Ellipse filling graphics method

摘要

An ellipse filling graphics method in which the interior of an ellipse is filled with a single color by writing color data to memory positions designated by addresses corresponding to pixels in the ellipse, comprises the steps of (a) selecting a rectangle which is included in the ellipse, (b) writing color data to memory positions designated by addresses corresponding to pixels inside the selected rectangle, and (c) writing color data to memory positions designated by addresses corresponding to pixels inside the ellipse but outside the selected rectangle. The filling method requires 2({square root over (a2+L +b2+L )}-a) fewer line drawing operations to fill an ellipse, and about 0.8r fewer line drawing operations to fill a circle, compared to a conventional method.