There were two reasons the USD Exporter was listed as experimental:
- Originally there was no deduplication of mesh normals & UV coordinates
(resolved in rBf5e00f735106b5ec635806a4c795a2bc46ae8369), and
- the way materials were exported was incompatible with instancing with
USD 19.07. This seems to be resolved with the current version of USD
(19.11).
Blender (more specifically, `makesdna`) doesn't seem to like empty DNA
structs, so I couldn't remove all properties from
`UserDef_Experimental`. Instead I have just kept `char _pad0[8]`.
Reviewed by: campbellbarton
Differential Revision: https://developer.blender.org/D6519
7f3e121926