这似乎是一个简单的问题,但我不能。正如标题所暗示的那样,我需要我的精灵根据它的方向更改为不同的纹理 - 左或右。这是我尝试做的:
if (self.sprite.position.x > 0) //also tried "self.sprite.position.x" instead of 0.
{
[self.sprite setTexture:[SKTexture textureWithImageNamed:@"X"]];
}
if (self.sprite.position.x < 0)
{
[self.sprite setTexture:[SKTexture textureWithImageNamed:@"XX"]];
}
两者都不起作用(除非精灵的 x 轴 == 0 -_-)。
我读过这个: 精灵套件:根据方向改变纹理它没有帮助。
编辑:对不起,我忘了提到精灵的移动在 2D 空间中是完全随机的。我为此使用 arc4random()。当它上升或下降时,我不需要任何纹理更改。但左和右是必不可少的。
我一定写错了什么:
if (self.sprite.physicsBody.velocity.dx > 0)
if (self.sprite.physicsBody.velocity.dx < 0)
对我不起作用。也不是
if (self.sprite.physicsBody.velocity.dx > 5)
if (self.sprite.physicsBody.velocity.dx < -5)
只是为了再次明确这个精灵的运动:它是在
-(void)update:(CFTimeInterval)currentTime
方法。这是这样实现的:
-(void)update:(CFTimeInterval)currentTime
{
/* Called before each frame is rendered */
if (!spritehMoving)
{
CGFloat fX = [self getRandomNumberBetweenMin:-5 andMax:5];
CGFloat fY = [self getRandomNumberBetweenMin:-5 andMax:7];
int waitDuration = arc4random() %3;
SKAction *moveXTo = [SKAction moveBy:CGVectorMake(fX, fY) duration:1.0];
SKAction *wait = [SKAction waitForDuration:waitDuration];
SKAction *sequence = [SKAction sequence:@[moveXTo, wait]];
[self.sprite runAction:sequence];
}
}
您可以检查fX
是大于还是小于 0,这意味着 x 轴上的"力"是正(右移动)或负(左移动)。
这是一个修改后的代码,应该可以解决问题-
顺便说一句-我还在移动的开始和结束时设置了SpritehMoving
BOOL
,否则,即使精灵正在移动,也会调用此方法(这没有任何问题,但它似乎击败了检查BOOL
值的目的。
if (!spritehMoving)
{
spritehMoving = YES;
CGFloat fX = [self getRandomNumberBetweenMin:-5 andMax:5];
CGFloat fY = [self getRandomNumberBetweenMin:-5 andMax:7];
int waitDuration = arc4random() %3;
SKAction *changeTexture;
if(fX > 0) { // Sprite will move to the right
changeTexture = [SKAction setTexture:[SKTexture textureWithImageNamed:@"RightTexture.png"]];
} else if (fX < 0) { // Sprite will move to the left
changeTexture = [SKAction setTexture:[SKTexture textureWithImageNamed:@"LeftTexture.png"]];
} else {
// Here I'm creating an action that doesn't do anything, so in case
// fX == 0 the texture won't change direction, and the app won't crash
// because of nil action
changeTexture = [SKAction runBlock:(dispatch_block_t)^(){}];
}
SKAction *moveXTo = [SKAction moveBy:CGVectorMake(fX, fY) duration:1.0];
SKAction *wait = [SKAction waitForDuration:waitDuration];
SKAction *completion = [SKAction runBlock:(dispatch_block_t)^(){ SpritehMoving = NO; }];
SKAction *sequence = [SKAction sequence:@[changeTexture, moveXTo, wait, completion]];
[self.sprite runAction:sequence];
}