| 摘要 |
PURPOSE:To raise the painting-out performance by providing an X and Y direction convex drawing means and a concave polygon drawing means respectively. CONSTITUTION:A polygon drawing control means 1 investigates a convex direction when the polygon to be painted out is concave convex and convex, by an X direction convex deciding means 2 and a Y direction convex deciding means 3, and by the result, instructs the drawing of the polygon to an X direction convex polygon drawing means 4, a Y direction convex polygon drawing means 5 and a concave polygon drawing means 6. The concave polygon drawing means 6 performs the trapezoidal division by the Y coordinates of the polygon, and delivers the trapezoid after division to the Y direction convex polygon drawing means 5. The X direction convex polygon drawing means 4 and the Y direction convex polygon drawing means 5 deliver the starting point and the termination of respective segments to a straight line generating means 7 with the polygon as a segment group perpendicular to an X direction and a Y direction respectively. The straight line generating means 7 generates the address of the segment between respective received starting point and termination and draws it to a frame buffer 8. |
