Cheetah3D JAS & FBX Files Don't Import into Unity 2020 or Later

Starting with Unity 2020, models created in Cheetah3D 7.5.1, JAS or FBX, do not import correctly. There are two problems: (1) Materials lose their texture assignments, and (2) Textures render as solid colors. The same models created in Cheetah3D import correctly into Unity 2019 and earlier. Models created within Unity or FBX files created in Cinema4D import and/or render correctly in Unity 2020 and 2021, which leads me to believe this is a problem specific to files created in Cheetah3D.

I've reported this as a bug to Unity, and posted about it in their forum, but I've not gotten any response. I don't know if this is a Cheetah3D issue or a Unity issue, but it's a serious issue for me. Anybody use Cheetah3D with Unity? If so, have you run into this problem, is there a work around.
 
I guess you need to maintain a folder collecting all parts related to the asset (FBX or JAS and textures) otherwise Unity won´t find them. In this case you can locate your Unity project folder/Assets and drag+drop whats missing and tell inside the inspector which folder it should use.
Here´s the standard AlienWalk with animation and textures applied inside the latest Unity version (2020.3.9f1):
AWinUnity.png
 
I guess you need to maintain a folder collecting all parts related to the asset (FBX or JAS and textures) otherwise Unity won´t find them. In this case you can locate your Unity project folder/Assets and drag+drop whats missing and tell inside the inspector which folder it should use.
Here´s the standard AlienWalk with animation and textures applied inside the latest Unity version (2020.3.9f1):
Yes, I understand how assets work and where to put them. I've been using Cheetah3D with Unity for many years. This is something I've seen once before, but then it was when updating Unity projects to 2020 from earlier versions. The solution then was to update in smaller increments, not an option with new projects.

And yes, I can assign the textures to the materials after import, but that doesn't solve the 2nd problem, textures don't render in Unity.

The attached image shows the same model, saved in JAS format, in Unity 2018 on the left and in Unity 2021 on the right. It's the same if I export in FBX format.

Unity Materials.jpg
 
What kind of texture is this?
Renders here as usual:
A PNG file. Nothing unusual: Create a cube primitive, create a material, select an image for the material, assign the material to a cube, save. Same as I've done MANY times before. Doing the exact same with C4D, it imports/renders correctly.

Your example was created/saved in Cheetah JAS format? What version of Unity?

No idea why it would lose the material texture assignments, but it looks like the rendering problem might involve UV mapping, like maybe the texture is scaled way up.
 
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Unity version as said above: 2020.3.9f1
I´d say skip .jas files - they seems no longer handled as full-featured assets - for which the Unity team is probably more responsible by changing/buying more and more separate components for the integration into Unity (Guess where the name comes from.;) As you might already know they bought Peter Jackson´s WetaDigital for its graphics and VFX tools/software and "engineering talent").
Back to:
Cheetah3D-FBX to Unity works.
You´ll need (to wait) for the ".fbm" folder for its creation which contains the materials. If it won´t happen automatically open the just generated FBX file and the folder will instantly pop up out of nowhere. Now drag these 2 objects (.fbx+.fbm-folder) into your Unity Project Assets folder:

FBX2Unity.jpeg
 
No idea why it would lose the material texture assignments, but it looks like the rendering problem might involve UV mapping, like maybe the texture is scaled way up.
I doubt that because all of C3D´s primitive/parametric shapes (with the exception of Polyhedra) have default UVs. Even Spline generated objects get UVs.
 
Unity version as said above: 2020.3.9f1
I´d say skip .jas files - they seems no longer handled as full-featured assets - for which the Unity team is probably more responsible by changing/buying more and more separate components for the integration into Unity (Guess where the name comes from.;) As you might already know they bought Peter Jackson´s WetaDigital for its graphics and VFX tools/software and "engineering talent").
Back to:
Cheetah3D-FBX to Unity works.
You´ll need (to wait) for the ".fbm" folder for its creation which contains the materials. If it won´t happen automatically open the just generated FBX file and the folder will instantly pop up out of nowhere. Now drag these 2 objects (.fbx+.fbm-folder) into your Unity Project Assets folder:
The models were created and saved in the Assets folder of a new project. The texture was also in the Assets folder when the model was created. This is one of a few different textures I've tried. Nothing was moved or copied. Previously, this always worked, both Cheetah and Unity had no problem finding the files and assigning the textures on import. Though, assigning the textures is a minor annoyance I can work around. But the MOST important problem is the textures not rendering in Unity.

