Cannot render multiple volumes in one geo container

[jkunz07]

Hey, I have three vdb grids in one geo container.  Instead of all being named 'density', they each have unique names: 'a', 'b', 'c'.

I cannot find a way to get them all to render   Only the first primitive (primnum #0) renders and the rest won't show up.  I've tried changing the vm_volumequalitychannel to a blank string, *, and some other entries but none seem to work.

 

Anyone know if I've done something wrong, or is this a bug?

multiple_volumes_render_all.v1.hip

[rbowden]

Well, the obvious question would be do you need to have unique names for each one? If not, couldn't you just do a vdbfrompolygons after the merge?

BUT, I suppose the purpose of this is to find out why it isn't working and honestly, I can't figure it out either. The closest thing I got was putting a convertVDB after the merge. Doing that, I got a little bit of the sphere to show up which tells me that this could be a bounds issue? Definitely interesting and I feel like I am missing something here also.

[jkunz07]

One reason is to have a 'temperature' volume which renders in areas with no 'density', like a smoking fire.  This should work, but I think it broke a while ago.

I've attached an example of this which doesn't currently work.

 

The case I illustrated above would be some kind of spatial partitioning of volumes which you want to render together with a maximum operation combining shared overlaps.  If all you have is additive combinations you would see seams between your spatial partitions.

multiple_volumes_render_all.v2.hip

[dimovfx]

set all VDB names to "density" and set material1 node Attributes to "point attributes".

 

[fencer]

check the file

 

multiple_volumes_render_all.v2.hip