package {
 
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.events.MouseEvent;
    import flash.ui.Mouse;
    import flash.ui.MouseCursor;
    import flash.geom.Rectangle;
     
 
    public class AngleBounce extends Sprite {
 
        private var ball:Ball;
        private var line:Sprite;
        private var gravity:Number=0.25;
        private var bounce:Number=-0.6;
        private var rect:Rectangle;
 
        public function AngleBounce() {
            init();
        }
 
        private function init():void {
            Mouse.cursor=MouseCursor.BUTTON;
            ball=new Ball(10);
            addChild(ball);
            ball.x=100;
            ball.y=100;
            line=new Sprite  ;
            line.graphics.lineStyle(1);
            line.graphics.lineTo(300,0);
            addChild(line);
            line.x=50;
            line.y=200;
            line.rotation=25;//将line旋转形成斜面
            stage.addEventListener(MouseEvent.MOUSE_DOWN,MouseDownHandler);
             
            rect = line.getBounds(this);//获取line的矩形边界
             
            graphics.beginFill(0xefefef)
            graphics.drawRect(rect.left,rect.top,rect.width,rect.height);
            graphics.endFill();
        }
 
        private function MouseDownHandler(e:Event) {
            addEventListener(Event.ENTER_FRAME,EnterFrameHandler);
        }
 
        private function EnterFrameHandler(e:Event):void {
 
            //line.rotation = (stage.stageWidth/2 - mouseX)*0.1;
 
            //普通的运动代码 
            ball.vy+=gravity;
            ball.x+=ball.vx;
            ball.y+=ball.vy;
             
             
            /*//只有二者(的矩形边界)碰撞了才需要做处理
            if (ball.hitTestObject(line)) {*/
             
            //也可以换成下面的方法检测          
            if (ball.x > rect.left && ball.x < rect.right && ball.y >rect.top && ball.y < rect.bottom){
                 
                //trace("true");
             
                //获得角度及正余弦值 
                var angle:Number=line.rotation*Math.PI/180;
                var cos:Number=Math.cos(angle);
                var sin:Number=Math.sin(angle);
 
                //获得 ball 与 line 的相对位置 
                var dx:Number=ball.x-line.x;
                var dy:Number=ball.y-line.y;
 
                //反向旋转坐标(得到ball“相对”斜面line的坐标)
                var x2:Number=cos*dx+sin*dy;
                var y2:Number=cos*dy-sin*dx;
 
                //反向旋转速度向量(得到ball“相对”斜面的速度) 
                var vx2:Number=cos*ball.vx+sin*ball.vy;
                var vy2:Number=cos*ball.vy-sin*ball.vx;
 
                //实现反弹 
                if (y2>- ball.height/2) {
                    y2=- ball.height/2;
                    vy2*=bounce;
                    //将一切再正向旋转回去
                    dx=cos*x2-sin*y2;
                    dy=cos*y2+sin*x2;
 
                    ball.vx=cos*vx2-sin*vy2;
                    ball.vy=cos*vy2+sin*vx2;
 
                    //重新定位
                    ball.x=line.x+dx;
                    ball.y=line.y+dy;
                }
            }
 
            //跑出舞台边界后将其重新放到原始位置
            if (ball.x>=stage.stageWidth-ball.width/2||ball.y>=stage.stageHeight-ball.height/2) {
                ball.x=100;
                ball.y=100;
                ball.vx=0;
                ball.vy=0;
                removeEventListener(Event.ENTER_FRAME,EnterFrameHandler);
            }
        }
    }
 
}