Hi!

I realy can't get my head around this one

Simple vdb volume rendering issue.

Image 1 everithing is ok

Image 2 set some color on the cloud color material parameter everithing is ok

Image 3 set parameter back to white and connect to cloud color (diff) a color constant (red) with the same value as before, oups the opacity is overriden

Image 4 seeing that Cd is multiplied by diff inside the shader, I connect my color constant to it (green this time)same punnishment as before… it renders all the active tiless of the vdb qith a density of 1…

Any clue, workearound very appreciated…

Thanks in advence.

You didn't promote density. You can't plug stuff into proper shaders without also passing all bound attributes/fields as well.

Create a parameter node for density, and connect to the density input of the material builder.

nice thanks a lot

But is it only the case with volume shaders? I don't have to connect other parameters (like normal for instance) in a surface shader when I use a custom parm ..

This is the case will all shaders (nodes that output surface/displace). Normal and Position are exempt; they are global variables, not bound attributes. UV, color (Cd), and alpha are all bound attributes and would need to be passed as parameters as well.

re thanks I'm a little less ignorant, now!

Cheers