子视图从（x,y）到（-x,y）

开发的游戏中，需要子视图从位置(x, y)沿着抛物线滑到位置(width-x, y)，应该怎么实现？

下面是代码的摘录：

- (void)ccTouchEnded:(UITouch *)touch withEvent:(UIEvent *)event
{
    CGSize screenSize = [[CCDirector sharedDirector] winSize];

    if(!self.anim.flipY){
        self.anim.position = ccp(screenSize.width - self.anim.position.x, self.anim.position.y);
        self.anim.flipY = true;
    }
    else{
        self.anim.position = ccp(screenSize.width - self.anim.position.x, self.anim.position.y);
        self.anim.flipY = false;
    }

}