Iphone 使用CATTransferM3D透视图的折纸过渡

我试图在两个UIView上实现一种折纸转换，只使用层功能。这个想法是用透视效果折叠两个视图。两个视图都有一个透视图，过渡由每个视图上的旋转以及一个视图上的平移来定义，从而使该视图似乎附加到另一个视图

问题是，在过渡时期，这一观点相互重叠。我不想使用zPosition来避免这种重叠，我真的希望这两个视图的行为就像它们被共享的一方绑定在一起一样。下面是转换的代码

有什么想法或其他解决方案吗

- (void)animateWithPerspective
{
    CGFloat rotationAngle = 90;
    CATransform3D transform = CATransform3DIdentity;
    UIView *topView;
    UIView *bottomView;
    UIView *mainView;
    CGRect frame;
    CGFloat size = 200;

    mainView = [[UIView alloc] initWithFrame:CGRectMake(10,10, size, size*2)];
    [self.view addSubview:mainView];
    bottomView = [[UIView alloc] initWithFrame:CGRectZero];
    bottomView.layer.anchorPoint = CGPointMake(0.5, 1);
    bottomView.frame = CGRectMake(0, size, size, size);
    bottomView.backgroundColor = [UIColor blueColor];
    [mainView addSubview:bottomView];

    topView = [[UIView alloc] initWithFrame:CGRectZero];
    topView.layer.anchorPoint = CGPointMake(0.5, 0);
    topView.frame = CGRectMake(0, 0, size, size);
    topView.backgroundColor = [UIColor redColor];
    [mainView addSubview:topView];

    transform.m34 = 1.0/700.0;
    topView.layer.transform = transform;
    bottomView.layer.transform = transform;

    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:2];
    [UIView setAnimationRepeatAutoreverses:YES];
    [UIView setAnimationRepeatCount:INFINITY];
    [UIView setAnimationCurve:UIViewAnimationCurveLinear];
    frame = bottomView.frame;
    frame.origin.y = bottomView.frame.origin.y - bottomView.frame.size.height - topView.frame.size.height;
    bottomView.frame = frame;
    topView.layer.transform = CATransform3DRotate(transform, rotationAngle * M_PI/180, 1, 0, 0);
    bottomView.layer.transform = CATransform3DRotate(transform, -rotationAngle * M_PI/180, 1, 0, 0);
    [UIView commitAnimations];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self animate];
}

为了简化问题，让我们去掉任何透视变换。下面是一个具有相同问题的简单代码：

- (void)animateWithoutPerspective
{
    CGFloat rotationAngle = 90;
    UIView *topView;
    UIView *bottomView;
    UIView *mainView;
    CGRect frame;
    CGFloat size = 200;

    mainView = [[UIView alloc] initWithFrame:CGRectMake(10,10, size, size*2)];
    [self.view addSubview:mainView];
    bottomView = [[UIView alloc] initWithFrame:CGRectMake(0, size, size, size)];
    bottomView.backgroundColor = [UIColor blueColor];
    [mainView addSubview:bottomView];

    topView = [[UIView alloc] initWithFrame:CGRectZero];
    topView.layer.anchorPoint = CGPointMake(0.5, 0);
    topView.frame = CGRectMake(10, 0, size-20, size);
    topView.backgroundColor = [UIColor redColor];
    [mainView addSubview:topView];

    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:2];
    [UIView setAnimationRepeatAutoreverses:YES];
    [UIView setAnimationRepeatCount:INFINITY];
    [UIView setAnimationCurve:UIViewAnimationCurveLinear];
    frame = bottomView.frame;
    frame.origin.y = bottomView.frame.origin.y - bottomView.frame.size.height;
    bottomView.frame = frame;
    topView.layer.transform = CATransform3DMakeRotation(rotationAngle * M_PI/180, 1, 0, 0);
    [UIView commitAnimations];
}

