I've just checked it. Unfortunately performance stays exactly the same.

Ough, sorry, I misread your post. I thought you wanted me to use one UBO what I'm already doing. Your idea makes sense, I will give it a try once I'm done with my current work :).

As I said, I'm already using one constant buffer...

Yes, I have only one constant buffer. Moreover, it is set only once so the code should not suffer any redundant API overhead. The only extra function I call for each iteration is glBufferSubData to...

Sorry for not being specific. But "switched to a constant buffer" I mean I have a constant buffer which only holds two matrices, world and viewProj. This constant buffer is updated before each draw...

First off I read this thread http://www.opengl.org/discussion_boards/showthread.php/170781-Uniform-Buffer-Objects-%28slow%29-help-needed but since the last post here comes from 2.5 yrs ago I thougt I...

Let's say I created a texture and its ID is 1. Now I bind this texture to a framebuffer with glFramebufferTexture2D.
Now let's say that at some point in runtime I destroyed this texture and created...

I probably should have checked the docs earlier but honestly this is very surprising it works this way. It is here if anyone is interested...

glGetUniformLocation returns a valid value. However, I noticed that when I want the matrix to be tranposed (and thus set the third arg. of glUniformMatrix to true) I get erros with glGetError,...

Then why do I get depth testing working correctly when I switch to an offscreen buffer with only color buffer attached? Moreover, z-values are correctly read for the *backbuffer's* z-buffer.

I've just spent an hour or two trying to get this code work:


float *tab = new float[16];
for (int i = 0; i < 16; i++)
tab[i] = 0.25f;
GLint uniformLocation =...

I read here (http://stackoverflow.com/questions/5279123/normal-back-buffer-render-to-depth-texture-in-opengl-fbos) that it is impossible to mix backbuffer with a custom GL framebuffer. I ran into...

This "imho" was dictated by the way D3D9 works. I just like when it's possible to expect the same behavior from OGL and D3D9.
But ok, if it's what the spec says I'm not gonna argue :).
Thanks for...

Why would that be improper? With D3D9 it works this way. Imho OGL should set base level "under the hood" and expected it to have done so with Texture2D. So actually I though it's a driver bug with...

1. I don't see anything regarding mip-mapping or cube maps.
2. Why with texture2D I don't need provide a full mipmap chain, and with cube textures I need?

Hey,

I generate a cube map texture, assign it 3 mipmaps (although the texture can hold up to 9, it's 256x256) and try to render a mesh with that texture. Unfortunately, I see black triangles.
...

Ok. Thanks for the clarification. Whom should I turn to with information about misleading GL doc statement?

Yup, you're right. But here: http://www.opengl.org/sdk/docs/man/xhtml/glTexParameter.xml we read:
"For OpenGL versions 1.3 and greater, or when the ARB_multitexture extension is supported,...

I'm having a weird problem. What I want: use one texture in one fragment shader (GLSL) using two different sampling modes, this case let it be nearest and linear on min/mag/mip. So the code:

...

That's great. Thanks!

Afaik anisotropic filtering requires not only 4x scaled down mipmaps of original image (that is, from 128x128 it would be 64x64, 32x32, ..., 1x1) but also other sizes, like 128x16 (in case of 8x...

Hm, I guess that LODs, since they can be negative, allows to set greater level of detail such that greater mipmaps can still be seen in further distance. However, there is also a state of glTexEnv...

Okay, so I can still use glTexImage. And what about automatic mipmap generation on hardware? By default, all mipmaps are generated. Does any of these functions can force GPU to generate only a...

So the LEVEL functions determine which mipmaps should be loaded into the GPU? This way if I set, for instance, only the first mipmap by setting these values to 0 and 1, then a texture in GPU takes...

I'm wondering what is the actual difference between these two code snippets:


glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_LOD, LODBias);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LOD,...