I need to put a Blender object in a movie of r a school project, and it occasionally needs to be covered by a real object. In the Blender Tutorial guide it talks about making mask that covers the CG object, and shows the movie. What isn’t made clear is how to make the mask, mask the CG objects. So I’m asking how to do that. How do you make a mask that allows the movie to show through and cover the CG object?