Merge branch 'browser-tests'

.gitignore

@@ -6,3 +6,4 @@ matter-doc-theme
 build/matter-dev.js
 build/matter-dev.min.js
 demo/js/lib/matter-dev.js
+tests/browser/diffs

.jshintrc

@@ -31,8 +31,8 @@
     "undef": true,
     "-W079": true,            // Silence redefinition errors (they are false positives).
     "predef": [
-        "Matter", "window", "document", "Element", "MatterTools", "PIXI", 
-        "$", "Image", "navigator", "setTimeout", "decomp", "HTMLElement",
+        "Matter", "window", "document", "Element", "MatterTools", "PIXI", "phantom",
+        "$", "Image", "navigator", "setTimeout", "decomp", "HTMLElement", "require",
         "Body", "Composite", "World", "Contact", "Detector", "Grid", 
         "Pairs", "Pair", "Resolver", "SAT", "Constraint", "MouseConstraint", 
         "Common", "Engine", "Mouse", "Sleeping", "Bodies", "Composites", 

.travis.yml

@@ -1,6 +1,11 @@
 language: node_js
+sudo: false
 node_js:
   - "0.10"
-before_install: npm install -g grunt-cli
+before_install: 
+  - npm install -g grunt-cli
+  - mkdir travis-phantomjs
+  - wget https://s3.amazonaws.com/travis-phantomjs/phantomjs-2.0.0-ubuntu-12.04.tar.bz2 -O $PWD/travis-phantomjs/phantomjs-2.0.0-ubuntu-12.04.tar.bz2
+  - tar -xvf $PWD/travis-phantomjs/phantomjs-2.0.0-ubuntu-12.04.tar.bz2 -C $PWD/travis-phantomjs
+  - export PATH=$PWD/travis-phantomjs:$PATH
 install: npm install
-before_script: grunt

Gruntfile.js

@@ -57,7 +57,7 @@ module.exports = function(grunt) {
       options: {
         jshintrc: '.jshintrc'
       },
-      all: ['src/**/*.js', 'demo/js/*.js', '!src/module/*']
+      all: ['src/**/*.js', 'demo/js/*.js', 'test/browser/TestDemo.js', '!src/module/*']
     },
     connect: {
       watch: {
@@ -66,6 +66,11 @@ module.exports = function(grunt) {
           open: 'http://localhost:9000/demo/dev.html',
           livereload: 9001
         }
+      },
+      serve: {
+        options: {
+          port: 9000
+        }
       }
     },
     watch: {
@@ -107,6 +112,19 @@ module.exports = function(grunt) {
         src: 'build/<%= buildName %>.js',
         dest: 'build/<%= buildName %>.js'
       }
+    },
+    shell: {
+      testDemo: {
+        command: function(arg) {
+          arg = arg ? ' --' + arg : '';
+          return 'phantomjs test/browser/TestDemo.js' + arg;
+        },
+        options: {
+          execOptions: {
+            timeout: 1000 * 60
+          }
+        }
+      }
     }
   });
 
@@ -118,11 +136,26 @@ module.exports = function(grunt) {
   grunt.loadNpmTasks('grunt-contrib-copy');
   grunt.loadNpmTasks('grunt-contrib-yuidoc');
   grunt.loadNpmTasks('grunt-preprocess');
+  grunt.loadNpmTasks('grunt-shell');
 
   grunt.registerTask('default', ['test', 'build']);
-  grunt.registerTask('test', ['jshint']);
+  grunt.registerTask('test', ['jshint', 'test:demo']);
+  grunt.registerTask('test:all', ['build:dev', 'connect:serve', 'test']);
   grunt.registerTask('dev', ['build:dev', 'connect:watch', 'watch']);
 
+  grunt.registerTask('test:demo', function() {
+    var updateAll = grunt.option('updateAll'),
+        diff = grunt.option('diff');
+
+    if (updateAll) {
+      grunt.task.run('shell:testDemo:updateAll');
+    } else if (diff) {
+      grunt.task.run('shell:testDemo:diff');
+    } else {
+      grunt.task.run('shell:testDemo');
+    }
+  });
+
   grunt.registerTask('build', function(mode) {
     var isDev = (mode === 'dev'),
         isRelease = (mode === 'release'),

demo/js/Demo.js

@@ -25,6 +25,7 @@
     }
 
     var Demo = {};
+    Matter.Demo = Demo;
 
     var _engine,
         _gui,
@@ -1608,6 +1609,9 @@
         var demoSelect = document.getElementById('demo-select'),
             demoReset = document.getElementById('demo-reset');
 
+        // engine reference for external use
+        Matter.Demo._engine = _engine;
+
         // create a Matter.Gui
         if (!_isMobile && Gui) {
             _gui = Gui.create(_engine);

package.json

@@ -20,6 +20,7 @@
     "rigid body physics"
   ],
   "devDependencies": {
+    "fast-json-patch": "^0.5.4",
     "grunt": "~0.4.2",
     "grunt-contrib-concat": "~0.3.0",
     "grunt-contrib-connect": "~0.6.0",
@@ -28,11 +29,12 @@
     "grunt-contrib-uglify": "~0.2.7",
     "grunt-contrib-watch": "~0.5.3",
     "grunt-contrib-yuidoc": "~0.5.1",
-    "grunt-preprocess": "^4.1.0"
+    "grunt-preprocess": "^4.1.0",
+    "grunt-shell": "^1.1.2"
   },
   "scripts": {
     "dev": "npm install && grunt dev",
-    "test": "grunt test"
+    "test": "grunt test:all"
   },
   "dependencies": {}
 }

