I read a lot of questions about this in the forum and I also asked myself if it would be possible to implement a lightmap export for the 3ds Max Exporter so that the Lightmap can be loaded in sandbox.
The following pictures are done in Photoshop, but could show a way of how to set this all up using the already existing MOZ_lightmap Extension. This would make the babylonJSExporter a even more powerful Tool to use.
That said here is how it could work:
Set up the Lightmap in a Custom BabylonSlot in the PBR-Material.
Check the ExportSettings to use the Extension
This is the Extension and how it is saved in the gltf or glb
the loaded Lightmap in the sandbox
Please consider this. This would be very helpful for a heck of artists.
Let me know your thoughts and keep up the good work.