openGL extensions

OpenGL OpenGL: Advanced Coding
1

Having trouble being able to use the glTextureColorMaskSGIS extension. The following returns error 127: The specified procedure could not be found. I am not really sure why I cannot use this extension - I have included glext.h and wglext.h Anyone have any ideas??

void *extproc;
extproc = (void *) wglGetProcAddress(“glTextureColorMaskSGIS”);

if (extproc == NULL) {
printf("Error %u
", GetLastError());
exit(0);
return;
}

2

Perhaps your hardware/driver doesn’t support it? Or perhaps you don’t have a valid GL context at the time?

3

I have the most recent OpenGLContext- how might I go about testing for validity?

4

Call glGetString(GL_EXTENSIONS) and make sure that the extension you are trying to use shows up in the extension list.

5

Just so you know, the GL_SGIS_texture_color_mask extension is probably not supported on any hardware other than SGI machines.

6

calling glGetString(GL_EXTENSIONS) returns (null) I bet i missed some step in installing the OpenGLContext.

7

(Assuming Win32)
Did you call wglMakeCurrent on a valid
context? Did you check the return value of wglCreateContext? Did you set a pixel format?