Type-o -- I mean to say shared/std140.

The uniform block size is constant for shared regardless of which uniforms were used in the shader and the compiler isn't changing the offsets or sizes for...

I've run across a change in the Nvidia 319/320 series drivers with regards to std140/packed uniform buffer objects that is causing havoc in our application.



#version 150

layout(shared)...

You're leaving an element of gl_FragData[] uninitialized in the A and B cases, which isn't a good idea. Since you have additive blending enabled, just initialize the unused gl_FragData[] element with...

Points are shared in a mesh between adjacent triangles, whereas vertex data is unique per vertex/triangle pair. Our app allows users to set attribute data at four different levels - geometry...

I was pretty excited to see AMD_interleaved_elements, until I read the implementation and realized I'd be limited to at most 16b indices. And for a per-face, per-point, per-vertex setup, the limit is...

Does turning point sprite on and off to force square points work better for AMD cards? (the multisample problem sounds like a driver bug).

If the GL_PACK_ALIGNMENT is greater than 4, it'll also cause a crash if the scanline size isn't divisible by the GL_PACK_ALIGNEMENT (int align=0; glGetIntegerv(GL_PACK_ALIGNMENT, &align); ). It...

Not that I'm adverse to any of the suggestions above, I can see cases where they would be useful. But in the interests of discussion, if it changes rarely, would drawing them as separate batches with...

This isn't exactly the right spot to ask, User Hardware/Software & Gaming help would be a bit more appropriate.

Have you tried disabling Window's Aero?

I wasn't rebutting, just making the point that this can be done now using a geometry shader with similar performance characteristics. This suggestion just becomes a convenience.

This would effectively make this suggestion, "make gl_PrimitiveID accessible in the vertex shader", which means that the vertex shader would not be able to cache vertices, and instead run on every...

Yes, you can toggle multisample on and off as you render. However you probably don't want to do this frequently, as it may produce very small batches. If you're doing this only once per render for...

I ran into a similar issue when rendering point cloud data as tiny quads to approximate a surface. I used glEnable(GL_POINT_SPRITE) to force the points to render as quads again, but I'm not sure if...

What graphics hardware are you running? It may not support separate left and right buffers. For example, I believe windowed quad-buffer stereo is only supported on Quadro and not GEForce cards.

Yet it's been shown in several threads that VAOs are measurably slower in many cases, so this doesn't give me a lot of faith that the driver is doing something smart. It almost seems like it has been...

I believe the problem with using VAOs is the lack of distinction between "bind for modify" and "bind for draw". Because the driver has no idea what you're going to do, it has to set up all the state...

Have you tried adding EndPrimitive() to the end of the geometry shader? Also, are you setting the maximum number of output vertices to at least 3 via glProgramParameteri()?

AMD alphabetizes their vertex attributes when assigning vertex attribute locations, while Nvidia assigns them in the order they are declared in the shader. In the Compatibility profile, you must have...

Even the GTX690 has FP64 performance that is 1/24th that of its FP32 performance. That is a lot of performance loss.

If you need to pass a dvec4 position to a tessellation or geometry shader...

Reading your post again, it's definitely my bad reading comprehension, not your clarity. My apologies.

With instancing, the vertex shader is run multiple times over the vertices of the same base...

Those extensions are designed for the shader pipeline only. Generic vertex attributes require a shader to interpret them, and glVertexAttribDivisor() can only be applied to generic vertex attributes...

Sadly, in some cases, yes.

I know of one major studio that was complaining of performance issues with our GL3 renderer, and it turned out all the animators were running Nvidia GT210 cards, which...

glNormalPointer, glColorPointer and glVertexPointer were introduced in GL1.1, and VBOs in GL 1.5, so you can use them.

You just can't use Vertex Array Objects (VAOs), as those are GL 3.0, unless...

No, it doesn't. It's a GL 2.1 GPU. You need an Intel HD series GPU to get OpenGL 3.x.

You can do exactly that.