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bbone flips when crossing Bone Z axis
Closed, ArchivedPublicTO DO


When rotating bbones over the bonespace Z axis, the bbone experiences a twist-flip.
Since BBones are bezier curves, this corresponds to the old 'Z-up' method of twist. However, Blender has better ways of handling bezier twists, so it would be nice to get these working for BBones.

Attached is a .blend file with two armatures. in the selected armature, when you scrub the animation, you'll see a nasty twist in one of the bbones; in the other armature it doesn't twist even though the visual rotation looks the same; this is because the bone rolls in the two chains are 90 degrees off, so that one armature crosses Z (the one that flips) and the other crosses X (and doesn't flip)

OS GNU/Linux 64 bit, Intel.. but I suspect this is not architecture dependent.

Event Timeline

I copied the report to the wiki todo, it's a nice project for new devs or when maintenance is being done on Armatures in general.
Thanks for report, but closed as todo item...

Ton Roosendaal (ton) changed the task status from Unknown Status to Unknown Status.Feb 16 2011, 2:42 PM