test/browser/TestDemo.js

@@ -0,0 +1,184 @@
+var page = require('webpage').create();
+var fs = require('fs');
+var Resurrect = require('./lib/resurrect');
+var compare = require('fast-json-patch').compare;
+var system = require('system');
+
+var demo,
+    frames = 10,
+    testUrl = 'http://localhost:9000/demo/dev.html',
+    refsPath = 'test/browser/refs',
+    diffsPath = 'test/browser/diffs';
+
+var update = arg('--update'),
+    updateAll = typeof arg('--updateAll') !== 'undefined',
+    diff = arg('--diff');
+
+var resurrect = new Resurrect({ cleanup: true }),
+    created = [],
+    changed = [];
+
+var test = function(status) {
+    if (status === 'fail') {
+        console.log('failed to load', testUrl);
+        console.log('check dev server is running!');
+        console.log('use `grunt dev`');
+        phantom.exit(1);
+        return;
+    }
+
+    var demos = page.evaluate(function() {
+        var demoSelect = document.getElementById('demo-select'),
+            options = Array.prototype.slice.call(demoSelect);
+        return options.map(function(o) { return o.value; });
+    });
+
+    fs.removeTree(diffsPath);
+
+    if (diff) {
+        fs.makeDirectory(diffsPath);
+    }
+
+    for (var i = 0; i < demos.length; i += 1) {
+        demo = demos[i];
+
+        var hasChanged = false,
+            hasCreated = false,
+            forceUpdate = update === demo || updateAll,
+            worldStartPath = refsPath + '/' + demo + '/' + demo + '-0.json',
+            worldEndPath = refsPath + '/' + demo + '/' + demo + '-' + frames + '.json',
+            worldStartDiffPath = diffsPath + '/' + demo + '/' + demo + '-0.json',
+            worldEndDiffPath = diffsPath + '/' + demo + '/' + demo + '-' + frames + '.json';
+
+        var worldStart = page.evaluate(function(demo) {
+            var engine = Matter.Demo._engine;
+            Matter.Runner.stop(engine);
+            if (!(demo in Matter.Demo)) {
+                throw '\'' + demo + '\' is not defined in Matter.Demo';
+            }
+            Matter.Demo[demo]();
+            return engine.world;
+        }, demo);
+
+        var worldEnd = page.evaluate(function(demo, frames) {
+            var engine = Matter.Demo._engine;
+
+            for (var j = 0; j <= frames; j += 1) {
+                Matter.Events.trigger(engine, 'tick', { timestamp: engine.timing.timestamp });
+                Matter.Engine.update(engine, engine.timing.delta);
+                Matter.Events.trigger(engine, 'afterTick', { timestamp: engine.timing.timestamp });
+            }
+
+            return engine.world;
+        }, demo, frames);
+
+        if (fs.exists(worldStartPath)) {
+            var worldStartRef = resurrect.resurrect(fs.read(worldStartPath));
+            var worldStartDiff = compare(worldStartRef, worldStart);
+
+            if (worldStartDiff.length !== 0) {
+                if (diff) {
+                    fs.write(worldStartDiffPath, JSON.stringify(worldStartDiff, null, 2), 'w');
+                }
+
+                if (forceUpdate) {
+                    hasCreated = true;
+                    fs.write(worldStartPath, resurrect.stringify(worldStart, null, 2), 'w');
+                } else {
+                    hasChanged = true; 
+                }
+            }
+        } else {
+            hasCreated = true;
+            fs.write(worldStartPath, resurrect.stringify(worldStart, null, 2), 'w');
+        }
+
+        if (fs.exists(worldEndPath)) {
+            var worldEndRef = resurrect.resurrect(fs.read(worldEndPath));
+            var worldEndDiff = compare(worldEndRef, worldEnd);
+
+            if (worldEndDiff.length !== 0) {
+                if (diff) {
+                    fs.write(worldEndDiffPath, JSON.stringify(worldEndDiff, null, 2), 'w');
+                }
+
+                if (forceUpdate) {
+                    hasCreated = true;
+                    fs.write(worldEndPath, resurrect.stringify(worldEnd, null, 2), 'w');
+                } else {
+                    hasChanged = true;
+                }
+            }
+        } else {
+            hasCreated = true;
+            fs.write(worldEndPath, resurrect.stringify(worldEnd, null, 2), 'w');
+        }
+
+        if (hasChanged) {
+            changed.push("'" + demo + "'");
+            system.stdout.write('x');
+        } else if (hasCreated) {
+            created.push("'" + demo + "'");
+            system.stdout.write('+');
+        } else {
+            system.stdout.write('.');
+        }
+    }
+
+    if (created.length > 0) {
+        console.log('\nupdated', created.join(', '));
+    }
+
+    var isOk = changed.length === 0 ? 1 : 0;
+
+    console.log('');
+
+    if (isOk) {
+        console.log('ok');
+    } else {
+        console.log('\nchanges detected on:');
+        console.log(changed.join(', '));
+        console.log('\nreview, then --update [name] or --updateAll');
+        console.log('use --diff for diff log');
+    }
+
+    phantom.exit(!isOk);
+};
+
+function arg(name) {
+    var index = system.args.indexOf(name);
+    if (index >= 0) {
+        return system.args[index + 1] || true;
+    }
+    return undefined;
+}
+
+page.onError = function(msg, trace) {
+    setTimeout(function() {
+        var msgStack = ['testing \'' + demo + '\'', msg];
+
+        if (trace && trace.length) {
+            trace.forEach(function(t) {
+                msgStack.push(' -> ' + (t.file || t.sourceURL) + ': ' + t.line + (t.function ? ' (fn: ' + t.function +')' : ''));
+            });
+        }
+
+        console.log(msgStack.join('\n'));
+        phantom.exit(1);
+    }, 0);
+};
+
+
+page.onResourceReceived = function(res) {
+    setTimeout(function() {
+        if (res.stage === 'end'
+            && (res.status !== 304 && res.status !== 200 && res.status !== null)) {
+            console.log('error', res.status, res.url);
+            phantom.exit(1);
+        }
+    }, 0);
+};
+
+phantom.onError = page.onError;
+
+page.open(testUrl, test);

