Geometric Calculations

GEOMETRY is a C library which performs certain geometric calculations in 2, 3 and N space.

These calculations include angles, areas, containment, distances, intersections, lengths, and volumes.

Some geometric objects can be described in a variety of ways. For instance, a line has implicit, explicit and parametric representations. The names of routines often will specify the representation used, and there are routines to convert from one representation to another.

Another useful task is the delineation of a standard geometric object. For instance, there is a routine that will return the location of the vertices of an octahedron, and others to produce a series of "equally spaced" points on a circle, ellipse, sphere, or within the interior of a triangle.


The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.


GEOMETRY is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Programs:

DUTCH, a FORTRAN90 library which carries out various computational geometry tasks.

GEOMPACK, a C++ library which computes the Delaunay triangulation and Voronoi diagram of 2D data.

POLYGON_MOMENTS, a C library which computes arbitrary moments of a polygon.

SPHERE_QUAD, a C library which approximates an integral over the surface of the unit sphere by applying a triangulation to the surface;

TABLE_DELAUNAY, a C++ program which reads a file of 2d point coordinates and computes the Delaunay triangulation.

TET_MESH, a C++ library which defines and analyzes tetrahedral meshes.

TETRAHEDRON_PROPERTIES, a C++ program which computes properties of a tetrahedron whose vertex coordinates are read from a file.

TETRAHEDRONS, a dataset directory which contains examples of tetrahedrons;

TRIANGLES, a dataset directory which contains examples of triangles;

TRIANGULATE, a C program which triangulates a (possibly nonconvex) polygon.

TRIANGULATION, a C++ library which defines and analyzes triangulations.

TRIANGULATION_DISPLAY_OPENGL, a C++ program which reads files defining a triangulation and displays an image using Open GL.

TRIANGULATION_TRIANGLE_NEIGHBORS, a C++ program which reads data defining a triangulation, determines the neighboring triangles of each triangle, and writes that information to a file.


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    ISBN: 0123361559,
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Source Code:

Examples and Tests:

List of Routines:

You can go up one level to the C source codes.

Last revised on 14 April 2013.