Uprez SOP Volume

[jacob clark]

Hi Guys,

I am trying to uprez some volumes in the SOP Context.

These have are low rez volumes that have been run through DOPs, and would be great to uprez them and pipe through the Volume VOP.

Is there a SOP to do this?

cheers,

-j

[Allegro]

Off hand, I don't know of a way; I'd be tempted to scatter points in the volume, transfer any attributes, and use those points to generate new volumes of whatever resolution you want.

[johner]

If I'm understanding what you want to do, couldn't you use a higher res IsoOffset node with Mode set to "VolumeSample"? (Although testing this, it seems like there's a weird bug where the OutputType set to SDF in that mode yields a Fog Volume and vice versa.)

Or use a Volume SOP to create a volume of the same bounding box size, then a Volume VOP that just VolumeSamples the original lores volume? It's all just going to be doing linear interpolation of the lowres volumes, but I think that's the best you're going to get easily.

See attached.

Edit: yeesh, just realized this gets more complicated with multiple volume primitives, which is what you're probably dealing with from DOPs. But you should be able to put the same setup through a ForEach SOP to sample them individually.

Edit: see attached for an example of one way of using ForEach to handle mutiple volume primitives.

The volumes in the incoming gdp are all sampled and the sum of their values used to initialize the signed distance field. No correction is done after the fact, so the result may not actually be a signed distance field if the input isn’t.

upres_volume_sop.hip

upres_volume_foreach.hip

Edited September 2, 2009 by johner

[jacob clark]

Hi Johner,

I hadn't thought of the Volume Sample with the Volume VOP.

That looks like a good idea with the current toolset!

cheers,

-j