I have a very peculiar problem with 3D reflector. To illustrate it I've drawn a (very!) simple diagram showing the problem.
I make a 3D floor layer (grey), and then add a vertical 3D wall layer (black) and then add an After Effects camera (green). I select the floor layer and then go to Effects/3D Reflector and as I would expect, I see a reflection of the wall (black) on the floor layer (grey).
However the problem appears if I put another 3D layer - in this case, a small solid (blue) BEHIND the wall. Viewing the wall from the camera position, you cannot see the blue solid as it is behind the wall layer of course, BUT the solid appears in the reflection on the floor! I can't figure out why this should be. Is it a bug, or am I forgetting something?
I know I could set the solid behind the wall to be a vampire layer but I do not want to do this as the layer will eventually be moving in front of the wall and I will want to reflect it, and besides, surely 3D Reflector shouldn't be reflecting items that should be out of sight?