test/browser/lib/resurrect.js

@@ -0,0 +1,542 @@
+/**
+ * # ResurrectJS
+ * @version 1.0.3
+ * @license Public Domain
+ *
+ * ResurrectJS preserves object behavior (prototypes) and reference
+ * circularity with a special JSON encoding. Unlike regular JSON,
+ * Date, RegExp, DOM objects, and `undefined` are also properly
+ * preserved.
+ *
+ * ## Examples
+ *
+ * function Foo() {}
+ * Foo.prototype.greet = function() { return "hello"; };
+ *
+ * // Behavior is preserved:
+ * var necromancer = new Resurrect();
+ * var json = necromancer.stringify(new Foo());
+ * var foo = necromancer.resurrect(json);
+ * foo.greet();  // => "hello"
+ *
+ * // References to the same object are preserved:
+ * json = necromancer.stringify([foo, foo]);
+ * var array = necromancer.resurrect(json);
+ * array[0] === array[1];  // => true
+ * array[1].greet();  // => "hello"
+ *
+ * // Dates are restored properly
+ * json = necromancer.stringify(new Date());
+ * var date = necromancer.resurrect(json);
+ * Object.prototype.toString.call(date);  // => "[object Date]"
+ *
+ * ## Options
+ *
+ * Options are provided to the constructor as an object with these
+ * properties:
+ *
+ *   prefix ('#'): A prefix string used for temporary properties added
+ *     to objects during serialization and deserialization. It is
+ *     important that you don't use any properties beginning with this
+ *     string. This option must be consistent between both
+ *     serialization and deserialization.
+ *
+ *   cleanup (false): Perform full property cleanup after both
+ *     serialization and deserialization using the `delete`
+ *     operator. This may cause performance penalties (breaking hidden
+ *     classes in V8) on objects that ResurrectJS touches, so enable
+ *     with care.
+ *
+ *   revive (true): Restore behavior (__proto__) to objects that have
+ *     been resurrected. If this is set to false during serialization,
+ *     resurrection information will not be encoded. You still get
+ *     circularity and Date support.
+ *
+ *   resolver (Resurrect.NamespaceResolver(window)): Converts between
+ *     a name and a prototype. Create a custom resolver if your
+ *     constructors are not stored in global variables. The resolver
+ *     has two methods: getName(object) and getPrototype(string).
+ *
+ * For example,
+ *
+ * var necromancer = new Resurrect({
+ *     prefix: '__#',
+ *     cleanup: true
+ * });
+ *
+ * ## Caveats
+ *
+ *   * With the default resolver, all constructors must be named and
+ *   stored in the global variable under that name. This is required
+ *   so that the prototypes can be looked up and reconnected at
+ *   resurrection time.
+ *
+ *   * The wrapper objects Boolean, String, and Number will be
+ *   unwrapped. This means extra properties added to these objects
+ *   will not be preserved.
+ *
+ *   * Functions cannot ever be serialized. Resurrect will throw an
+ *   error if a function is found when traversing a data structure.
+ *
+ * @see http://nullprogram.com/blog/2013/03/28/
+ */
+
+/**
+ * @param {Object} [options] See options documentation.
+ * @namespace
+ * @constructor
+ */
+function Resurrect(options) {
+    this.table = null;
+    this.prefix = '#';
+    this.cleanup = false;
+    this.revive = true;
+    for (var option in options) {
+        if (options.hasOwnProperty(option)) {
+            this[option] = options[option];
+        }
+    }
+    this.refcode = this.prefix + 'id';
+    this.origcode = this.prefix + 'original';
+    this.buildcode = this.prefix + '.';
+    this.valuecode = this.prefix + 'v';
+}
+
+if (module)
+    module.exports = Resurrect;
+
+/**
+ * Portable access to the global object (window, global).
+ * Uses indirect eval.
+ * @constant
+ */
+Resurrect.GLOBAL = (0, eval)('this');
+
+/**
+ * Escape special regular expression characters in a string.
+ * @param {string} string
+ * @returns {string} The string escaped for exact matches.
+ * @see http://stackoverflow.com/a/6969486
+ */
+Resurrect.escapeRegExp = function (string) {
+    return string.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&");
+};
+
+/* Helper Objects */
+
+/**
+ * @param {string} [message]
+ * @constructor
+ */
+Resurrect.prototype.Error = function ResurrectError(message) {
+    this.message = message || '';
+    this.stack = new Error().stack;
+};
+Resurrect.prototype.Error.prototype = Object.create(Error.prototype);
+Resurrect.prototype.Error.prototype.name = 'ResurrectError';
+
+/**
+ * Resolves prototypes through the properties on an object and
+ * constructor names.
+ * @param {Object} scope
+ * @constructor
+ */
+Resurrect.NamespaceResolver = function(scope) {
+    this.scope = scope;
+};
+
+/**
+ * Gets the prototype of the given property name from an object. If
+ * not found, it throws an error.
+ * @param {string} name
+ * @returns {Object}
+ * @method
+ */
+Resurrect.NamespaceResolver.prototype.getPrototype = function(name) {
+    var constructor = this.scope[name];
+    if (constructor) {
+        return constructor.prototype;
+    } else {
+        throw new Resurrect.prototype.Error('Unknown constructor: ' + name);
+    }
+};
+
+/**
+ * Get the prototype name for an object, to be fetched later with getPrototype.
+ * @param {Object} object
+ * @returns {?string} Null if the constructor is Object.
+ * @method
+ */
+Resurrect.NamespaceResolver.prototype.getName = function(object) {
+    var constructor = object.constructor.name;
+    if (constructor == null) { // IE
+        var funcPattern = /^\s*function\s*([A-Za-z0-9_$]*)/;
+        constructor = funcPattern.exec(object.constructor)[1];
+    }
+
+    if (constructor === '') {
+        var msg = "Can't serialize objects with anonymous constructors.";
+        throw new Resurrect.prototype.Error(msg);
+    } else if (constructor === 'Object' || constructor === 'Array') {
+        return null;
+    } else {
+        return constructor;
+    }
+};
+
+/* Set the default resolver searches the global object. */
+Resurrect.prototype.resolver =
+    new Resurrect.NamespaceResolver(Resurrect.GLOBAL);
+
+/**
+ * Create a DOM node from HTML source; behaves like a constructor.
+ * @param {string} html
+ * @constructor
+ */
+Resurrect.Node = function(html) {
+    var div = document.createElement('div');
+    div.innerHTML = html;
+    return div.firstChild;
+};
+
+/* Type Tests */
+
+/**
+ * @param {string} type
+ * @returns {Function} A function that tests for type.
+ */
+Resurrect.is = function(type) {
+    var string = '[object ' + type + ']';
+    return function(object) {
+        return Object.prototype.toString.call(object) === string;
+    };
+};
+
+Resurrect.isArray = Resurrect.is('Array');
+Resurrect.isString = Resurrect.is('String');
+Resurrect.isBoolean = Resurrect.is('Boolean');
+Resurrect.isNumber = Resurrect.is('Number');
+Resurrect.isFunction = Resurrect.is('Function');
+Resurrect.isDate = Resurrect.is('Date');
+Resurrect.isRegExp = Resurrect.is('RegExp');
+Resurrect.isObject = Resurrect.is('Object');
+
+Resurrect.isAtom = function(object) {
+    return !Resurrect.isObject(object) && !Resurrect.isArray(object);
+};
+
+/**
+ * @param {*} object
+ * @returns {boolean} True if object is a primitive or a primitive wrapper.
+ */
+Resurrect.isPrimitive = function(object) {
+    return object == null ||
+        Resurrect.isNumber(object) ||
+        Resurrect.isString(object) ||
+        Resurrect.isBoolean(object);
+};
+
+/* Methods */
+
+/**
+ * Create a reference (encoding) to an object.
+ * @param {(Object|undefined)} object
+ * @returns {Object}
+ * @method
+ */
+Resurrect.prototype.ref = function(object) {
+    var ref = {};
+    if (object === undefined) {
+        ref[this.prefix] = -1;
+    } else {
+        ref[this.prefix] = object[this.refcode];
+    }
+    return ref;
+};
+
+/**
+ * Lookup an object in the table by reference object.
+ * @param {Object} ref
+ * @returns {(Object|undefined)}
+ * @method
+ */
+Resurrect.prototype.deref = function(ref) {
+    return this.table[ref[this.prefix]];
+};
+
+/**
+ * Put a temporary identifier on an object and store it in the table.
+ * @param {Object} object
+ * @returns {number} The unique identifier number.
+ * @method
+ */
+Resurrect.prototype.tag = function(object) {
+    if (this.revive) {
+        var constructor = this.resolver.getName(object);
+        if (constructor) {
+            var proto = Object.getPrototypeOf(object);
+            if (this.resolver.getPrototype(constructor) !== proto) {