---

起初我认为Y位置的线性变换并不意味着旋转的线性变换，但似乎是这样

误差非常简单，透视值是错误的，透视图是通过在Z轴上以负距离定位观测台来建模的。然后您需要否定透视值：

transform.m34 = 1.0/(-700.0);

它确实像预期的那样工作

为了记录在案，角度的变换不是线性的。但是这件文物被zbuffer藏了起来

---

在中间路径的角度将是60度，但与线性动画，我们得到45度。但从右侧看，从负Z轴位置看，缓冲区隐藏平面交点。

最后，这里是添加简单阴影的三袖动画的一些解决方案。解决这种动画的关键是使用几个组织良好的子层以及一些

catTransferMLlayer

- (void)animate
{
    CATransform3D transform = CATransform3DIdentity;
    CALayer *topSleeve;
    CALayer *middleSleeve;
    CALayer *bottomSleeve;
    CALayer *topShadow;
    CALayer *middleShadow;
    UIView *mainView;
    CGFloat width = 300;
    CGFloat height = 150;
    CALayer *firstJointLayer;
    CALayer *secondJointLayer;
    CALayer *perspectiveLayer;

    mainView = [[UIView alloc] initWithFrame:CGRectMake(50, 50, width, height*3)];
    mainView.backgroundColor = [UIColor yellowColor];
    [self.view addSubview:mainView];

    perspectiveLayer = [CALayer layer];
    perspectiveLayer.frame = CGRectMake(0, 0, width, height*2);
    [mainView.layer addSublayer:perspectiveLayer];

    firstJointLayer = [CATransformLayer layer];
    firstJointLayer.frame = mainView.bounds;
    [perspectiveLayer addSublayer:firstJointLayer];

    topSleeve = [CALayer layer];
    topSleeve.frame = CGRectMake(0, 0, width, height);
    topSleeve.anchorPoint = CGPointMake(0.5, 0);
    topSleeve.backgroundColor = [UIColor redColor].CGColor;
    topSleeve.position = CGPointMake(width/2, 0);
    [firstJointLayer addSublayer:topSleeve];
    topSleeve.masksToBounds = YES;

    secondJointLayer = [CATransformLayer layer];
    secondJointLayer.frame = mainView.bounds;
    secondJointLayer.frame = CGRectMake(0, 0, width, height*2);
    secondJointLayer.anchorPoint = CGPointMake(0.5, 0);
    secondJointLayer.position = CGPointMake(width/2, height);
    [firstJointLayer addSublayer:secondJointLayer];

    middleSleeve = [CALayer layer];
    middleSleeve.frame = CGRectMake(0, 0, width, height);
    middleSleeve.anchorPoint = CGPointMake(0.5, 0);
    middleSleeve.backgroundColor = [UIColor blueColor].CGColor;
    middleSleeve.position = CGPointMake(width/2, 0);
    [secondJointLayer addSublayer:middleSleeve];
    middleSleeve.masksToBounds = YES;

    bottomSleeve = [CALayer layer];
    bottomSleeve.frame = CGRectMake(0, height, width, height);
    bottomSleeve.anchorPoint = CGPointMake(0.5, 0);
    bottomSleeve.backgroundColor = [UIColor grayColor].CGColor;
    bottomSleeve.position = CGPointMake(width/2, height);
    [secondJointLayer addSublayer:bottomSleeve];

    firstJointLayer.anchorPoint = CGPointMake(0.5, 0);
    firstJointLayer.position = CGPointMake(width/2, 0);

    topShadow = [CALayer layer];
    [topSleeve addSublayer:topShadow];
    topShadow.frame = topSleeve.bounds;
    topShadow.backgroundColor = [UIColor blackColor].CGColor;
    topShadow.opacity = 0;

    middleShadow = [CALayer layer];
    [middleSleeve addSublayer:middleShadow];
    middleShadow.frame = middleSleeve.bounds;
    middleShadow.backgroundColor = [UIColor blackColor].CGColor;
    middleShadow.opacity = 0;

    transform.m34 = -1.0/700.0;
    perspectiveLayer.sublayerTransform = transform;

