Motion Transfer Tools
- retarget tool
- rig transfer, motion transfer
- animation transfer, animation copy
- fbx, dae, bvh
- Create a new Avastar Character (or use an existing one).
- Import your BVH animation file.
- Map the corresponding Bones.
- Transfer the Animation.
Loading an animation file
Blender supports the import of BVH files out of the Box. You find the importer in the Top menu at:
File -> Import -> Motion Capture
Note: You can set – but you do not strictly have to set – the Scale factor to match the imported Armature and the Avastar armature. However if you do not fix the scaling during import then you can easily end up in a situation like in the image above.
Quick fix for Scaling mismatch
This Match Scales function rescales the imported Animation rig to match the Avastar rig’s Skeleton. but note, we get the scaling value only from the Z-Axis and apply that value to the X- and Y- axes as well.
However, we have added a Map Guessing tool, which works nicely for Animations that already have been made for SL. You can just test the Guessing tool and see if your imported Animation rig is recognized. In the case above the guessing tool has identified the Animation Rig to be an SL/OpenSim compatible rig, thus all available Bones are automatically assigned and we do not need to bother with that.
The Bone picker lets you select one Source bones from the Animation rig and manually map it to a bone on the Target rig:
- Open the Animation source Rig in pose mode
- Select a bone
- Click on the corresponding assign icon in the map (see image)
Now the source bone is assigned to the corresponding target bone (In the example rThigh of the Animation Source is assigned to HipRight in the Avastar target)
The Range Mirror Copy lets you copy the limbs. Thus you only need to assign one half of the bones, then use this tool to automatic fill the symmetric bones on the other side.
- Assign one side of your animation source Rig to the corresponding bones in the Avastar rig
- Click on Mirror Copy to transfer the assignments to the other side of the Rigs.
The Clear Tool removes all associations in the Bone Map.
Note: The Reference Frame does not need to be part of the transferred set of timeframes. Actually in most cases the timeframe 0 is not used by the imported Animation. So it can be used to create a matching pose.
Create a reference Frame
- Set the timeline to timeframe 0 (or any timeframe which is convenient for you)
- Ensure the Avastar Rig is in Rest pose.
- Open the Source Animation rig in pose mode
- Select all Pose bones
- Reset Scale, Rotation and Transformation of the source rig (ALT +S, ALT +R, ALT +G)
- In the Viewport press “i” and select “Rotation”. This creates a new keyframe for the Rest Pose.
- Ensure the RefFrame in the Motion Transfer Panel is set to the timeframe where you just added the T-Pose (timeframe 0)
- Now you are prepared to Transfer single poses or the entire Motion (see below)
Note: Timeframe 0 contains the Reference pose, while timeframe 1 has been transferred from the imported animation to the Avastar timeline.
Make Seamless animations (experimental)
Simplify can be used to reduce the number of keyframes used in the imported Animation. We provide 3 options here:
- No Simplification (default)
- Lowes Global
- Lowes Local
These simplification methods are described nicely by Eyuphan Bulut in a scientific paper about Keyframe extraction from Motion data