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Ninja
06-28-2002, 05:12 AM
I want to make some cool bumpmaps with per-pixel lighting and stuff like that. But it must be as HW-independent as possible. Is it possible to do that with CG or do I have to wait for OG2.0?
(I'm thinking about the extensions that is usually used for bump-maps and so on..)

SirKnight
06-28-2002, 06:12 AM
If you use the Direct 3D profiles for Cg then you can do bump mapping w/ Cg that should run on multiple cards. The OpenGL profile right now only supports nvidia. Plus right now the OpenGL fragment profile is not working. If no other vendors implement Cg then looks like GL2 will be the way to go once it comes out.

-SirKnight

Ninja
06-28-2002, 08:48 AM
Ok, thanks for your answer!
So the D3D-profile supports multiple cards, but the OpenGL-profile don't?
Why is that so?

-Ninja

knackered
06-28-2002, 09:01 AM
...because d3d supports pixel shaders on multiple cards through a standard interface - cg just makes calls into this interface, so it's irrelevent what card its running on, so long as it supports pixel shaders. Unfortunately, OpenGL does not have a standard vendor-independent interface, and so other vendors (such as ATI, and 3dlabs) would have to write profiles for the Cg compiler to work with opengl. Sad but true.

zed
06-28-2002, 01:11 PM
dot3_arb (part of opengl1.3) will let u do bumpmapping (works on *all cards)

*newer ones eg radeon/gf