please help me......

i want to know how to write the code in pixel shader to compute the squared difference between pixels using the register combiners.
please help me i am in great need.

alankritha

I don’t think your question i very valid in the beginners forum…

you can’t write a “pixel shader”(its acutally called “fragment shader” in openGL) to setup the register combiners.
register combiners are set up using various gxTexEnv calls.
take a look at following extensions:

for register combiners: http://oss.sgi.com/projects/ogl-sample/registry/NV/register_combiners.txt http://oss.sgi.com/projects/ogl-sample/registry/ARB/texture_env_combine.txt http://oss.sgi.com/projects/ogl-sample/registry/ARB/texture_env_crossbar.txt

for fragment programs: http://oss.sgi.com/projects/ogl-sample/registry/ARB/fragment_program.txt

Moving thread to the shaders forum. Someone there may give you specific help.