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MPech
04-24-2002, 04:39 AM
I'm looking for the equivalent of glBlendFunc() when using multitexturing extension.

I would like to act upon the blend function when using my two hardware texture units.

is it possible ?

Bob
04-24-2002, 05:17 AM
You mean blend the two textures together, so you can draw several textures in one pass insteda of multiple passes?

The equivalent of glBlendFunc would then be the texture environment functions. For "basic" texture environment functions (which in fact is quite powerful), have a look at the texture env combine (http://oss.sgi.com/projects/ogl-sample/registry/ARB/texture_env_combine.txt) extensions (a part of OpenGL 1.3 also, if I remember correct). It's a specification document, not a tutorial, but it's quite good and you should be able to understand it.

MPech
04-24-2002, 08:14 AM
thanks, but I can't find any Tutorial or HowTo on this topic.
Does anybody knows a reliable on ?

regards

Bob
04-24-2002, 11:27 AM
You could always try this (http://nehe.gamedev.net) site.

cyrfer
07-21-2010, 05:45 PM
I know this is old, but will someone describe the settings needed to get the effect the OP requested? NeHe doesn't show you, and I don't think there is a recipe anywhere on the internet. The problem is understanding all the options with glTexEnv(), the documentation is vague.

ZbuffeR
07-22-2010, 12:00 AM
Check "Multi-Texture Blending" here for a code sample :
http://www.codesampler.com/oglsrc/oglsrc_4.htm

(btw I would not say the documentation is vague ...)

cyrfer
07-22-2010, 11:15 AM
I ran the demo and looked at the code. I believe the use of glTexEnv[i/f] answers the OP's question. I have my own questions, and the documentation is not answering them. Thanks for the response.