Hello all,

I created a object I apply a volume shader on it and I want to use my alpha texture to guide the density of the volume density(from 0 (no density) to 1 (full density). I am using renderman and houdini, I tried the to plug and to play with attributes but I have no idea how to proceed. thank you

Hey

Is the texture in the UV space of the object? How do you want the texture to extrapolate into the inside of the object? Or is the volume in the shape of the surface of the object?

Hi Honza thank you for your reply,

The Volume is the shape of the surface object.

I want to use a texture as a alpha, the same way you plug a texture into the opacity of your shader.

I am using renderman, the volume shader doesnt reconise the uvs of the object. I tried to use the projection but I didnt manage to make it work.

is ther a way to sore the Cd with a attribut from map > call it inthe shader system through a primvar and use it to drive the density ?
thanks

Aah, I see. I actually misunderstood, sorry. I guess building to volume from geometry with the texture as an attribute driving the density is not what you want...

Also I don't know or have Renderman, but in Karma I could kind of plugin a texture into a shader with point cloud lookups. Once again probably not exactly what you want, but maybe closer? There has to be something similar in Renderman.

A terrible answer, I know



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