properties": {
+				"id": 2
+			},
+			"geometry": {
+				"type": "Polygon",
+				"coordinates": [
+					[
+						[
+							27.972049713134762,
+							-26.199035448897074
+						],
+						[
+							27.9741096496582,
+							-26.196108920345292
+						],
+						[
+							27.977371215820312,
+							-26.197495179879635
+						],
+						[
+							27.978572845458984,
+							-26.20042167359348
+						],
+						[
+							27.980976104736328,
+							-26.200729721284862
+						],
+						[
+							27.982349395751953,
+							-26.197803235312957
+						],
+						[
+							27.982177734375,
+							-26.194414580727656
+						],
+						[
+							27.982177734375,
+							-26.19256618212382
+						],
+						[
+							27.98406600952148,
+							-26.192258112838022
+						],
+						[
+							27.985267639160156,
+							-26.191950042737417
+						],
+						[
+							27.986125946044922,
+							-26.19426054863105
+						],
+						[
+							27.986984252929688,
+							-26.196416979445644
+						],
+						[
+							27.987327575683594,
+							-26.198881422912123
+						],
+						[
+							27.98715591430664,
+							-26.201345814222698
+						],
+						[
+							27.985095977783203,
+							-26.20381015337393
+						],
+						[
+							27.983036041259766,
+							-26.20550435628209
+						],
+						[
+							27.979946136474606,
+							-26.20550435628209
+						],
+						[
+							27.97719955444336,
+							-26.20488828535003
+						],
+						[
+							27.97445297241211,
+							-26.203656133705152
+						],
+						[
+							27.972564697265625,
+							-26.201961903900578
+						],
+						[
+							27.972049713134762,
+							-26.199035448897074
+						]
+					]
+				]
+			}
+		},
+		{
+			"type": "Feature",
+			"properties": {
+				"id": 3
+			},
+			"geometry": {
+				"type": "Polygon",
+				"coordinates": [
+					[
+						[
+							27.946643829345703,
+							-26.170845301716803
+						],
+						[
+							27.94269561767578,
+							-26.183631842055114
+						],
+						[
+							27.935657501220703,
+							-26.183323749143113
+						],
+						[
+							27.92741775512695,
+							-26.17685360983018
+						],
+						[
+							27.926902770996094,
+							-26.171153427614488
+						],
+						[
+							27.928619384765625,
+							-26.165298896316028
+						],
+						[
+							27.936859130859375,
+							-26.161292995018652
+						],
+						[
+							27.94509887695312,
+							-26.158981835530525
+						],
+						[
+							27.950420379638672,
+							-26.161601146157146
+						],
+						[
+							27.951793670654297,
+							-26.166223315536712
+						],
+						[
+							27.954025268554688,
+							-26.173464345889972
+						],
+						[
+							27.954025268554688,
+							-26.179626570662702
+						],
+						[
+							27.951278686523438,
+							-26.187945057286793
+						],
+						[
+							27.944583892822266,
+							-26.19395248382672
+						],
+						[
+							27.936172485351562,
+							-26.194876675795218
+						],
+						[
+							27.930850982666016,
+							-26.19379845111899
+						],
+						[
+							27.925701141357422,
+							-26.190563717201886
+						],
+						[
+							27.92278289794922,
+							-26.18655868408986
+						],
+						[
+							27.92072296142578,
+							-26.180858976522302
+						],
+						[
+							27.917118072509766,
+							-26.174080583026957
+						],
+						[
+							27.916603088378906,
+							-26.16683959094609
+						],
+						[
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--- a/lib/turf-simplify/test/in/fiji-hiQ.geojson
+++ b/lib/turf-simplify/test/in/fiji-hiQ.geojson
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+}
--- a/lib/turf-simplify/test/in/geometrycollection.geojson
+++ b/lib/turf-simplify/test/in/geometrycollection.geojson
@ -0,0 +1,364 @@
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+}
--- a/lib/turf-simplify/test/in/issue-#1144.geojson
