Shadows->CG onto live

[MiloMindbender]

Figure out how catch the shadows of CG objects and apply them to a live video background. This is for when you want to composite a CG character or prop with a live video so the CG character is standing on the live floor.

This will depend on matching the CG lighting setup with the live video lighting so the shadows in both are similar, ray tracing will probably be required for soft shadows.