[Epic Official] FBX Import Reporting

ianoreo · July 27, 2014, 1:21am

So I just checked my export settings for FBX, it looks like it was set to “Automatic” in Maya (1.0). I have noticed the export appears incredibly small by default in UE. I just set it to centimeters (about 30 for scale factor by comparison), and the problem seems to be gone! Although I still get the all bones missing from bind pose error, the animation correctly displays upon import. Thanks so much for you help, ! Was this the correct way to fix the issue?

Very best!

AnadinX · July 27, 2014, 1:45am

Just curious, try triangulating this before importing it to UE4. You are right in that the FBX looks fine - can you see those triangles on the other side in UE? - I am thinking it might be flipping some when triangulating

AnadinX · July 27, 2014, 3:06am

Certainly sound like it cm is the correct sizing for UE4. I use C4D and I get the missing bind pose thing too and its not been a problem for me - I assume it’s sometimes a spurious error.

Gabor_D · July 27, 2014, 8:17am

The normals looks fine, no flipping. But triangulating the mesh manually before the fbx export solved the problem, everything looks perfect in UE4 :). Many thanks for your help !

anonymous_user_f1b5294d1 · July 27, 2014, 10:11pm

Thanks for looking into this Eric. I thought it might have to do with trying to import the entire scene at once, but i have larger scenes that have come in and built just fine. "although those were hand modeled and the one that is having the issue is procedurally generated. So I have broken down the scene into blocks.

Yes i did have the engine on my D drive until i had to send in my computer for repairs. When installing it i moved it to my c drive. Do i need to remove all and install a final time, or how do i get rid of the disc drive issue?

Thank You

anonymous_user_f1b5294d1 · July 27, 2014, 10:13pm

I didn’t move it manually i did use the installer and installed it to C

AnadinX · July 27, 2014, 11:45pm

Awesome, glad I could help

Antidamage · August 6, 2014, 12:23am

Sorry, this file has been removed as the result of a fraudulent DMCA notice. I’ll update again later when it has been restored.

Chwindor · August 14, 2014, 10:05am

Hello, I exported this fbx file from blender and there are Japanese characters in the name of bones. When I tried to import it to UE4, those none English characters become ‘???’ and the Engine gives out an error like this and import ends up failed.

I tried to import this fbx file to 3ds 2015 and succeeded. I am no so familiar with modeling, but I guess this might be a character encoding issue. I have already checked the “Character Encoding” page in Program Guide, so if it is my matter to change those none English characters, please tell me.
The link to the fbx file: A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums.

KVogler · August 22, 2014, 11:21am

Hi,

I have problems importing some meshes. Some faces of the mesh are missing (inverted?). It seems only to happen with meshes that were constructed with some booleans involved. I had converted them back into editable polys before UV mapping them. Other meshes that are just simple boxes or have just some bevels/insets import fine. Also in one case it worked for a door.

I have added a file containing the following:
–The FBX file(s) that I used. “InnerWallWindow” is the troubling one. (while Inner WallDoor looks just fine).
–The scene file from which the fbx files were exported.
–The textures that were used (for completeness)
–The UASSET files that were cerated by the engine on import.
–A couple of screenshots illustrating the problem.

The file is available here: A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums

I hope that helps a bit when looking into this.
If you need more information, please let me know.

Cheers,
Klaus

UPDATE : Thanks to the problem was traced down to offending Ngon geometry. Maybe you can still check out why they are not getting imported corerctly while others do…
-Klaus

iniside · August 24, 2014, 2:23pm

Very easy to reproduce. In modo settings, change Up axis from Y to Z. Then, just create any mesh (best to create Cone, as it shows issue very clearly). Export as FBX 2013.

Import to Unreal. Z and Y axis are flipped.

I don’t know if that is the issue with importer or exporter. I bet it’s rather exporter, but I have reported this issue since 701 to Luxology and it haven’t been fixed. Maybe you guys could poke them, to add some simple switch to FBX exporter which will allow to, set up axis ?

