Re: [Algorithms] Edge collapse based simplification problem

[Joe A. <jo...@li...>]

Hi Peter,
> The standard way people solve this (as far as I know) is to just check for
> faces flipping after the collapse (and not allowing it if this happens.)
How exactly do I test for flipping after the collapse?

> (I think the topological test might just be if the intersection of the 1 rings
> of two vertices on the edge that is being collapsed contains vertices that
> aren't on the face(s) that are going to be removed after the collapse the
> resulting mesh would be non-manifold.  I believe hugues discusses this in his
> thesis and Edelsbruner (sp?) has papers that discuss this as well...
Ive not been able to find these papers, hoppes thesis seems to be availible
only as ppt presentation.

> So 
> basically the intersection of the 1 rings should have 4 vertices (3 if it's a
> boundary edge.)
Ah that sounds like a much simpler test, thanks.

Are you sure that the intersection should be 4 vertices for non boundary
edges?
When I draw it on paper the 1ring intersection seems to be 3 for
non-boundary and 2 for boundary edges when the edge will become
non-manifold.

Joe ANte