Godot - Mirror Animations

This module adds a "Mirror" option to animations imported via FBX / GLTF etc.
It only works for humanoid rigs and only if the armatures rest pose is in a proper T-Pose.

It's not tested with other poses, however, not having a proper rest pose will break the animation.
This module was written for Godot v4.2+ and might not compile for version lower than that.

Setup

1. Clone the godot engine somewhere to your local machine
2. Follow the Building from source guidelines here
3. Add this repo as a submodule to your project:
   cd /path/to/godot/ git submodule add -b main https://github.com/Lunatix89/godot-mirror-animations modules/mirror_animations
4. Rebuild the engine

Guidelines for typical unity animations

Unity animations are typically split up in a character in T-Pose and several, small animation files which won't contain a skin, just the armature with the specific animation.
There are also animations out there which don't have a proper T-Pose set for the individual animation, the rest pose is just the first animation frame.

To work around this:

1. Buy and install Better FBX Importer & Exporter from blender market.
   This plugin will solve wrong bone orientations which can occur with the default FBX import plugin as well as having a special import option which we later need.
2. Import the actual character which should has it's rest pose set to T-Pose. Make sure that it has a proper armature and rest pose set up.
3. Select the armature
4. Import the desired animation with Animations Options / Attach to Selected Armature checked. If the animation files also import an armature and model, select and delete them
5. Export as glTF 2.0 - this is important, do not export to FBX again
6. Import into Godot
7. Open the advanced import options dialog
8. Select the desired animation
9. Check Mirror on the animation
10. Click Reimport

Please note that I can't guarantee that this will work for every animation file as I only have a limited amount of files to test with.