Re: how to group a set of triangles based on its original geometry model

jeff wrote:


I am trying to identify and group a set of triangle based its
corresponding geometry model.

I think you're trying to tackle this from the wrong end. It would be far easier not to throw away that information during triangle decomposition of the original model data.

Let's say I have 3 models, a cylinder, a cone and a cube. All these 3
models undergone surface meshing process and generate a common list of
the triangles.

So why did you throw away the information which triangle came from which primitive?

I need to isolate the triangles into a number of group(in this case it
would be 3).

That's generally impossible. How is an algorithm supposed to know whether you wanted a cylinder or a wall plus two polygons that just happen to share two polygonal edges?
.