Abstract: A graphic apparatus of the invention having a clip function includes a clip register storing coordinates of points defining a display designation clip area. The contents of the clip register and an address supplied to a bit map memory are compared by a comparator. Control operation for clipping is performed such that only data falling within the clip area is written in the bit map memory in accordance with the comparison result of the comparator.

Abstract: A memory system is used in a display or printing system for displaying or printing a picture pattern by processing picture data obtained by a function generator. The memory system has memory planes for storing picture data, registers provided in one-to-one relationship with the memory planes for latching the picture data read from the memory planes, and arithmetic logic units provided in one-to-one relationship with the memory planes for performing logical operations on the picture data latched in the registers and obtained by the function generator. The memory system also has an operation mode register storing operation mode data. The arithmetic logic units perform logical operations according to the operation mode data supplied from the operation mode register. The results of the operations are simultaneously written into the respective memory planes.