+++ b/lib/turf-simplify/test/in/issue-#1144.geojson
@ -0,0 +1,91 @@
+{
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+}
--- a/lib/turf-simplify/test/in/linestring.geojson
+++ b/lib/turf-simplify/test/in/linestring.geojson
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--- a/lib/turf-simplify/test/in/multilinestring.geojson
+++ b/lib/turf-simplify/test/in/multilinestring.geojson
@ -0,0 +1,413 @@
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+}
--- a/lib/turf-simplify/test/in/multipoint.geojson
+++ b/lib/turf-simplify/test/in/multipoint.geojson
@ -0,0 +1,11 @@
+{
+	"type": "Feature",
+	"properties": {},
+	"geometry": {
+		"type": "MultiPoint",
+		"coordinates":[[
+			0,
+			0
+		],[ 1,2]]
+	}
+}
--- a/lib/turf-simplify/test/in/multipolygon.geojson
+++ b/lib/turf-simplify/test/in/multipolygon.geojson
--- a/lib/turf-simplify/test/in/point.geojson
+++ b/lib/turf-simplify/test/in/point.geojson
@ -0,0 +1,11 @@
+{
+	"type": "Feature",
+	"properties": {},
+	"geometry": {
+		"type": "Point",
+		"coordinates": [
+			5,
+			1
+		]
+	}
+}
--- a/lib/turf-simplify/test/in/poly-issue#555-5.geojson
+++ b/lib/turf-simplify/test/in/poly-issue#555-5.geojson
@ -0,0 +1,183 @@
+{
+	"type": "Feature",
+	"properties": {
+		"tolerance": 0.00005
+	},
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+}
--- a/lib/turf-simplify/test/in/polygon.geojson
+++ b/lib/turf-simplify/test/in/polygon.geojson
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--- a/lib/turf-simplify/test/in/simple-polygon.geojson
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+				[
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+		]
+	}
+}
--- a/lib/turf-simplify/test/out/argentina.geojson
+++ b/lib/turf-simplify/test/out/argentina.geojson
@ -0,0 +1,419 @@
+{
+	"type": "Feature",
+	"id": "ARG",
+	"properties": {
+		"tolerance": 0.1,
+		"name": "Argentina"
+	},
+	"geometry": {
+		"type": "Polygon",
+		"coordinates": [
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+					-22.075862
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/featurecollection.geojson
+++ b/lib/turf-simplify/test/out/featurecollection.geojson
@ -0,0 +1,136 @@
+{
+	"type": "FeatureCollection",
+	"properties": {
+		"tolerance": 0.01
+	},
+	"features": [
+		{
+			"type": "Feature",
+			"properties": {
+				"id": 1
+			},
+			"geometry": {
+				"type": "LineString",
+				"coordinates": [
+					[
+						27.977543,
+						-26.175005
+					],
+					[
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+						-26.183016
+					]
+				]
+			}
+		},
+		{
+			"type": "Feature",
+			"properties": {
+				"id": 2
+			},
+			"geometry": {
+				"type": "Polygon",
+				"coordinates": [
+					[
+						[
+							27.97205,
+							-26.199035
+						],
+						[
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+						],
+						[
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+							-26.199035
+						]
+					]
+				]
+			}
+		},
+		{
+			"type": "Feature",
+			"properties": {
+				"id": 3
+			},
+			"geometry": {
+				"type": "Polygon",
+				"coordinates": [
+					[
+						[
+							27.946644,
+							-26.170845
+						],
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+						],
+						[
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+					],
+					[
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+						[
+							27.934971,
+							-26.173927
+						],
+						[
+							27.941494,
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+						],
+						[
+							27.936859,
+							-26.165915
+						]
+					]
+				]
+			}
+		},
+		{
+			"type": "Feature",
+			"properties": {
+				"id": 4
+			},
+			"geometry": {
+				"type": "Point",
+				"coordinates": [
+					27.956429,
+					-26.15251
+				]
+			}
+		}
+	]
+}
--- a/lib/turf-simplify/test/out/fiji-hiQ.geojson
