Quote - Looking at some of the .ply files in Lux's Resources-objects folder using MeshLab I found they contain 6x the number of vertices compared to the .obj files imported into DAZ Studio, but the number of faces is the same as in the .obj's (!). If I then let MeshLab remove duplicate vertices that number shrinks to about the original amount, and the resulting .ply's exported by MeshLab are several MegaBytes smaller. Why are there so many (redundant?) vertices in those Lux .ply's?

A couple of reasons. First, Lux needs to have the geometry grouped by material, not by shape. So, that means that in several cases we need to create "seams", actually edges, where there are none, because that's where the material boundaries are.

Second, the way Lux works about UV maps is that it needs the maps to be "unwrapped", and the same UV point needs to be repeated twice if the point falls along the seam of the map. It is, in fact, the hardest part of writing the geometry exporter.

I don't know how clear I can make it, it's fairly convoluted, but I hope this explains it a bit.

Cheers.

Paolo

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