Can a plane be made transparent, but still receive shadows?
I can see how you can create a plane, another object (particles, Text, Another Video Layer, etc) and a light and get shadows to appear. I believe you can map an image or texture onto a plane as well.
But can I have a video of a room (leaving it as a 2D layer), place a 3D layer on the ground (where it appears in the video), and then have shadows appear on the floor with correct placement of lights, etc.
For this to work the ground layer has to be transparent for the video to show through, but still receive and shadows. I could then put this layer on a wall for example and get the same effect.
Is this available and I'm just not seeing it? Or am I on the wrong track for this kind of effect?