PLOTTING DATA GENERATOR FOR CIRCULAR ARC BY POLYGONAL APPROXIMATION

摘要

PURPOSE:To perform polygonal approximation conversion on only a part displayed on a screen actually out of set circular arcs in the plotting data conversion of a circular arc by polygonal approximation. CONSTITUTION:The polygonal approximation conversion on only a display part is performed by finding the intersection of the set circular arc with each side of a display area by an intersection coordinate calculation means 2, calculating the start angle and end angle of a circular arc part in the display area by an intersection angle calculation means 4, and setting those angles on a conversion means 10 by a start angle setting means 8 and an end angle setting means 9. When the start point coordinates of the set circular arc exist in the display area. the start angle is set as the one of the circular arc as it is, and when the end point coordinates exist in the display area, the end angle is set as the end angle of a display circular arc.