Open Shading Language

Hi all,

Is it possible to update OSL including all unsupported features like matrices and metadata.
It’s a serious omission that should be solved to make pattern generation more productive.

Looking forward to reply,
Thanks!

We’re open to contributions that improve the OSL integration, but it’s not a high priority for any of the active developers at the moment, as far as I’ve heard.

With OSL being CPU only it’s not used a lot by most Cycles users.

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With OSL being CPU only it’s not used a lot by most Cycles users.

Not by most, perhaps, but, perhaps, by some of the best?

Certainly, I am an OSL enthusiast, and I was wondering if there was some standardized way
of translating from the Blender Python API to the name parameter in getattribute() ?
The OSL manual mentions named per-vertex primitive variables;
in particular, I wish to read the vertex weight of the nearest (or, interpolated) vertex
according to some named vertex group:
would that qualify as a per-vertex primitive variable?

It’s not currently possible to access vertex groups from Cycles.

Only the ones mentioned in the documentation:
https://docs.blender.org/manual/en/dev/render/cycles/nodes/osl.html#attributes

Not possible at all? Not even through a driver expression?

No. You could convert them to vertex colors though.

Vertex colors; right: that’s what I did,
as explained here: https://blender.stackexchange.com/questions/118269/cycles-access-actual-length-of-hair-strand/118965#118965.

Last question: Currently the Hair Info node offers an Intercept,
which is the shading point’s position along the hair strand,
in a normalized way (always from 0 to 1).
Is there any way to access the hair strands’ actual length??

No, there is no feature like that.