rendering SDF as fog

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is there a mantra property or something that allows rendering SDF (VDB or native) directly as a fog volume?
Essentially something like uniform volume, but non-uniform and from SDF
Tomas Slancik
FX Supervisor
Method Studios, NY
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hi tamte. i don't know about a mantra property for this, but thresholding the surface field in the shader and rendering that as density works to do what you are describing.

here's an example:

Image Not Found
Edited by brianBurke - Dec. 3, 2018 22:20:56

Attachments:
bb_sdf_as_fog.hiplc (320.9 KB)

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thanks Brian, this would work for dense volumes and is kind of the approach I have as a back up (density < 0)
however I'm hoping for some property so that hopefully
- all inside of SDF VDBs will be shaded as fog without the need to use Fill Volume to get the values deep inside
- native Volumes would get optimized in far positive values when building the octree, currently the full box has to be raymarched
Tomas Slancik
FX Supervisor
Method Studios, NY
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