How to bind custom volume fields in shader?

[sebastian_orosz]

Hi,

how can I bind/access a custom volume field within the current object in the shader? I can only see standard bindings on the Bindings tab in the VolumeGrid Shader.

Regards

[glacierise]

Look at the fields tab in the shader, you can see what volume gets bound to what shader component, and you can change it.

[glacierise]

Ah yes, it's called bindings in vray 5 which is more in line with Houdini convention

[sebastian_orosz]

Hi,

I need to bind additional fields to do some crazy math and use the result as input for the shader. In Arnold for example there are two nodes for binding additional float and vector fields: "Volume Sample Float" and "Volume Sample RGB". In Mantra you can simply use the "Bind" node et voila. Now since I'm using vray (obviously) I need to know how this can be done.

[glacierise]

Unfortunately we can't do that yet, as far as I know. It's extremely important, in being able to build your own shader, and last I saw it was announced that the volume tex shaders will be able to read a volume and the usual nodes will be able to be used and then plug the result in the shader, but it's not there yet.

It's important to get more voices supporting that, so a flexible volume shading pipeline shows up in V-Ray!

[hsz]

I would def support that, it would be great

[sebastian_orosz]

Maybe, as a "workaround", you could add some more bindings to the "Bindings" tab to drive other attributes, such as absorption color, which in my case is the reason for this thread. Then one could do the math outside the shader and bind the result in here:



I'm sure this can be done overnight, in the next nightlies? For tomorrow?

[glacierise]

Yeah that's another thing - there's no scattering in the current volume shader as far as I know either, which is sorely missing.

[doppelgaengerdigital]

any updates on this? shading volumes in vray should be improved a lot.

[ronald_a]

yes, +1 to every improvement mentioned here

[Dan Andersen]

+1. We render lots of volumes in VRay every day, and really could use an improved feature set as well..