Constrained Delaunay Triangulations

Scripting C# & .NET
1

I intend to port the CDT portion of CGAL (for non-commercial purposes) to C# unless someone knows of a good existing .NET version of this already (one that you’ve actually used).

Thanks!

Charles

2

Please send me a PM when you have the CDT ported. I am a SQL guy and attempting to roll my own gave me a big headache.

Thanks,
Sammual

3

The Farseer Physics Engine has number of different c# algos for triangulation. Maybe you can find something there.

Here is a link to the CDTDecomposer

http://farseerphysics.codeplex.com/SourceControl/changeset/view/84280#1544123

1 Like
4

Hi there. Any way I could get my hands on that CDT implementation?

5

The Poly2Tri project has a C# port: GitHub - greenm01/poly2tri: Automatically exported from code.google.com/p/poly2tri. I used it previously and found it met my needs.

Edit- It looks like the Farseer physics implements the Poly2Tri code.

6

karl_ have you managed to use the Farseer code for this?
I’ve got a list of Vector3 that defines a polygon (convex AND concave, thus the need for CTD), and I can’t seem to make heads or tails of what to use from their plugin. Project is a 2.5D game, so we’ve got some meshes and we’re not building on top of FarSeer at all.

Thanks for any help with this.

7

I know this is an old topic just wanted to give my 2 cents:

if you have a 3D polygon that you want to triangulate, I’d advice to find a good 2D constraint delaunay solution (poly2tri for example). In poly2tri you can extend their point class, so that you can store the original 3D vector with each 2D vector. The 2D vector is created by using a half way quaternion (to make sure opposite directions don’t match) from your polygons normal towards Vector3.forward and multiply that to the points. The X and Y values are then used to triangulate.