\cleardoublepage \chapter{Introduction} \input{common_intro} This part of the reference manual covers the basic library. The collection of basic geometric algorithms and data structures currently includes polygons, half-edge data structures, polyhedral surfaces, topological maps, planar maps, arrangements of curves, triangulations, convex hulls, alpha shapes, optimisation algorithms, dynamic point sets for geometric queries, and multidimensional search trees. \input{advanced}