Z Axis Issue

anonymous_user_5facb26d1 · September 4, 2014, 11:56am

I’ve had no problem importing static meshes, but importing skeletal meshes seems to be a royal pain (Or I’m simply doing it wrong). I already made a post, but there’s no resolution: https://answers.unrealengine.com/questions/91381/error-when-importing-fbx-skeletal-mesh-from-blende.html

DyotoOrion · September 5, 2014, 5:31pm

Hi! I am experiencing a problem with Skeletal Meshes made in and exported from Blender 2.71.6, when Imported into Unreal Engine 4. Both Unreal Engtine 4.4.1 and 4.2 experience the same problem. I do not know really whether the error is Blender’s FBX Exporter or UE4’s FBX Importer which is why I have already submitted a bug report to the Blender Foundation and so am repeating that Bug Report here for Epic Games to take a look at. That being said I suspect the error is with Blenders FBX Exporter. Any ways:

Here it is.

System Information
Operating system and graphics card

OS :Windows 7 Professional 64 Bit. Service Pack 1.

GPU: ASUS Nvidia Geforce GTX 780Ti. Driver Version 9.18.13.3788

Blender Version
Broken: 2.71.6
Worked: (optional)

Short description of error
A spaceship model with animated parts made in Blender. With two animations. A canopy open animation and a landing gear down animation.
Both animations work absolutely fine inside Blender. However when exported as an FBX file and imported into Unreal Engine 4 version 4.4.1 or 4.2 the result is that some of the bones in the Armature have been moved. It looks as though they have been snapped to their parent.

This does not make any sense because I am using the exact same Mesh and Skeleton which has not been changed at all, but that worked
fine when exported with Blender Version 2.70, with its version of the FBX Exporter and imported into Unreal Engine 4.2 But now that I use that
same Blend File with Blender 2.71.6 I get bone translation errors inside Unreal Engine 4.

Exact steps for others to reproduce the error
Based on a (as simple as possible) attached .blend file with minimum amount of steps

Inside Blender - Make a single Mesh Object with two mesh parts inside it that are not connected by joined polygons. For example a Car and a Car Sun Roof.
We also need to add a Sun Roof Mover mesh inside the Mesh Object to move the Sun Roof. So inside the Mesh Object we have three unconnected Meshes,
Car Body, Sun Roof Slider and Sun Roof.
Let us imagine that we want the Sun Roof to to be able to slide backwards, but also to tilt by say 45 degrees.
Add an Armature at world location 0,0,0. With the Armature selected enter Edit Mode. Name the single bone “Root.” Create another bone
at the exact same location as Root and name it “Car Body”. Create another bone and move it to a location just behind the Sun Roof and name it
“Sun Roof Mover.” Make another bone and move it to the approximate centre of the Sun Roof and name it “Sun Roof Rotator.” We now have 4 bones.
Parent Sun Roof Rotator to Sun Roof Mover. Keep Offset. Parent Sun Roof Mover to Car Body. Keep Offset. Parent Car Body to Root. Keep Offset.
With the Armature Selected enter Edit Mode and with the Pivot Point set to 3D Cursor and the 3D Cursor located at world space 0,0,0 scale the Bones
by 100 - S, 100, Enter.
Select the Mesh and enter Edit Mode. With all Vertices selected and the 3D cursor at 000 scale the mesh by 100… S, 100, Enter.
Select the Mesh Object and with Shift held down select the Armature. Parent the Mesh to the Armature. With Empty Groups.
Assign all the vertices of the Car Body to the Vertice Group “Car Body.” Assign all the vertices of the Sun Roof Slider to Vertice Group “Sun Roof Slider”.
Assign all the Vertices of the Sun Roof to the Vertice Group “Sun Roof Rotator”.
With the Armature Selected enter Pose Mode. Select all the Bones and Insert a Location and Rotation Key Frame. Move the Timeline to Frame 40.
Select the Bone “Run Roof Slider” and move it along the Y Axis 3 Blender Units. The Sun Roof Slider and the Sun Roof itself will be moved because the
Sun Roof Rotator is parent to the Sun Roof Slider. Select All Bones and insert key frames Location and Rotation. Move the Timeline to Frame 80 and
select the bone Sun Roof Rotator. Rotate it 45o and select all Bones. Insert Location Rotation.
Now in Blender you have an Animation 80 frames long that features the Sun Roof sliding backwards and tilting 45 degrees. Great! Working as Intended.
Select the Mesh Object and then with Shift held select the Armature.
Export as FBX. Check “Selected Objects” Change Smooth groups to “Face” from the drop down menu. Everything else is default. Export as FBX.
Import into Unreal Engine 4. On the Import Window, check “Import Animations.” Import the Skeletal Mesh.
Open the Skeletal Mesh inside the Skeletal Mesh Viewer - Persona - and view the animation.
You will see that when the Animation is played inside UE4 the Bones have been incorrectly translated. It looks as if any bones that Inherit Location, have failed to Inherit Location from their parent Bones. Or alternatively they have been snapped to their parent.

