Patent Document ID: 5502802
Application ID: 08502466
Patent Status: 1

Claim One:
1. A polygonal image-drawing processor comprising: a device for providing a direction of a linear vector on each of sides constituting a polygon based on information about two end points and side information of the polygon, said direction of the linear vector being selected from eight directions defined in advance; a device for dividing each of the sides constituting the polygon into two groups of right-handed and left-handed sides in accordance with the provided direction of the linear vector and the side information of the polygon; a device for calculating an X address of an intersection point of each of the sides constituting the polygon with a horizontal scanning line by a digital differential analysis at every Y address, said digital differential analysis calculating said X address from the information about two end points and the provided direction of the linear vector on the basis of Bresenham algorithm; a device for controlling the operation of an image memory so as to write X and Y addresses of a left-handed intersection point as an image-drawing starting point of the polygon on the horizontal scanning line and a right-handed intersection point as an image-drawing terminal point of the polygon on the horizontal scanning line respectively in a writing region thereof corresponding to each of the divided two groups, said left-handed intersection point corresponding to an intersection point of the left-handed side with the horizontal scanning line, said right-handed intersection point corresponding to an intersection point of the right-handed side with the horizontal scanning line; and an image-drawing processing device for performing a coloring operation between the respective right-handed and left-handed sides based on the X and Y addresses written in the image memory so as to draw an image.