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I'm trying the new Sub model merging feature, which according to the latest docs enters in Beta, so it's supposed to be ready for testing.
But when I try to use it, enabling the option to export as Sub model ( regardless if it's enabled from the Babylon page, or from the Multi exporter Options ), creates an an empty .GLTF with a 0-length .BIN file.
The object to be exported is a Skinned mesh character, with 5 LODs, each one on its own Layer named LOD0, LOD1, etc., plus an additional Layer named "RIG", with just the animated hierarchy made of 3DS Max Dummy nodes, which would normally be exported in a separate animation .GLTF file.
This works perfectly fine when the model is exported normally, with each LOD calling into the separate animation file through the <AnimationFileList>, which is listed as "Deprecated", with the suggestion to use Sub Model Merging instead.
In all cases ASOBO_animation_retargeting and ASOBO_unique_id are enabled for both the meshes and the skeleton, and exporting the old way doesn't give any errors about duplicated Id's, it all works, animations works, LODs do switch fine, and the character even works as an Attachment to another vehicle ( great new feature, BTW ).
It's just the sub model option I can't manage to use.
While exporting from the Multi Exporter doesn't give any errors, just a very fast export with those empty files, exporting from Babylon page results in the following, depending on what is selected:
1) If only the active LOD Layer (which contains only the skinned mesh ) is visible on screen, pressing Export results in Empty GLTF/BIN files
2 ) If I select the Skinned Mesh before Exporting, it gives the following errors:
"More than one root node for the skin. The skeleton bones need to be part of the same hierarchy. The Skin cannot be exported"
"Export Canceled: Sequence contains no matching element" and then a .NET Exception "Sequence contains no matching element" in System.Linq.Enumerable.First
3) If I select the whole animated hierarchy (which was on the hidden "RIG" layer until now, so I enabled the layer and selected the whole hierarchy and the skinned Mesh at the same time ), it still give the "More than one root node for the skin. The skeleton bones need to be part of the same hierarchy", however the .GTLF/BIN files now seems to be valid.
But isn't this resulting in merging both the Mesh and the animation in a single .GLTF, defeating the purpose of having a separate animation file shared by multiple LODs ?
Also, why the different behavior if the object to be exported is selected or not in Max, considering the "Export only selected" option is Disabled ? Shouldn't that option always export what is visible at any given time ( assuming "export hidden objects is also Disabled, of course ), and not being affected by what is actually selected ?