I don’t know why. Please help!

So as an example of this error I include a Blend file.

https://drive.google.com/file/d/0ByTG1Z_4SBShTFdQeVJNbzJVWFk/edit?usp=sharing

This Blend File contains a simple “Car with Sun Roof” Mesh and Armature and an Animation for the Sun Roof.
My spaceship for my computer game project features an animation similar in design to the Sun Roof animation on the car. That Skeletal Mesh also has the same errors inside UE4, that of incorrectly translated bones.

I hope that you guys at Blender Foundation can figure out what is going wrong here and help to fix it. Thanks so much!

Yours faithfully,
Russell Morahan

To Epic Games: This Bug Report has been assigned to a Blender Developer who is investigating this issue. I would be happy to put Epic Games in contact with that Blender developer if they think that would be helpful. Please PM me if you would like me to do put you, Epic Games, in contact with the Bender Developer assigned to this task. Thanks!

anonymous_user_848b907e · September 15, 2014, 11:54pm

Hi there,

I’ve noticed some strange behavior with the static mesh import in the lastest version of the engine.

It seems that the engine split all vertices during the mesh import (same goes for LOD Levels).

Before updating to 4.4.2 a rock 308 verts/ 612 triangles in Maya 2015 had the same amount of faces and vertices in the Unreal Engine.

Now after the update the same rock has 308 verts/ 612 triangles in Maya, but 1742 verts / 612 triangles in Unreal…

That is weird, since even if you would split every since vertex on the mesh you would only manage to get 924 vertices.
I’ll provide a mesh and screenshot’s after I’m at home

AnadinX · September 16, 2014, 12:39am

That sounds like Epic fixed the count in UE. you should expect to see a 1.5 to 2.7x increase in verts from Maya/C4D/Modo etc. to the realtime count due to hard edges, UV breaks etc. are you UV’s unwrapped like a light map UV?

anonymous_user_848b907e · September 16, 2014, 7:10am

The UV’s are unwrapped, but we use only a single channel since the game is an open world RPG with fully dynamic lighting in the exterior world. Those mossy rocks will not be used in interior cave levels.

ok, but what is the advantage of having such a high amount of vertices? Will it have influence on the performace? What was wrong with the vertex count the meshes used before the latest engine update?

AnadinX · September 16, 2014, 7:22am

Like I say, I would think it’s possible that its just more accurately reporting now, BUT that does seem high. 308 verts * 2.7 would only be 831. It’s more a problem that normally DCC apps don’t report the real number of verts used. If you have a cube (12 verts) at best it will be 18 I think due to UV breaks and thats only if you have smooth edges, if you break all the edges to make it look like a cube it ends up being 24+ depending on UV breaks. Each break for smoothing and or UV’s doubles the vert count of the attached edges. So while I think you should see an increase in the vert count (to show the real cost of the verst in realtime rendering) I do agree with your point that 308 to 1742 is a bit high. The only way I could see that happening is if every edge was hard and all the faces where their own UV islands.

AnadinX · September 16, 2014, 8:04am

Yeah so you would only expect double up verts along the UV island edges then, it is possible that Maya is actually reporting the realtime vert stats - is that an option? I use C4D and just work to the rough 1.6-2.7x count expected in game as C4D only shows me the vert count of the mesh, not the extras generated for edges/uv’s

anonymous_user_848b907e · September 16, 2014, 7:51am

Thanks for your reply, .
I’ve reimported the exported fbx again in Maya in it has again it’s 308 verts.

The only hard edges are the border edge of the UV islands. The texture itself is seamless painted in Mudbox.

I really can’t imagine how UE4 will generate this crazy amount of vertices

anonymous_user_848b907e · September 16, 2014, 9:08am

Thanks,I’ll look if Maya has some sort of output for realtime stats.

How will the higher amount of vertices influence the performance? Are they used for rendering only once when the scene loaded or are they rendered every frame?