Simply removing the check "solved" the problem, since the extension works without incident. I still find it extremely strange that this was happening though and I'm curious what could have caused it....

I have the following code:



GLenum err = glewInit();
cerr << glGetString(GL_EXTENSIONS) << "\n";
if (err != GLEW_OK ||
!glewIsSupported("GL_ARB_color_buffer_float...

Thanks, that did it! At least the glReadPixels is now working. I'm still getting some results which I don't understand on the stenciling itself, but I'll ask about that tomorrow if I haven't worked...

I tried this instead:
glReadPixels(0,0,900,900,GL_DEPTH_STENCIL_EXT,GL_UNSIGNED_INT_24_8_EXT,&amp;ints[0]);

But I'm still getting the invalid operation error.

There are no OpenGL errors prior to the glReadPixels().

Am I sure the FBO has a packed depth/stencil attachment? Fairly certain, but not 100%. Is there a glGet() I can use to check? My FBO setup...

I've got a bunch of triangles, of 3 different types. I want to render the first two types of triangles, and then render the third type----but I only want fragments to be drawn for the third type on...

It's not a remote display, it's the local one.

Further developments: Turns out that glxinfo reports the correct extensions in csh, but not in bash (nor in csh run within bash)! Any idea what could...

On a Linux machine, I can see the ARB_color_buffer_float extension in the list of supported extensions if I open the NVIDIA X Server Settings program. However, if I run glxinfo from a console (or any...

No. Though I'm curious as to the circumstances that would require such a function.
[/QUOTE]

I'm working on an "Image Buffer" hierarchy. The concrete class type could represent a Renderbuffer...

Is it possible to test whether two OpenGL contexts are currently sharing display lists and textures?

Ideally I'd like a cross-platform answer, but if either WGL or GLX offers such a query, I'd be...

I have a framebuffer object with a single floating point renderbuffer attached to color buffer 0.

I do a glDrawBuffer/glWindowPos(0,0)/glDrawPixels() combo at several points in my program in order...

Let's say I've got a retangular prism and I'd like to generate uniform normals for each face, straight outward.

If I didn't care about normals, then I could use glDrawElements() to render it,...

Well, I don't see a glDrawBuffer() call there.

Ah-ha---I knew that as soon as I posted I'd solve my own problem.....

When you consider that gluPerspective() is probably just called glFrustum() internally, it becomes clear that the math won't...

Most of my work with OpenGL has been using orthographic projection. Now I need perspective projection, and things rather mysteriously aren't working, and I'm not sure why.

I have some dummy code...

I'm trying to design a reasonably high-performance OpenGL wrapper for a specific geometry-once, render-many case.

Past experience has shown me that on NVIDIA hardware at least, display lists can...

I actually had stumbled on the "multiple render additive blending" option, but the fractional blending and multitexture avenues didn't occur to me. Thanks, I'll check them out.

Okay, I figured out that I don't really need to use lighting----just setting the glColor() will allow me to control the texture intensity.

Well, it will let me *dim* the texture intensity....

Turns out I had GL_LIGHTING enabled when I didn't want it. They were just getting washed out.

I haven't done a lot with gluQuadrics, but I thought a gluDisk or two might be just what I needed for a particular display.

However, when I draw the gluDisk(), it comes out white, no matter what...

I'd like to apply a multiplier to every texel of a texture while displaying it on a 2D rectangle. This would be trivial if I used a fragment program, but I'm trying to do this with minimal OpenGL...

VirtualGL is nice to know about, but it does the opposite of what I need in this case.

It actually doesn't have a GPU at all.



I don't care about performance right now, I just want it to work.



Looks interesting, but too much of a dependency to add to my current project....

When I print out glGetString(GL_VERSION) on a locally-run program, I get "2.1.2".

If I print it out on the server, I get "1.2 (2.1.2)".

Does this mean that the server's OpenGL driver isn't as...

I've got an 8-core Linux server that I'd like to run an OpenGL program on. The trouble is, it uses some advanced extensions like EXT_framebuffer_object.

I have the DISPLAY variable set to my local...