+                throw new this.Error('Constructor mismatch!');
+            } else {
+                object[this.prefix] = constructor;
+            }
+        }
+    }
+    object[this.refcode] = this.table.length;
+    this.table.push(object);
+    return object[this.refcode];
+};
+
+/**
+ * Create a builder object (encoding) for serialization.
+ * @param {string} name The name of the constructor.
+ * @param value The value to pass to the constructor.
+ * @returns {Object}
+ * @method
+ */
+Resurrect.prototype.builder = function(name, value) {
+    var builder = {};
+    builder[this.buildcode] = name;
+    builder[this.valuecode] = value;
+    return builder;
+};
+
+/**
+ * Build a value from a deserialized builder.
+ * @param {Object} ref
+ * @returns {Object}
+ * @method
+ * @see http://stackoverflow.com/a/14378462
+ * @see http://nullprogram.com/blog/2013/03/24/
+ */
+Resurrect.prototype.build = function(ref) {
+    var type = ref[this.buildcode].split(/\./).reduce(function(object, name) {
+        return object[name];
+    }, Resurrect.GLOBAL);
+    /* Brilliant hack by kybernetikos: */
+    var args = [null].concat(ref[this.valuecode]);
+    var factory = type.bind.apply(type, args);
+    var result = new factory();
+    if (Resurrect.isPrimitive(result)) {
+        return result.valueOf(); // unwrap
+    } else {
+        return result;
+    }
+};
+
+/**
+ * Dereference or build an object or value from an encoding.
+ * @param {Object} ref
+ * @returns {(Object|undefined)}
+ * @method
+ */
+Resurrect.prototype.decode = function(ref) {
+    if (this.prefix in ref) {
+        return this.deref(ref);
+    } else if (this.buildcode in ref) {
+        return this.build(ref);
+    } else {
+        throw new this.Error('Unknown encoding.');
+    }
+};
+
+/**
+ * @param {Object} object
+ * @returns {boolean} True if the provided object is tagged for serialization.
+ * @method
+ */
+Resurrect.prototype.isTagged = function(object) {
+    return (this.refcode in object) && (object[this.refcode] != null);
+};
+
+/**
+ * Visit root and all its ancestors, visiting atoms with f.
+ * @param {*} root
+ * @param {Function} f
+ * @param {Function} replacer
+ * @returns {*} A fresh copy of root to be serialized.
+ * @method
+ */
+Resurrect.prototype.visit = function(root, f, replacer) {
+    if (Resurrect.isAtom(root)) {
+        return f(root);
+    } else if (!this.isTagged(root)) {
+        var copy = null;
+        if (Resurrect.isArray(root)) {
+            copy = [];
+            root[this.refcode] = this.tag(copy);
+            for (var i = 0; i < root.length; i++) {
+                copy.push(this.visit(root[i], f, replacer));
+            }
+        } else { /* Object */
+            copy = Object.create(Object.getPrototypeOf(root));
+            root[this.refcode] = this.tag(copy);
+            for (var key in root) {
+                var value = root[key];
+                if (root.hasOwnProperty(key)) {
+                    if (replacer && value !== undefined) {
+                        // Call replacer like JSON.stringify's replacer
+                        value = replacer.call(root, key, root[key]);
+                        if (value === undefined) {
+                            continue; // Omit from result
+                        }
+                    }
+                    copy[key] = this.visit(value, f, replacer);
+                }
+            }
+        }
+        copy[this.origcode] = root;
+        return this.ref(copy);
+    } else {
+        return this.ref(root);
+    }
+};
+
+/**
+ * Manage special atom values, possibly returning an encoding.
+ * @param {*} atom
+ * @returns {*}
+ * @method
+ */
+Resurrect.prototype.handleAtom = function(atom) {
+    var Node = Resurrect.GLOBAL.Node || function() {};
+    if (Resurrect.isFunction(atom)) {
+        throw new this.Error("Can't serialize functions.");
+    } else if (atom instanceof Node) {
+        var xmls = new XMLSerializer();
+        return this.builder('Resurrect.Node', [xmls.serializeToString(atom)]);
+    } else if (Resurrect.isDate(atom)) {
+        return this.builder('Date', [atom.toISOString()]);
+    } else if (Resurrect.isRegExp(atom)) {
+        var args = atom.toString().match(/\/(.+)\/([gimy]*)/).slice(1);
+        return this.builder('RegExp', args);
+    } else if (atom === undefined) {
+        return this.ref(undefined);
+    } else if (Resurrect.isNumber(atom) && (isNaN(atom) || !isFinite(atom))) {
+        return this.builder('Number', [atom.toString()]);
+    } else {
+        return atom;
+    }
+};
+
+/**
+ * Hides intrusive keys from a user-supplied replacer.
+ * @param {Function} replacer function of two arguments (key, value)
+ * @returns {Function} A function that skips the replacer for intrusive keys.
+ * @method
+ */
+Resurrect.prototype.replacerWrapper = function(replacer) {
+    var skip = new RegExp('^' + Resurrect.escapeRegExp(this.prefix));
+    return function(k, v) {
+        if (skip.test(k)) {
+            return v;
+        } else {
+            return replacer(k, v);
+        }
+    };
+};
+
+/**
+ * Serialize an arbitrary JavaScript object, carefully preserving it.
+ * @param {*} object
+ * @param {(Function|Array)} replacer
+ * @param {string} space
+ * @method
+ */
+Resurrect.prototype.stringify = function(object, replacer, space) {
+    if (Resurrect.isFunction(replacer)) {
+        replacer = this.replacerWrapper(replacer);
+    } else if (Resurrect.isArray(replacer)) {
+        var acceptKeys = replacer;
+        replacer = function(k, v) {
+            return acceptKeys.indexOf(k) >= 0 ? v : undefined;
+        };
+    }
+    if (Resurrect.isAtom(object)) {
+        return JSON.stringify(this.handleAtom(object), replacer, space);
+    } else {
+        this.table = [];
+        this.visit(object, this.handleAtom.bind(this), replacer);
+        for (var i = 0; i < this.table.length; i++) {
+            if (this.cleanup) {
+                delete this.table[i][this.origcode][this.refcode];
+            } else {
+                this.table[i][this.origcode][this.refcode] = null;
+            }
+            delete this.table[i][this.refcode];
+            delete this.table[i][this.origcode];
+        }
+        var table = this.table;
+        this.table = null;
+        return JSON.stringify(table, null, space);
+    }
+};
+
+/**
+ * Restore the __proto__ of the given object to the proper value.
+ * @param {Object} object
+ * @returns {Object} Its argument, or a copy, with the prototype restored.
+ * @method
+ */
+Resurrect.prototype.fixPrototype = function(object) {
+    if (this.prefix in object) {
+        var name = object[this.prefix];
+        var prototype = this.resolver.getPrototype(name);
+        if ('__proto__' in object) {
+            object.__proto__ = prototype;
+            if (this.cleanup) {
+                delete object[this.prefix];
+            }
+            return object;
+        } else { // IE
+            var copy = Object.create(prototype);
+            for (var key in object) {
+                if (object.hasOwnProperty(key) && key !== this.prefix) {
+                    copy[key] = object[key];
+                }
+            }
+            return copy;
+        }
+    } else {
+        return object;
+    }
+};
+
+/**
+ * Deserialize an encoded object, restoring circularity and behavior.
+ * @param {string} string
+ * @returns {*} The decoded object or value.
+ * @method
+ */
+Resurrect.prototype.resurrect = function(string) {
+    var result = null;
+    var data = JSON.parse(string);
+    if (Resurrect.isArray(data)) {
+        this.table = data;
+        /* Restore __proto__. */
+        if (this.revive) {
+            for (var i = 0; i < this.table.length; i++) {
+                this.table[i] = this.fixPrototype(this.table[i]);
+            }
+        }
+        /* Re-establish object references and construct atoms. */
+        for (i = 0; i < this.table.length; i++) {
+            var object = this.table[i];
+            for (var key in object) {
+                if (object.hasOwnProperty(key)) {
+                    if (!(Resurrect.isAtom(object[key]))) {
+                        object[key] = this.decode(object[key]);
+                    }
+                }
+            }
+        }
+        result = this.table[0];
+    } else if (Resurrect.isObject(data)) {
+        this.table = [];
+        result = this.decode(data);
+    } else {
+        result = data;
+    }
+    this.table = null;
+    return result;
+};

