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DarkWIng
12-05-2002, 10:36 AM
could someone please explain why the following line works:
glFinalCombinerInputNV( GL_VARIABLE_A_NV, GL_PRIMARY_COLOR_NV, GL_UNSIGNED_INVERT_NV, GL_ALPHA );
but this one dosn't
glFinalCombinerInputNV( GL_VARIABLE_A_NV, GL_SECONDARY_COLOR_NV, GL_UNSIGNED_INVERT_NV, GL_ALPHA );
It just gives me totay white color. Both colors are loaded with same values. I'm running WinXP/GF4-4600/Detonator 40.71

Any idea? Driver bug?


[This message has been edited by DarkWIng (edited 12-05-2002).]

Old GLman
12-05-2002, 10:41 AM
Is the EXT_secondary_color extension even available?
Are you using glSecondaryColor3fEXT() or one of its variants to specify a color?

EDIT: Sorry http://www.opengl.org/discussion_boards/ubb/biggrin.gif, must be supported... GF4

[This message has been edited by Old GLman (edited 12-05-2002).]

Old GLman
12-05-2002, 10:44 AM
Plus you cant use the same variable for two different inputs.

DarkWIng
12-05-2002, 10:46 AM
I've tried both. Trough glSecondaryColor3fEXT and trough vertex programs. The result is the same.
I should make some other points. It works for RGB part, but not for ALPHA. This is the problem.

bakery2k
12-05-2002, 11:00 AM
The secondary color does not have an alpha component. That is why there are only SecondaryColor3 entry points and not SecondaryColor4. This applies even with vertex programs.

Old GLman
12-05-2002, 11:02 AM
The only other thing I can think of right now is that maybe your forgetting to send alpha values?? Also, you have to use two different variables. If you use A and B, it will take the alpha values you send for use in the final combiner equation. I believe that any rgb values you send have no effect if your using the alpha component.

EDIT: Ah I forgot about that, your have to devise another way to do what you want.

[This message has been edited by Old GLman (edited 12-05-2002).]