Aras Pranckevicius
d76583cb4a
As part of the previous fix (D15410), the importer got code to track min & max vertex indices used as part of the mesh faces. However, if faces refer to a "sparse" (i.e. non-contiguous) subset of all vertices, then the imported mesh would contain all the vertices between min & max range. Replace that with proper tracking of actually used vertex indices for each imported mesh. Fixes T100302. This does affect import performance a tiny bit, e.g. importing Blender 3.0 splash scene goes 21.7s -> 22.1s, and importing rungholt.obj goes 2.37s -> 2.48s. Importer related tests have a bunch of vertex changes in them, since now vertices are added in the order that the faces are referring to them. Which incidentally matches the order that the Python based importer was creating them too.