When I have a patch layer above two layers, the patch layer stays on the same position on the screen when I animate the parts it patches. It doesn't follow the part it should hide. Is this correct behaviour and should I move that layer as well, or do I have to do something else?
Yes, you have to move the patch with the animation. If you are using bones it's easy enough to bind the patch layer to the appropriate bone which make using the patch much easier.
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