G# - Computational geometry for .NET

G# is perfectly suitable for Digital Terrain Modelling (DTM):

its fast O(n·log(n)) randomized incremental algorithm enables the extremely fast triangulation of very large point sets. At the same time, G# is very robust due to the implementation of exact arithmetic. Click here to see an example.

G# can also triangulate edge constraints (breaklines), holes, islands and arbitrary shaped bounds by both inserting ("conforming Delaunay") and not inserting ("constraint Delaunay") additional triangulation points. Click here to see an example.

Digital Terrain Modelling requires editing triangulated surfaces: G# provides methods to compute contour and profile lines, to project points and lines onto and to to slice such surfaces, to import and export them and lots of other DTM features.

Click here for more details on the implemented triangulation algorithm, valid input data and restrictions.

Given a set of completely unordered wireframe edges, G# can reconstruct a surface consisting of triangular and quadrialteral faces in O(n·log(n)) time.

Click here to see a performance chart.

A 2d convex hull is the shortest path enclosing a planar set of points. G# computes the convex hull of n planar points in O(n·log(n)) time. Click here to see an example.

A 3d convex hull encloses a set of 3d points with a minimal surface area. G# computes the convex hull of n 3d points in O(n·log(n)) time. Click here to see an example. Click here to see a performance chart.

For ultimate robustness, G# uses exact arithmetic.

Compute mass moments of inertia and the pricipal axes of the mass moments of inertia of 3d convex hulls! Use these methods to compute a bounding box along the principal axes of a 3d convex hull.

Click here to see how this bounding box can be used as a fast approximate solution for a 3d container loading problem.

G# uses the rotating caliper technique to compute the minimum area and minimum perimeter enclosing rectangles of a 2d point set in O(n·log(n)) time.

Click here to see an example.

Compute the smallest enclosing circle of a planar point set in expected O(n) time!

Click here to see an example.

Click here to see a performance chart.

A polyline is a list of sorted edges where the end point of each edge is the start point of the next edge. G# converts hundreds of thousands of unordered lines in space into 3d polylines. Ultra fast!

A closed planar polyline is regarded as a polygon. G# provides fast exact arithmetic point-in-polygon and polygon-in-polygon tests.