John Wesley Austin

US Patent:

49106830, Mar 20, 1990

Filed:

Dec 20, 1988

Appl. No.:

7/287390

Inventors:

Thomas G. Bishop - Apex NC
John D. Austin - Chapel Hill NC

Assignee:

Sun Microsystems, Inc. - Mountain View CA

International Classification:

G06F 1562
G06F 314
G09G 102

US Classification:

364518

Abstract:

A user, through the use of an input device, provides signals indicative of x,y and z coordinates to a host central processing unit (CPU). The x,y and z coordinates provided by a user correspond to a desired viewpoint for the display of an object stored in an original data image memory. A graphics CPU is coupled to the host CPU for receipt of the x,y and z coordinates as well as to the original data image memory. The graphics CPU is further coupled to a program memory as well as two display buffers, each of which of comprises a bit map of points on the display. The graphics CPU, executing a rendering program stored in the program memory, renders (writes) the data comprising the object for the viewpoint corresponding to the x,y and z coordinates provided by the user. After a predetermined percentage (N) of data comprising the object have been rendered into the non-displayed buffer, the graphics CPU signals a multiplexor which couples the display to the previously non-displayed display buffer, thereby displaying the predetermined percentage (N) of data which have been rendered. In the event that the user does not provide any new x,y and z coordinates representing a different viewpoint, the graphics CPU continues to render the data comprising the object into the displayed buffer, resulting in the appearance to the user that the object is "sparkling" into view.