Can a real world light be ambient and diffuse at the same time? I don't see how since an ambient light does not come from any particular direction but a diffuse light does. Maybe you can clear this confusion up for me. Any help would be greatly appreciated! Edited by - Viscous-Flow on August 31, 2001 5:00:48 AM

There isn''t really such a thing as an ''ambient'' light in the real world.

Ambient lighting is simulating the fact that light should reflect off of every object in the scene, but we don''t usually want to do all those calculations. This is what lights the areas under tables, desks, etc that don''t have a line of sight to a light in the real world.

Before people started using ambient lights in computers, the undersides of tables in a brightly lit room would be pitch black!

Of course, if you do model the reflections off of the walls and other objects you don''t need ambient lighting. Global illumination schemes like high order raytracing or the radiosity algorithm don''t need ambient lights.

What CheeseGrater said is correct, but this will also help you out:

For basic cgi lighting -

You should only have 1 ambient light in your scene. It should be pure ambient, no diffuse or anything. It''s color should be dark red or blue or any color according to the mood.

All your other lights shouldn''t cast any ambient light.

Also, sometimes you may not need an ambient light at all.