test/browser/refs/svg/svg-0.json

@@ -0,0 +1,889 @@
+[
+  {
+    "bodies": {
+      "#": 1
+    },
+    "bounds": {
+      "#": 86
+    },
+    "composites": {
+      "#": 89
+    },
+    "constraints": {
+      "#": 90
+    },
+    "gravity": {
+      "#": 94
+    },
+    "id": 0,
+    "isModified": true,
+    "label": "World",
+    "parent": "",
+    "type": "composite"
+  },
+  [
+    {
+      "#": 2
+    },
+    {
+      "#": 23
+    },
+    {
+      "#": 44
+    },
+    {
+      "#": 65
+    }
+  ],
+  {
+    "angle": 0,
+    "anglePrev": 0,
+    "angularSpeed": 0,
+    "angularVelocity": 0,
+    "area": 40930.25,
+    "axes": {
+      "#": 3
+    },
+    "bounds": {
+      "#": 6
+    },
+    "collisionFilter": {
+      "#": 9
+    },
+    "constraintImpulse": {
+      "#": 10
+    },
+    "density": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "force": {
+      "#": 11
+    },
+    "friction": 1,
+    "frictionAir": 0.01,
+    "frictionStatic": 0.5,
+    "id": 0,
+    "inertia": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "inverseInertia": 0,
+    "inverseMass": 0,
+    "isSleeping": false,
+    "isStatic": true,
+    "label": "Rectangle Body",
+    "mass": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "motion": 0,
+    "parent": null,
+    "position": {
+      "#": 12
+    },
+    "positionImpulse": {
+      "#": 13
+    },
+    "positionPrev": {
+      "#": 14
+    },
+    "render": {
+      "#": 15
+    },
+    "restitution": 0,
+    "sleepCounter": 0,
+    "sleepThreshold": 60,
+    "slop": 0.05,
+    "speed": 0,
+    "timeScale": 1,
+    "torque": 0,
+    "totalContacts": 0,
+    "type": "body",
+    "velocity": {
+      "#": 17
+    },
+    "vertices": {
+      "#": 18
+    }
+  },
+  [
+    {
+      "#": 4
+    },
+    {
+      "#": 5
+    }
+  ],
+  {
+    "x": 0,
+    "y": 1
+  },
+  {
+    "x": -1,
+    "y": 0
+  },
+  {
+    "max": {
+      "#": 7
+    },
+    "min": {
+      "#": 8
+    }
+  },
+  {
+    "x": 805.25,
+    "y": 20.25
+  },
+  {
+    "x": -5.25,
+    "y": -30.25
+  },
+  {
+    "category": 1,
+    "group": 0,
+    "mask": 4294967295
+  },
+  {
+    "angle": 0,
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 400,
+    "y": -5
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 400,
+    "y": -5
+  },
+  {
+    "fillStyle": "#eeeeee",
+    "lineWidth": 1.5,
+    "sprite": {
+      "#": 16
+    },
+    "strokeStyle": "#bbbbbb",
+    "visible": true
+  },
+  {
+    "xScale": 1,
+    "yScale": 1
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  [
+    {
+      "#": 19
+    },
+    {
+      "#": 20
+    },
+    {
+      "#": 21
+    },
+    {
+      "#": 22
+    }
+  ],
+  {
+    "body": null,
+    "index": 0,
+    "isInternal": false,
+    "x": -5.25,
+    "y": -30.25
+  },
+  {
+    "body": null,
+    "index": 1,
+    "isInternal": false,
+    "x": 805.25,
+    "y": -30.25
+  },
+  {
+    "body": null,
+    "index": 2,
+    "isInternal": false,
+    "x": 805.25,
+    "y": 20.25
+  },
+  {
+    "body": null,
+    "index": 3,
+    "isInternal": false,
+    "x": -5.25,
+    "y": 20.25
+  },
+  {
+    "angle": 0,
+    "anglePrev": 0,
+    "angularSpeed": 0,
+    "angularVelocity": 0,
+    "area": 40930.25,
+    "axes": {
+      "#": 24
+    },
+    "bounds": {
+      "#": 27
+    },
+    "collisionFilter": {
+      "#": 30
+    },
+    "constraintImpulse": {
+      "#": 31
+    },
+    "density": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "force": {
+      "#": 32
+    },
+    "friction": 1,
+    "frictionAir": 0.01,
+    "frictionStatic": 0.5,
+    "id": 1,
+    "inertia": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "inverseInertia": 0,
+    "inverseMass": 0,
+    "isSleeping": false,
+    "isStatic": true,
+    "label": "Rectangle Body",
+    "mass": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "motion": 0,
+    "parent": null,
+    "position": {
+      "#": 33
+    },
+    "positionImpulse": {
+      "#": 34
+    },
+    "positionPrev": {
+      "#": 35
+    },
+    "render": {
+      "#": 36
+    },
+    "restitution": 0,
+    "sleepCounter": 0,
+    "sleepThreshold": 60,
+    "slop": 0.05,
+    "speed": 0,
+    "timeScale": 1,
+    "torque": 0,
+    "totalContacts": 0,
+    "type": "body",
+    "velocity": {
+      "#": 38
+    },
+    "vertices": {
+      "#": 39
+    }
+  },
+  [
+    {
+      "#": 25
+    },
+    {
+      "#": 26
+    }
+  ],
+  {
+    "x": 0,
+    "y": 1
+  },
+  {
+    "x": -1,
+    "y": 0
+  },
+  {
+    "max": {
+      "#": 28
+    },
+    "min": {
+      "#": 29
+    }
+  },
+  {
+    "x": 805.25,
+    "y": 630.25
+  },
+  {
+    "x": -5.25,
+    "y": 579.75
+  },
+  {
+    "category": 1,
+    "group": 0,
+    "mask": 4294967295
+  },
+  {
+    "angle": 0,
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 400,
+    "y": 605
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 400,
+    "y": 605
+  },
+  {
+    "fillStyle": "#eeeeee",
+    "lineWidth": 1.5,
+    "sprite": {
+      "#": 37
+    },
+    "strokeStyle": "#bbbbbb",
+    "visible": true
+  },
+  {
+    "xScale": 1,
+    "yScale": 1
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  [
+    {
+      "#": 40
+    },
+    {
+      "#": 41
+    },
+    {
+      "#": 42
+    },
+    {
+      "#": 43
+    }
+  ],
+  {
+    "body": null,
+    "index": 0,
+    "isInternal": false,
+    "x": -5.25,
+    "y": 579.75
+  },
+  {
+    "body": null,
+    "index": 1,
+    "isInternal": false,
+    "x": 805.25,
+    "y": 579.75
+  },
+  {
+    "body": null,
+    "index": 2,
+    "isInternal": false,
+    "x": 805.25,
+    "y": 630.25
+  },
+  {
+    "body": null,
+    "index": 3,
+    "isInternal": false,
+    "x": -5.25,
+    "y": 630.25
+  },
+  {
+    "angle": 0,
+    "anglePrev": 0,
+    "angularSpeed": 0,
+    "angularVelocity": 0,
+    "area": 30830.25,
+    "axes": {
+      "#": 45
+    },
+    "bounds": {
+      "#": 48
+    },
+    "collisionFilter": {
+      "#": 51
+    },
+    "constraintImpulse": {
+      "#": 52
+    },
+    "density": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "force": {
+      "#": 53
+    },
+    "friction": 1,
+    "frictionAir": 0.01,
+    "frictionStatic": 0.5,
+    "id": 2,
+    "inertia": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "inverseInertia": 0,
+    "inverseMass": 0,
+    "isSleeping": false,
+    "isStatic": true,
+    "label": "Rectangle Body",
+    "mass": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "motion": 0,
+    "parent": null,
+    "position": {
+      "#": 54
+    },
+    "positionImpulse": {
+      "#": 55
+    },
+    "positionPrev": {
+      "#": 56
+    },
+    "render": {
+      "#": 57
+    },
+    "restitution": 0,
+    "sleepCounter": 0,
+    "sleepThreshold": 60,
+    "slop": 0.05,
+    "speed": 0,
+    "timeScale": 1,
+    "torque": 0,
+    "totalContacts": 0,
+    "type": "body",
+    "velocity": {
+      "#": 59
+    },
+    "vertices": {
+      "#": 60
+    }
+  },
+  [
+    {
+      "#": 46
+    },
+    {
+      "#": 47
+    }
+  ],
+  {
+    "x": 0,
+    "y": 1
+  },
+  {
+    "x": -1,
+    "y": 0
+  },
+  {
+    "max": {
+      "#": 49
+    },
+    "min": {
+      "#": 50
+    }
+  },
+  {
+    "x": 830.25,
+    "y": 605.25
+  },
+  {
+    "x": 779.75,
+    "y": -5.25
+  },
+  {
+    "category": 1,
+    "group": 0,
+    "mask": 4294967295
+  },
+  {
+    "angle": 0,
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 805,
+    "y": 300
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 805,
+    "y": 300
+  },
+  {
+    "fillStyle": "#eeeeee",
+    "lineWidth": 1.5,
+    "sprite": {
+      "#": 58
+    },
+    "strokeStyle": "#bbbbbb",
+    "visible": true
+  },
+  {
+    "xScale": 1,
+    "yScale": 1
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  [
+    {
+      "#": 61
+    },
+    {
+      "#": 62
+    },
+    {
+      "#": 63
+    },
+    {
+      "#": 64
+    }
+  ],
+  {
+    "body": null,
+    "index": 0,
+    "isInternal": false,
+    "x": 779.75,
+    "y": -5.25
+  },
+  {
+    "body": null,
+    "index": 1,
+    "isInternal": false,
+    "x": 830.25,
+    "y": -5.25
+  },
+  {
+    "body": null,
+    "index": 2,
+    "isInternal": false,
+    "x": 830.25,
+    "y": 605.25
+  },
+  {
+    "body": null,
+    "index": 3,
+    "isInternal": false,
+    "x": 779.75,
+    "y": 605.25
+  },
+  {
+    "angle": 0,
+    "anglePrev": 0,
+    "angularSpeed": 0,
+    "angularVelocity": 0,
+    "area": 30830.25,
+    "axes": {
+      "#": 66
+    },
+    "bounds": {
+      "#": 69
+    },
+    "collisionFilter": {
+      "#": 72
+    },
+    "constraintImpulse": {
+      "#": 73
+    },
+    "density": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "force": {
+      "#": 74
+    },
+    "friction": 1,
+    "frictionAir": 0.01,
+    "frictionStatic": 0.5,
+    "id": 3,
+    "inertia": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "inverseInertia": 0,
+    "inverseMass": 0,
+    "isSleeping": false,
+    "isStatic": true,
+    "label": "Rectangle Body",
+    "mass": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "motion": 0,
+    "parent": null,
+    "position": {
+      "#": 75
+    },
+    "positionImpulse": {
+      "#": 76
+    },
+    "positionPrev": {
+      "#": 77
+    },
+    "render": {
+      "#": 78
+    },
+    "restitution": 0,
+    "sleepCounter": 0,
+    "sleepThreshold": 60,
+    "slop": 0.05,
+    "speed": 0,
+    "timeScale": 1,
+    "torque": 0,
+    "totalContacts": 0,
+    "type": "body",
+    "velocity": {
+      "#": 80
+    },
+    "vertices": {
+      "#": 81
+    }
+  },
+  [
+    {
+      "#": 67
+    },
+    {
+      "#": 68
+    }
+  ],
+  {
+    "x": 0,
+    "y": 1
+  },
+  {
+    "x": -1,
+    "y": 0
+  },
+  {
+    "max": {
+      "#": 70
+    },
+    "min": {
+      "#": 71
+    }
+  },
+  {
+    "x": 20.25,
+    "y": 605.25
+  },
+  {
+    "x": -30.25,
+    "y": -5.25
+  },
+  {
+    "category": 1,
+    "group": 0,
+    "mask": 4294967295
+  },
+  {
+    "angle": 0,
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": -5,
+    "y": 300
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": -5,
+    "y": 300
+  },
+  {
+    "fillStyle": "#eeeeee",
+    "lineWidth": 1.5,
+    "sprite": {
+      "#": 79
+    },
+    "strokeStyle": "#bbbbbb",
+    "visible": true
+  },
+  {
+    "xScale": 1,
+    "yScale": 1
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  [
+    {
+      "#": 82
+    },
+    {
+      "#": 83
+    },
+    {
+      "#": 84
+    },
+    {
+      "#": 85
+    }
+  ],
+  {
+    "body": null,
+    "index": 0,
+    "isInternal": false,
+    "x": -30.25,
+    "y": -5.25
+  },
+  {
+    "body": null,
+    "index": 1,
+    "isInternal": false,
+    "x": 20.25,
+    "y": -5.25
+  },
+  {
+    "body": null,
+    "index": 2,
+    "isInternal": false,
+    "x": 20.25,
+    "y": 605.25
+  },
+  {
+    "body": null,
+    "index": 3,
+    "isInternal": false,
+    "x": -30.25,
+    "y": 605.25
+  },
+  {
+    "max": {
+      "#": 87
+    },
+    "min": {
+      "#": 88
+    }
+  },
+  {
+    "x": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "y": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    }
+  },
+  {
+    "x": {
+      "#.": "Number",
+      "#v": [
+        "-Infinity"
+      ]
+    },
+    "y": {
+      "#.": "Number",
+      "#v": [
+        "-Infinity"
+      ]
+    }
+  },
+  [],
+  [
+    {
+      "#": 91
+    }
+  ],
+  {
+    "angularStiffness": 1,
+    "bodyB": "",
+    "id": 1,
+    "label": "Mouse Constraint",
+    "length": 0.01,
+    "pointA": {
+      "#": 92
+    },
+    "pointB": "",
+    "render": {
+      "#": 93
+    },
+    "stiffness": 0.1,
+    "type": "constraint"
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "lineWidth": 3,
+    "strokeStyle": "#90EE90",
+    "visible": true
+  },
+  {
+    "x": 0,
+    "y": 1
+  }
+]

