Approximate rect after applying CATransform3D?

Question

I applied CATransform3D to a view. How can I find its approximate new frame after it?

I mean I applied a complex transform: rotation, translation, scale and perspective. And I need to find something like approximate minimal rect. I need it because this view is added to UIScrollView (to know the contentSize I need and of course to implement "scrollToItem:")

Answer 1

如果您希望获得完全包含此转换后视图的CGRect，则可以使用convertRect:toView:。例如：

CGRect rect = [viewWithTransforms convertRect:viewWithTransforms.bounds toView:self.view];

例如，灰色视图是一些变换后的UIView，黑色边框是上面显示的convertRect:toView:的结果：