Patent ID: 6313839
Filing Date: 2001-11-06
Classification: G06T

Abstract:
An apparatus for performing Z depth comparison tests in a computer graphics display system, the apparatus comprising:a frame buffer memory controller receiving primitives relating to an image to be displayed on a display monitor of the computer graphics display system, the primitives having a Z value associated with each vertex of the primitive; anda frame buffer memory device in communication with the controller, the memory device storing Z values of primitives to be displayed on the display monitor, each received Z value being associated with a region of Z values in the memory device, the memory device storing maximum and minimum Z values for regions of primitives, the maximum Z value corresponding to a largest Z value of a region of Z values, the minimum Z value corresponding to a smallest Z value of all of the Z values of the region, the controller comparing each Z value received in the controller with the maximum Z value for the corresponding region to determine whether the primitive associated with the received Z value is occluded.