Thanks again for the file.
I guess I tell you now all that you are already aware of. So bear with me.
Character joint animation is based (except for toon-like stretched arms or legs, etc. Animation of PS will change the target!) on rotation only. Even keyframes on Position should be avoided to prevent trouble. One can’t really rotate a joint above another that has position keyframes, and expect that position animation is kept The parent will be the child’s “world” axis!). The motion retargeting takes the rotation and transfers it to the next.
Not positions! Otherwise, your newly animated character would grow and/or shrink.
Some explorations (Source Rotation, Rot+Pos, Rot+Scale)
In the is way, if one character has longer arms than the source, but perhaps not equally longer spline joints, the rotation will end up with penetration, or distance where no distance was before.
The woman’s foot is set up for high heel shoes, the toes have a different angle than the source based on that. The rigs have each a reference pose. If there is a delta (difference), then that difference will be acknowledged in the transfer, of course. Otherwise, the toes would point in an unwanted direction. Your movie clip shows the foot joint angle-relation very well.
Now you might say that should be all handled by the Character Definition/Motion Solver tags. How would that work, considering the character had a motion on its own, and get from several different sources motion before and after that? Shrinking arms, stretching legs, and adjusting spines each time differently? But that would be required.
How about flat shoes v. high heel shoes? (Rhetorical questions…). Even if it would be possible, perhaps I’m not aware of it, how much of the physical expression might get lost or exaggerated? We use characters to express with body language and actions as much and as precisely as possible. As the first lecture in filmmaking goes: Show – don’t tell. Which sets us some limitations to allow automated processes to take over. Perhaps Ai will do more in the future.
Again, I believe I have told you nothing new, only put into the Character Definition and the Motion Solver context.
If you think there is a problem, please always feel free to get input from the support.
However, I’m happy to look into anything that comes up.
My best wishes