Hi Will re: N-gons - certainly large n-gons that traverse a fairly large area of your model are not good for deformation.

But actually neither are quads or triangles that span a large area of the model - since a polygon modeler usually only deforms the existing vertices of a model, you need to have plenty of vertices throughout the shape, even if it is made up of 100% quads or 100% triangles with no n-gons at all.

That's because a polygon modeler usually only deforms existing vertices in the model. So for example with a twist, only vertices get twisted, not really the polygon surfaces themselves. The polygons remain as straight pieces connected between the vertices.


So it's more of the "span a large area of the model" that is really bad for deformation, not quite so much the "n-gon ness".


But also N-gons do not behave well if they become warped to be significantly non-planar which then makes triangulations of them ambiguous. But they are not necessarily a problem if they are small enough in size so that no individual one is getting warped to a very large degree.


For example see this previous post where PaQ is showing an n-gon model that is being warped inside of Modo with no problems:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2704.17


However, if you do suspect that some individual n-gons are going to get warped to become fairly non-planar then it can be better to avoid them and use "Export: Quads & Triangles" instead so that the polygon structure is all fixed in place from the start.


- Michael