Hi Andrei - the vertex normals are shading information that's included with the geometry. They are surface normals (surface perpendicular directions) included for each polygon vertex that tells the renderer how to shade the polygon as if it were a smooth surface instead of actually a flat facet.

It's important to have vertex normals go through into your rendering program in order to have the shaded rendered result look the same as the original NURBS surface data. That's because the vertex normals that MoI exports come from the original NURBS surfaces, so they're very accurate and make the polygons get shaded to look the same as the original NURBS model.

If you throw out those vertex normals, then the renderer will calculate new ones for you (you have to have some kind of vertex normals for rendering or else everything would be all flat faceted shaded instead of any smooth shading at all), and the ones that it calculates will come from averaging the polygon face normals that are adjacent to the vertex and it's easy with CAD generated data for there to be large polygons next to small ones and that does not work very well with that sort of averaging process.

So you do not want to throw out the normals like you did in Cinema4D.


For 3D Coat I guess it will depend on which particular process you are using in 3D Coat, if you for example bring in a model into the voxel module there it's not polygon data anymore and new polygons will get created later on. If you are using some other module then maybe there's an option for whether to bring in vertex normals or not.

If you don't get vertex normals to come through then pretty often you will see shading artifacts.



> I know that when I import obj from moi in 3Ds Max it also looks like this.

The Max OBJ importer has a lot of problems especially in slightly older versions of Max, it's best to instead use FBX format for transferring into 3DS Max.

- Michael