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How could I take a Rigid Body simulation (it doesn't matter if it is already baked or not) and reverse it before rendering.

I do not mean reversing the clip after it is rendered (mentioned here).
I want accurate motion blur, because I am running another physics simulation at the same time that I want running "forward".

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  • $\begingroup$ Hi, so, actually your question is a bit confusing, so could please add a few more details for more clarity? $\endgroup$
    – Aster17
    Apr 3 '21 at 3:00
  • $\begingroup$ @Aster17 What do you have trouble understanding about it? I am trying to bake a physics simulation and then have it play backwards, or just bake it backwards. I do not want to render the clip without the reverse and then use the blender video editor and reverse it. $\endgroup$
    – b blox
    Apr 3 '21 at 3:16
  • $\begingroup$ blender.stackexchange.com/questions/95633/…. would this help? $\endgroup$
    – object
    Apr 3 '21 at 3:55
  • $\begingroup$ @bblox have you tried something like setting the start time as the end time and the end time as the start time. Something like start time 250 and end time 1? $\endgroup$
    – Aster17
    Apr 3 '21 at 4:41
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Option 1

For Rigid Body sim you can try ... Bake simulation and with object selected search for Bake Action > enable Visual Keying ... it converts cache into keyframed animation.

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Now if yo go to Graph editor and move timeline into a middle frame of your anim, you can Mirror curves Ctrl+M Over Current Frame ... results as reverted animation.

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Option 2

Another option can be Export as Alembic (.abc) and Import back ... under Constraints Properties you can animate Override frame value backwards - at frame 1 set value of end frame and on last frame keyframe value of 1 ...

enter image description here Mentioned here

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Using Blender 3.0, in order to reverse the physics animation I had to do this :

  • Like Option 1 of the above vklidu's answer : with object selected > Layout (in object mode) > Object > Animation > Bake Action (with Enable Visual Keying)
  • Open Dope sheet mode
  • Select the object new baked keyframes you want to reverse (the selected keyframes color turn from white to orange)
  • Right click > Copy or Ctrl + C
  • Move the timeline frame cursor to the frame you want then Right click + paste or Ctrl + V
  • The new pasted keyframes should appeared, and they are now the selected (orange) ones > Move the timeline frame cursor in the middle of your selected new keyframes
  • Ctrl + M (Opens a dialog entitled Mirror keys) > By times over current frame
  • IMPORTANT last but not least : In the physics properties of your object > Rigid body > Settings > check Animated (because if not: you might never see the result of it all !) ... You can also only make it animated only for this part by "keyframing" this checkbox as it is possible.

Hope it'll help :)

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