RBD Procedural Motion Blur

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I've set up a super simple rbd procedural with Point Location parm set to "File Cache". I'm trying to get geo motion blur working and attempted to use a lop cache. However, it's returning a lot of warnings complaining about varying attributes. Is it possible to get non-velocity based motion blur with the rbd procedural?
Edited by jarjarshaq - Feb. 19, 2025 14:37:26

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setup.jpg (10.4 KB)
warnings.jpg (26.1 KB)

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I have also attempted to read the points from the sop by setting the Point Location to "Primitive" as outlined in the help doc:
https://www.sidefx.com/docs/houdini/solaris/houdini_rbd_procedural.html#solaris-setups. [www.sidefx.com] However, no luck getting geometry blur to work.
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Houdini Procedurals do not currently support geometry blur, only velocity blur.

The RBD Procedural's "preview procedural" toggle previews the result in the viewport - it does this by writing the result of the procedural directly to the affected prims' various attributes. This only happens when viewing interactively and is disabled when writing to disk, leaving the procedural execution to husk, at render time.

Adding a cache LOP after the procedural is therefore misleading and results in the warnings you see since the procedural preview just writes values as default values, not timesamples.
If it was to write timesamples that you could cache, it'd defeat the purpouse of using a procedural in the first place since it'd bloat your usd cache with deforming point positions, normals etc, effectively "baking in" the results of the procedural.
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Thank you for the clarification. I have opted to go with the transform by points lop and a cache node. In this particular instance you can really detect a lack of rotational transformation on the rbd pieces. I hope geometry blur is something SideFX is exploring.
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