DETERMINING A COVERAGE MASK FOR A PIXEL

摘要

The invention relates to a method, a device, a system and a software program product for determining for a pixel a coverage mask reflecting an orientation and possibly a distance from the pixel center of an original edge vector. The pixel is to be employed for displaying at least a part of a geometric primitive on a display, and the original edge vector represents an oriented edge of the geometric primitive. In order to reduce the required storage space for coverage masks, it is proposed that the method comprises as a first step determining one of four quadrants of a Cartesian coordinate system to which the original edge vector belongs due to its orientation. The original edge vector is then transposed into a predetermined one of the four quadrants. Next, a stored coverage mask is fetched, which is associated at least indirectly to the transposed edge vector. Finally, the fetched coverage mask is transformed to the quadrant to which the original edge vector belongs.