Abstract: A computer system is comprised of at least one of a main bus and an attached expansion bus, a CPU connected to the main bus, peripherals connected to one of the main bus or to the expansion buses, a subsystem connected to a bus for receiving control, address and data signals from the CPU comprising a graphics controller, a data compression circuit, a video controller, a memory connected to data input ports of the circuits and controllers via a subsystem bus having a bandwidth sufficient to carry video and graphics display signals, a first arbiter for determining which controller is permitted access the memory, a link bus connecting each of the controllers, and apparatus for providing polling signals to each of the controllers and circuits on the link bus and for receiving acknowledgement signals therefrom, and thereby synchronizing and allowing exchange of control information between the controllers and circuits.

Abstract: A method of drawing moving images on a graphics display comprising (a) receiving data defining an input image in a predetermined resolution, (b) commanding a graphics processor to draw a corresponding image frame on a display having a number of scanning lines which is a multiple m of a number of scanning lines of the input image and a multiple n of a number of pixels in a horizontal line of the input image, (c) drawing successive lines of the input image on a first and on each m.sup.th scanning line of the graphics display, while stretching each pixel on each drawn line over n pixels, (d) copying each drawn line on respective immediately following m-1 lines, and (e) repeating steps (b)-(d) for successive frames of the input image.

Abstract: A computer system is comprised of at least one of a main bus and an attached expansion bus, a CPU connected to the main bus, peripherals connected to one of the main bus or to the expansion buses, a subsystem connected to a bus for receiving control, address and data signals from the CPU comprising a graphics controller, a data compression circuit, a video controller, a memory connected to data input ports of the circuits and controllers via a subsystem bus having a bandwidth sufficient to carry video and graphics display signals, a first arbiter for determining which controller is permitted access the memory, a link bus connecting each of the controllers, and apparatus for providing polling signals to each of the controllers and circuits on the link bus and for receiving acknowledgement signals therefrom, and thereby synchronizing and allowing exchange of control information between the controllers and circuits.

Abstract: A method for drawing lines on a graphics device in such manner in that only those points lying inside a specified rectangular area of the device are drawn. Predetermined digital outcodes are generated for defining the endpoints of the lines and a decision is made whether to draw or not draw the lines based on the relationship of the endpoints with respect to both the specified rectangular area of the device, and a second larger rectangular area of the device.