ios - 我可以进行半个 m34 转换吗

Question

我想做一个完整的旋转，但在中途交换图像，我似乎无法做到这一点。完整的旋转可以在下面看到。我怎么能用漂亮的 z 轴东西做一半呢？这是在 animateWithDuration block 中 (iOS4)

// Create perspective transformation
CATransform3D transform = CATransform3DIdentity;
transform.m34 = 1.0f / -zDistance;
myView.layer.transform = transform; //- 3d
myView.layer.transform = CATransform3DMakeRotation(M_PI, -1, 0, 0); 

Answer 1

你可以用两个 block 来做到这一点:

// Rotate the second 'backside' view to 90 degrees and hide it
CATransform3D transform = CATransform3DIdentity;
transform.m34 = 1.0f / -zDistance;
mySecondView.layer.transform = transform;
mySecondView.layer.transform = CATransform3DMakeRotation(M_PI / 2, -1, 0, 0);
mySecondView.hidden = YES;

// Animate to 90 degrees
[UIView animateWithDuration:0.5 animations:^{
    CATransform3D transform = CATransform3DIdentity;
    transform.m34 = 1.0f / -zDistance;
    myView.layer.transform = transform;
    myView.layer.transform = CATransform3DMakeRotation(M_PI / 2, -1, 0, 0);

} completion:^{

    // Switch to the backside view
    myView.hidden = YES;
    mySecondView.hidden = NO;

    // Animate the remaining 90 degrees
    [UIView animateWithDuration:0.5 animations:^{
        CATransform3D transform = CATransform3DIdentity;
        transform.m34 = 1.0f / -zDistance;
        mySecondView.layer.transform = transform;
        mySecondView.layer.transform = CATransform3DMakeRotation(M_PI, -1, 0, 0);
    }
}

您还可以尝试使用 myView.layer.isDoubleSided 属性，它隐藏 View 的背面 - 尽管您仍然需要在动画结束，否则第一个 View 的按钮仍可点击。

希望对您有所帮助!谢谢。