POLYGON PARTITION AND SHAPE RECTIFICATION FOR AUTOMATIC GENERATION OF 3D BUILDING MODEL

A 3D urban model is important in urban planning and game industries. However, creating these 3D models are labor-intensive. In order to automate laborious steps, a GIS (Geographic Information System) and CG (Computer Graphics) integrated system is proposed for automatically generating 3D building models, based on building polygons on a digital map. These polygons are usually orthogonal. A complicated orthogonal polygon can be partitioned into a set of rectangles. The proposed integrated system partitions orthogonal building polygons into a set of rectangles and places rectangular roofs and box-shaped building bodies on these rectangles. Since technicians are drawing these polygons manually with digitizers, depending on aerial photos, not all building polygons are precisely orthogonal. But, when placing a set of boxes as building bodies for creating the buildings, there may be gaps or overlaps between these boxes if building polygons are not precisely orthogonal. In this paper, the new methodology is proposed for partitioning and rectifying building polygons.