test/browser/refs/svg/svg-10.json

@@ -0,0 +1,929 @@
+[
+  {
+    "bodies": {
+      "#": 1
+    },
+    "bounds": {
+      "#": 90
+    },
+    "composites": {
+      "#": 93
+    },
+    "constraints": {
+      "#": 94
+    },
+    "gravity": {
+      "#": 98
+    },
+    "id": 0,
+    "isModified": false,
+    "label": "World",
+    "parent": "",
+    "type": "composite"
+  },
+  [
+    {
+      "#": 2
+    },
+    {
+      "#": 24
+    },
+    {
+      "#": 46
+    },
+    {
+      "#": 68
+    }
+  ],
+  {
+    "angle": 0,
+    "anglePrev": 0,
+    "angularSpeed": 0,
+    "angularVelocity": 0,
+    "area": 40930.25,
+    "axes": {
+      "#": 3
+    },
+    "bounds": {
+      "#": 6
+    },
+    "collisionFilter": {
+      "#": 9
+    },
+    "constraintImpulse": {
+      "#": 10
+    },
+    "density": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "force": {
+      "#": 11
+    },
+    "friction": 1,
+    "frictionAir": 0.01,
+    "frictionStatic": 0.5,
+    "id": 0,
+    "inertia": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "inverseInertia": 0,
+    "inverseMass": 0,
+    "isSleeping": false,
+    "isStatic": true,
+    "label": "Rectangle Body",
+    "mass": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "motion": 0,
+    "parent": null,
+    "position": {
+      "#": 12
+    },
+    "positionImpulse": {
+      "#": 13
+    },
+    "positionPrev": {
+      "#": 14
+    },
+    "region": {
+      "#": 15
+    },
+    "render": {
+      "#": 16
+    },
+    "restitution": 0,
+    "sleepCounter": 0,
+    "sleepThreshold": 60,
+    "slop": 0.05,
+    "speed": 0,
+    "timeScale": 1,
+    "torque": 0,
+    "totalContacts": 0,
+    "type": "body",
+    "velocity": {
+      "#": 18
+    },
+    "vertices": {
+      "#": 19
+    }
+  },
+  [
+    {
+      "#": 4
+    },
+    {
+      "#": 5
+    }
+  ],
+  {
+    "x": 0,
+    "y": 1
+  },
+  {
+    "x": -1,
+    "y": 0
+  },
+  {
+    "max": {
+      "#": 7
+    },
+    "min": {
+      "#": 8
+    }
+  },
+  {
+    "x": 805.25,
+    "y": 20.25
+  },
+  {
+    "x": -5.25,
+    "y": -30.25
+  },
+  {
+    "category": 1,
+    "group": 0,
+    "mask": 4294967295
+  },
+  {
+    "angle": 0,
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 400,
+    "y": -5
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 400,
+    "y": -5
+  },
+  {
+    "endCol": 16,
+    "endRow": 0,
+    "id": "-1,16,-1,0",
+    "startCol": -1,
+    "startRow": -1
+  },
+  {
+    "fillStyle": "#eeeeee",
+    "lineWidth": 1.5,
+    "sprite": {
+      "#": 17
+    },
+    "strokeStyle": "#bbbbbb",
+    "visible": true
+  },
+  {
+    "xScale": 1,
+    "yScale": 1
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  [
+    {
+      "#": 20
+    },
+    {
+      "#": 21
+    },
+    {
+      "#": 22
+    },
+    {
+      "#": 23
+    }
+  ],
+  {
+    "body": null,
+    "index": 0,
+    "isInternal": false,
+    "x": -5.25,
+    "y": -30.25
+  },
+  {
+    "body": null,
+    "index": 1,
+    "isInternal": false,
+    "x": 805.25,
+    "y": -30.25
+  },
+  {
+    "body": null,
+    "index": 2,
+    "isInternal": false,
+    "x": 805.25,
+    "y": 20.25
+  },
+  {
+    "body": null,
+    "index": 3,
+    "isInternal": false,
+    "x": -5.25,
+    "y": 20.25
+  },
+  {
+    "angle": 0,
+    "anglePrev": 0,
+    "angularSpeed": 0,
+    "angularVelocity": 0,
+    "area": 40930.25,
+    "axes": {
+      "#": 25
+    },
+    "bounds": {
+      "#": 28
+    },
+    "collisionFilter": {
+      "#": 31
+    },
+    "constraintImpulse": {
+      "#": 32
+    },
+    "density": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "force": {
+      "#": 33
+    },
+    "friction": 1,
+    "frictionAir": 0.01,
+    "frictionStatic": 0.5,
+    "id": 1,
+    "inertia": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "inverseInertia": 0,
+    "inverseMass": 0,
+    "isSleeping": false,
+    "isStatic": true,
+    "label": "Rectangle Body",
+    "mass": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "motion": 0,
+    "parent": null,
+    "position": {
+      "#": 34
+    },
+    "positionImpulse": {
+      "#": 35
+    },
+    "positionPrev": {
+      "#": 36
+    },
+    "region": {
+      "#": 37
+    },
+    "render": {
+      "#": 38
+    },
+    "restitution": 0,
+    "sleepCounter": 0,
+    "sleepThreshold": 60,
+    "slop": 0.05,
+    "speed": 0,
+    "timeScale": 1,
+    "torque": 0,
+    "totalContacts": 0,
+    "type": "body",
+    "velocity": {
+      "#": 40
+    },
+    "vertices": {
+      "#": 41
+    }
+  },
+  [
+    {
+      "#": 26
+    },
+    {
+      "#": 27
+    }
+  ],
+  {
+    "x": 0,
+    "y": 1
+  },
+  {
+    "x": -1,
+    "y": 0
+  },
+  {
+    "max": {
+      "#": 29
+    },
+    "min": {
+      "#": 30
+    }
+  },
+  {
+    "x": 805.25,
+    "y": 630.25
+  },
+  {
+    "x": -5.25,
+    "y": 579.75
+  },
+  {
+    "category": 1,
+    "group": 0,
+    "mask": 4294967295
+  },
+  {
+    "angle": 0,
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 400,
+    "y": 605
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 400,
+    "y": 605
+  },
+  {
+    "endCol": 16,
+    "endRow": 13,
+    "id": "-1,16,12,13",
+    "startCol": -1,
+    "startRow": 12
+  },
+  {
+    "fillStyle": "#eeeeee",
+    "lineWidth": 1.5,
+    "sprite": {
+      "#": 39
+    },
+    "strokeStyle": "#bbbbbb",
+    "visible": true
+  },
+  {
+    "xScale": 1,
+    "yScale": 1
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  [
+    {
+      "#": 42
+    },
+    {
+      "#": 43
+    },
+    {
+      "#": 44
+    },
+    {
+      "#": 45
+    }
+  ],
+  {
+    "body": null,
+    "index": 0,
+    "isInternal": false,
+    "x": -5.25,
+    "y": 579.75
+  },
+  {
+    "body": null,
+    "index": 1,
+    "isInternal": false,
+    "x": 805.25,
+    "y": 579.75
+  },
+  {
+    "body": null,
+    "index": 2,
+    "isInternal": false,
+    "x": 805.25,
+    "y": 630.25
+  },
+  {
+    "body": null,
+    "index": 3,
+    "isInternal": false,
+    "x": -5.25,
+    "y": 630.25
+  },
+  {
+    "angle": 0,
+    "anglePrev": 0,
+    "angularSpeed": 0,
+    "angularVelocity": 0,
+    "area": 30830.25,
+    "axes": {
+      "#": 47
+    },
+    "bounds": {
+      "#": 50
+    },
