Hello all,

We encountered a serious performance problem with FBOs on NVidia hardware (tested on 8800GT, 8800GTX and 9800GT, WinXP 32 SP3). The issue seems to have suddenly appeared around driver...

Absolutely nothing. As far as I see it, the story is a complete over-reaction, and contains a lot of technical misunderstandings and misinterpretations.

First, MS will in fact ship Windows...

I doubt that patent issues are of major interest for the original poster, this sounds more like a hobbyist or learning project than anything he actually wants to distribute (I might be wrong, of...

This worked well for me, and is reasonably simple :



Oh yes: and if your matrix is guaranteed to only encode a rotation in the upper 3x3 part, you could of course use a simple transpose....

Cass, thanks a lot, that was exactly the information I was looking for.

Yes, I was in fact using a single large mapped and partitioned VBO, legacy from a quick'n'dirty VAR to VBO conversion....

Thanks for your reply.


Well, the idea with mapping was to avoid the redundant copy glBufferDataARB & co will introduce. The data is compressed in main memory, and is sequentially decompressed...

Anyone ?

I have encountered a serious problem with the ARB_vertex_buffer_object extension on nVidia hardware. Specs are as follows: GF4 Ti4600 AGPx4, 53.03 drivers on Win2k, VIA KT600, Athlon XP 2800.

The...

OK, the emissive colour thing did it. Thanks for pointing that out !

I have to do some performance tests, though. I wrote a quick vertex program to do the effect, and this one is extremely fast on...

> Ambient won't work anyway because it's independant of distance.

Well, the specs say that attenuation is done on all 3 components of the light, including ambient.

> As for normals, just...

Thanks for your suggestions.

Nutty, I tried this interesting idea, though with the small modification, that I have an 'attenuation mipmap' only on the alpha channel. I use this one to blend...

Hello,

I'm currently doing some vertex based detail texturing for my terrain engine. Basically, I'm blending the textures on unit 0 and 1 using vertex alpha. The equation is c = CTex0 *...

> Is there any reason to use 16bit framebuffer anymore?

Some customers want that option, no matter what.

- Alex

Are you sure about that ? We run some tests of our current title on a range of nVidia cards a few weeks ago. GeForce3 seemed to perform fine in 16 bit colour depth, but the other didn't.
...

I don't think an octree would be a good idea for a general terrain renderer.

Octrees are a good choice for geometry with a bounding volume approaching the 1:1:1 ratio measured along the x,y and z...

It doesn't need to be very much. If framerate drops at 119.5 Hz instead of 120, vsync will already sync you on 60 Hz. The small difference can come from the additional transfer overhead due to the...

Yes, and this is why I recommended *natural* mergesort. This is a non-recursive variant of mergesort, that performs O(n) on already sorted lists, with a worst case behaviour of O(n log2 n) on...

And AFAIK, that would be natural mergesort.

- Alex

Thanks, I will try that out. The error term looks a bit weird to me, I'm afraid it will have a rather large impact on the expected result. It probably depends on the characteristics of the textures...

Yes, the ARB_texture_env_crossbar is very interesting, I think I could get the exact equation using it. I never heard about it before, since I'm developing on a GeForce, and as you said, nVidia...

Yes, right. That's why I thought that an advanced tex combine extension could circumvent the problem of this old OpenGL limitation. Apparently newer manufacturer specific extension can do that (see...

Hi

I have a small problem getting the blending mode I want using ARB/EXT_texture_env_combine and multi-texturing.

I would like to get this TexEnv function: Cv = Cf * (Ct0 + Ct1)

In other...