Computational Geometry has some of the algorithms implemented in c#. It includes algorithms for finding relative orientations of points, line segments and vectors among others. This project is a result of the following blog posts Algorithms in Computational Geometry – Part 1 & Part 2. Please read them before downloading this.
Download Computational Geometry source code
The solution contains a CGLibrary project which encapsulates all the algorithms required for Computational Geometry problems. It also has a windows app to showcase how we can use the library and a comprehensive test suite. It uses ZedGraph an open source .NET chart control library for plotting points and lines.