Adventures in Animation Retargeting
Retargeting notes:
Today I attempted to retarget animations from the Shinabro Platformer set onto the Casual RPG Character Anna skeleton/rig.
I attempted to import the humanoid rig Anna .fbx file, but there was an error in Blender and the rig was imported but had no 'weights' to the mesh (so the bones would move but the character would not). I found out that this is more-or-less a known bug which is open for Blender but hasn't been resolved yet. I bought a plugin off of Blender Market called "Better Fbx Importer & Exporter" which allegedly solves problems like these where .fbx files work in other programs but not in Blender.
After installing the plugin, I imported the Anna humanoid .fbx and then one of the Shinabro Platformer animation .fbx files.
I opened Auto Rig Pro > Remap, selected the Shinabro rig as the source armature and the Anna rig as the target armature.
I built the bone list, and clicked Auto Scale to shrink the Shinabro rig to the approximate size of the Anna rig.
I noticed that the Shinabro animation did not come with a proper 'rest pose', so in order to fix that I clicked the
Redefine Rest Pose button, highlighted all of the source armature bones, and then hit Copy Selected Bones Rotation
which caused the Shinabro animation to have a T-pose rest pose.
Once that was complete, I was able to do the bones mapping. The naming of the bones for each rig was nearly identical,
so ARP chose the matching bones for all of them correctly. I clicked on the Bip 001 bone and marked it as "root",
and then hit "Retarget" and it kind of worked!
One issue with the retargeted animation was that Anna's feet are arched in a strange way and are floating off the ground. Not only that, but as the character breathes, she appears to levitate up and down. I tried to fix this by enabling IK for the Anna rig and that did cause her feet to stop moving, but it also stretched them out all the way to where the original rig's feet were located (which didn't look correct.)