+++ b/lib/turf-simplify/test/out/fiji-hiQ.geojson
@ -0,0 +1,70 @@
+{
+	"type": "Feature",
+	"properties": {
+		"tolerance": 0.005,
+		"highQuality": true
+	},
+	"geometry": {
+		"type": "Polygon",
+		"coordinates": [
+			[
+				[
+					179.975281,
+					-16.51477
+				],
+				[
+					179.980431,
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+				],
+				[
+					180.0103,
+					-16.523328
+				],
+				[
+					180.007553,
+					-16.534848
+				],
+				[
+					180.018196,
+					-16.539127
+				],
+				[
+					180.061455,
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+				],
+				[
+					180.066605,
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+				],
+				[
+					180.046349,
+					-16.479547
+				],
+				[
+					180.086861,
+					-16.44761
+				],
+				[
+					180.084114,
+					-16.441354
+				],
+				[
+					180.055618,
+					-16.439707
+				],
+				[
+					180.026093,
+					-16.464732
+				],
+				[
+					180.01442,
+					-16.464073
+				],
+				[
+					179.975281,
+					-16.51477
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/geometrycollection.geojson
+++ b/lib/turf-simplify/test/out/geometrycollection.geojson
@ -0,0 +1,109 @@
+{
+	"type": "GeometryCollection",
+	"geometries": [
+		{
+			"type": "LineString",
+			"coordinates": [
+				[
+					27.977543,
+					-26.175005
+				],
+				[
+					27.964325,
+					-26.183016
+				]
+			]
+		},
+		{
+			"type": "Polygon",
+			"coordinates": [
+				[
+					[
+						27.97205,
+						-26.199035
+					],
+					[
+						27.984066,
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+					],
+					[
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+						-26.201346
+					],
+					[
+						27.97205,
+						-26.199035
+					]
+				]
+			]
+		},
+		{
+			"type": "Polygon",
+			"coordinates": [
+				[
+					[
+						27.946644,
+						-26.170845
+					],
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+					],
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+					]
+				],
+				[
+					[
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+					],
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+					],
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+						-26.170075
+					],
+					[
+						27.936859,
+						-26.165915
+					]
+				]
+			]
+		},
+		{
+			"type": "Point",
+			"coordinates": [
+				27.956429,
+				-26.15251
+			]
+		}
+	]
+}
--- a/lib/turf-simplify/test/out/issue-#1144.geojson
+++ b/lib/turf-simplify/test/out/issue-#1144.geojson
@ -0,0 +1,43 @@
+{
+	"type": "Feature",
+	"properties": {},
+	"geometry": {
+		"type": "Polygon",
+		"coordinates": [
+			[
+				[
+					-70.603637,
+					-33.399918
+				],
+				[
+					-70.683975,
+					-33.404504
+				],
+				[
+					-70.701141,
+					-33.434306
+				],
+				[
+					-70.694274,
+					-33.458369
+				],
+				[
+					-70.668869,
+					-33.472117
+				],
+				[
+					-70.609817,
+					-33.468107
+				],
+				[
+					-70.587158,
+					-33.442901
+				],
+				[
+					-70.603637,
+					-33.399918
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/linestring.geojson
+++ b/lib/turf-simplify/test/out/linestring.geojson
@ -0,0 +1,105 @@
+{
+	"type": "Feature",
+	"properties": {},
+	"geometry": {
+		"type": "LineString",
+		"coordinates": [
+			[
+				-80.513992,
+				28.069557
+			],
+			[
+				-80.48584,
+				28.042289
+			],
+			[
+				-80.505753,
+				28.028349
+			],
+			[
+				-80.476913,
+				28.021075
+			],
+			[
+				-80.49202,
+				27.998039
+			],
+			[
+				-80.4673,
+				27.962263
+			],
+			[
+				-80.46524,
+				27.9198
+			],
+			[
+				-80.405502,
+				27.930114
+			],
+			[
+				-80.396576,
+				27.980456
+			],
+			[
+				-80.429535,
+				27.990764
+			],
+			[
+				-80.414429,
+				28.009558
+			],
+			[
+				-80.359497,
+				27.972572
+			],
+			[
+				-80.382156,
+				27.913733
+			],
+			[
+				-80.417862,
