Export Requirements to address Model Distortions

[DotaWorkshop]

If you are experiencing stretched and distorted models when compiling in our item workshop tool, be sure to:

1. Import Valve's reference model and export your item model with your importer/exporter set to a scale factor of 1.0
2. Export your model in its static default bind pose with no animation
3. EXACTLY match the scale, positions and rotations of the joints in Valve’s model bind pose if skinned to a Valve skeleton
4. If you still have problems when exporting an FBX, try exporting a DMX if you have that option

You can also look at other solutions on our Item Troubleshooting page.

If you are still experiencing distorted workshop model compiles after following these requirements, please report them here by telling us:

1. What software you are using to author your items
2. What plug-ins you are using to export your files
3. Whether you are exporting in FBX or DMX
4. Whether you are using a Valve or a custom skeleton

Thank you.

[Konras]

Hello,

After speaking with few workshop artists here is what we came up with.

1. There is a huge issues with FBX exports from 3D Studio Max. Most models are rotated 90 degrees to the left. That looks like they would have Y and Z axis switched.
Even when importing FBX from workshop technical page and exporting it again with 3DSMax FBX this problem will occur.
When importing Rubick FBX to 3DSMax his mesh has +90 degrees rotation on X, and his root bone has -90 degrees rotation on Z.

In some cases including parent bones all the way to root bone in skin modifier helps, but this is not 100% fix.
100% fix is to import base from SMD file using for example WallWorm importer. This worked for Naga Siren (SMD files from workshop download page).
After importing SMD we can export FBX and it will work. However as soon as we will import that FBX and export it again it will be broken.
Because of that it seems that FBX importer in Max converts mesh very badly to Zup system.

2. Standard 3D Studio Max 2016 FBX exporter.

3. FBX. I found no way to work with DMX in Max.

4. Valve skeleton.


To test it out please import siren_hair.fbx from download page in 3D Studio Max. Without changing anything please export it as FBX file. Item will be broken after testing it in importer.
Let me know if you would need any more information.

Thank you for your time.
Konrad Krzeminski.

[Tvidotto]

1. There is a huge issues with FBX exports from 3D Studio Max. Most models are rotated 90 degrees to the left. That looks like they would have Y and Z axis switched.

Hey Konras, did you try setting on the fbx exporter to use the Y as the upaxis? That probably will fix the rotation on the file

[Konras]

Hi Thiago,

At the start, sorry for a wall of text.

I think I made a mistake while checking Naga Siren last time. I assumed that root bone was included in her skin modifier, but that was not the case in default FBX from download page.
After adding whole bone chain from root bone everything works.

I also tested exporting Zup and Yup. Both cases without root bone dont work.
I exported both files to ASCI format and looked into them. Vertices in both files have exactly the same coordinate. The only difference I saw is the GlobalSettings section that pave different parameter Values depending on which axis was set up as UP.



ROOT bone seems to fix everything thanks to its -90 degree rotation on Z axis.
Here is a screen from max scene.



Adding root chain to skin modifier also changes BindPose section in FBX by adding a lot of additional transformations, that maybe are the reason that fix the problem.

Here I include a link to files I exported and a 3DSmax2016 scene I worked on after importing siren_hair.fbx from download page. Maybe it will be any help.
https://1drv.ms/u/s!AgJrwngs7I44nQB4MKhII1gSVYLS


3DSmax is also to blame, as it sometimes remove bones that are not bind to any vertices in skin modifier.
I think it is happening on import as file head_ROOT_added.FBX from my package when imported to max will not have root bone under skin modifier, despite it beeing exported with one added. This file will not work when exported as is.
I have also for test made a file that has all bones from chain affecting mesh in some way. Then 3DSmax is not removing them. And that file will work when import/export again. Its called head_ROOT_bonesRigged.FBX

In the end I suggest people to add whole bone chain from root to skin modifier.
Also make sure always that whole chain is present under skin modifier when exporting.
Sorry for previous confusion. Should have checked Siren more carefully.

As always if you need any more info, please let me know.
Konrad Krzeminski.

[Tvidotto]

ROOT bone seems to fix everything thanks to its -90 degree rotation on Z axis.

thanks for pointing that out, I will add this to the support page

[Tvidotto]

done!

[ssolidus]

hi im new here... someone knows something about how to export to fbx a sven sword.....(rotate bones)(rotate pivot point) i tryed everyting no results the weapon float around im rigging it to sword_1