I have noticed that importing animations from my .blend file results in all bones receiving at least a start and final keyframe in all animations. This means that I can’t use layer-based blending with AddMixingTransform because all animations have keyframes defined, I have to use additive blending.
I made a copy of the animation that was being problematic, in Unity, and removed the keyframes manually with the Animation Editor window and the animations layered properly. Has anyone found a solution for this? Some import/export settings I am missing?
Thanks for the help, let me know if anything needs clarifying.
Adding a picture to help explain the problem.
Depicted is one of the animation clips that has been imported. Many of the bones have only two keyframes, one at the start and one at the end of the animation. The resultant curves are flat bone local positions/rotations/scale curves. These are not present in my blender animation, the bones are unkeyed there.
What this ends up doing is defining all bones for each animation, so I can’t use the layer “fallthrough” aspect of blending animations. I can use additive blending, but not weight blending, since all bones receive the weight of the animation clip rather than only the defined bones in the clip.
Found a thread which seems to talk about this problem, but the solution is 4 years out of date, and doesn’t easily apply to the new export_fbx.py file with Blender 2.7. At least, I don’t know how to implement it in this new context.
An update admitting defeat:
I did some more research and tracked down a Blender Developer a lot more knowledgeable than me about this process. Ultimately, he told me that its not really possible if you’re using IK. The IK propogate to other bones, which can themselves be under the effects of IK, and propogate further, etc, to the point where you have to distinguish between tiny floating point values and zero to know if the bone is being animated in an action or not.
He mentioned other constraints in the form of additional ways for a bone to be indirectly animated (drivers, unusual parenting with hinges, “etc”), which I did not understand but figured was worth mentioning.
So what are my options? I can duplicate an animation and remove the bones I don’t think are animated in a given animation, and set up a Unity AssetPostProcessor which copies my imported animations to the target duplicate, inheriting the same bone rejection as before, or I can forfeit animation blending and depend on additive blending instead. For now, I think I will go with the latter, though I’m not happy about it.
I know this is pretty old thread but I stumbled upon this problem myself and I have found the solution.
I am not sure whether such option was available in Blender 2.7 but in Blender 2.78a which I am using, in the FBX export under “Animation” there are two check boxes you want to uncheck - “Key All Bones” and “Force Start/End Keying” - reason this fixes the problem is pretty self explanatory.
However this dialog does not come up if you simply drag and drop the .blend file into unity. So you have to manually export it to FBX.
