Apparatus and method for managing multiple images in a graphic display

Abstract

A graphic display system with the ability to use mulitiple memory buffers to produce images with a wide range of colors through bit plane encoding or to present independent application displays or to combine display images through the use of lateral bit encoding. When operated in the lateral bit encoded state, application programs can be associated with independent memory buffers or an application can use the separate buffers to create a display with animation or apparent movement. Each memory buffer can be independently associated with the display device or the images contained in the memory buffers can be mixed through the use of hardware or software image mixing to create a composite display. The combined image is use to directly control the display device and does not require the creation of an intermediate frame buffer image. This display system provides the capability for animation or image movement through the designation of one or more planes to contain the objects and the designation of display priority among the memory buffers. The image mixer combines the images according to an established display priority so that portions of the highest priority image are always displayed. The images in the memory buffers may, alternatively, be linked to create a single large image which can be scrolled across the display monitor. A method for image mixing and for displaying objects with apparent motion is provided through the use of the multiple memory buffers and display priority assignment.