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Git Commits -> Revision d5682b8

Revision d5682b8 by Lukas Toenne (compositor-2016)
June 8, 2016, 19:45 (GMT)
Fix cloth stability when in perfect rest shape.

The way cloth is coded, structural springs are only effective when stretched, while bending springs act only when shrunk. However, when cloth is exactly in its rest shape, neither have any effect, and effectively don't exist for the implicit solver.

This creates a stability problem in the initial frames of the simulation, especially considering that gravity seems to act so precisely that it doesn't disturb the strict equality of lengths, so in parts of the cloth this springless state can continue for quite a while.

Here is an example of things going haywire because of this and some suspicious logic in collision code acting together: {F314558}

Changing the condition so that structural springs are active even at exactly rest length fixes this test case. The use of >= is also supported by the original paper that the cloth implementation in blender is based on.

Reviewers: lukastoenne

Reviewed By: lukastoenne

Projects: #bf_blender

Differential Revision: https://developer.blender.org/D2028

Commit Details:

Full Hash: d5682b8bf64b35ad0042d7bcabe881aa8bd26f2d
Parent Commit: f1ec564
Committed By: Jeroen Bakker
Lines Changed: +5, -2

1 Modified Path:

/source/blender/physics/intern/implicit_blender.c (+5, -2) (Diff)
Tehnyt: Miika HämäläinenViimeksi päivitetty: 07.11.2014 14:18MiikaH:n Sivut a.k.a. MiikaHweb | 2003-2021