Automatic Generation of 3D Building Models from Complicated Building Polygons

Abstract

A three-dimensional (3D) urban model is an important information infrastructure that can be utilized in several fields, such as urban planning and game industries. However, enormous time and effort have to be spent to create 3D urban models using 3D modeling software. This paper employs automatic generation of 3D building models through integrating geographic information systems (GIS) and computer graphics. An integrated system is proposed for automatically creating 3D building models from building polygons (building footprints) on a digital map. Because most building polygons’ edges meet at a right angle (orthogonal polygon), the integrated system partitions orthogonal building polygons into a set of rectangles and places rectangular roofs and box-shaped building bodies on these rectangles. In this research, a new scheme for partitioning complicated orthogonal building polygons is proposed. In the digital map, however, not all building polygons are orthogonal. To place parts of a building properly, in either orthogonal or nonorthogonal polygons, the proposed system places parts of a building, such as windows along the inner contour, which is set back from the original building polygon by straight skeleton computation. For a multiple-bounded polygon (a building polygon bounded by outer polygons), a new scheme is also presented for creating a complicated building-shape model or a multilayer building.