+    "collisionFilter": {
+      "#": 53
+    },
+    "constraintImpulse": {
+      "#": 54
+    },
+    "density": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "force": {
+      "#": 55
+    },
+    "friction": 1,
+    "frictionAir": 0.01,
+    "frictionStatic": 0.5,
+    "id": 2,
+    "inertia": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "inverseInertia": 0,
+    "inverseMass": 0,
+    "isSleeping": false,
+    "isStatic": true,
+    "label": "Rectangle Body",
+    "mass": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "motion": 0,
+    "parent": null,
+    "position": {
+      "#": 56
+    },
+    "positionImpulse": {
+      "#": 57
+    },
+    "positionPrev": {
+      "#": 58
+    },
+    "region": {
+      "#": 59
+    },
+    "render": {
+      "#": 60
+    },
+    "restitution": 0,
+    "sleepCounter": 0,
+    "sleepThreshold": 60,
+    "slop": 0.05,
+    "speed": 0,
+    "timeScale": 1,
+    "torque": 0,
+    "totalContacts": 0,
+    "type": "body",
+    "velocity": {
+      "#": 62
+    },
+    "vertices": {
+      "#": 63
+    }
+  },
+  [
+    {
+      "#": 48
+    },
+    {
+      "#": 49
+    }
+  ],
+  {
+    "x": 0,
+    "y": 1
+  },
+  {
+    "x": -1,
+    "y": 0
+  },
+  {
+    "max": {
+      "#": 51
+    },
+    "min": {
+      "#": 52
+    }
+  },
+  {
+    "x": 830.25,
+    "y": 605.25
+  },
+  {
+    "x": 779.75,
+    "y": -5.25
+  },
+  {
+    "category": 1,
+    "group": 0,
+    "mask": 4294967295
+  },
+  {
+    "angle": 0,
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 805,
+    "y": 300
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 805,
+    "y": 300
+  },
+  {
+    "endCol": 17,
+    "endRow": 12,
+    "id": "16,17,-1,12",
+    "startCol": 16,
+    "startRow": -1
+  },
+  {
+    "fillStyle": "#eeeeee",
+    "lineWidth": 1.5,
+    "sprite": {
+      "#": 61
+    },
+    "strokeStyle": "#bbbbbb",
+    "visible": true
+  },
+  {
+    "xScale": 1,
+    "yScale": 1
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  [
+    {
+      "#": 64
+    },
+    {
+      "#": 65
+    },
+    {
+      "#": 66
+    },
+    {
+      "#": 67
+    }
+  ],
+  {
+    "body": null,
+    "index": 0,
+    "isInternal": false,
+    "x": 779.75,
+    "y": -5.25
+  },
+  {
+    "body": null,
+    "index": 1,
+    "isInternal": false,
+    "x": 830.25,
+    "y": -5.25
+  },
+  {
+    "body": null,
+    "index": 2,
+    "isInternal": false,
+    "x": 830.25,
+    "y": 605.25
+  },
+  {
+    "body": null,
+    "index": 3,
+    "isInternal": false,
+    "x": 779.75,
+    "y": 605.25
+  },
+  {
+    "angle": 0,
+    "anglePrev": 0,
+    "angularSpeed": 0,
+    "angularVelocity": 0,
+    "area": 30830.25,
+    "axes": {
+      "#": 69
+    },
+    "bounds": {
+      "#": 72
+    },
+    "collisionFilter": {
+      "#": 75
+    },
+    "constraintImpulse": {
+      "#": 76
+    },
+    "density": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "force": {
+      "#": 77
+    },
+    "friction": 1,
+    "frictionAir": 0.01,
+    "frictionStatic": 0.5,
+    "id": 3,
+    "inertia": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "inverseInertia": 0,
+    "inverseMass": 0,
+    "isSleeping": false,
+    "isStatic": true,
+    "label": "Rectangle Body",
+    "mass": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "motion": 0,
+    "parent": null,
+    "position": {
+      "#": 78
+    },
+    "positionImpulse": {
+      "#": 79
+    },
+    "positionPrev": {
+      "#": 80
+    },
+    "region": {
+      "#": 81
+    },
+    "render": {
+      "#": 82
+    },
+    "restitution": 0,
+    "sleepCounter": 0,
+    "sleepThreshold": 60,
+    "slop": 0.05,
+    "speed": 0,
+    "timeScale": 1,
+    "torque": 0,
+    "totalContacts": 0,
+    "type": "body",
+    "velocity": {
+      "#": 84
+    },
+    "vertices": {
+      "#": 85
+    }
+  },
+  [
+    {
+      "#": 70
+    },
+    {
+      "#": 71
+    }
+  ],
+  {
+    "x": 0,
+    "y": 1
+  },
+  {
+    "x": -1,
+    "y": 0
+  },
+  {
+    "max": {
+      "#": 73
+    },
+    "min": {
+      "#": 74
+    }
+  },
+  {
+    "x": 20.25,
+    "y": 605.25
+  },
+  {
+    "x": -30.25,
+    "y": -5.25
+  },
+  {
+    "category": 1,
+    "group": 0,
+    "mask": 4294967295
+  },
+  {
+    "angle": 0,
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": -5,
+    "y": 300
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "x": -5,
+    "y": 300
+  },
+  {
+    "endCol": 0,
+    "endRow": 12,
+    "id": "-1,0,-1,12",
+    "startCol": -1,
+    "startRow": -1
+  },
+  {
+    "fillStyle": "#eeeeee",
+    "lineWidth": 1.5,
+    "sprite": {
+      "#": 83
+    },
+    "strokeStyle": "#bbbbbb",
+    "visible": true
+  },
+  {
+    "xScale": 1,
+    "yScale": 1
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  [
+    {
+      "#": 86
+    },
+    {
+      "#": 87
+    },
+    {
+      "#": 88
+    },
+    {
+      "#": 89
+    }
+  ],
+  {
+    "body": null,
+    "index": 0,
+    "isInternal": false,
+    "x": -30.25,
+    "y": -5.25
+  },
+  {
+    "body": null,
+    "index": 1,
+    "isInternal": false,
+    "x": 20.25,
+    "y": -5.25
+  },
+  {
+    "body": null,
+    "index": 2,
+    "isInternal": false,
+    "x": 20.25,
+    "y": 605.25
+  },
+  {
+    "body": null,
+    "index": 3,
+    "isInternal": false,
+    "x": -30.25,
+    "y": 605.25
+  },
+  {
+    "max": {
+      "#": 91
+    },
+    "min": {
+      "#": 92
+    }
+  },
+  {
+    "x": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "y": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    }
+  },
+  {
+    "x": {
+      "#.": "Number",
+      "#v": [
+        "-Infinity"
+      ]
+    },
+    "y": {
+      "#.": "Number",
+      "#v": [
+        "-Infinity"
+      ]
+    }
+  },
+  [],
+  [
+    {
+      "#": 95
+    }
+  ],
+  {
+    "angularStiffness": 1,
+    "bodyB": "",
+    "id": 1,
+    "label": "Mouse Constraint",
+    "length": 0.01,
+    "pointA": {
+      "#": 96
+    },
+    "pointB": "",
+    "render": {
+      "#": 97
+    },
+    "stiffness": 0.1,
+    "type": "constraint"
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "lineWidth": 3,
+    "strokeStyle": "#90EE90",
+    "visible": true
+  },
+  {
+    "x": 0,
+    "y": 1
+  }
+]

