METHOD AND DEVICE FOR DIVIDING AND DRAWING POLYGONS

A polygon dividing section divides a polygon which is stored in a polygon graphic data storage area into a number of triangles, with the associated vertex information being distributed among the triangles. In doing this, based on category information which indicates that separated triangles are first, intermediate, or last triangles of the polygon and also based on the edge numbers of the separated triangles, the polygon dividing section selects either edge data or divided edge data, the latter of which indicates an invisible edge, which are stored in the polygon graphic data storage area, and outputs the vertex data of the triangles along with either the edge data or divided edge data to a triangle set graphic data storage area. A triangle drawing section, based on the triangle vertex information stored in the triangle set graphic data storage area, draws the separate triangles on a display device.