volume texture issue

M

maphit

New member
Hi there,
I'm trying to use volume textures with Direct X 8.1 (debug version), but i get a crash after a call to swapBuffer : the system freeze. It only happens when i try to draw something using a 3d texture. There are no error messages in the log.
The problem is that it works with the reference rasterizer.
I'm using a 64*64*64 3d texture A8R8G8B8, with no mipmaps
My 3d board is a Radeon 32mb ddr.
I have tried several releases of the drivers, but it doesn't works..

Has anyone experienced that problem ?

Thanks :)
 
Hi,
The DX sample works. In fact the problem appears when i draw volume textures and other kind of primitives too. One strange thing, is that i tried to launch my app again yesterday, with the same drivers, and no code changes, and it seemed to work.. strange.. (i'm using catalyst 2.1). However, i still can't do a volume texture + another texture (as i understood 1 volume texture count for 2 textures on radeon 7xxx, so i should be able to use a third one ?). The same happens : when swap buffers is called, it freezes. One other things is that i tried to install the catalyst 2.2, but the sample RadeonShadowShader stopped to work (i got a black screen). Moreover, the sample EMBMSoftReflect stopped to works too (i can see the teapot, but i see no floor at all), so i switched back to the 2.1.
One interesting thing is that i never had prb with OpenGL samples, they all worked great through driver releases..

Regards,

Maphit
 
RadeonCubeVolViz?

RadeonCubeVolViz?

Does RadeonCubeVolViz run on your system without these side effects? How are you using your cube map differently (i.e. creation, state when rendering etc) than RadeonCubeVolViz?

-Jason
 
Yes this sample works. I want to use volume texture to do per-pixel lighting in the following way :

1 - first pass i setup attenuation in alpha using a volume texture
2 - second pass i render specular bump with EMBM additively, and with modulation with frame buffer alpha. In addition to EMBM i use a texture with a black and a white texel to prevent backfacing faces to be lighted.
3 - third pass i render texture modulated by diffuse lighting (dp3 with no normalization). This is added to the frame buffer and modulated by frame buffer alpha too.
Then i repeat this process for every light

This allow to have high specular exponent even on a radeon 7xxx (i just modulate x & y of the light vector after putting it in tangent space to approximate different exponents), but the problem is that i use both a normal map and a dudv map for the same bump texture. What I wanted to do is to use a dudv map only, so i need to store backfacing information in the frame buffer by modulating the volume texture by the 2 pixel texture, because i can't remove backfacing during the diffuse pass (4 texture needed ..). Unfortunatly, trying to use a 3d texture modulated by another texture doesn't works..
Of course getting a 8500 would solve my problem, but I think i can get a decent result event on Radeon 7xxx.
 
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