Additive clips are strange

Unity Engine
1

I tried creating a simple additive animation clip using the animation editor. I keyed a blend shape to 50 at 0 seconds, 0 at 1 second, and back to 50 at 2 seconds. When I play it in the animation editor, it does what you’d expect.

However, when I play it in scene, it seems to zero out the first frame: instead of going from 50 to 0 to 50, it goes 0 to -50 to 0.

That doesn’t make sense. If I wanted the clip to subtract 50, I’d have keyed -50.

The only workaround I’ve found is to create a second dummy animation clip, key everything to 0 in it, then set this as the additive reference pose. (Which I can only seem to do by switching the inspector to debug–this stuff seems to only be exposed in the animation import inspector, and this isn’t an imported animation.) Is that really necessary just to get additive animation to actually simply add what I tell it to add?

2

Sounds like you need to acquire the additive reference pose on blend shape at 50.
See Additive Reference Pose - Unity Engine - Unity Discussions

3

Like I said, I created a reference pose (at a value of 0, not 50)–but the only way to do that was to create a separate dummy clip, and it required going into the debug inspector to even see the property. The whole thing is very strange.