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Wire solver, selfcollision and sdf?


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Has anyone noticed anything strange with the wire solver and self collisions? It doesnt seem to work that well when the collision method is set to sdf. I havent tested that much yet as I just noticed it, but with Global Geometric it seems to work pretty much as you would expect - but that is awfully slow.. Local geometric seems quite fishy as well.

Is there anything you can do to improve this while still using sdf collision?

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Yeah noticed that with SDF collision, however it still produced a consistent transition between frames. More of  resolve passes make it more accurate. Here's how one my test looks. By the way, part close to hair roots does not belongs to collision, it's just a very strong 'target stiffness', gradually faded along curves. For my taste, main problem with H wire solver, I don't know how to avoid effectively, is not natural springy movement.


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Thank you, so it's not just me going crazy  :P


I ran some tests over night and both Local/Global geometric is out of the question. It's just too slow and unstable, even though you get nice selfcollisions with Global. SDF is really the way to go, both for speed and that it's stable.


I did fiddle with the Resolve passes before, mainly to get a faster solve. But yeah I suppose I can't go too low, I have to experiment a bit together with substeps. 


Also, how much width do you have for your curves? The groom I got is sitting pretty tight so my width needs to be quite low; but I lose a lot of volume since they are very thin and not colliding properly. I would like to make them thicker, but it's a reeeeaally long shot so if they are too thick (and interpenetrating at the start), they get all tangled up roughly half way through and it just becomes a mess. 


Yeah anyway, thanks for your input! I'll keep trying, any tips are welcome  :)

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For this one I raised up the diameter (width * 2) to equivalent of 2 - 3 cm, just to show effect. Worked before with half of that value. For keeping the layered groom only by collisions, I'm not optimist, even with much more than around 220 guides like there. I think this have a chance to to work believably, starting with thousands of guides or more. So, used a strong Target stiffness just to fix the part around roots. Also used a blend with plain animated deformation, after DOP import, to fix the spring movement. This and this is how final looks like.

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