Hi FlashFire,

> I wanted to point out that sometimes poly artifacts can show
> up even when C4D is used to render a moi model imported
> with normals.

That shouldn't be the case - do you have an example model you can post? Please post the actual model file though and not just a screenshot.

Also your last screenshots did not show what the rendering looked like in Cinema4D - with the proper vertex normals coming over, models such as you show there should not have any artifacts in them at all, they will look the same as the original NURBS object despite that kind of topology.


> Many points have to be manually welded/cleaned up.

This may mean that you have not prepared the model properly - make sure to join surfaces that are sitting next to one another so they will get a watertight mesh created for them.

If you have surfaces that are not joined to one another but are just sitting next to one another as independent objects, that will make them get meshed independently and they can have get separate vertex structures created for them in that case.

Also you may just need to create a bit higher density mesh to get a smoother looking result.

Don't forget that polygon models are not actually smooth things, they're made up of little facets and the smoothing is a kind of visual trick that's done by using vertex normals. If you have a small number of facets, that can stop the illusion of smoothness from working very well.


> Look at the polys to the left of the words output: and display:

Those should not have any problems in the actual render in Cinema4D with proper vertex normals on them.

Have you possibly turned off the import of vertex normals into Cinema4D?

Also I would recommend using n-gons - Cinema4D has very good support for n-gons and while it is possible for there to be n-gon triangulation problems in Cinema4D, it is quite rare, so I would recommend using n-gon output for regular use, and only switch to Quads & Triangles output for some special purpose when you have actually identified a problem rather than just defaulting to that.


It would really help though if you could post a model that you're having problems with though instead of just screenshots.

I think some of your prior polygon modeling experience may be working against you - if you built a regular polygon model with slivery polygons like that, that could indeed cause artifacts because it's hard for the smoother to make good vertex normals cooked up from scratch on polygons like that. So you seem to be just assuming you're going to have problems because of that topology. (it sure seems like you're just assuming that anyway since you did not show any rendering result). But when you have vertex normals coming in from the original NURBS surface, that is a completely different things and won't have the same kind of artifacts.

It's important though to make sure the vertex normals are being preserved though, that's the key thing that makes the render of topology like that look totally smooth and keep the same appearance as the original NURBS model.

Another general problem you may be running into kind of related to your past sub-d modeling experience is that you may be producing too low polygon of a result out of MoI if you're seeing artifacts. Remember that you're not going to be relying on sub-d smoothing to be applied to smooth out the model further, so you should not try to make as rough of an initial cage as you would if you were doing a sub-d model.

If you make a low poly model you can get various kinds of artifacts that are just part of being low poly. The solution to that is to increase polygon density.

- Michael