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davepermen
03-18-2001, 07:27 AM
are in the register combiners the previous colors accessable? i mean the "dst_color" in the blendfunc, the fragment color whatever http://www.opengl.org/discussion_boards/ubb/smile.gif

and when not, how is it combined with blending?

mark?

Lars
03-18-2001, 01:29 PM
The combiners only affect the blending until alphablending is done. This means you can only change the way textures and diffuse colors are blended together.
In detail you have the following :

primary color (thru Vertex)
secondary color (thru vertex)
texture0 color
texture1 color
...
texture7 color
fog color
constant color
second constant color

Hope this helps.

Lars

mcraighead
03-18-2001, 03:37 PM
No, the destination color is not accessible until the blending stage in the pipeline. The combiners are well before that.

- Matt

davepermen
03-19-2001, 07:05 AM
ok, then it is like that:

srccolor = registercombineroperation( primary,secondary,tex0to7,fog,cc0/1);

dstcolor = blendoperation( srccolor, dstcolor );

? like that?

Jorrit
03-20-2001, 03:07 AM
That's right