externalize the script and other fixes

[geowarin]

I thought I would be easier to contribute to the repo if the python script was in its own file rather than embedded in the blend file.

This way, we can work on it concurrently, merge it, see its history, etc.

Other fixes:

• fix vertex explosion by resetting the armature between fbx imports
• apply LOCAL constraint to fix wrong hips relative bone position
• apply an offset position to the root bone constraint to try to correct the position (kinda works)
• change the animation crawling algorithm to be more granular

To be honest I don't know if this will work better in all cases or not.

[geowarin]

Some animations are wrong in LOCAL space:

shoulder position is incorrect

Honestly, I'm discouraged. It feels wrong to work so much to fix something I paid for.

[cdoise-vbg]

I seem to recall the shoulder twisted around issue went away if I edited the target armature on PolygonSyntyCharacter to have the right clavicle connected to the upper arm bone and rolled it so X/Z axes matched other ones on the arm, but it's been a while since I originally tried that character, so I'd probably have to go back to confirm that's all I did other than disconnect hip bone from root bone (but that was when I still had issue with the third finger on left hand).

[geowarin]

@cdoise-vbg thanks for the reply!

For reference, on which model did you have the most success with the re-targeting? Was it a synty character? Since I'm only interested in the animation library, any known good model would do.

other than disconnect hip bone from root bone

Wouldn't that prevent from using the root motion animations? I would be happy with only the non-root animations working if they can reliably be retargeted.

[cdoise-vbg]

PolygonSyntyCharacter from the Synty animation packages was the one I had the best results with, after making the aforementioned changes to hip bone and right clavicle. For hip, I said "keep offset" after disconnecting. It appeared to be working with root motion when I looked at the animation in playback, but now that you mention it, that might just be because it was copying the global transform...

I'm afraid I'm thinking of pausing my efforts on this particular sample for the time being. I need to go back and spend some time on the basics of Blender add-ons and animations.