CLIPPING CIRCUIT FOR GRAPHIC SYSTEM

摘要

a register means which temporarily stores color data of a clipping region, coordinate data of a figure, coordinate data and mode selection data of clipping region by a graphic controller; a coordinate address generating means which generates coordinate addresses by calculating the coordinate data of the clipping region of the register means; a data read/write means which outputs the color data of the clipping region of the register means by converting the color data in addition to converting the output of the coordinate address generating means into memory addresses when the output of the coordinate address generation and figure coordinate data of the register means coincide; a figure expression control means which express the clipped screen by outputting the data stored by the data read/write means when the output of the coordinate address generating means and the position address of the register means coincide when the mode selection of the register means is a clipping mode.