Cube map sampling problem

h21 · May 25, 2002, 5:43am

Hi,
I’m trying to sample normalization cube map in such way:
glSampleMapATI (GL_REG_2_ATI,GL_TEXTURE2_ARB,GL_SWIZZLE_STR_ATI);
But I obtain some crap (it looks just like cube maps texturing is disabled, but it is enabled!). I am pretty sure that the problem is in this shader (i.e. texture stages setup is correct) since when I’m doing same things in FF pipeline it works.
Does someone have an idea what is wrong? Your help is highly appreciated. I’m stuck with it for several days

[This message has been edited by h2 (edited 05-25-2002).]

PH1 · May 25, 2002, 5:53am

The above line should work. Make sure you expand the vector using ( GL_BIAS_BIT_ATI | GL_2X_BIT_ATI ) in your dotproduct calculations ( I assume you want to do bumpmapping / per-pixel lighting ).

h21 · May 25, 2002, 6:03am

The problem isn’t in dotproduct. For example this shader does not work as it should be:
glSampleMapATI (GL_REG_2_ATI,GL_TEXTURE2_ARB,GL_SWIZZLE_STR_ATI);
glColorFragmentOp1ATI (MOV_ATI,GL_REG_0_ATI,0,0,GL_REG_2_ATI,0,0);

PH1 · May 25, 2002, 6:13am

Hmmm, that’s strange. Did you remember to enclose the shader in calls to glBeginFragmentShaderATI() and glEndFragmentShaderATI() ?

davepermen · May 25, 2002, 6:49am

how about showing the whole code?

and the general statement: make sure u use the newest drivers

h21 · May 25, 2002, 8:11am

Ok, guys. If you think that such sampling command is OK for cubemaps, I’ll continue hunting bugs in my code. Thanks for help!

PH1 · May 25, 2002, 10:02am

I tried the above shader with a normalization cubemap bound to texture2 and the results were as expected, so the problem must be elsewhere - anyway, have a nice bug hunt .