Editor changes Animation Curves?

Hi guys / girls,

I recently switched to Maya 2016 for making meshes and animations which works quite well but I now discovered a huge problem with all my animations and I dont really know if it’s a bug of the engine or not.

The problem is that my animations dont look the same in the editor as they do in maya (or any other program which can open fbx animations). In fact if I export the animation from the editor and import that into maya I can see that the animation curves are different.

Here you can see the animation I made (white joints) and the animation that unreal changed it to (light-blue joints).
You can also see the animation legnth which is 26 frames… the red keys are mine. on every frame there is a red keyframe. the blue ones are from the imported animation from unreal where you can see the first keyframe is the same but there are only 25 keys on 26 frames and they are on decimal frames.

Here is the animation in the editor… Also on frame seven as above. You can see the arm rotation is not the same I made.

If I open the graph editor in Maya and look at both animations just on the arm, the differences are clearly visible.

The dark blue, red and green curves are the from the animation I made just on the left upperarm. The light blue, yellow and black curves should be identical because it’s the same arm just from the animation I exported from unreal.

Of course I already checked almost everything that could cause this error. I thought maybe it’s my exporting options but my animations in maya are sampled at 30 fps and all the other options are the same as in the fbx-export section of the documentation of unreal (I also tried many other options but no luck).
Here are my maya-general-options:

It’s worth mentioning that when I import the from maya exported animation again into maya or any other 3d program the animation looks right.

I also thought maybe it’s the import options from unreal editor but even if I dont check the use default sample rate (which should also work because the animation is 30fps) the results are always the same.

Does anyone know what could cause this issues and how to fix these?
Best regards,

does nobody have a solution for this or ideas what could cause this issue?

anyone ??

What version of the FBX exporter are you using?

It looks like this on my end.

It appears as though Maya 2016 may not be compatible with the 2014/2015 FBX exporter. Let us know if you continue to experience a problem with curves if you:

  1. Export from Maya 2016 with a 2016 version of the FBX exporter
  2. Export from Maya 2015/14 with the corresponding FBX exporter



So I finally had time to test this but I still see the same results… Any other things I could do?

Which of the above conditions did you test with, if either?

I tested both.

I’m having difficulty reproducing this on our end. I created a simple animation with a cube, adjusted the curves, then exported fbx from Maya/Imported into UE4, using “Exported Time” for animation length. I then exported that animation from UE4 and imported it back into the original Maya file. In the image below, the colored lines are the original curves. The black “lines” are actually dots as the curves have been converted to frames. However, both curves line up exactly.

Please try imported the animation with Exported Time in the Animation Length field. If this does not resolve the issue, please send a link to your original Maya2015 test file in a private message on the if possible. You can send a dropbox or Google drive link.

Ok here are some files from me. I put together a readme file so you can see what I tested step by step. If you import one of the maya fbx files and one of the UE fbx files into maya you can see the difference in the animation.

I finally had a chance to revisit this issue… Comparing your FBX files generated from Maya 2015 since Maya 2016 is not officially supported yet and has not been tested. I did see the difference in the curves as you have pictured above. However, providing the FBX files is not conclusive as there are variables involved in what settings were selected when exporting from Maya as well as variables selected when importing into UE4 that would result in different FBX data.

So I performed the following test:

  1. Created a “punt” animation with generic character
  2. Exported character and FBX from Maya 2015 with the 2014 Exporter (as pictured above)
  3. Imported into UE4 with animation included and “no skeleton” selected so it would generate it’s own.
  4. Exported Animation asset from UE4 to a new FBX file
  5. Back in Maya, renamed the root of the skeleton to “Root 2” and closed the file
  6. Opened a new Maya file and imported the FBX generated from UE4
  7. Renamed the root of the skeleton to “Root 3”
  8. Imported the skeletal mesh from the original Maya file (“Root2”)
  9. Compared the curves from Root 3 (from the exported from UE4 skeleton) to the imported Root 2 (from the original skeleton the FBX was generated from)
  10. RESULT: Curves were identical
  11. CONCLUSION: unable to reproduce the issue.

Please review the steps I’ve listed to see if I am not recreating the conditions that cause this bug properly. Also, if you’d like to send the original Maya 2015 files these were generated in I’d be happy to check those out. Lastly, taking the FBX that you provided with the “correct” curves generated from Maya 2015, I was able to export/import back and forth from Maya to UE4 with the same results by following the steps I’ve posted above. Please test this way and see if you do not get the same results.

*Another thing you can do to test if it’s an issue with the engine, test with UE4.10 and UE4.11 Preview to see if you get the same results.

Hi ,

So you said you can import my “correct” animation into ue4 and export it again and it looks exactly the same as it did before and the curves are the same?
But does it really look exactly the same in maya and in UE?

On my end the animation doesnt look good in UE at certain frames as you can see in the second picture I posted.
Can you please compare the animation in maya and ue and tell me if they look the same. (E.g.: Look at frame 15 in maya and in ue… it just looks weird in ue)

Another thing with my animation is that every two frames are identical… well in maya at least. In UE the frames are not identical… Can you confirm that or is this just happening on my end? (E.g.: Compare frame 14 and 15 - they should look identical but they dont)

Also same thing is happening in UE4.11. Even with animation exported from maya 2015.

I also tested everything on another machine now… The animations are wrong on that one as well…

Best regards, Joey

Since I have not been able to reproduce this issue with either your assets or using the UE4_Mannequin skeletal assets, I am closing this thread because it has gotten long without a clear answer. Also, there has not been any other reports of curves being distorted when imported into UE4 from Maya or any other 3D program.

However, if you feel this is indeed a bug, feel free to report this in the bug reports section and we will take another look with another support technician, as I may possibly be missing something. If you decide to you want to do this, please include a link to an FBX with the skeletal mesh and animation (not just the animation) to ensure we are comparing “apples” to “apples.”