Mesh with 1 bone from 3Dsmax causes blank scene

I am making a scene where I need to swap lots of objects in the scene, and making single objects as children of a bone does not work well in my workflow for a couple of different reasons. Therefore I decided to make all meshes skinned with 1 bone.
My scene was working perfectly before in the sandbox preview, but since I started doing this, the scene would go blank.
I tracked the issue to exporting a single element with 1 bone and the scene would still be blank (I can see the object on the hierarchy, but not on the viewport, and the dev wouldn’t be able to see it on his scene either).
I added one more bone to influence the mesh and the mesh showed up again.
For now and on, I will just add a second dummy object to each skinned mesh, but it would have been time saving to see some sort of console error or something that lead me into knowing i cant use a single bone on a mesh. Thanks!

I am really out of my Blender sphere, but parenting a mesh to a bone would need to also add matrix weights to the vertices of the mesh.

Parenting a mesh to a bone also works in Blender, but will not export. As the US west coast wakes up, to may get a better answer.

BTW, a single bone skeleton is of no real value unless some vertices move / rotate / scale more than others. Is this just a test?

A repro in the playground would be awesome as I am not sure if it is an exporter problem or a runtime one.

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Adding @Guillaume_Pelletier in case this is a known issue. Can you provide the 3dsmax scene that has this problem? Also, are you exporting to glTF or Babylon format?

Hi again! sorry for the delay! I was looking for the time to create a scene to test out.
Here is the 3Ds Max file: Dropbox - Babylon_1boneProblemScene(withBot).max - Simplify your life

If I export only the robot on the left, I get a blank scene in the sandbox.
If I export only the robot on the right, I see it dancing in the sandbox…
The only difference is that the Head geometry has only one bone assigned on the one on the left, and 2 bones assigned on the one on the right (and even then, all vertexs are assigned to only one bone)

It’s not a big deal for my workflow to add a bone or two… but it would be interesting to find out what’s going on.
thank you!

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And just in case you want to see those glbs without opening Max:



@Guillaume_Pelletier will be able to have a look soon, thanks for the files

Back on track, i will have a look soon.

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@LucasGuzman3d could you share the max scene, again, the link has expired. Many thanks.

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Hi all, for info i manage to find the issue. PR done. Happy Xmass. :santa:

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You rock @Guillaume_Pelletier