The proc_square is a giant square that can be made into any color. Great for doing mattes. Isolating a character by placing a black behind them. It has soft edges on 2 sides so that you can create anime style looking shots ala robotech et al.

Newscript
Put character_boots on a path

On another path BEHIND BOOTS
newent=proc_square;floor=0
This origin point is right in the middle of the square. It usually has to be scaled up pretty big. AND it definitely needs a focus path, usually the camera.

Put a cmd node at 2.0
procval=0xffffffff

This will turn it all white. It uses the exact same 8 digit hex code as the FLASH command.

Try some other colors and Alpha!