修复Vector2.zero引起的引用混乱问题

source/src/Utils/Timers/ITimer.ts

@@ -0,0 +1,20 @@
+module es {
+    export interface ITimer {
+        context: any;
+
+        /**
+         * 调用stop以停止此计时器再次运行。这对非重复计时器没有影响。
+         */
+        stop();
+
+        /**
+         * 将计时器的运行时间重置为0
+         */
+        reset();
+
+        /**
+         *
+         */
+        getContext<T>(): T;
+    }
+}

source/src/Utils/Timers/Timer.ts

@@ -0,0 +1,52 @@
+module es {
+    export class Timer implements ITimer{
+        public context: any;
+        public _timeInSeconds: number = 0;
+        public _repeats: boolean = false;
+        public _onTime: (timer: ITimer) => void;
+        public _isDone: boolean = false;
+        public _elapsedTime: number = 0;
+
+        public getContext<T>(): T {
+            return this.context as T;
+        }
+
+        public reset() {
+            this._elapsedTime = 0;
+        }
+
+        public stop() {
+            this._isDone = true;
+        }
+
+        public tick(){
+            // 如果stop在tick之前被调用，那么isDone将为true，我们不应该再做任何事情
+            if (!this._isDone && this._elapsedTime > this._timeInSeconds){
+                this._elapsedTime -= this._timeInSeconds;
+                this._onTime(this);
+
+                if (!this._isDone && !this._repeats)
+                    this._isDone = true;
+            }
+
+            this._elapsedTime += Time.deltaTime;
+
+            return this._isDone;
+        }
+
+        public initialize(timeInsSeconds: number, repeats: boolean, context: any, onTime: (timer: ITimer)=>void){
+            this._timeInSeconds = timeInsSeconds;
+            this._repeats = repeats;
+            this.context = context;
+            this._onTime = onTime;
+        }
+
+        /**
+         * 空出对象引用，以便在js需要时GC可以清理它们的引用
+         */
+        public unload(){
+            this.context = null;
+            this._onTime = null;
+        }
+    }
+}

source/src/Utils/Timers/TimerManager.ts

@@ -0,0 +1,32 @@
+module es {
+    /**
+     * 允许动作的延迟和重复执行
+     */
+    export class TimerManager extends GlobalManager {
+        public _timers: Timer[] = [];
+
+        public update() {
+            for (let i = this._timers.length - 1; i >= 0; i --){
+                if (this._timers[i].tick()){
+                    this._timers[i].unload();
+                    this._timers.removeAt(i);
+                }
+            }
+        }
+
+        /**
+         * 调度一个一次性或重复的计时器，该计时器将调用已传递的动作
+         * @param timeInSeconds
+         * @param repeats
+         * @param context
+         * @param onTime
+         */
+        public schedule(timeInSeconds: number, repeats: boolean, context: any, onTime: (timer: ITimer)=>void){
+            let timer = new Timer();
+            timer.initialize(timeInSeconds, repeats, context, onTime);
+            this._timers.push(timer);
+
+            return timer;
+        }
+    }
+}