4.3.35-beta: Additive damping gives bones seizures

Paperbot

Damping keys in any additive animations will make physics for the bone freak out.
.Keyed values don't seem to matter
.The longer the animation is active the longer it'll take to return to normal after being deactivated (damping feedback loop, going into negatives perhaps?)

To reproduce:
-Open Spineboy
-Give physics to the gun
-Set an animation with a damping key for the gun's physics (it doesn't matter if it's 0, setup, or any number)
-Play test animation as additive on playback

(ignore the animation name, it's not inertia)

Misaki

Paperbot I tried the steps you provided, but the problem did not occur when a damping key was present in the animation played on the lower track. Therefore, I believe the following rule applies:

add is intended for animations layered on top of others, not for the first animations applied. Properties set by additive animations must be set manually or by another animation before applying the additive animations, else the property values will increase each time the additive animations are applied.

https://esotericsoftware.com/spine-api-reference#MixBlend-add

In the video you showed us, we couldn't see how the damping keys were actually set, so if the animation playing in the lower track has a damping key and the problem still occurs, we would appreciate it if you could provide us with a Spine project that reproduces the problem.

Paperbot

Misaki

How the keys are set doesn't matter.

spineboy-dampingbug.spine

59kB

Physics on the gun was left as default (15 damping)
TEST has a single 15 damping key (as additive should be +15 over base 15 = 30)
TEST_0DAMPING has 0 damping (as additive should be +0 over base 15 = no change)

Both cause the gun to spin out of control
Loop and mix do not matter either

Misaki

Paperbot Thank you for clarifying! I have confirmed the conditions required to reproduce this issue and have created the following issue ticket: EsotericSoftware/spine-editor900
We apologize for the inconvenience, but please wait until we have resolved this issue.