Patent ID: 7551173

Claim:
A method of rendering a graphic object by a computer that uses a coordinate of an edge crossing of a scan line with at least one edge of the graphic object, said method comprising the steps of: providing a first point and a second point on the edge of the graphic object; determining an integer part and a fractional part of a ratio of a horizontal difference between the first point and the second point of the edge to a vertical difference between the first point and the second point of the edge; utilizing the fractional part of the ratio to determine a fractional part of the coordinate at an intermediate scan line between the first point and the second point, wherein a rounded version of the coordinate at the intermediate scan line is determined according to a rounding rule utilizing integer arithmetic excluding integer division; utilizing at least the integer part of the ratio to determine an integer part of the coordinate at the intermediate scan line; and storing the integer part and the fractional part of the coordinate of the edge crossing in an edge record configured within a computer memory associated with the computer, wherein the integer part and the fractional part of the coordinate stored in the edge record are used by the computer to render the graphic object, wherein the rounded version of said coordinate is determined based on (a) an accumulated fractional part of said coordinate and (b) a predetermined value dependent on said rounding rule.