The format doesn't seem to matter, saving it with Cheetah3D seems to. The attached screen capture shows the Game panel, from left to right: Cheetah3D JAS, Cheetah3D FBX, Cinema4D FBX, and Unity cube (3D Object) in Unity 2021. The cube on the left is currently selected.

Model Comparison.jpg


FWIW, Unity converts JAS files to FBX on import. It uses Cheetah3D to do the conversion, which is why it must be installed for Unity to be able to open JAS files. That suggests to me it's something to do with the way Cheetah3D exports FBX files. Saving in JAS format is just a convenience, it should make no difference.
 
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Unity and Cheetah3d have been gone through so many iterations I´m wondering if the import will still work at all. From my experience and shown above it´s broken.
Can you please upload a sample file as I still can´t replicate the rendering issue you mentioned?
 
Unity and Cheetah3d have been gone through so many iterations I´m wondering if the import will still work at all. From my experience and shown above it´s broken.
Can you please upload a sample file as I still can´t replicate the rendering issue you mentioned?
A sample Unity project or JAS file? The Cheetah3D file is just a cube and random texture (PNG image). The Unity project is just a new project with the model and texture in the assets folder.
 
I added a simple rotating textured cube installed via drag&drop into the Unity Editor Assets panel.
I can´t determine any issue.
UnityTest.jpg

Added FBX asset for you.
 

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Interesting. Attached is my Unity 2021 project with your cube imported. Unity did import the materials/textures correctly, but it still does not render them. Could this have something to do with running macOS 10.14.6? Your cube does import and render in Unity 2018 for me.

Rotating Cube.jpg
 
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Strange. Website says:

Unity Hub system requirements

OS:
Windows 7 SP1+, 8, 10, 64-bit versions only; Mac OS X 10.12+; Ubuntu 16.04, 18.04, and CentOS 7.
I wonder if there´s a render option we´re overlooking. I can´t find any setting to force such rendering.
 
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I had what might be a related problem a while back when I was trying to update older Unity files from 2017 to 2018. There were problems related to importing models (among other things). However, when I ran 2018 on a Mac with an older system, 10.11 I believe, they imported correctly. Once updated on the older system, I could then open them in 2018 on my Mac and update them to newer versions without problem. Maybe Unity doesn't get along equally well with all versions of macOS.
 
That doesn´t seem to explain the rendering issue - or does it?
I only use Unity for evaluation. The installation process alone drives me up the wall. When I updated yesterday, there were suddenly 2 Unity editors and the whole baggage swallows about 20 GB. So I completely removed it and made a clean install which means I need a new license file OMG. Well, Unreal is even more massive.
I´m really sorry of being not of better help with your issue.
 
That doesn´t seem to explain the rendering issue - or does it?
I only use Unity for evaluation. The installation process alone drives me up the wall. When I updated yesterday, there were suddenly 2 Unity editors and the whole baggage swallows about 20 GB. So I completely removed it and made a clean install which means I need a new license file OMG. Well, Unreal is even more massive.
I´m really sorry of being not of better help with your issue.
Doesn't explain, just that the same version of Unity can behave very differently on different machines, working on one and failing on another, IME.

I think what it boils down to is that Cheetah exports an FBX format that Unity may or may not be able to import correctly. (Any idea what version of FBX Cheetah exports? C4D lets you select the FBX version.) The problem didn't exist (for me) in Unity versions prior to 2020. I've been using Cheetah to create models for Unity for many years, for almost as long as Cheetah has been around. I don't know whether it's because of the way Cheetah exports or the way Unity imports FBX files, something's changed. When I eventually do update macOS, the problem may go away, but I'm not ready to do that yet.

So I'm stuck. Do I change my workflow to use another 3D modeling program? If so, which one? I'm not going back to paying the hefty subscription rental fee for Cinema4D. Or just hold off on new projects in hopes of future updates fixing things?

FYI, I currently have 15 different versions of Unity installed, from 2021.1 going back to 2017.2. I recently deleted a few older versions. :D
 
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Do you know what FBX-version the other 3D software you mentioned successfully use?
Cinema4D has several FBX version options, from 6.1 to 7.5. I believe I used the default, 7.1. I just tried with C4D FBX 7.5, and it imports and renders correctly. In the past, we've experimented with exporting different FBX versions from C4D, and I believe they all work equally well with Unity.
 
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