ios - 根据 Sprite 的当前位置让 Sprite 移动到某个位置？

Question

我认为我的标题相当困惑，但我不确定如何命名。这是我当前的代码:

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
SKAction *moveNodeRight = [SKAction moveByX:-209.0 y:0.0 duration:0.85];
 [_squirrelSprite runAction: moveNodeRight withKey:@"changeside"];
//_squirrelSprite.xScale = -1.0;

if(_squirrelSprite.xScale == -1.0)
{
    _squirrelSprite.xScale = 1.0;
} else {
    _squirrelSprite.xScale = -1.0;
}
}

当我点击屏幕时， Sprite 移动到一个新位置 (X:-209.0, Y:0.0)。新位置在当前位置的左侧。当我第二次点击屏幕时， Sprite 只是移动到离屏幕更远的左边。

我想要的:我对目前所拥有的感到满意，但是当 Sprite 处于新位置(X:-209.0，Y:0.0)时，我希望第二次点击将其返回到原始位置.我认为它看起来像上面的代码，但到目前为止没有任何效果。下面是它可能是什么样子的想法。谢谢!

if(_squirrelSprite.position == the second position)
{
    _squirrelSprite.position = the first position;
} else {
    _squirrelSprite.xScale = the second position;
}

Answer 1

当用户点击屏幕时，这会将节点从一个位置移动到另一个位置。然后，当用户再次点击屏幕时，它会将节点移回原始位置。

@interface MyScene()

@property SKSpriteNode *squirrelSprite;
@property BOOL atFirstPosition;
@property CGPoint firstPosition;

@end

@implementation MyScene

-(id)initWithSize:(CGSize)size
{
    if (self = [super initWithSize:size])
    {
        _firstPosition = CGPointMake(300, self.frame.size.height/2);
        _squirrelSprite = [SKSpriteNode spriteNodeWithColor:[SKColor blueColor] size:CGSizeMake(32, 32)];
        _squirrelSprite.position = _firstPosition;
        _atFirstPosition = YES;
        [self addChild:_squirrelSprite];
    }
    return self;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    if (_atFirstPosition)
    {
        SKAction *moveNodeLeft = [SKAction moveByX:-209.0 y:0.0 duration:0.85];
        [_squirrelSprite runAction: moveNodeLeft withKey:@"changeside"];
    } else {
        _squirrelSprite.position = _firstPosition;
    }
    _atFirstPosition = !_atFirstPosition;
    _squirrelSprite.xScale *= -1.0;
}

@end

编辑:这将使用 SKAction 将节点移回其原始位置

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    if (_atFirstPosition)
    {
        SKAction *moveNodeLeft = [SKAction moveByX:-209.0 y:0.0 duration:0.85];
        [_squirrelSprite runAction: moveNodeLeft withKey:@"moveleft"];
    } else {
        SKAction *moveNodeRight = [SKAction moveByX:209.0 y:0.0 duration:0.85];
        [_squirrelSprite runAction: moveNodeRight withKey:@"moveright"];
    }
    _atFirstPosition = !_atFirstPosition;
    _squirrelSprite.xScale *= -1.0;
}