使用最短角度旋转SpriteNode

Question

现在我的代码旋转了_eye以查看_me但是当_eye从359度旋转到1度时它不会通过359旋转 - ＆gt; 0 - ＆gt; 1，但它是359 - ＆gt; 358 - ＆gt; .. - ＆gt; 2 - ＆gt; 1。

#define SK_DEGREES_TO_RADIANS(__ANGLE__) ((__ANGLE__) * 0.01745329252f)
#define SK_RADIANS_TO_DEGREES(__ANGLE__) ((__ANGLE__) * 57.29577951f)

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    for (UITouch *touch in touches)
    {
        CGPoint location = [touch locationInNode:self];
        [_me runAction:[SKAction moveTo:location duration:0.5]];
    }
}

-(void)update:(CFTimeInterval)currentTime
{
    float deltaX = _me.position.x - _eye.position.x;
    float deltaY = _me.position.y - _eye.position.y;
    float angle = atan2f(deltaY, deltaX);

    [_eye runAction:[SKAction rotateToAngle:angle - SK_DEGREES_TO_RADIANS(90.0f) duration:0.2]];
}

Answer 1

要以最小的角度旋转精灵，请将shortestUnitArc添加到SKAction：

[_eye runAction:[SKAction rotateToAngle:angle - SK_DEGREES_TO_RADIANS(90.0f) duration:0.2 shortestUnitArc:YES]];

从Apple的文档中

  

shortestUnitArc

     

如果是，则以任何方式执行旋转   方向导致最小的旋转。如果否，则旋转   是插值的。