Are all subsurface material in Karma unsupported now?

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https://www.sidefx.com/faq/karma/ [www.sidefx.com]
So we can see that the table shows that physical subsurface scattering is supported in Karma CPU
But when I test it the physical subsurface scattering material appears black. (The materialX default subsurface appears correct)
Also random walk subsurface cannot function as well.

When can we expect to have sss supported in Karma?
Or is there an SSS material for skin/jade/liquid that can be used in Karma CPU and Karma XPU currently? Also things like hair also currently only works in CPU mode, not in XPU mode
Edited by goose7 - May 14, 2022 07:20:32
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https://www.sidefx.com/faq/karma/ [www.sidefx.com]
So we can see that the table shows that physical subsurface scattering is supported in Karma CPU
But when I test it the physical subsurface scattering material appears black. (The materialX default subsurface appears correct)
Also random walk subsurface cannot function as well.

When can we expect to have sss supported in Karma?
Or is there an SSS material for skin/jade/liquid that can be used in Karma CPU and Karma XPU currently? Also things like hair also currently only works in CPU mode, not in XPU mode

There's three subsurface models that are supported in Karma, the old one from mantra the "PBR SSS" VOP, sometimes know as diffusion, and the new randomwalk subsurface shader "PBR Random Walk SSS". The third one is just a single scatter "PBR Single Scatter". The 'physical sss' you mention is a very very old mantra shader and its not supported in karma. For some reason the only working subsurface node that isn't hidden is the PBR SSS one. You'll have to dig inside a principled shader and steal the vop for the other two or use python to create the node.
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> Or is there an SSS material for skin/jade/liquid that can be used in Karma CPU and Karma XPU currently?

MaterialX SSS will be working for XPU (matching with KarmaCPU) in the next release of Houdini

> Also things like hair also currently only works in CPU mode, not in XPU mode

KmaHair should give identical results in both KarmaCPU + KarmaXPU right now in 19.0
(see attached .hip file)

Attachments:
curve_test_v25.hip (256.4 KB)

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