Automatic Generation of 3-D Building Models Based on a Digital Map

Based on building polygons (building footprints) on a digital map, we are proposing a GIS (Geographic Information System) and CG integrated system to generate 3-D building models automatically. Most building polygons‟ edges meet at right angles (orthogonal polygon). A complicated orthogonal polygon can be partitioned into a set of rectangles. In order to partition an orthogonal polygon, we proposed a useful polygon expression and a partitioning scheme in deciding from which vertex a dividing line (DL) is drawn. After partitioning, the integrated system will place rectangular roofs and box-shaped building bodies on these rectangles. In this paper, we propose a new scheme for partitioning building polygons and for creating a complicated shape of building models based on the building polygons bounded by outer polygons (multiple bounded polygon).