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+--- Thread: Rope twist at attachment point (/thread-3176.html)
Rope twist at attachment point - burspa - 15-11-2021
Hi
Is it possible to stop a rope from twisting at its attachment point? Using Rope extruded Renderer.
I would like the end control points to be clamped in place with no rotation.
Perhaps I'm doing something wrong?
Cheers!
RE: Rope twist at attachment point - josemendez - 15-11-2021
(15-11-2021, 01:49 AM)burspa Wrote: Hi
Is it possible to stop a rope from twisting at its attachment point? Using Rope extruded Renderer.
I would like the end control points to be clamped in place with no rotation.
Perhaps I'm doing something wrong?
Cheers!
Ropes do not model twist/torsion, as explained in the manual:
http://obi.virtualmethodstudio.com/manual/6.2/ropesetup.html
If you mean bending, using ropes you can just attach two control points that are very close to each other. This works because a single point in space does not determine a direction, however two points do.
RE: Rope twist at attachment point - josemendez - 16-11-2021
(15-11-2021, 10:04 PM)burspa Wrote: Oh thank you! I was meaning there's like UV offsetting on the renderer.
This "offsetting" is just the rope rotating around its longitudinal axis. This kind of rotation is called "torsion", and ropes do not explicitly model it: they're free to rotate around this axis.
Rods on the other hand use a much more accurate model that considers coupled torsion, bending, stretching and shearing (compared to rope's bending and stretching only), allowing them to reproduce a range of complex behavior that ropes cannot (plectoneme, coiling, etc).
(15-11-2021, 10:04 PM)burspa Wrote: The issue with going mesh or rod is that I still need to slice it. But I could get a mesh slicer I guess if there's no simple solution
Ropes can be torn/resized, but can't model torsion. Rods can model torsion, but cannot get torn or resize (see the comparison chart here: http://obi.virtualmethodstudio.com/manual/6.2/ropesetup.html)
So if you need both you're out of luck
. You'll need to bake the rod's mesh and then slice it using some other means.