Manager has now become the Pairs data structure

src/collision/Pairs.js

@@ -0,0 +1,149 @@
+/**
+* _Internal Class_, not generally used outside of the engine's internals.
+*
+* @class Pairs
+*/
+
+var Pairs = {};
+
+(function() {
+    
+    var _pairMaxIdleLife = 1000;
+
+    /**
+     * Creates a new pairs structure
+     * @method create
+     * @param {object} options
+     * @return {pairs} A new pairs structure
+     */
+    Pairs.create = function(options) {
+        return Common.extend({ 
+            table: {},
+            list: [],
+            collisionStart: [],
+            collisionActive: [],
+            collisionEnd: []
+        }, options);
+    };
+
+    /**
+     * Description
+     * @method update
+     * @param {object} pairs
+     * @param {collision[]} collisions
+     */
+    Pairs.update = function(pairs, collisions, timestamp) {
+        var pairsList = pairs.list,
+            pairsTable = pairs.table,
+            collisionStart = pairs.collisionStart,
+            collisionEnd = pairs.collisionEnd,
+            collisionActive = pairs.collisionActive,
+            activePairIds = [],
+            collision,
+            pairId,
+            pair,
+            i;
+
+        // clear collision state arrays, but maintain old reference
+        collisionStart.length = 0;
+        collisionEnd.length = 0;
+        collisionActive.length = 0;
+
+        for (i = 0; i < collisions.length; i++) {
+            collision = collisions[i];
+
+            if (collision.collided) {
+                pairId = Pair.id(collision.bodyA, collision.bodyB);
+                activePairIds.push(pairId);
+                
+                if (pairId in pairsTable) {
+                    // pair already exists (but may or may not be active)
+                    pair = pairsTable[pairId];
+
+                    if (pair.isActive) {
+                        // pair exists and is active
+                        collisionActive.push(pair);
+                    } else {
+                        // pair exists but was inactive, so a collision has just started again
+                        collisionStart.push(pair);
+                    }
+
+                    // update the pair
+                    Pair.update(pair, collision, timestamp);
+                } else {
+                    // pair did not exist, create a new pair
+                    pair = Pair.create(collision, timestamp);
+                    pairsTable[pairId] = pair;
+
+                    // push the new pair
+                    collisionStart.push(pair);
+                    pairsList.push(pair);
+                }
+            }
+        }
+
+        // deactivate previously active pairs that are now inactive
+        for (i = 0; i < pairsList.length; i++) {
+            pair = pairsList[i];
+            if (pair.isActive && activePairIds.indexOf(pair.id) === -1) {
+                Pair.setActive(pair, false, timestamp);
+                collisionEnd.push(pair);
+            }
+        }
+    };
+    
+    /**
+     * Description
+     * @method removeOld
+     * @param {object} pairs
+     */
+    Pairs.removeOld = function(pairs, timestamp) {
+        var pairsList = pairs.list,
+            pairsTable = pairs.table,
+            indexesToRemove = [],
+            pair,
+            collision,
+            pairIndex,
+            i;
+
+        for (i = 0; i < pairsList.length; i++) {
+            pair = pairsList[i];
+            collision = pair.collision;
+            
+            // never remove sleeping pairs
+            if (collision.bodyA.isSleeping || collision.bodyB.isSleeping) {
+                pair.timeUpdated = timestamp;
+                continue;
+            }
+
+            // if pair is inactive for too long, mark it to be removed
+            if (timestamp - pair.timeUpdated > _pairMaxIdleLife) {
+                indexesToRemove.push(i);
+            }
+        }
+
+        // remove marked pairs
+        for (i = 0; i < indexesToRemove.length; i++) {
+            pairIndex = indexesToRemove[i] - i;
+            pair = pairsList[pairIndex];
+            delete pairsTable[pair.id];
+            pairsList.splice(pairIndex, 1);
+        }
+    };
+
+    /**
+     * Clears the given pairs structure
+     * @method create
+     * @param {object} options
+     * @param {pairs} pairs
+     */
+    Pairs.clear = function(pairs) {
+        pairs.table = {};
+        pairs.list.length = 0;
+        pairs.collisionStart.length = 0;
+        pairs.collisionActive.length = 0;
+        pairs.collisionEnd.length = 0;
+        return pairs;
+    };
+
+})();

src/core/Engine.js

@@ -39,13 +39,6 @@ var Engine = {};
             positionIterations: 6,
             velocityIterations: 4,
             constraintIterations: 1,
-            pairs: {
-                table: {},
-                list: [],
-                collisionStart: [],
-                collisionActive: [],
-                collisionEnd: []
-            },
             enableSleeping: false,
             timeScale: 1,
             input: {},
@@ -68,6 +61,7 @@ var Engine = {};
 
         engine.render = engine.render.controller.create(engine.render);
         engine.world = World.create(engine.world);
+        engine.pairs = Pairs.create();
         engine.metrics = engine.metrics || Metrics.create();
         engine.input.mouse = engine.input.mouse || Mouse.create(engine.render.canvas);
         engine.mouseConstraint = engine.mouseConstraint || MouseConstraint.create(engine.input.mouse);
@@ -273,8 +267,8 @@ var Engine = {};
         // update pairs
         var pairs = engine.pairs,
             timestamp = engine.timing.timestamp;
-        Manager.updatePairs(pairs, collisions, timestamp);
-        Manager.removeOldPairs(pairs, timestamp);
+        Pairs.update(pairs, collisions, timestamp);
+        Pairs.removeOld(pairs, timestamp);
 
         // wake up bodies involved in collisions
         if (engine.enableSleeping)
@@ -340,8 +334,7 @@ var Engine = {};
     Engine.clear = function(engine) {
         var world = engine.world;
         
-        engine.pairs.table = {};
-        engine.pairs.list = [];
+        Pairs.clear(engine.pairs);
 
         World.addConstraint(engine.world, engine.mouseConstraint.constraint);
 

src/module/Outro.js

@@ -13,7 +13,7 @@ Matter.World = World;
 Matter.Contact = Contact;
 Matter.Detector = Detector;
 Matter.Grid = Grid;
-Matter.Manager = Manager;
+Matter.Pairs = Pairs;
 Matter.Pair = Pair;
 Matter.Resolver = Resolver;
 Matter.SAT = SAT;