I am a CG student currently learning Houdini and Renderman.
Does anyone know how I can render rhe occlusion pass with renderman in Houdini?

I did try to make a occlusion shader in Vex builder. But it worked only in Mantra. The same way does not work in Rman. Does anyone know hoe I can make it work in rman?

Thank you for your attention!

why cant you just use the supplied ratOcclusion shader? Just make sure you pass the trace set in the specific page of the rman rop to the rib to add the “trace” “visibility” attribute to your objects. This turns on raytracing for your geometry

tallkien,

I applied the ratOcclusion shader but it does not work. The objects appeared to be flat white. how do i pass the trace set in the specific page of the rman rop to the rib to add the “trace” “visibility” attribute to thr objects?

thanks

In the specific page somewhere near the bottom you have a field called “trace visible” or “visible trace” or like, not sure, not near houdini/rman right now. this adds the “Attribute” “visibility” “trace” to objects. Having a “*” in that field should add it to all objects.

Also check if you have rat/lib/shaders in your shader path field

If your scene is raytracing( rendering slower) then I think you should play with the shader params (hope you've made the Dialog script) . If its all rendering flat white i suspect it is working, AFAIRemember occlusion has some distance based params that need to be tweaked (max distance or something like that)

Thanks a lot tallkien!
It works! I got it!
Besides, can I bake the occlusion data with that shader?

thanks again!

hi guys i'm using houdini 8 with renderman 11.5 and i can't find a <<field called “trace visible” or “visible trace” or like>>in the specific tab of the renderman ROP

help would be appreciated