触摸旋转精灵-Cocos2d

问题描述

| 有没有人有更好的方法来用一根手指旋转精灵？我的问题是，在将精灵完全旋转两次之后，我无法使它停止旋转，我会周期性地将屏幕翻转180度（self.rotation = 180;），然后再将其翻转回（self.rotation = 0）。但是，当我将其翻转到180度时，子画面将无法正确旋转。 有谁比这更好的主意？

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;
        }
    }

谢谢 编辑： 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，可以固定精灵的旋转，但是在旋转两整圈后仍然无法阻止精灵的旋转。     

解决方法

        在末尾添加新行：

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

这也许可以解决您的问题，因为角度将保持在360度范围内 用一根手指旋转的另一种方法是UIPanGestureRecognizer（但仍需要将角度保持在360度范围内）：

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];
  ...
}

请看一下本教程，以了解更多详细信息（它在拖动状态，但显示了如何进行平移手势）： http://www.raywenderlich.com/2343/how-to-drag-and-drop-sprites-with-cocos2d