Graphic display scrolling apparatus

摘要

A graphic scrolling apparatus comprising a unit for storing image data; an image display device having a screen for displaying a first predetermined-sized area of the image data stored in the image data storing unit; a buffer memory for temporarily storing a second predetermined-sized area of the image data stored in the image data storing means, the second predetermined-sized area being larger than the first predetermined-sized area; a first depicting unit for retrieving, from the image storing means, at least image data corresponding to a third area of the first predetermined-sized area, which protrudes from the second predetermined-sized area and for depicting the at least image data corresponding to the third area on a fourth area of the second predetermined sized area, which is in the outside of the first predetermined-sized area as the first predetermined-sized area scrolls on the second predetermined-sized area; and an image display controlling unit for controlling the apparatus such that an image is displayed on the screen of the image display device by changing a reading address for the buffer memory to an address of the fourth area and by reading out data of the first predetermined-sized area based on the changed address at the boundary of the first predetermined-sized area when the first predetermined-sized area protrudes from the second predetermined-sized area as the first predetermined-sized area scrolls on the second predetermined-sized area.