sampling animation should keep bones without animation, blank

[stann-co]

Is your feature request related to a problem? Please describe.
I have a situation where im trying to export a character with animations. I only want the deform bones exported, and i also do not want there to be keyframes on non-animated bones

I cannot export deform bones only, without sampling animation enabled, and sampling animation causes keyframes to be added to every single bone.

Describe the solution you'd like
Either sampling animation should preserve empty animations, or there should be an option to get rid of those extra blank keyframes that's added

Describe alternatives you've considered
I can try and figure out a masking solution inside my game engine.
Or i need to split up my rig into animation and game rig, and export to it, everytime i make changes, before exporting as glTF

Additional context
Here 2 animations are blended together.

one of just the hatch opening/closing
and the other of the mech crouching (no keyframes on the hatch)
because sample animation, adds keyframes to every bone. The hatch animation gets cancelled out when blended

[julienduroure]

Hello,

Did you try to uncheck the "Force Keeping Channels for Bone" option?

[stann-co]

Hello,

Did you try to uncheck the "Force Keeping Channels for Bone" option?

I just double checked and it seems to act a little odd.

With Force Keeping Channels for bones, checked on.
Keyframes are added on every single bone.

With it off,
actions that actually had a single keyframe on all bones, to do a specific pose, are gone.
In my case the chest bone only does keep it's keyframe though for whatever reason

(i also tried to uncheck optimize animation, but it seems to be the same result)

[julienduroure]

Hello,
Can you please provide your .blend file?

[stann-co]

https://drive.google.com/file/d/1S5AdI7XGocJo_C67g8BhwU17SW1Xane3/view?usp=sharing
yes here you go, for extra info, this is a rig made with cloudrig, and there's a collection of deform bones driven by the rig, those are the only ones i want exported.

The relevant collection to export is "mech"

[stann-co]

let me know if there is anything i have missed, or stuff i can help with

[MoritzKoehlerDesign]

Hi I have the same or similar issue, I dlike to have same keyframes as blank. To share an animation with different Characters the location keys (expect hip or roots) have to be blank but i cant figure out how to make an empty animation without going trough all the channels. my workaround is to use c4d glb export which kompletly deletes similar keyframes.

[stann-co]

I am guessing the difficult part, is to preserve bones animated with drivers, and that's why every bone gets sampled.
And also in my case i have deform bones driven by an animation rig. So maybe the best way is to check after the sample if there's any bones with only a single keyframe with default rotation/position/scale, and if so delete it.
Just an idea!

I attempted to look through code if i could figure it out myself but it's pretty big, (and i couldn't figure out right now how to run my own fork of it)