# N-gon triangulation

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(No answers from the .NET forum, trying here) I need to extrude paths to 3D models, and thought I would find zillions of public domain implementations on the web, but they seem really scarce. One implementation that looks good is Jonathan Shewchuk's Triangle ( http://www.cs.cmu.edu/~quake/triangle.html ). I need it as a .NET library, and his C implementation is very hard to read for me though, so I'm looking for a version in a more modern language (Java, C# etc, something with less pointer ops). Anything around? I could do with other algoritms as well, but I like that his solution produces no sharp angles. Thanks!

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For clarification: Your subject is "N-gon triangulation", which usually means that you start with an n-sided polygon and you want to triangulate it. The text of your post mentions Shewchuk's code, which is more along the lines of constructing a triangulation for an unordered set of points. The basic algorithm in that code uses Delaunay triangulation. It also allows for constrained triangulation, which could be used to triangulate a polygon by requiring that the polygon edges be part of the triangulation, but that would be overkill. Shewchuk's code also allows manipulation of a triangle mesh to try to make it look "better" (you can patch into the system to control this).

Which of these types of problem are you trying to solve? It is not clear to me how "extrude paths to 3D models" fits into either scheme. Any details?

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I never really dealt with geometry before so I'm not familiar with terminology and concepts, sorry for the confusing question. The basic problem I need to solve is to extrude a font to a set of 3D models. Triangle looks like it's a nice toolkit for several related areas.

I think I would need constrained Delaunay triangulation (for fewest possible triangles), but constrained conforming Delaunay triangulation seems like it would be better for further processing of the mesh.

Thanks for pointing my vagueness, now that I've looked further into the terminology I'll have a better chance of finding some code! Would you happen to have any good links?

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Here's a page that describes how to turn a font into 3D geometry using C++, DirectX and OpenGL: Triangulating and Extruding Arbitrary Polygons. I have used the Tao OpenGL bindings with Managed DirectX and C# to triangulate polygons and it works fine, there's very little conversion necessary. Let me know if you have any troubles.

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Thanks, but I need yo use it in a sandbox XBAP/XAML setting, so P/Invoke for accessing OpenGL's GLUtesselator isn't going to work...

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