    CABasicAnimation* animation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.x"];
    [animation setDuration:2];
    [animation setAutoreverses:YES];
    [animation setRepeatCount:INFINITY];
    [animation setFromValue:[NSNumber numberWithDouble:0]];
    [animation setToValue:[NSNumber numberWithDouble:-90*M_PI/180]];
    [firstJointLayer addAnimation:animation forKey:nil];

    animation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.x"];
    [animation setDuration:2];
    [animation setAutoreverses:YES];
    [animation setRepeatCount:INFINITY];
    [animation setFromValue:[NSNumber numberWithDouble:0]];
    [animation setToValue:[NSNumber numberWithDouble:180*M_PI/180]];
    [secondJointLayer addAnimation:animation forKey:nil];

    animation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.x"];
    [animation setDuration:2];
    [animation setAutoreverses:YES];
    [animation setRepeatCount:INFINITY];
    [animation setFromValue:[NSNumber numberWithDouble:0]];
    [animation setToValue:[NSNumber numberWithDouble:-90*M_PI/180]];
    [bottomSleeve addAnimation:animation forKey:nil];

    animation = [CABasicAnimation animationWithKeyPath:@"bounds.size.height"];
    [animation setDuration:2];
    [animation setAutoreverses:YES];
    [animation setRepeatCount:INFINITY];
    [animation setFromValue:[NSNumber numberWithDouble:perspectiveLayer.bounds.size.height]];
    [animation setToValue:[NSNumber numberWithDouble:0]];
    [perspectiveLayer addAnimation:animation forKey:nil];

    animation = [CABasicAnimation animationWithKeyPath:@"position.y"];
    [animation setDuration:2];
    [animation setAutoreverses:YES];
    [animation setRepeatCount:INFINITY];
    [animation setFromValue:[NSNumber numberWithDouble:perspectiveLayer.position.y]];
    [animation setToValue:[NSNumber numberWithDouble:0]];
    [perspectiveLayer addAnimation:animation forKey:nil];

    animation = [CABasicAnimation animationWithKeyPath:@"opacity"];
    [animation setDuration:2];
    [animation setAutoreverses:YES];
    [animation setRepeatCount:INFINITY];
    [animation setFromValue:[NSNumber numberWithDouble:0]];
    [animation setToValue:[NSNumber numberWithDouble:0.5]];
    [topShadow addAnimation:animation forKey:nil];

    animation = [CABasicAnimation animationWithKeyPath:@"opacity"];
    [animation setDuration:2];
    [animation setAutoreverses:YES];
    [animation setRepeatCount:INFINITY];
    [animation setFromValue:[NSNumber numberWithDouble:0]];
    [animation setToValue:[NSNumber numberWithDouble:0.5]];
    [middleShadow addAnimation:animation forKey:nil];
}

---

菲尔回答的快速版本

func animate() {
    var transform:CATransform3D = CATransform3DIdentity;
    var topSleeve:CALayer
    var middleSleeve:CALayer
    var bottomSleeve:CALayer
    var topShadow:CALayer
    var middleShadow:CALayer
    var mainView:UIView
    var width:CGFloat = 300
    var height:CGFloat = 150
    var firstJointLayer:CALayer
    var secondJointLayer:CALayer
    var perspectiveLayer:CALayer

    mainView = UIView(frame:CGRectMake(50, 50, width, height*3))
    mainView.backgroundColor = UIColor.yellowColor()
    view.addSubview(mainView)

    perspectiveLayer = CALayer()
    perspectiveLayer.frame = CGRectMake(0, 0, width, height*2)
    mainView.layer.addSublayer(perspectiveLayer)

    firstJointLayer = CATransformLayer()
    firstJointLayer.frame = mainView.bounds;
    perspectiveLayer.addSublayer(firstJointLayer)

