Cloth morph target crashes

Hi if I enable cloth morph target on an attached skeletal mesh, which has APEX cloth, then either play or switch to the view port the editor crashes.

Is this a bug ? what more information would you like ?

Regards WJones

Hi WJones,

Can you please include the following information:

  • Call stack from the crash reporter windows
  • The Machine/Epic IDs that come up in that same window.
  • Logs from the crash in Project Folder > Saved > Logs (attach the text file here)
  • If you have a simple test asset that can reproduce the crash consistently this would be helpful, but is not necessary. I will have to create one and see if I get the same results. It’s just helpful if one is readily available. :slight_smile:
  • Does this happen in a blank project as well or only in your project?

Thank you!



I am setting the morph target by casting the cloth mesh to an Anim Instance, in the construction script.Is that the right way of going about it.


The stack trace, with machine IDlink text


link text


Do you need anymore info from me.


would you be willing to provide a sample project that reproduces this with a link here to download or you can send privately via the forums.


I prepared a blnk project, and the crash doesn’t occur. So I am not sure what that means, does that mean we still have a bug ?

However in the blank project the behavior isn’t right morph targets aren’t showing at all. I attach a screen shot of the construction script where I am trying to set them.

Any thoughts ??


Tim further investigation:

If I set one morph targets in the event begin play the first one only will work ! With cloth simulation and cloth collision with collision volumes !

HOWEVER… the morph target ONLY effects the mesh where there is cloth max distance is set. This is easily over come by setting a 0 value to parts not subject to simulation.

BUT as I said, only the first morph target works, any further morph targets don’t show, but ruin performance taking 8 FPS down to 16 FPS.

So while I move closer, things aren’t right still.

Hey sorry for the delay on this one. Can you provide a simple project that reproduces the issue? I cannot get this crash to happen.

I can submit a ticket with the call stack and log above, but without being able to reproduce locally this may present a problem when trying to reproduce and look at the issue. let me know.


The crash doesn’t occur in a fresh project, also in 4.12 the frame rate doesn’t drop either.

So please feel free to mark this one as closed. Thanks for the help, but it looks like this one kinda solved it self.