Patent ID: 8547395

Claim:
A method of processing data in a computer-implemented graphics pipeline comprising a rasterizer and a shader, said method comprising: identifying a first pixel that is at least partially covered by a primitive; accessing, at said rasterizer, real sample coverage information for a real sample location located within said first pixel, said real sample coverage information indicating whether said real sample location is covered by said primitive; determining virtual sample coverage information for a plurality of virtual sample locations located within said first pixel, wherein said virtual sample coverage information is based on said real sample coverage information and identifies which of said virtual sample locations assume a pixel attribute value associated with said real sample location and which of said virtual sample locations assume a pixel attribute value associated with a real sample location associated with a pixel that adjoins said first pixel, wherein said virtual sample coverage information comprises a first value to indicate a virtual sample location within said first pixel is covered by said primitive only if both said virtual sample location and said real sample location are covered by said primitive, said virtual sample coverage information comprising a second value to indicate said virtual sample location is deemed to be uncovered by said primitive if either one or both of said real sample location and said virtual sample location are not covered by said primitive; changing, at said rasterizer, said virtual sample coverage information to account for a new primitive that also covers said first pixel at least in part, producing rasterized virtual sample coverage information for said first pixel; and if said shader will be killing said first pixel based on information indicating said first pixel will not be rendered in a graphical display, then writing said rasterized virtual sample coverage information from said rasterizer to said shader using a first write path that bypasses a framebuffer, and otherwise sending said rasterized virtual sample coverage information from said rasterizer to said framebuffer using a second write path that bypasses said shader without sending said rasterized virtual sample coverage information to said shader.