Ported to ES6

.gitignore

@@ -1,3 +1,7 @@
+### Output files
+simplify.js
+simplify.min.js
+
 ### Node template
 # Logs
 logs

bench/bench.js

@@ -1,12 +1,11 @@
+import { Suite } from 'benchmark';
+import simplify from '../index.js';
 
-var Benchmark = require('benchmark');
-var simplify = require('../simplify');
-
-var points = require('../test/fixtures/1k.json');
+import points from '../test/fixtures/1k.json';
 
 console.log('Benchmarking simplify on ' + points.length + ' points...');
 
-new Benchmark.Suite()
+new Suite()
 .add('simplify (HQ)', function() {
     simplify(points, 1, true);
 })

simplify.js → index.js

@@ -4,15 +4,14 @@
  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,
+    const dx = p1.x - p2.x,
         dy = p1.y - p2.y;
 
     return dx * dx + dy * dy;
@@ -21,14 +20,14 @@ function getSqDist(p1, p2) {
 // square distance from a point to a segment
 function getSqSegDist(p, p1, p2) {
 
-    var x = p1.x,
+    let 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);
+        const t = ((p.x - x) * dx + (p.y - y) * dy) / (dx * dx + dy * dy);
 
         if (t > 1) {
             x = p2.x;
@@ -50,11 +49,11 @@ function getSqSegDist(p, p1, p2) {
 // basic distance-based simplification
 function simplifyRadialDist(points, sqTolerance) {
 
-    var prevPoint = points[0],
-        newPoints = [prevPoint],
+    let prevPoint = points[0],
         point;
+    const newPoints = [prevPoint];
 
-    for (var i = 1, len = points.length; i < len; i++) {
+    for (let i = 1, len = points.length; i < len; i++) {
         point = points[i];
 
         if (getSqDist(point, prevPoint) > sqTolerance) {
@@ -69,11 +68,11 @@ function simplifyRadialDist(points, sqTolerance) {
 }
 
 function simplifyDPStep(points, first, last, sqTolerance, simplified) {
-    var maxSqDist = sqTolerance,
+    let maxSqDist = sqTolerance,
         index;
 
-    for (var i = first + 1; i < last; i++) {
-        var sqDist = getSqSegDist(points[i], points[first], points[last]);
+    for (let i = first + 1; i < last; i++) {
+        const sqDist = getSqSegDist(points[i], points[first], points[last]);
 
         if (sqDist > maxSqDist) {
             index = i;
@@ -90,34 +89,24 @@ function simplifyDPStep(points, first, last, sqTolerance, simplified) {
 
 // simplification using Ramer-Douglas-Peucker algorithm
 function simplifyDouglasPeucker(points, sqTolerance) {
-    var last = points.length - 1;
+    const last = points.length - 1;
 
-    var simplified = [points[0]];
+    const 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) {
+export default function simplify(points, tolerance, highestQuality) {
 
     if (points.length <= 2) return points;
 
-    var sqTolerance = tolerance !== undefined ? tolerance * tolerance : 1;
+    const 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;
-
-})();

package.json

@@ -16,23 +16,33 @@
     "url": "git://github.com/mourner/simplify-js.git"
   },
   "main": "simplify.js",
+  "module": "index.js",
   "files": [
     "index.d.ts",
-    "simplify.js"
+    "index.js",
+    "simplify.js",
+    "simplify.min.js"
   ],
   "types": "index.d.ts",
   "devDependencies": {
     "benchmark": "^2.1.4",
+    "eslint": "^6.0.1",
+    "eslint-config-mourner": "^3.0.0",
+    "esm": "^3.2.25",
     "faucet": "0.0.1",
-    "jshint": "^2.9.5",
+    "rollup": "^1.17.0",
+    "rollup-plugin-buble": "^0.19.8",
+    "rollup-plugin-node-resolve": "^5.2.0",
+    "rollup-plugin-terser": "^5.1.1",
     "tape": "^4.8.0"
   },
   "scripts": {
-    "test": "jshint simplify.js test/test.js && node test/test.js | faucet"
+    "build": "rollup -c",
+    "pretest": "eslint index.js test/test.js",
+    "test": "tape -r esm test/test.js | faucet",
+    "perf": "node -r esm bench/bench.js"
   },
-  "jshintConfig": {
-    "quotmark": "single",
-    "trailing": true,
-    "unused": true
+  "eslintConfig": {
+    "extends": "mourner"
   }
 }

rollup.config.js

@@ -0,0 +1,18 @@
+import resolve from 'rollup-plugin-node-resolve';
+import buble from 'rollup-plugin-buble';
+import {terser} from 'rollup-plugin-terser'
+
+const output = (file, plugins) => ({
+    input: 'index.js',
+    output: {
+        name: 'simplify',
+        format: 'umd',
+        file
+    },
+    plugins
+});
+
+export default [
+    output('simplify.js', [resolve(), buble()]),
+    output('simplify.min.js', [resolve(), terser(), buble()])
+];

test/test.js

@@ -1,60 +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}
+const 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}
+const 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');
+import simplify from '../index.js';
+import t from 'tape';
 
-t('simplifies points correctly with the given tolerance', function (t) {
-    var result = simplify(points, 5);
+t('simplifies points correctly with the given tolerance', (t) => {
+    const 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('just return the points if it has only one point', (t) => {
+    const 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('just return the points if it has no points', (t) => {
+    const result = simplify([]);
     t.same(result, []);
     t.end();
 });