optimised Matter.Composite

src/body/Composite.js

@@ -39,7 +39,12 @@ var Body = require('./Body');
             constraints: [], 
             composites: [],
             label: 'Composite',
-            plugin: {}
+            plugin: {},
+            cache: {
+                allBodies: null,
+                allConstraints: null,
+                allComposites: null
+            }
         }, options);
     };
 
@@ -47,6 +52,7 @@ var Body = require('./Body');
      * Sets the composite's `isModified` flag. 
      * If `updateParents` is true, all parents will be set (default: false).
      * If `updateChildren` is true, all children will be set (default: false).
+     * @private
      * @method setModified
      * @param {composite} composite
      * @param {boolean} isModified
@@ -56,6 +62,12 @@ var Body = require('./Body');
     Composite.setModified = function(composite, isModified, updateParents, updateChildren) {
         composite.isModified = isModified;
 
+        if (isModified) {
+            composite.cache.allBodies = null;
+            composite.cache.allConstraints = null;
+            composite.cache.allComposites = null;
+        }
+
         if (updateParents && composite.parent) {
             Composite.setModified(composite.parent, isModified, updateParents, updateChildren);
         }
@@ -182,7 +194,6 @@ var Body = require('./Body');
         var position = Common.indexOf(compositeA.composites, compositeB);
         if (position !== -1) {
             Composite.removeCompositeAt(compositeA, position);
-            Composite.setModified(compositeA, true, true, false);
         }
 
         if (deep) {
@@ -235,7 +246,6 @@ var Body = require('./Body');
         var position = Common.indexOf(composite.bodies, body);
         if (position !== -1) {
             Composite.removeBodyAt(composite, position);
-            Composite.setModified(composite, true, true, false);
         }
 
         if (deep) {
@@ -336,6 +346,7 @@ var Body = require('./Body');
 
         composite.constraints.length = 0;
         composite.composites.length = 0;
+
         Composite.setModified(composite, true, true, false);
 
         return composite;
@@ -348,11 +359,17 @@ var Body = require('./Body');
      * @return {body[]} All the bodies
      */
     Composite.allBodies = function(composite) {
+        if (composite.cache.allBodies) {
+            return composite.cache.allBodies;
+        }
+
         var bodies = [].concat(composite.bodies);
 
         for (var i = 0; i < composite.composites.length; i++)
             bodies = bodies.concat(Composite.allBodies(composite.composites[i]));
 
+        composite.cache.allBodies = bodies;
+
         return bodies;
     };
 
@@ -363,11 +380,17 @@ var Body = require('./Body');
      * @return {constraint[]} All the constraints
      */
     Composite.allConstraints = function(composite) {
+        if (composite.cache.allConstraints) {
+            return composite.cache.allConstraints;
+        }
+
         var constraints = [].concat(composite.constraints);
 
         for (var i = 0; i < composite.composites.length; i++)
             constraints = constraints.concat(Composite.allConstraints(composite.composites[i]));
 
+        composite.cache.allConstraints = constraints;
+
         return constraints;
     };
 
@@ -378,11 +401,17 @@ var Body = require('./Body');
      * @return {composite[]} All the composites
      */
     Composite.allComposites = function(composite) {
+        if (composite.cache.allComposites) {
+            return composite.cache.allComposites;
+        }
+
         var composites = [].concat(composite.composites);
 
         for (var i = 0; i < composite.composites.length; i++)
             composites = composites.concat(Composite.allComposites(composite.composites[i]));
 
+        composite.cache.allComposites = composites;
+
         return composites;
     };
 
@@ -449,8 +478,6 @@ var Body = require('./Body');
             objects[i].id = Common.nextId();
         }
 
-        Composite.setModified(composite, true, true, false);
-
         return composite;
     };
 
@@ -469,8 +496,6 @@ var Body = require('./Body');
             Body.translate(bodies[i], translation);
         }
 
-        Composite.setModified(composite, true, true, false);
-
         return composite;
     };
 
@@ -500,8 +525,6 @@ var Body = require('./Body');
             Body.rotate(body, rotation);
         }
 
-        Composite.setModified(composite, true, true, false);
-
         return composite;
     };
 
@@ -530,8 +553,6 @@ var Body = require('./Body');
             Body.scale(body, scaleX, scaleY);
         }
 
-        Composite.setModified(composite, true, true, false);
-
         return composite;
     };
 
@@ -631,8 +652,7 @@ var Body = require('./Body');
 
     /**
      * A flag that specifies whether the composite has been modified during the current step.
-     * Most `Matter.Composite` methods will automatically set this flag to `true` to inform the engine of changes to be handled.
-     * If you need to change it manually, you should use the `Composite.setModified` method.
+     * This is automatically managed when bodies, constraints or composites are added or removed.
      *
      * @property isModified
      * @type boolean
@@ -684,4 +704,13 @@ var Body = require('./Body');
      * @type {}
      */
 
+    /**
+     * An object used for storing cached results for performance reasons.
+     * This is used internally only and is automatically managed.
+     *
+     * @private
+     * @property cache
+     * @type {}
+     */
+
 })();