Why UE 4.5 crashes on FBX import randomly?

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I managed to import a couple of assets in the with fbx. then suddenly from one day of another withou changing any enviroment settings the crashes started. The larger the file the more unstable the Editor seems to react.

i’m pretty new to UE4, but every asset i’ve created in blender and imported into UE4 has crashed UE4…
(out of the 9 crashes, i’ve only sent in the report of one)
im going to keep up with learning blender, hopefully it’s something i’m doing wrong on that side and not UE4’s problem…

I import fbx from all sorts of programs. rhino, 3ds, sketchup. c4d.
sketup produces the biggest crap. so most of the time i have to opimize zu UVs etc. But out of nothing UE started to crash on larger files.

UE 4.3 seems to be way more stable regarding the fbx import. Try to keep the geometry as clean as possible!

But still fbx import is like playing roulette. As I believe this is crucial to most game developers I hope that there will an ease soon.

4.5 Is still marked as not stable. You might wanna use 4.4 or 4.3 until 4.5 is released :wink:

i’m juggeling with 4.4 4.5. I am big fan of the media framework. Video streaming is essential and it looks incredibly awesome with the engine…

i got UE4 on friday and im using the version it installed “unreal engine 4.4.3” every mesh i’ve created in blender, and imported into UE4 has crashed UE4. sometimes immediately, othertimes ~2minutes into the game while moving the object. (for example of one thing i’ve made) i followed the cup tutorial on youtube, and made the cup. saved it as .fbx and imported it into ue4. after messing around dragging the golfball size cup around it crashes. i then made the glass cup + napkin tutorial and saved the file as .fbx when i tried to import that one it crashed immediately. (im assuming it’s because i didn’t save the animation sequence or some how disable the sequence, i’m still a blender noob too, trying to learn both)

@Zerillium: @ray_be: I’m very interested in this issue as I use the FBX import all the time and have rarely encountered import issues as severe as you’re both mentioning. There are some crashes that will happen with reimporting somethings with importing animations that may cause issues that I’m aware of.

Would either of you mind uploading a test asset that is known to crash for you in FBX format along with linking the youtube video you mention you worked from.

Also, is this crashing in a new scene or in a project you’ve been working from and changing settings with? The easiest way to rule out some things is by using a default blank scene and see if the crash is still happening. It can help us narrow down potential elements much more quickly.

Thank you!

Tim

The max file size for attachments are 5 MB. The files that are most likely to fail import in 4.5 are bigger than 20 MB.
I managed to get things done with pingponging 4.4 and 4.5…

If you want you can post a link from something like GoogleDocs or Dropbox with the asset or you can send a download link via a private message on the forums as well.

I’ve not had any issue with files larger than 20mb though. I’ve often imported files that are larger than this size, especially when the FBX has embeded media with it.

As one example the other day I imported a 700 mb file size with no issue. It did take an hour to import (which is expected with that type of file size and my system specs), but had no issues aside from waiting.

Thanks!

Tim

Hi all,

I’m going to mark this as resolved for our tracking purposes. I’ve not been able to get any sort of repro or experienced this issue that was directly related to something wrong with the mesh itself.

If anyone has a repro that is happening with multiple meshes (a combination of your meshes and epic related content preferred to rule out user created meshes) where this can happen on a regular interval I’d be glad to look into this further.

Thank you!

Tim

I had some bad FBX files that would give “multiple roots” and “duplicate joints” in 4.4.2 but outright crashed 4.5 instead of giving out a proper error message.

@Pedro_Clericuzzi:

I’m not able to replicate this issue with the crash. Your issue is a separate crash issue though and should be posted as a separate question.

As far as the issue though. I can create multiple roots and joints and get the warnings when Importing in 4.5.