Number of triangles and vertices in usd: how are they calculated, and why the results are different to Blender's result?


I have some questions on how the statistics of the numbers of triangles and vertices in Omniverse. As I am a new user that could not upload multiple images, I put all images into one and you could find Fig.1, Fig. 2, and Fig. 3 in the combine image. Sorry for the inconvenience.

I read the discussion to show the number of triangles and vertices in Omniverse.

I have a 3D model consists of multiple objects from other USD files. I check the statistic in Omniverse and it shows that there are 2.3Billions total visible vertices for all mesh instances; but only 50Million vertices imported and 99.9Million vertices for all unique meshes. As shown in Fig. 1. So, I wonder what is the difference between ‘total visible triangles/vertices for all mesh instances’ and ‘triangles/vertices for all unique meshes’?

If I import the USD file in blender, and check the statistic in blender, then I see different numbers, i.e. 61M Vertices and 92M triangles, as shown in Fig. 2.

As I have triangulated all objects in the USDs, the number of triangles and faces are the same in blender statistics. However, 2.3B vertices give only 98M triangles in Omniverse, which does not make sense, because given that all faces are triangles, 2.3B vertices should have at least 2.3B/3>0.7B triangles.

Then, if I export the scene in blender to another usd file and open it in Omniverse, and check the statistics info, the numbers of ‘vertices imported’ and ‘triangles for all unique meshes’ in Omniverse align with the number in Blender, as shown in Fig. 3.

Therefore, I would like to know how the number of vertices and triangles are counted, and what might be the reason for the different results in Blender and Omniverse.

Thank you for your time!