Hair Procedural random ID's

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Hi
I'm trying to assign random colours to the hair procedural, but not having much luck.
I've already randomized the id's at SOP level since I couldn't figure this out at shader level. no MtlX randomize?

What should I add in the PrimVarReader? "id" works on the guides render, but doesn't seem to on the procedural.
I did add "id" to the Attributes to Copy on the Hair procedural, but not sure how to access this from the shader?
Thanks
J

guides


render

Attachments:
guides.jpg (246.7 KB)
render.jpg (320.2 KB)

fx and lighting @ rebelway
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I don't believe there is one. The hair shader has a randomize function, but uses an internal id generator. ID on guides is useless since multiple guides are interpolated to each generated curve. The procedural sop network would be tasked with creating an id primvar at run time, but I don't think it does.
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O thanks man, pitty there isn't a option on the procedural, at least I wasn't missing something obvious..
Yeah I figured there would be some interpolation issues, and would end up in a sort of clumped look, but was curious to try.

Pity the hair shader doesn't have a bit more control for randomization, I'm using the Diffuse component, which doesn't randomize.

Guess one could always send off some RFE's
fx and lighting @ rebelway
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The procedural does output primvars:idon the Procedural Prim curves. I think the problem is the int to float connection, which for some reason isn't just auto-converted in every case? Also generating simple random numbers for Karma/MaterialX in-shader is more awkward than it should be, we're working on it.

Hope this helps in the meantime.

Attachments:
hair_proc_ids_material.jpg (58.6 KB)
hair_proc_ids.hip (363.4 KB)

I'm o.d.d.
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o wow, thanks for this Chris!
Yip agreed, simplifying creating random samples would be great!
fx and lighting @ rebelway
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try fabio https://www.sidefx.com/forum/topic/92598/ [www.sidefx.com]
it use the materialX ready for gpu and in the nodes randomize for the curves
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