¿Cómo rotar un UIImageView con CATransform3DRotate hace un efecto como la apertura de la puerta?

Question

He leído y probar este article (Opening door effect using Core Animation)

Y Implementar siguiente código en mi aplicación:

CALayer *layer = threeHomeView.layer; 
CATransform3D initialTransform = threeHomeView.layer.transform; 
initialTransform.m34 = 1.0/-900; 

[UIView beginAnimations:@"Scale" context:nil]; 
[UIView setAnimationDuration:3]; 
layer.transform = initialTransform; 
CATransform3D rotationAndPerspectiveTransform = threeHomeView.layer.transform; 

rotationAndPerspectiveTransform = CATransform3DRotate(rotationAndPerspectiveTransform 
                 , 40.0f * M_PI/180.0f 
                 , 0.0f 
                 , 1.0f 
                 , 0.0f); 
layer.transform = rotationAndPerspectiveTransform; 

[UIView setAnimationDelegate:self]; 
[UIView setAnimationDidStopSelector:@selector(threeHomeFlyOut)]; 
[UIView commitAnimations]; 

threeHomeView es un UIImageView.

MI PREGUNTA ES: la imagen solo puede rotar en la línea vertical media de la imagen, pero quiero que gire en la línea vertical izquierda de la imagen.

Answer 1

Use CATransform3DRotate como lo hizo en combinación con CATransform3DTranslate para girar alrededor del borde, como hice en this answer. He aquí un pequeño fragmento (que tendrá que modificar esto para sus propios usos):

CATransform3D t = CATransform3DIdentity; 
t = CATransform3DTranslate(t, 0, -self.view.bounds.size.height/2, 0); 
t = CATransform3DRotate(t, rec.scale * M_PI, 1, 0, 0); 
t = CATransform3DTranslate(t, 0, -self.view.bounds.size.height/2, 0); 
self.view.layer.transform = t; 

Answer 2

- (void)awakeFromNib { 

    transformed = [CALayer layer]; 

    transformed.frame = self.bounds; 

    [self.layer addSublayer:transformed]; 

    CALayer *imageLayer = [CALayer layer]; 

    imageLayer.frame = CGRectMake(10.0f, 4.0f, 300.0f, 226.0f); 

    imageLayer.transform = CATransform3DMakeRotation(20.0f * M_PI/180.0f, 
                1.0f, 0.0f, 0.0f); 

    imageLayer.contents = (id)[[UIImage imageNamed:@"IMG_0051.png"] CGImage]; 

    [transformed addSublayer:imageLayer]; 

    imageLayer = [CALayer layer]; 

    imageLayer.frame = CGRectMake(10.0f, 234.0f, 300.0f, 226.0f); 

    imageLayer.transform = CATransform3DMakeRotation(-20.0f * M_PI/180.0f, 
                1.0f, 0.0f, 0.0f); 

    imageLayer.contents = (id)[[UIImage imageNamed:@"IMG_0089.png"] CGImage]; 

    [transformed addSublayer:imageLayer]; 

} 

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { 

    previousLocation = [[touches anyObject] locationInView:self]; 

} 

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { 

    CGPoint location = [[touches anyObject] locationInView:self]; 

    // BJL: The following is the code I used in Molecules to do 3-D rotation 

    CATransform3D currentTransform = transformed.sublayerTransform; 

    CGFloat displacementInX = location.x - previousLocation.x; 

    CGFloat displacementInY = previousLocation.y - location.y; 


    CGFloat totalRotation = sqrt(displacementInX * displacementInX + displacementInY * displacementInY); 

    CATransform3D rotationalTransform = CATransform3DRotate(currentTransform, totalRotation * M_PI/180.0, 
                    ((displacementInX/totalRotation) * currentTransform.m12 + (displacementInY/totalRotation) * currentTransform.m11), 
                    ((displacementInX/totalRotation) * currentTransform.m22 + (displacementInY/totalRotation) * currentTransform.m21), 
                    ((displacementInX/totalRotation) * currentTransform.m32 + (displacementInY/totalRotation) * currentTransform.m31)); 

    previousLocation = location; 

    transformed.sublayerTransform = rotationalTransform; 

}