refactor Demo.init

demo/js/Demo.js

@@ -31,52 +31,30 @@
             Inspector = MatterTools.Inspector;
     }
 
-    // initialise the demo
+    Demo.create = function(options) {
-
+        var defaults = {
-    Demo.create = function() {
+            sceneName: 'mixed',
-        return {
-            isMobile: _isMobile,
             sceneEvents: []
         };
+
+        return Common.extend(defaults, options);
     };
 
     Demo.init = function() {
         var demo = Demo.create();
 
-        // some example engine options
+        // get container element for the canvas
-        var options = {
+        demo.container = document.getElementById('canvas-container');
-            positionIterations: 6,
-            velocityIterations: 4,
-            enableSleeping: false,
-            metrics: { extended: true }
-        };
 
-        // create a Matter engine
+        // create an example engine (see /examples/engine.js)
-        // NOTE: this is actually Matter.Engine.create(), see the aliases at top of this file
+        demo.engine = Example.engine(demo);
-        if (_isBrowser) {
-            var container = document.getElementById('canvas-container');
-            demo.engine = Engine.create(container, options);
-
-            // add a mouse controlled constraint
-            demo.mouseConstraint = MouseConstraint.create(demo.engine);
-            World.add(demo.engine.world, demo.mouseConstraint);
-        } else {
-            demo.engine = Engine.create(options);
-            demo.engine.render = {};
-            demo.engine.render.options = {};
-        }
-
-        // demo instance reference for external use
-        Matter.Demo._demo = demo;
-
-        // skip runner when performing automated tests
-        if (_isAutomatedTest) return;
 
         // run the engine
         demo.runner = Engine.run(demo.engine);
 
-        // default scene function name
+        // add a mouse controlled constraint
-        demo.sceneName = 'mixed';
+        demo.mouseConstraint = MouseConstraint.create(demo.engine);
+        World.add(demo.engine.world, demo.mouseConstraint);
 
         // get the scene function name from hash
         if (window.location.hash.length !== 0) 
@@ -88,18 +66,20 @@
 
         // set up demo interface (see end of this file)
         Demo.initControls(demo);
+
+        return demo;
     };
 
     // call init when the page has loaded fully
-    
+    if (!_isAutomatedTest) {
         if (window.addEventListener) {
             window.addEventListener('load', Demo.init);
         } else if (window.attachEvent) {
             window.attachEvent('load', Demo.init);
         }
+    }
 
     // the functions for the demo interface and controls below
-
     Demo.initControls = function(demo) {
         var demoSelect = document.getElementById('demo-select'),
             demoReset = document.getElementById('demo-reset');

examples/engine.js

@@ -0,0 +1,17 @@
+(function() {
+
+    var Engine = Matter.Engine;
+
+    Example.engine = function(demo) {
+        // some example engine options
+        var options = {
+            positionIterations: 6,
+            velocityIterations: 4,
+            enableSleeping: false,
+            metrics: { extended: true }
+        };
+
+        return Engine.create(demo.container, options);
+    };
+
+})();

examples/wreckingBall.js

@@ -25,12 +25,6 @@
             pointA: { x: 300, y: 100 },
             bodyB: ball
         }));
-        
-        if (!demo.isMobile) {
-            var renderOptions = engine.render.options;
-            renderOptions.showCollisions = true;
-            renderOptions.showVelocity = true;
-        }
     };
 
 })();

test/browser/TestDemo.js

@@ -51,18 +51,30 @@ var test = function(status) {
             worldEndDiffPath = diffsPath + '/' + demo + '/' + demo + '-' + frames + '.json';
 
         var worldStart = page.evaluate(function(demo) {
-            var engine = Matter.Demo._demo.engine;
             if (!(demo in Matter.Example)) {
                 throw '\'' + demo + '\' is not defined in Matter.Demo';
             }
-            Matter.Demo.reset(Matter.Demo._demo);
+
-            Matter.Example[demo](Matter.Demo._demo);
+            var _demo = Matter.Demo.create(),
+                engine = Matter.Example.engine(_demo),
+                runner = Matter.Runner.create();
+
+            Matter.Demo._demo = _demo;
+            _demo.engine = engine;
+            _demo.engine.render = {};
+            _demo.engine.render.options = {};
+            _demo.runner = runner;
+            _demo.mouseConstraint = Matter.MouseConstraint.create(engine);
+
+            Matter.Demo.reset(_demo);
+            Matter.Example[demo](_demo);
+
             return engine.world;
         }, demo);
 
         var worldEnd = page.evaluate(function(demo, frames) {
             var engine = Matter.Demo._demo.engine,
-                runner = Matter.Runner.create();
+                runner = Matter.Demo._demo.runner;
 
             for (var j = 0; j <= frames; j += 1) {
                 Matter.Runner.tick(runner, engine, j * runner.delta);

test/node/TestDemo.js

@@ -6,8 +6,8 @@ var compare = require('fast-json-patch').compare;
 var path = require('path');
 var $ = require('cheerio');
 var Matter = require('../../build/matter-dev.js');
-Matter.Demo = require('../../demo/js/Demo.js');
 Matter.Example = require('../../demo/js/Examples.js');
+Matter.Demo = require('../../demo/js/Demo.js');
 
 var demo,
     frames = 10,
@@ -42,17 +42,21 @@ var test = function() {
             worldStartDiffPath = diffsPath + '/' + demo + '/' + demo + '-0.json',
             worldEndDiffPath = diffsPath + '/' + demo + '/' + demo + '-' + frames + '.json';
 
-        Matter.Demo.init();
+        var _demo = Matter.Demo.create(),
-
+            engine = Matter.Example.engine(_demo),
-        var engine = Matter.Demo._demo.engine,
             runner = Matter.Runner.create();
 
+        _demo.engine = engine;
+        _demo.engine.render = {};
+        _demo.engine.render.options = {};
+        _demo.runner = runner;
+
         if (!(demo in Matter.Example)) {
             throw '\'' + demo + '\' is not defined in Matter.Example';
         }
 
-        Matter.Demo.reset(Matter.Demo._demo);
+        Matter.Demo.reset(_demo);
-        Matter.Example[demo](Matter.Demo._demo);
+        Matter.Example[demo](_demo);
 
         var worldStart = JSON.parse(resurrect.stringify(engine.world, precisionLimiter));