"pre"overshoot elastic interpolation

[Nicohk92]

Hey guys, let me open by pointing out that the way elastic and bounce interpolations work are a bit counterintuitive (at least to me). It seems to operate on the keyframe AFTER the one it is applied to.
Whether I need an overshoot or a bounce, my natural instinct is that it happens at the destination keyframe, and should be applied there, not before. But anyway..

I don't know if the title is explicit but basically I need to create a sort of reverse overshoot, meaning giving a bit of elasticity to the very start of a movement from its static pose. It needs to go quickly the opposite way slightly before making its normal trajectory, in order to get that dynamic cartoony feel.

I can't seem to be able to do that with the elastic interpolation, cause as stated before, it needs to be applied to a previous keyframe for some reason, and that previous keyframe doesn't exist in my case since it's the beginning of the move.

Am I missing something here?

Thanks in advance

[synthsin75]

All keyframes interpolate from that key forward, otherwise, a future key is effecting the past timeline. In the case of elastic, bounce, etc., the interpolation of one keyframe ends at the next keyframe. It doesn't actually effect the next keyframe.

Elastic just isn't meant to work in reverse, as it simulates real world motion. You'll likely need to keyframe that motion manually.

Or you could export the animation, import it, and play it backwards.

[Nicohk92]

Your explanation makes sense.

And it did help me find the solution, for anyone looking. Elastic does work in reverse. SImply tick the "backward" checkbox.

[synthsin75]

Nice, I forgot about that option.