+				27.88157
+			],
+			[
+				-80.393829,
+				27.854254
+			],
+			[
+				-80.368423,
+				27.888246
+			],
+			[
+				-80.354691,
+				27.868824
+			],
+			[
+				-80.359497,
+				27.842112
+			],
+			[
+				-80.399323,
+				27.82511
+			],
+			[
+				-80.400696,
+				27.793528
+			],
+			[
+				-80.361557,
+				27.786846
+			],
+			[
+				-80.359325,
+				27.806853
+			],
+			[
+				-80.354991,
+				27.796831
+			],
+			[
+				-80.328727,
+				27.808485
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/multilinestring.geojson
+++ b/lib/turf-simplify/test/out/multilinestring.geojson
@ -0,0 +1,169 @@
+{
+	"type": "Feature",
+	"properties": {},
+	"geometry": {
+		"type": "MultiLineString",
+		"coordinates": [
+			[
+				[
+					-80.513992,
+					28.069557
+				],
+				[
+					-80.48584,
+					28.042289
+				],
+				[
+					-80.505753,
+					28.028349
+				],
+				[
+					-80.476913,
+					28.021075
+				],
+				[
+					-80.49202,
+					27.998039
+				],
+				[
+					-80.4673,
+					27.962263
+				],
+				[
+					-80.46524,
+					27.9198
+				],
+				[
+					-80.405502,
+					27.930114
+				],
+				[
+					-80.396576,
+					27.980456
+				],
+				[
+					-80.429535,
+					27.990764
+				],
+				[
+					-80.414429,
+					28.009558
+				],
+				[
+					-80.359497,
+					27.972572
+				],
+				[
+					-80.382156,
+					27.913733
+				],
+				[
+					-80.417862,
+					27.88157
+				],
+				[
+					-80.393829,
+					27.854254
+				],
+				[
+					-80.368423,
+					27.888246
+				],
+				[
+					-80.354691,
+					27.868824
+				],
+				[
+					-80.359497,
+					27.842112
+				],
+				[
+					-80.399323,
+					27.82511
+				],
+				[
+					-80.400696,
+					27.793528
+				],
+				[
+					-80.361557,
+					27.786846
+				],
+				[
+					-80.359325,
+					27.806853
+				],
+				[
+					-80.354991,
+					27.796831
+				],
+				[
+					-80.328727,
+					27.808485
+				]
+			],
+			[
+				[
+					-80.511932,
+					28.091366
+				],
+				[
+					-80.4776,
+					28.074404
+				],
+				[
+					-80.46936,
+					28.010164
+				],
+				[
+					-80.454254,
+					27.996827
+				],
+				[
+					-80.444641,
+					28.029561
+				],
+				[
+					-80.355377,
+					27.991976
+				],
+				[
+					-80.348511,
+					27.947099
+				],
+				[
+					-80.323792,
+					27.937394
+				],
+				[
+					-80.340271,
+					27.879142
+				],
+				[
+					-80.352631,
+					27.909486
+				],
+				[
+					-80.367737,
+					27.858504
+				],
+				[
+					-80.340271,
+					27.822074
+				],
+				[
+					-80.292206,
+					27.853647
+				],
+				[
+					-80.303192,
+					27.860932
+				],
+				[
+					-80.293579,
+					27.894922
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/multipoint.geojson
+++ b/lib/turf-simplify/test/out/multipoint.geojson
@ -0,0 +1,17 @@
+{
+	"type": "Feature",
+	"properties": {},
+	"geometry": {
+		"type": "MultiPoint",
+		"coordinates": [
+			[
+				0,
+				0
+			],
+			[
+				1,
+				2
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/multipolygon.geojson
+++ b/lib/turf-simplify/test/out/multipolygon.geojson
@ -0,0 +1,88 @@
+{
+	"type": "Feature",
+	"properties": {
+		"country": "South Africa",
+		"tolerance": 0.01
+	},
+	"geometry": {
+		"type": "MultiPolygon",
+		"coordinates": [
+			[
+				[
+					[
+						19.41807,
+						-34.68668
+					],
+					[
+						19.41455,
+						-34.68997
+					],
+					[
+						19.40993,
+						-34.68798
+					],
+					[
+						19.41807,
+						-34.68668
+					]
+				]
+			],
+			[
+				[
+					[
+						19.4188,
+						-34.67816
+					],
+					[
+						19.42342,
+						-34.68024
+					],
+					[
+						19.41508,
+						-34.68598
+					],
+					[
+						19.4188,
+						-34.67816
+					]
+				]
+			],
+			[
+				[
+					[
+						19.45629,
+						-34.39274
+					],
+					[
+						19.55599,
+						-34.38974
+					],
+					[
+						19.68811,
