I had an interesting issue today with rendering cloth simulations with Movie Render Queue in Unreal Engine: my cloth was either not showing up at all, or it was royally freaking out, as illustrated in the above screenshot. I spent two whole days testing and researching, until I found the issue my animations were having: it was the start position of my characters.
Usually when I make animations, I drag the objects into the viewport, add them to a sequencer and move them around. The first frame typically differs from where the characters were dragged to, so when rendering begins, the object is zipped across to where it needs to be on the first frame. This greatly upsets any cloth simulation, which then never recovers or completely disappears as a result.
To prevent this from happening, I loaded my sequence, then copy/pasted the values for transform, location and scale to the resting object as it shows without the sequence being open. So open sequencer, move playhead to first frame, copy value, close sequencer, paste to object, rinse and repeat. For good measure I’ve also loaded the same animation asset that I used for the character.
Cumbersome but solved my problem!
Another (somewhat easier) option we have is to turn our object into a spawnable. That way, the original object in the scene is removed and spawned in by sequencer when needed. For rendering this means the object gets spawned into the level at the location with the exact animation frame that’s supposed to be rendered on frame one. Both options work well.
For good practice we should also leave a transition period for complex poses so that the cloth can settle, or make sure to frame that part of the animation out. These tricks literally saved my bacon on the flying angel tests I’ve been working on all week.