    topSleeve = CALayer()
    topSleeve.frame = CGRectMake(0, 0, width, height);
    topSleeve.anchorPoint = CGPointMake(0.5, 0)
    topSleeve.backgroundColor = UIColor.redColor().CGColor;
    topSleeve.position = CGPointMake(width/2, 0)
    firstJointLayer.addSublayer(topSleeve)
    topSleeve.masksToBounds = true

    secondJointLayer = CATransformLayer()
    secondJointLayer.frame = mainView.bounds;
    secondJointLayer.frame = CGRectMake(0, 0, width, height*2)
    secondJointLayer.anchorPoint = CGPointMake(0.5, 0)
    secondJointLayer.position = CGPointMake(width/2, height)
    firstJointLayer.addSublayer(secondJointLayer)

    middleSleeve = CALayer()
    middleSleeve.frame = CGRectMake(0, 0, width, height);
    middleSleeve.anchorPoint = CGPointMake(0.5, 0)
    middleSleeve.backgroundColor = UIColor.blueColor().CGColor
    middleSleeve.position = CGPointMake(width/2, 0)
    secondJointLayer.addSublayer(middleSleeve)
    middleSleeve.masksToBounds = true

    bottomSleeve = CALayer()
    bottomSleeve.frame = CGRectMake(0, height, width, height)
    bottomSleeve.anchorPoint = CGPointMake(0.5, 0)
    bottomSleeve.backgroundColor = UIColor.grayColor().CGColor
    bottomSleeve.position = CGPointMake(width/2, height)
    secondJointLayer.addSublayer(bottomSleeve)

    firstJointLayer.anchorPoint = CGPointMake(0.5, 0)
    firstJointLayer.position = CGPointMake(width/2, 0)

    topShadow = CALayer()
    topSleeve.addSublayer(topShadow)
    topShadow.frame = topSleeve.bounds
    topShadow.backgroundColor = UIColor.blackColor().CGColor
    topShadow.opacity = 0

    middleShadow = CALayer()
    middleSleeve.addSublayer(middleShadow)
    middleShadow.frame = middleSleeve.bounds
    middleShadow.backgroundColor = UIColor.blackColor().CGColor
    middleShadow.opacity = 0

    transform.m34 = -1/700
    perspectiveLayer.sublayerTransform = transform;

    var animation = CABasicAnimation(keyPath: "transform.rotation.x")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = -90*M_PI/180
    firstJointLayer.addAnimation(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "transform.rotation.x")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = 180*M_PI/180
    secondJointLayer.addAnimation(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "transform.rotation.x")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = -90*M_PI/180
    bottomSleeve.addAnimation(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "bounds.size.height")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = perspectiveLayer.bounds.size.height
    animation.toValue = 0
    perspectiveLayer.addAnimation(animation, forKey: nil)


    animation = CABasicAnimation(keyPath: "position.y")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = perspectiveLayer.position.y
    animation.toValue = 0
    perspectiveLayer.addAnimation(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "opacity")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = 0.5
    topShadow.addAnimation(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "opacity")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = 0.5
    middleShadow.addAnimation(animation, forKey: nil)
}

---

来说明答案

我没有把所有的动画和透视投影（透视层.sublayerTransform放在它的

catTransformLayer

子层上）。播放投影矩阵m34字段值，查看其如何影响消失点

Swift 4更新答案： Vojtec答案的更新版本

    func animate() {
    var transform:CATransform3D = CATransform3DIdentity;
    var topSleeve:CALayer
    var middleSleeve:CALayer
    var bottomSleeve:CALayer
    var topShadow:CALayer
    var middleShadow:CALayer
    var mainView:UIView
    let width:CGFloat = 300
    let height:CGFloat = 150
    var firstJointLayer:CALayer
    var secondJointLayer:CALayer
    var perspectiveLayer:CALayer

    mainView = UIView(frame:CGRect(x: 50, y: 50, width: width, height: height*3))
    mainView.backgroundColor = UIColor.yellow
    view.addSubview(mainView)

    perspectiveLayer = CALayer()
    perspectiveLayer.frame = CGRect(x: 0, y: 0, width: width, height: height*2)
    mainView.layer.addSublayer(perspectiveLayer)