test/browser/refs/terrain/terrain-0.json

@@ -0,0 +1,96 @@
+[
+  {
+    "bodies": {
+      "#": 1
+    },
+    "bounds": {
+      "#": 2
+    },
+    "composites": {
+      "#": 5
+    },
+    "constraints": {
+      "#": 6
+    },
+    "gravity": {
+      "#": 10
+    },
+    "id": 0,
+    "isModified": true,
+    "label": "World",
+    "parent": "",
+    "type": "composite"
+  },
+  [],
+  {
+    "max": {
+      "#": 3
+    },
+    "min": {
+      "#": 4
+    }
+  },
+  {
+    "x": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "y": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    }
+  },
+  {
+    "x": {
+      "#.": "Number",
+      "#v": [
+        "-Infinity"
+      ]
+    },
+    "y": {
+      "#.": "Number",
+      "#v": [
+        "-Infinity"
+      ]
+    }
+  },
+  [],
+  [
+    {
+      "#": 7
+    }
+  ],
+  {
+    "angularStiffness": 1,
+    "bodyB": "",
+    "id": 1,
+    "label": "Mouse Constraint",
+    "length": 0.01,
+    "pointA": {
+      "#": 8
+    },
+    "pointB": "",
+    "render": {
+      "#": 9
+    },
+    "stiffness": 0.1,
+    "type": "constraint"
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "lineWidth": 3,
+    "strokeStyle": "#90EE90",
+    "visible": true
+  },
+  {
+    "x": 0,
+    "y": 1
+  }
+]

test/browser/refs/terrain/terrain-10.json

@@ -0,0 +1,96 @@
+[
+  {
+    "bodies": {
+      "#": 1
+    },
+    "bounds": {
+      "#": 2
+    },
+    "composites": {
+      "#": 5
+    },
+    "constraints": {
+      "#": 6
+    },
+    "gravity": {
+      "#": 10
+    },
+    "id": 0,
+    "isModified": false,
+    "label": "World",
+    "parent": "",
+    "type": "composite"
+  },
+  [],
+  {
+    "max": {
+      "#": 3
+    },
+    "min": {
+      "#": 4
+    }
+  },
+  {
+    "x": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    },
+    "y": {
+      "#.": "Number",
+      "#v": [
+        "Infinity"
+      ]
+    }
+  },
+  {
+    "x": {
+      "#.": "Number",
+      "#v": [
+        "-Infinity"
+      ]
+    },
+    "y": {
+      "#.": "Number",
+      "#v": [
+        "-Infinity"
+      ]
+    }
+  },
+  [],
+  [
+    {
+      "#": 7
+    }
+  ],
+  {
+    "angularStiffness": 1,
+    "bodyB": "",
+    "id": 1,
+    "label": "Mouse Constraint",
+    "length": 0.01,
+    "pointA": {
+      "#": 8
+    },
+    "pointB": "",
+    "render": {
+      "#": 9
+    },
+    "stiffness": 0.1,
+    "type": "constraint"
+  },
+  {
+    "x": 0,
+    "y": 0
+  },
+  {
+    "lineWidth": 3,
+    "strokeStyle": "#90EE90",
+    "visible": true
+  },
+  {
+    "x": 0,
+    "y": 1
+  }
+]