Hi stefan,

MoI only saves pure NURBS objects to 3DM files, it does not write out any render mesh data in addition to the NURBS objects since those often times bloat the file size up by many times in size.

The reason why Rhino was designed to store render meshes is because it has a very slow meshing mechanism. It was necessary to store them in the file to avoid the slow recalculation time to get a shaded display.

That problem is solved in MoI by having a very fast display mesh generation mechanism - having a very fast display tessellator enables MoI to create display meshes on demand when loading a file instead of having to store all that additional data in the files. This results in smaller files being saved which is a nice benefit.

That fast display mesher also helps out at model time in MoI a lot as well, since when you edit a model the display mesh may need to be recalculated anyway in response to changes in the model.


> 1) it seems moi does not save any render meshes into the 3dm
> file( or does it differently?)

It never saves render mesh data as part of a NURBS object, when it loads in a 3DM file it just creates the render meshes as needed by tessellating them.


> 2) i find no way to tessellate a geometry in writing a 3dm file.

Yes, that's correct - but the same thing applies to Rhino as well - there isn't any mechanism in Rhino to save a "meshed 3DM" file at save time by picking it as a file type off of the file type list.

The reason why is it could easily lead to confusion having different kinds of 3DM files that are written but with completely different types of objects in them.

3DM is intended to be MoI's primary file format, so it wants to write out the full NURBS objects to its primary file format and not possibly confuse someone by thinking they are saving their true model data to 3DM when it actually turned out that they were writing only tessellated data (which MoI cannot read back in again) to their file, basically losing their work.


> so my question would be, is it possible to add an option to
> tessellate the file on export also to 3dm? or is it possible to add a
> command to mesh objects in MOI itself,as it can be done in rhino?

Possibly in the future, but there is not currently any way set up to do this.

MoI is not currently focused on working with mesh data at model time, so that's why there is not any separate "Mesh" command for turning objects into a mesh but keeping it in the model instead of writing it out to a mesh file.


But what is it that you are trying to gain by reading the mesh data out of a 3DM file, instead of reading the same mesh data out of a more polygon oriented type of file like an OBJ file?

With the RipTide importer, Cinema4D is able to import material information from OBJ files.... Is there something that you're trying to do that is not covered well by just loading an OBJ file into Cinema4D instead ?

- Michael