+						-34.76532
+					],
+					[
+						19.67762,
+						-34.78188
+					],
+					[
+						19.63818,
+						-34.77916
+					],
+					[
+						19.59412,
+						-34.73309
+					],
+					[
+						19.49554,
+						-34.67162
+					],
+					[
+						19.45629,
+						-34.39274
+					]
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/point.geojson
+++ b/lib/turf-simplify/test/out/point.geojson
@ -0,0 +1,11 @@
+{
+	"type": "Feature",
+	"properties": {},
+	"geometry": {
+		"type": "Point",
+		"coordinates": [
+			5,
+			1
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/poly-issue#555-5.geojson
+++ b/lib/turf-simplify/test/out/poly-issue#555-5.geojson
@ -0,0 +1,59 @@
+{
+	"type": "Feature",
+	"properties": {
+		"tolerance": 0.00005
+	},
+	"geometry": {
+		"type": "Polygon",
+		"coordinates": [
+			[
+				[
+					-75.788024,
+					45.345283
+				],
+				[
+					-75.787931,
+					45.345237
+				],
+				[
+					-75.787975,
+					45.345143
+				],
+				[
+					-75.787855,
+					45.345099
+				],
+				[
+					-75.788023,
+					45.345028
+				],
+				[
+					-75.78814,
+					45.345236
+				],
+				[
+					-75.788024,
+					45.345283
+				]
+			],
+			[
+				[
+					-75.787933,
+					45.345065
+				],
+				[
+					-75.78793,
+					45.34506
+				],
+				[
+					-75.78793,
+					45.345066
+				],
+				[
+					-75.787933,
+					45.345065
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/polygon.geojson
+++ b/lib/turf-simplify/test/out/polygon.geojson
@ -0,0 +1,30 @@
+{
+	"type": "Feature",
+	"properties": {
+		"tolerance": 1,
+		"elevation": 25
+	},
+	"geometry": {
+		"type": "Polygon",
+		"coordinates": [
+			[
+				[
+					-75.51527,
+					39.11245
+				],
+				[
+					-75.142602,
+					39.875538
+				],
+				[
+					-75.813087,
+					39.904921
+				],
+				[
+					-75.51527,
+					39.11245
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/test/out/simple-polygon.geojson
+++ b/lib/turf-simplify/test/out/simple-polygon.geojson
@ -0,0 +1,29 @@
+{
+	"type": "Feature",
+	"properties": {
+		"tolerance": 100
+	},
+	"geometry": {
+		"type": "Polygon",
+		"coordinates": [
+			[
+				[
+					26.14843,
+					-28.297552
+				],
+				[
+					26.150354,
+					-28.302606
+				],
+				[
+					26.135463,
+					-28.304283
+				],
+				[
+					26.14843,
+					-28.297552
+				]
+			]
+		]
+	}
+}
--- a/lib/turf-simplify/types.ts
+++ b/lib/turf-simplify/types.ts
@ -0,0 +1,11 @@
+import {polygon, Feature, Polygon} from '@turf/helpers'
+import simplify from './'
+
+const poly = polygon([[[0, 0], [10, 10], [20, 20], [0, 0]]]);
+
+// Output type is the same as Input type
+const simple: Feature<Polygon> = simplify(poly);
+
+// Extra params
+simplify(poly, {tolerance: 1});
+simplify(poly, {tolerance: 1, highQuality: true});
--- a/lib/wasm-util/README.md
+++ b/lib/wasm-util/README.md
@ -0,0 +1 @@
+Utility function for handling emscripten modules and transfering arrays to and from module memory.
--- a/lib/wasm-util/coordinates.js
+++ b/lib/wasm-util/coordinates.js
@ -0,0 +1,62 @@
+/*
+ Utility functions to store and load coordinates to and from module memory
+ Coordinates are assumed to be an array of coordinate pairs ([[x1,y1], [x2,y2], [x3,y3]])
+*/
+
+/**
+ * Allocate memory for coordinates and stores them in a flat representation.
+ * Returns a pointer to the buffer. The length of the buffer is coords.length * 2
+ * @param {*} module 
+ * @param {Array} coords - An array of coordinate pairs
+ */
+export function storeCoords(module, coords) {
+  const buffer = module._malloc(coords.length * 2 * 8)
+  const heap = new Float64Array(module.HEAPF64.buffer, buffer, coords.length * 2)
+  for (let i = 0; i < coords.length; i++) {
+      heap[2*i] = coords[i][0]
+      heap[2*i + 1] = coords[i][1]
+  }
+  return buffer
+}
+
+/**
+ * Loads coordinates from the memory by the result pointer.
