UsdPreviewSurface materials not displaying in usdview with Storm renderer (Hydra 2.0)

[hamedsabri]

Hi,

I’m running into an issue where UsdPreviewSurface materials are not displaying in usdview using the Storm renderer (Hydra 2.0) in OpenUSD 26.0
despite explicitly applying MaterialBindingAPI and authoring valid material bindings.

Please see attached Donald_Duck_FixedSchemas.zip

Specs:

OS: Windows
OpenUSD 26.03 + Storm Render delegate

[jesschimein]

Filed as internal issue #USD-11923

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[blevin]

Hello @hamedsabri , thank you for the attached file. I took a look and was able to determine the issue: currently the material bindings are for the "full" purpose, for example on line 196:

rel material:binding:full = </scene/Materials/blanc>

Storm, as a "preview" or interactive renderer in USD terms, will only use the empty "all purpose" or "preview" bindings.
If we change this bindings like so, it will work in Storm:

rel material:binding = </scene/Materials/blanc>

I have asked the USD team if we have any documentation we can point towards that further explains this concept, since I know it has confused several of us before.

[blevin]

There is some more discussion here - hopefully this helps:

https://openusd.org/release/user_guides/render_user_guide.html#using-material-binding-purpose

[hamedsabri]

Hi @blevin,

Thank you for looking into this and the link is helpful.

However, I tried switching the binding to implicit "material:binding" and still I don't see the material showing up in storm.

Donald_Duck.zip