How to convert a cloth simulation animation to keyframes

Support Particles and Physics Simulations
1

Hi All,

I desperately need to convert a cloth simulation animation i did for a short video* into keyframes, so that i can get it to work in unity for the AR work i do.

Is this possible? If so, please help me

*(the video is of letters and paper and magazines falling onto a doormat and for three of the magazines i used cloth sim to animate it to make it more realistic)

Thanks in advance

1 Like
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This will convert a cloth sim into keyframes. I recommend saving a new version to try this on.

  1. Make sure your scale, location and rotation are applied on the cloth object. (ctrl-A)
  2. In user pref, add-ons, type ‘light’ and enable ‘import:export Lightwave Objects’ (check the checkbox)
  3. Then type ‘new’ and enable ‘import:export NewTek mdd format’
  4. Save your prefs.
  5. With your cloth object selected, choose File-Export-‘Lightwave point cache (mdd)’ Give it a filename (same as the blend is good)
  6. Delete the cloth sim on you cloth object, in physics.
  7. With the cloth object still selected, choose File-Import-'Lightwave point cache (mdd) . Choose the .mdd file you saved.
  8. The cloth is now keyframed, with a shapekey on every single frame. Sometimes you need to scrub the timeline to refresh the initial loading of the keys in the viewport, but it’s there. I have no idea if this will work in the game engine however.

mdd.jpg804×641 175 KB

5 Likes
3

Thank you very much blenderallday

At first i followed your instructions and i couldnt figure out why it didnt work, my animation was going crazy messing up, however, after a few tests i realised it was because i had to first apply the subsurf modifier i had above the cloth one and then do your process again and it worked- hurray!

Thanks again,

GirlRacer64

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blenderallday, i dont suppose you know if it is possible to make those shapekeys into just keyframe animation without shapekeys?

I cannot use shapekey animation for the fbx export i have to do to get it into junaio

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The thing with a cloth sim is that the mesh will deform and those deformations must be accounted for somehow. The steps I outlined rely almost entirely on shapekeys and I can’t see a way around them. As I mentioned I have never continued down the export workflow you are doing and I really don’t know.

Perhaps you could put a simple 3 or 4 bone armature on the magazine and use the cloth sim as a side by side to recreate the look and timing of it falling.

Or do the same with a lattice?

You might want to start a new thread in rigging/animation and outline your goal. There is always a way. I’m just not sure what that way is here. :no: (Edit: just saw that you did)

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ok yeah will try that if i get the time,

Thank you very much for all your help

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This should by now be a standard feature built into Blender. Or at least an add-on. In complex scenes its brilliant to be able to create things like simulations in new blend files and bring them into the main scene as keyframed shape key sequences.