RASTERIZATION USING QUADRAANGLE

摘要

PURPOSE: A method for reasterization using a rectangle is provided to reduce the amount of input data and a memory accessing time by counting two triangles sharing one edge as one rectangle. CONSTITUTION: A rectangle with formed two triangles sharing one edge is extracted from an object projected on a screen coordinate(300). An edge function value for four edges of the rectangle and the shared edge of two triangles is calculated if there are coordinate values of vertical axises of two fixed points shared by two triangles between coordinate values of vertical axises of two fixed points which are not shared by two triangles(302,306). A span start point is obtained by edge-walking left edges of the triangles(308). An interpolating process is performed by using the edge function value and the span start point(310).