And then with a different approach of trying to save both mesh and surface data within the same file (rather than having a special "Mesh 3DM" type export as I was describing above) has the problem that Steve mentions - file sizes would be greatly increased with information that's not actually used by MoI at all since it creates display meshes as needed dynamically when files are loaded.

Rhino has a method where it stores display mesh information in the 3DM file so that it doesn't have to recalculate it later, but the reason why it does this is because it has an extremely slow meshing mechanism.

Since MoI has a very fast meshing mechanism it eliminated the need to store all that large amount of display data in the file.

Some programs (like that iPad viewer for example, and some import plug-ins for some other programs) have started to read only that display mesh data out of 3DM files, but that's not a very good approach because that data is not even necessarily present in files that Rhino writes - it only will only be present from Rhino saved files if you've done a render in Rhino first before saving. It's basically a cache of some of Rhino's display information.

- Michael