Atomic Perception

I have not tried it in Houdini 17, but in previous versions, the .OBJ export did not support that. There is a script that leverages the Post-Write event field of the export ROP. Place the code in the script field, change the code type to Python and when the export is issued, the code will re-write the resulting .OBJ file to produce a new .OBJ file with material assignments for detected groups. These materials are generally what importers look for.

https://forums.odforce.net/topic/25214-post-processing-an-export/?do=findComment&comment=146948 [forums.odforce.net]

Thanks for the explanation and the working file. Deform Guides seems to do the trick.

In this HIP file, the hair strands acquire their color from the texture map of the source via vex xyzdist function.

Confirmed, vellum hair does not work correctly with deforming geometry that contains the same point count. That is odd, because that is the most typical use case. If I translate a static object, it seems to work as expected.