Question

有没有人有更好的方法用一根手指旋转精灵？我的问题是，我无法让精灵在完全旋转两次后停止旋转，我将屏幕周期旋转180度（self.rotation = 180;）然后将其翻转（self.rotation = 0）。但是，当我将它翻转到180度时，精灵将无法正常旋转。

任何人都有比这更好的想法吗？

CGFloat gRotation;

- (void)update:(ccTime)delta
{
    g.rotation = gRotation;
}
    - (void)ccTouchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
    {
        UITouch *touch = [touches anyObject];
        CGPoint location = [touch locationInView:[touch view]];
        location = [[CCDirector sharedDirector] convertToGL:location];

        if (CGRectContainsPoint(g.boundingBox, location))
        {
            CGPoint firstLocation = [touch previousLocationInView:[touch view]];
            CGPoint location = [touch locationInView:[touch view]];

            CGPoint touchingPoint = [[CCDirector sharedDirector] convertToGL:location];
            CGPoint firstTouchingPoint = [[CCDirector sharedDirector] convertToGL:firstLocation];

            CGPoint firstVector = ccpSub(firstTouchingPoint, g.position);
            CGFloat firstRotateAngle = -ccpToAngle(firstVector);
            CGFloat previousTouch = CC_RADIANS_TO_DEGREES(firstRotateAngle);

            CGPoint vector = ccpSub(touchingPoint, g.position);
            CGFloat rotateAngle = -ccpToAngle(vector);
            CGFloat currentTouch = CC_RADIANS_TO_DEGREES(rotateAngle);

            gRotation += currentTouch - previousTouch;
        }
    }

由于

修改的

我进入GameConfig.h并将#define GAME_AUTOROTATION kGameAutorotationUIViewController更改为#define GAME_AUTOROTATION kGameAutorotationNone

然后，进入AppDelegate.m并将#if GAME_AUTOROTATION == kGameAutorotationUIViewController更改为#if GAME_AUTOROTATION == kGameAutorotationNone

当我翻转屏幕时修正了精灵的旋转，但是在两次完整旋转后我仍然无法停止精灵的旋转。

Answer 1

在最后添加一个新行：

gRotation += currentTouch - previousTouch;
gRotation = fmod(gRotation,360.0); // <<< fix the angle

这可能会解决您的问题，因为角度将保持在360范围内

用一根手指旋转的其他方法是UIPanGestureRecognizer（但您仍然需要将角度保持在360范围内）：

UIPanGestureRecognizer *gestureRecognizer = [[[UIPanGestureRecognizer alloc] initWithTarget:layer action:@selector(handlePanFrom:)] autorelease];
[[[CCDirector sharedDirector] openGLView] addGestureRecognizer:gestureRecognizer];

...

- (void)handlePanFrom:(UIPanGestureRecognizer *)recognizer 
{
  CGPoint translation = [recognizer translationInView:recognizer.view];
  ...
}

请查看本教程以获取更多详细信息（关于拖动，但显示如何执行平移手势）：

http://www.raywenderlich.com/2343/how-to-drag-and-drop-sprites-with-cocos2d

触摸旋转雪碧 - Cocos2d

1 个答案: