带AS3的滚珠跟踪鼠标

Question

我正在尝试用AS3做一个简单的游戏，类似于Tilt to Live。我试着让一个球跟随我的鼠标(另一个球)，这样当球接触到鼠标球时，你就会输。它一直给出错误，我真的不知道如何解决它。

到目前为止，这是我的游戏：

公共类Main扩展了Sprite {

    public function Main():void 
    {
    var vijand:Sprite = new Sprite ();
    vijand.graphics.beginFill(0xFFFF66) ; 
    vijand.graphics.drawCircle(30,30 ,30 );
    addChild(vijand);

    var vijand1:Sprite = new Sprite ();
    vijand1.graphics.beginFill(0xFFFF66) ; 
    vijand1.graphics.drawCircle(50,50 ,50 );
    addChild(vijand1);
    }

    public function beweeg(e:Event.):void
    {
    vijand.x = mouseX;
    vijand.y = mouseY;

    if (vijand.x > vijand1.x)
    {
        vijand1.x += 2;
    }


    if (vijand.y > vijand1.y)
    {
        vijand1.y += 2; 
    }



    if (vijand.x < vijand1.x)
    {
        vijand1.x -= 2; 
    }



    if (vijand.y < vijand1.y)
    {
            vijand1.y -= 2;
    }   

    }


    }

    }

Answer 1

我能看到的一个问题是你的'vijand‘和'vijand1’变量对于你的主构造函数是局部的。如果你想在主构造函数之外访问它们，你必须在构造函数之外声明它们，例如：

private var vijand:Sprite = new Sprite();
private var vijand1:Sprite = new Sprite();

public function Main():void 
    {
    ....

此外，'beweeg‘函数中也有一个拼写错误。删除“.”在‘Event’之后：

public function beweeg(e:Event):void
{
....

最后，您还需要一个事件侦听器来触发beweeg函数。可能是主构造函数中的ENTER_FRAME侦听器：

addEventListener(Event.ENTER_FRAME, beweeg);

Answer 2

var myBall:Shape = new Shape();
var enemyBall:Shape = new Shape();
var ballRadius:int = 8;
var dx:Number, dy:Number, radian:Number, speed:Number = 10;

myBall.graphics.beginFill(0x009900);
myBall.graphics.drawCircle(0, 0, ballRadius);

enemyBall.graphics.beginFill(0x990000);
enemyBall.graphics.drawCircle(0, 0, ballRadius);

addChild(myBall);
addChild(enemyBall);

//Place enemy at center
enemyBall.x = stage.stageWidth * 0.5;
enemyBall.y = stage.stageHeight * 0.5;

addEventListener(Event.ENTER_FRAME, onEnterFrame);

function onEnterFrame(e:Event):void {
    myBall.x = stage.mouseX;
    myBall.y = stage.mouseY;

    dx = myBall.x - enemyBall.x;
    dy = myBall.y - enemyBall.y;

    if (Math.sqrt(dx * dx + dy * dy) <= ballRadius * 2) {
        //NOOOOOoooooo
        //Game over
        removeEventListener(Event.ENTER_FRAME, onEnterFrame);
    } else {
        //Update enemy position
        //Every N ticks, increase speed, because it will be very easy game ;)
        radian = Math.atan2(dy, dx);
        enemyBall.x += Math.cos(radian) * speed;
        enemyBall.y += Math.sin(radian) * speed;
    }
}