A system and method for rasterization an image on a display through approximation, wherein the image is decomposed into a plurality of convex polygons, each convex polygon being defined by a plurality of original edges and each original edge being defined by two vertices. The sensor network comprises a common designation network. The middle region 36 may be disposed between and is integral to the first region 32 and the second region 34. The symmetric master key is used to encrypt or decrypt a file encryption key. In the open position, the valve dumps charge flow to the pump case until the supply pressure to the displacement control is inadequate to overcome the centering bias of the displacement control.