三角函数

//弧度=角度*Math.PI/180;



//角度=弧度*180/Math.PI;



var speed:Number = 5;

addEventListener(Event.ENTER_FRAME,onEnterFrame);

function onEnterFrame(event:Event):void

{

	var dx:Number = mouseX - ball.x;

	var dy:Number = mouseY - ball.y;

	var angle:Number = Math.atan2(dy,dx);

	var dist:Number = Math.sqrt(dx * dx + dy * dy);

	ball.rotation = angle * 180 / Math.PI;

	var vx:Number = Math.cos(angle) * speed;

	var vy:Number = Math.sin(angle) * speed;

	ball.x +=  vx;

	ball.y +=  vy;

}