View Full Version : Extensions, Multitexturing

Divide Overflow
08-22-2000, 02:01 AM
I can't get the multitexturing to work, I figured I've got it on my voodoo3 http://www.opengl.org/discussion_boards/ubb/smile.gif My testprogram gets stuck when it asks for the string length of extensions.

char *extensions=(char *)glGetStringGL_EXTENSIONS);
int len=strlen(extensions);

It seems the extensions returns a NULL pointer. Any help would be appreciated

--> Divide Overflow

"A wise man may look ridiculous in the company of fools."

08-22-2000, 03:57 AM
Make sure you have created a contex first. With wgl*() that is, if you are using Win32.

Divide Overflow
08-23-2000, 07:13 AM
Thanks ! I feel... ashamed somehow :P

But I now got the next problem. Multi Texturing calculates the color by c1*c2, but I want 2 pictures to fade into eachother ( a good old crossfade http://www.opengl.org/discussion_boards/ubb/biggrin.gif ) at the same location. Suggestions ?

Thanx !

--> Divide Overflow

DJ Tricky S
08-23-2000, 12:01 PM
to do a blend w/ texture alpha you can use the GL_DECAL texture function with glTexEnv() function call; to get a varying fade (varied alpha) there doesn't seem to be much built into the standard ARB multitexture extension, but with extensions such as nVidia's register combiners this is easy. Of course then it only works on nVidia hardware.