    firstJointLayer = CATransformLayer()
    firstJointLayer.frame = mainView.bounds;
    perspectiveLayer.addSublayer(firstJointLayer)

    topSleeve = CALayer()
    topSleeve.frame = CGRect(x: 0, y: 0, width: width, height: height)
    topSleeve.anchorPoint = CGPoint(x: 0.5, y: 0)
    topSleeve.backgroundColor = UIColor.red.cgColor
    topSleeve.position = CGPoint(x: width/2, y: 0)
    firstJointLayer.addSublayer(topSleeve)
    topSleeve.masksToBounds = true

    secondJointLayer = CATransformLayer()
    secondJointLayer.frame = mainView.bounds;
    secondJointLayer.frame = CGRect(x: 0, y: 0, width: width, height: height*2)
    secondJointLayer.anchorPoint = CGPoint(x: 0.5, y: 0)
    secondJointLayer.position = CGPoint(x: width/2, y: height)
    firstJointLayer.addSublayer(secondJointLayer)

    middleSleeve = CALayer()
    middleSleeve.frame = CGRect(x: 0, y: 0, width: width, height: height);
    middleSleeve.anchorPoint = CGPoint(x: 0.5, y: 0)
    middleSleeve.backgroundColor = UIColor.blue.cgColor
    middleSleeve.position = CGPoint(x: width/2, y: 0)
    secondJointLayer.addSublayer(middleSleeve)
    middleSleeve.masksToBounds = true

    bottomSleeve = CALayer()
    bottomSleeve.frame = CGRect(x: 0, y: height, width: width, height: height)
    bottomSleeve.anchorPoint = CGPoint(x: 0.5, y: 0)
    bottomSleeve.backgroundColor = UIColor.gray.cgColor
    bottomSleeve.position = CGPoint(x: width/2, y: height)
    secondJointLayer.addSublayer(bottomSleeve)

    firstJointLayer.anchorPoint = CGPoint(x: 0.5, y: 0)
    firstJointLayer.position = CGPoint(x: width/2, y: 0)

    topShadow = CALayer()
    topSleeve.addSublayer(topShadow)
    topShadow.frame = topSleeve.bounds
    topShadow.backgroundColor = UIColor.black.cgColor
    topShadow.opacity = 0

    middleShadow = CALayer()
    middleSleeve.addSublayer(middleShadow)
    middleShadow.frame = middleSleeve.bounds
    middleShadow.backgroundColor = UIColor.black.cgColor
    middleShadow.opacity = 0

    transform.m34 = -1/700
    perspectiveLayer.sublayerTransform = transform;

    var animation = CABasicAnimation(keyPath: "transform.rotation.x")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = -90*Double.pi/180
    firstJointLayer.add(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "transform.rotation.x")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = 180*Double.pi/180
    secondJointLayer.add(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "transform.rotation.x")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = -90*Double.pi/180
    bottomSleeve.add(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "bounds.size.height")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = perspectiveLayer.bounds.size.height
    animation.toValue = 0
    perspectiveLayer.add(animation, forKey: nil)


    animation = CABasicAnimation(keyPath: "position.y")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = perspectiveLayer.position.y
    animation.toValue = 0
    perspectiveLayer.add(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "opacity")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = 0.5
    topShadow.add(animation, forKey: nil)

    animation = CABasicAnimation(keyPath: "opacity")
    animation.duration = 2
    animation.autoreverses = true
    animation.repeatCount = 1000
    animation.fromValue = 0
    animation.toValue = 0.5
    middleShadow.add(animation, forKey: nil)
}
}

---

非常感谢您将CATTransferMlayer放在我的雷达上。在咬牙切齿之后，我终于得到了结果。。当我尝试同样的垂直方向时，我得到了反向视图动画。。我已经发布了链接。。你能给我一些帮助吗你能解释一下不同层之间的关系吗？为什么它是这样工作的？