Antialiased imaging with improved pixel supersampling

Claim 2

A raster system for generating antialiased display data within an image processing system, wherein said image processing system includes a scan conversion subsystem for generating pixel packets which indicate polygon coverage within a pixel, wherein the pixel comprises a plurality of supersamples, comprising: a first image memory for storing a first color value; a second image memory for storing a second color value; means for storing pixel memory that indicates a current state of the pixel, wherein said pixel memory comprises a region mask having a plurality of fields, each field being associated with a unique one of said plurality of supersamples, wherein when the color value of each supersample is either said first color value or said second color value, then each field associated with a supersample having said first color value stores an identifier that identifies said first image memory, and each field associated with a supersample having said second color value stores an identifier that identifies said second image memory; and an image processor, coupled to receive a pixel packet from the scan conversion subsystem, and further coupled to update said pixel memory, wherein said image processor generates antialiased display data based on said pixel memory, and wherein said image processor includes, means for determining a new pixel state based on said current state of the pixel and said pixel packet, and means for updating said pixel memory based on said new pixel state.

Claim 3

The raster system of claim 1, wherein said pixel memory further comprises a mode identifier, wherein said region mask and said mode identifier together indicate said current state of the pixel.

Claim 4

The raster system of claim 2, wherein said pixel packet comprises a supersample coverage mask.

Claim 5

The raster system of claim 3, wherein said pixel memory further comprises a plurality of supersample memories, each of said supersample memories including a color value field that stores a color value.

Claim 6

The raster system of claim 4, wherein said means for updating updates said color value field of each supersample memory only when the pixel is associated with more than two colors.

Claim 7

The raster system of claim 5, wherein each of said plurality of supersample memories further includes a Z-value field that stores a Z-value, and said pixel packet further comprises at least one Z-value.

Claim 8

The raster system of claim 6, wherein said means for updating performs Z-buffering on a supersample-by-supersample basis.

Claim 9

The raster system of claim 1, wherein said pixel memory indicates a current pixel state according to a rendering mode.

Claim 10

The raster system of claim 8, wherein said rendering mode comprises a blended polygon rendering mode and a non-blended polygon rendering mode.

Claim 11

The raster system of claim 1, wherein each of said fields of said region mask consists of a single binary digit that can hold one of two values: 0 or 1.

Claim 14

The method of claim 11, wherein said pixel memory further comprises a mode identifier, wherein said region mask and said mode identifier together indicate said current state of said pixel.

Claim 15

The method of claim 12, wherein said pixel packet comprises a supersample coverage mask.

Claim 16

The method of claim 13, wherein said pixel memory further comprises a plurality of supersample memories, each of said supersample memories including a color value field that stores a color value.

Claim 17

The method of claim 14, wherein said color value field of each of said supersample memories is updated in step (5) only when said pixel is associated with more than two colors.

Claim 18

The method of claim 15, wherein each of said plurality of supersample memories further includes a Z-value field that stores a Z-value, and said pixel packet further comprises at least one Z-value.

Claim 19

The method of claim 16, wherein said step of updating comprises Z-buffering on a supersample-by-supersample basis.

Claim 20

The method of claim 11, wherein said second color value equals said first color value.

Claim 21

The method of claim 11, wherein said second color value is a function of not only said first color value, but also the color value stored in said image memory prior to said second color value being stored in said image memory.

Claim 22

A computer graphics system comprising: a host processor, wherein said host processor generates world coordinate based graphical data; a geometry subsystem, coupled to receive said world coordinate based graphical data, wherein said geometry subsystem converts said world coordinate based graphical data to screen space coordinate data; a scan conversion subsystem, coupled to receive said screen space coordinate data, wherein said scan conversion subsystem generates pixel packets based on said screen space coordinate data; a raster system including, a first image memory for storing a first color value; a second image memory for storing a second color value; means for storing a pixel memory corresponding to a pixel comprising a plurality of supersamples, said pixel memory indicating a current state of said pixel and comprising a region mask having a plurality of fields, each field being associated with a unique one of said supersamples, wherein when the color value of each supersample is either said first color value or said second color value, then each field associated with a supersample having said first color value stores an identifier that identifies said first image memory, and each field associated with a supersample having said second color value stores an identifier that identifies said second image memory, and an image processor, coupled to receive a pixel packet from the scan conversion subsystem, and further coupled to update said pixel memory, wherein said image processor generates antialiased display data based on said pixel memory, and wherein said image processor includes, means for determining a new pixel state based on said current pixel state and said pixel packet, and means for updating said pixel memory based on said new pixel state; and a display subsystem, coupled to receive said antialiased display data.

Claim 23

A computer graphics system comprising: a host processor, wherein said host processor generates world coordinate based graphical data; a geometry subsystem, coupled to receive said world coordinate based graphical data, wherein said geometry subsystem converts said world coordinate based graphical data to screen space coordinate data; a scan conversion subsystem, coupled to receive said screen space coordinate data, wherein said scan conversion subsystem generates pixel packets based on said screen space coordinate data; a raster system including, a first image memory for storing a first color value; a second image memory for storing a second color value; means for storing a pixel memory corresponding to a pixel comprising a plurality of supersamples, said pixel memory indicating a current state of said pixel and comprising a region mask having a plurality of fields, each field being associated with a unique one of said supersamples, wherein when the color value of each supersample is either said first color value or said second color value, then each field associated with a supersample having said first color value stores an identifier that identifies said first image memory, and each field associated with a supersample having said second color value stores an identifier that identifies said second image memory, and an image processor, coupled to receive a pixel packet from the scan conversion subsystem, and further coupled to update said pixel memory, wherein said image processor generates antialiased display data based on said pixel memory, and wherein said image processor includes, means for determining a new pixel state based on said current pixel state and said pixel packet, and means for updating said pixel memory based on said new pixel state; and a display subsystem, coupled to receive said antialiased display data.

Claim 26

The method of claim 21, further comprising the step of associating each of said plurality of supersamples with a supersample memory comprising a color field that stores a color value.

Claim 27

The method of claim 22, further comprising the step of storing a color value in each color field only if more than two colors are associated with said pixel.

Claim 28

The method of claim 21, wherein each of said fields consists of a single binary digit that can hold one of two values: 0 or 1.

Claim 29

The method of claim 21, further comprising the step of initializing a mode identifier, wherein said mode identifier together with said region mask indicates said state of said pixel.