+ * Frees the resultpointer and the result before returning
+ * @param {*} module 
+ * @param {*} result - pointer to Uint32 array of length 2. Stores the resultPointer and resultLength
+ */
+export function loadResultAndFreeMemory(module, result) {
+  const [resultPointer, resultLength] = new Uint32Array(module.HEAPU32.buffer, result, 2)
+  const simplified = new Float64Array(module.HEAPF64.buffer, resultPointer, resultLength)
+  const coords = unflattenCoords(simplified)
+  module._free(result)
+  module._free(resultPointer)
+  return coords
+}
+
+/**
+ * Loads coordinates from the memory by the result pointer without freeing memory.
+ * For benchmarking purposes
+ * @param {*} module 
+ * @param {*} result - pointer to Uint32 array of length 2. Stores the resultPointer and resultLength
+ */
+export function loadResult(module, result) {
+  const [resultPointer, resultLength] = new Uint32Array(module.HEAPU32.buffer, result, 2)
+  const simplified = new Float64Array(module.HEAPF64.buffer, resultPointer, resultLength)
+  return unflattenCoords(simplified)
+}
+
+/**
+ * Transforms a flat array to an array coordinate pairs
+ * @param {Array} flattened - length must be even
+ */
+export function unflattenCoords (flattened) {
+  const coords = []
+  let x, y
+  for (let i = 0; i < flattened.length; i += 2) {
+      x = flattened[i]
+      y = flattened[i + 1]
+      coords.push([x, y])
+  }
+  return coords
+}
--- a/lib/wasm-util/initEmscripten.js
+++ b/lib/wasm-util/initEmscripten.js
@ -0,0 +1,28 @@
+/**
+ * Promisify emscripten modules
+ * 
+ * idea taken from squoosh app: https://raw.githubusercontent.com/GoogleChromeLabs/squoosh/master/src/codecs/util.ts
+ * 
+ * usage: 
+ * // create a global variable to store the initialized module once
+ * let emscriptenModule
+ * 
+ * // inside an async function:
+ * // use the global as cache to the module or initialize it
+ * if (!emscriptenModule) emscriptenModule = initEmscriptenModule(importedGlueCode, urlToWasmFile)
+ * const module = await emscriptenModule
+ */
+export function initEmscriptenModule(moduleFactory, wasmUrl) {
+  return new Promise (resolve => {
+      const module = moduleFactory({
+          noInitialRun: true,
+          locateFile: (url) => wasmUrl ? wasmUrl : url, 
+          onRuntimeInitialized () {
+              // hack: deleting then breaks an infinite loop
+              // https://github.com/emscripten-core/emscripten/issues/5820
+              delete module.then
+              resolve(module)
+          }
+      })
+  })
+}
--- a/scripts/bundle-size.sh
+++ b/scripts/bundle-size.sh
@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+# Prints the size of a file + gzipped size
+
+human_print(){
+while read B dummy; do
+  [ $B -lt 1024 ] && echo ${B} bytes && break
+  KB=$(((B+512)/1024))
+  [ $KB -lt 1024 ] && echo ${KB} kilobytes && break
+  MB=$(((KB+512)/1024))
+  [ $MB -lt 1024 ] && echo ${MB} megabytes && break
+  GB=$(((MB+512)/1024))
+  [ $GB -lt 1024 ] && echo ${GB} gigabytes && break
+  echo $(((GB+512)/1024)) terabytes
+done
+}
+
+export FILE_NAME=$1
+
+export UNCOMPRESSED_FILE_SIZE=`wc -c < $FILE_NAME`
+export GZIPPED_FILE_SIZE=`gzip -c < $FILE_NAME | wc -c`
+
+echo "Bundle size: $(echo $UNCOMPRESSED_FILE_SIZE | human_print)"
+echo "gzipped size: $(echo $GZIPPED_FILE_SIZE | human_print)"
+echo
+echo "Machine readable:"
+echo "BUNDLE_SIZE: $UNCOMPRESSED_FILE_SIZE,$GZIPPED_FILE_SIZE"
--- a/Show More
+++ b/Show More
				`@ -0,0 +1 @@`
				`export const data = [[0, 0], [1, 1], [1, 2], [2, 2], [5, 5], [5, 0], [6, 10], [10, 10]]`
				`@ -0,0 +1 @@`
				`This is an alternative Simplify.js version to take coordinates as a nested array.`
				`@ -0,0 +1 @@`
				`Utility function for handling emscripten modules and transfering arrays to and from module memory.`