I’m rigging a digitigrade foot (not something I do often I admit).
I’m having a recurring problem with flipped axes in pose space. All my bones in ‘edit’ mode show the ‘local’
X-axes correctly aligned along +X in blender space.
But in pose space, a few ‘toe’ bones have the X-axis flipped to point -X.
This is causing issues with a copy-rotation constraint I need to use (as I also need to use ‘offset’ there, so can’t
invert as ‘offset’ doesn’t also invert).
Here’s a composite pic’ (3 screen grabs) showing the issue.
As I say, in edit mode all bones show the correct orientation in local space. Does anyone know what’s causing
this or how I fix it?
I’ve tried messing around adding new bones under the same parent, and at least once saw an added bone
with the correct pose-space axes, but I was never able to reproduce whatever I did to get that. Most
bones added appear to be incorrect, but I hate the fact that it seems to be unpredictable.
Best to enable Axes via Properties > Armature > Display > Axes.
The bone roll in edit mode controls hows the axes are align in pose mode.
In edit mode you can press Ctrl+N to align bones to the different axes, or just set manually in the Transform panel.
Thanks for the axes trick dirty-stick. It helps to see the problem.
Ctrl-N (I think) aligns roll to global Z which is already the case, so has no effect.
I ‘can’ flip X using a manual roll setting, which is inaccurate, and of course ends up with ‘Z’ flipped.
But it leaves X correct, and it does solve my copy-rotation problem.
I just wish I knew why blender was flipping X. Sure looks like a bug to me.
[Edit: Doh! Now matter how you fix it, local Z will end up pointing down. Brain clearly
not in clear. Hmm. Maybe the code is simply trying to keep ‘Z’ up?]
Uhm, I see what you mean.
I know there is a common problem will bone roll, this may be related.
Though you would probably have to talk to a dev to be sure, mont29 usually deals with these issues.
I dont know much about this specific problem.
