hello,

i am having a problem when rendering my displacement shader with an ambient occlussion surface shader i get big black areas in my mush. iAlso i am rendering with renderman. Any help would be much apreciated.

Thanks
Bazazi

have you set your displacement bounds in the render tab?

yes.

Can you post the .sl you're using?
and/or a link to a rendered image?

surface occlusion(float samples = 64)
{
normal Nn = normalize(N);

float hits = 0;
gather (“illuminance”, P, Nn, PI/2, samples, “distribution”, “cosine”) {
hits += 1;
}
float occ = hits / samples;

Ci = (1 - occ) * Cs * Os;
Oi = Os;
}

This is the shader. I can get it to work by editing the .RIB manually by including the lines:
Attribute “trace” “bias” 0.03
Attribute “trace” “displacements” 1
But i dont know where to find those options in houdini.

try adding the line to the camera's pre-include field. You
can find it under the camera's render tab.

Thanks. That worked like a baby!