matGeom is a geometry library for Matlab in 2D and 3D. You are able to create, transform, manipulate and display geometric primitives (points, lines, polygons, and planes). Typical operations involve creation of shapes, computation of intersections, transforming shape coordinates, combining shapes to create new ones. You can have a look at the demo pages to have an overview of the syntax and possibilities. The library is composed of several packages like geom2d for various computations in the plane, polygons2d for operation involving poly lines, polygons, or point sets, polynomialCurves2d for manipulation and fitting of smooth curves, and meshes3d for manipulating polyhedral meshes in 3D.