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Vellum orient

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NAHASSIA
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Hi

Is tehre a way to keep initial orient on "attach to geomeetry" vellum cloth point. It seems that its only transform constraint and no rotation constraint. I would like it to behave the same way as vellum hair "pin to target" points.

in the mp4:
in blue cloth with attach to geo
in orange hair with pin tot target

stretch stiffness and bend stiffness are the same on both.

Or maybe a workaround?

THX
Edited by NAHASSIA - March 20, 2023 15:27:15

Attachments:
vellum_orient.mp4 (43.0 KB)
orient_vellum.hiplc (495.5 KB)

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Enivob
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You can dial in some of that by distributing mass across the gradient of the mesh. Calculate a 0-1 index from the relative bounding box of the source, in this case the x-axis. Use that index to drive a ramp where you can remap and rescale the final value. The net result is a little bit of falloff, and not a complete collapse.

Attachments:
cloth_like_hair.gif (666.5 KB)
ap_orient_vellum.hiplc (504.5 KB)

Using Houdini Indie 20.5
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NAHASSIA
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Very nice Enivob THX
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tamte
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only Hair can have true orient related constraint, even though you are not taking advantage of that in your file as you are pinning 2 root points instead of 1

however to get your left side working the way you may expect with 2 segments attached
- turn on Tangent Stiffness on /obj/VELL/vellumattach1
- increase your Bend Stiffness on /obj/VELL/vellumcloth1 to something like 1x10 or more
(or to 1x0.01 but also increase solver Substeps to 3)
Edited by tamte - March 20, 2023 18:17:11
Tomas Slancik
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NAHASSIA
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THX alot tamte I will try it.
Cheers
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