I found a nasty bug with Radeon card: they don’t support mipmapping with a GL_TEXTURE_CUBE_MAP_ARB texture.
I tried with a Radeon1 64M DDR VIVO and Radeon 8500 64M (driver released 31 jan 2002) what it should be like the bug, using mipmapping
I think it’s an hardware limitation because the pb occurs with DirectX too !
So, thanks to ATI, we all have to do in our code:
if (strncmp(GLRendererString, “Radeon”, 6) == 0)
{//Radeon 1 and 8500 doesn’t support mipmap on CubeEnvMap (same pb for DirectX)
glTexParameteri(GL_TEXTURE_CUBE_MAP_ARB, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
}
else
{
glTexParameteri(GL_TEXTURE_CUBE_MAP_ARB, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
}
[This message has been edited by opla (edited 02-07-2002).]
It is true that the original Radeon does not support mip’d cube maps, although it should punt to the closest non mip’d min filter (e.g. if you ask for trilinear you would get bilinear). You shouldn’t see any corruption unless you depend on it being mip mapped.
As for the Radeon 8500, mip’d cube maps should work just fine. So that sounds like you might be seeing a driver bug…
Please send the app and I’ll take a look at it. Thanks.
raster, you seem to have a good experience with ATI cards.
can you tell me if there’s a size limit for GL_ATI_element_array ?
where can I found the spec for GL_ATI_element_array ?
I have another problem, using glDrawElementArrayATI(), some vertices are missing (works fine without glDrawElementArrayATI()), is there a size limit for this “index buffer” ?
Thanks to this topic I found out a problem I’ve seen with the whole 6xxx series of drivers, which I’ve also notified ATi about. I had a very simple app with a cubemap which ran very fast with 3286 drivers, but with the 6xxx series drivers I got a constant 40fps. If I changed th cubemap to something else like a 3d texture though it would run fast.
For some reason Jeff at ATi couldn’t reproduce the problem over there, it ran fast for him. Now after reading this topic I tried using plain GL_LINEAR instead and now cubemaps are fast again. I guess it’s time for ATi to look over their cubemap driver code
I reproduced the problem you were seeing with mip’d cubemaps. There were indeed two issues (a corruption and performance problem), both of which I just checked in a fix for. The fix will be in a future driver release. Thanks for reporting the bug…