Arbitrary Area Filling in a Fast Procedure

Abstract

A representation for area filling is described which allows shading of an area that may have both straight lines and circular arc edges and include holes within its boundaries. For efficiency an elimination algorithm which has a waiting line list and a currently active line list is adopted. For calculating intersections, a more time saving method is used. The algorithm and some practical examples are discussed. The main features of the algorithm are execution with high speed and less storage requirement. The program is written both in BASIC and FORTRAN 77 and could be executed on a microcomputer such as APPLE II, IBM-P/C etc. The sample outputs shown in this paper are generated by the APPLE II with high efficiency.