Method and system for providing texture using a selected portion of a texture map

Claim 2

A computer graphics raster subsystem for providing texture from a texture pattern to an image to be rendered for display in real-time comprising: texture memory for storing a select portion of a texture map representation of said texture pattern, said select texture map portion containing texture data at multiple levels of detail to substantially cover said image in a display view; texture mapping means for mapping texture data from said select texture map portion stored in said texture memory to corresponding pixel data defining said display image; and clip-map updating means for updating edges of said select texture map portion to track changes in the location of the eyepoint in real-time.

Claim 3

The system of claim 1, wherein said texture memory stores said texture data in a two-dimensional or a three-dimensional texel array.

Claim 4

A computer graphics processing system for providing texture from a texture pattern in a display image, comprising: first texture memory for storing a texture map, said texture map having multiple level of detail maps for storing texels representing the texture pattern filtered at successively coarser resolutions; clip-map selecting means for selecting a clip-map within said texture map, said clip-map consisting of a set of tiles corresponding to regions of said level of detail maps substantially covering the display image; second texture memory for storing said clip-map; texture processor means for retrieving texels from said clip-map which map to pixel data forming the display image; and clip-map updating means for updating texels at edges of said tiles stored in said second texture memory to track changes in the location of an eyepoint.

Claim 5

A computer graphics processing system for providing texture from a texture pattern in a display image, comprising: first texture memory for storing a texture map, said texture map having multiple level of detail maps for storing texels representing the texture pattern filtered at successively coarser resolutions; clip-map selecting means for selecting a clip-map within said texture map, said clip-map consisting of a set of tiles corresponding to regions of said level of detail maps substantially covering the display image; second texture memory for storing said clip-map; texture processor means for retrieving texels from said clip-map which map to pixel data forming the display image; and clip-map updating means for updating texels at edges of said tiles stored in said second texture memory to track changes in the location of an eyepoint.

Claim 6

The computer graphics system of claim 3, wherein said first and second texture memory constitute a hierarchial memory arrangement relative to said texture processor means, said texture processor means accesses texels stored in said second texture memory faster than said first texture memory.

Claim 7

The computer graphics system of claim 3, wherein: said first texture memory comprises a mass storage device, and said second texture memory comprises at least one of a static random access memory (SRAM) device and a dynamic random access memory (DRAM) device.

Claim 8

The computer graphics system of claim 3, wherein said clip-map selecting means determines the area of the texture pattern covered by each tile based on the location of an eyepoint of the display image.

Claim 9

The computer graphics system of claim 3, wherein said clip-map updating means updates texels at edges of said tiles stored in said second texture memory to track changes in the location of a new eyepoint for a new display image.

Claim 10

The computer graphics system of claim 7, wherein said clip-map updating means discards texels from said second texture memory and loads texels from said first texture memory into said second texture memory; said texels being discarded from at least one tile edge located furthest from said new eyepoint and said texels being loaded into at least one tile edge located closer to said new eyepoint.

Claim 11

The computer graphics subsystem of claim 3, wherein, said texture processor means further retrieves coarser substitute texels from said clip-map.

Claim 12

The computer graphics system of claim 3, wherein textured display images are output for display in real-time.

Claim 13

The computer graphics system of claim 3, wherein said clip-map contains over 99% less texels than said texture map.

Claim 14

The computer graphics system of claim 3, wherein said texture processor means comprises: a texture generator; and a texture memory manager coupled between said texture generator and said second texture memory; wherein said texture generator includes a texture coordinate generator for generating texel coordinates for each pixel and a LOD generator for generating a LOD value for each pixel, said LOD value identifies the tile which covers the pixel and has texel dimensions closest in size to the pixel, said texel coordinates and LOD value being output for each pixel to said texture memory manager; and wherein said texture memory manager retrieves texels from said clip-map for combining with said pixels to form a textured display image.

Claim 15

The system of claim 3, wherein said second texture memory stores texels in said clip-map in a two-dimensional or a three-dimensional texel array.

Claim 16

A computer graphics processing system for providing texture from a texture pattern in a display image, comprising: first texture memory for storing a texture map said texture map having multiple level of detail maps for storing texels representing the texture pattern filtered at successively coarser resolutions; clip-map selecting means for selecting a clip-map within said texture map, said clip-map consisting of a set of tiles corresponding to regions of said level of detail maps substantially covering the display image; second texture memory for storing said clip-map; and texture processor means for retrieving texels from said clip-map which map to pixel data forming the display image, wherein said texture processor means comprises: texture coordinate generator for generating at least one texture coordinate identifying where a pixel in the display image maps to the texture pattern, LOD generator for generating a LOD value, and a memory controller for retrieving at least one texel from said clip-map stored in said second texture memory based on said at least one texture coordinate and said LOD value, wherein, said LOD generator includes: LOD identifying means for identifying an appropriate level of detail representing the level of detail map amongst said multiple level of detail maps where texel dimension is closest in size to said pixel, texel determining means for determining whether a texel at said at least one texture coordinate is included in a first tile at said appropriate level of detail, said LOD value being set to said appropriate level of detail when said texel is included in said first tile, and substitute texel determining means for determining a substitute texel in a second tile which includes said at least one texture coordinate, said LOD value being set to the level of detail of said second tile.

Claim 17

A computer graphics processing system for providing texture from a texture pattern in a display image, comprising: first texture memory for storing a texture map said texture map having multiple level of detail maps for storing texels representing the texture pattern filtered at successively coarser resolutions; clip-map selecting means for selecting a clip-map within said texture map, said clip-map consisting of a set of tiles corresponding to regions of said level of detail maps substantially covering the display image; second texture memory for storing said clip-map; and texture processor means for retrieving texels from said clip-map which map to pixel data forming the display image, wherein said texture processor means comprises: texture coordinate generator for generating at least one texture coordinate identifying where a pixel in the display image maps to the texture pattern, LOD generator for generating a LOD value, and a memory controller for retrieving at least one texel from said clip-map stored in said second texture memory based on said at least one texture coordinate and said LOD value, wherein, said LOD generator includes: LOD identifying means for identifying an appropriate level of detail representing the level of detail map amongst said multiple level of detail maps where texel dimension is closest in size to said pixel, texel determining means for determining whether a texel at said at least one texture coordinate is included in a first tile at said appropriate level of detail, said LOD value being set to said appropriate level of detail when said texel is included in said first tile, and substitute texel determining means for determining a substitute texel in a second tile which includes said at least one texture coordinate, said LOD value being set to the level of detail of said second tile.

Claim 18

A computer graphics processing system for providing texture from a texture pattern in a display image, comprising: first texture memory for storing a texture map, said texture map having multiple level of detail maps for storing texels representing the texture pattern filtered at successively coarser resolutions; clip-map electing means for selecting a clip-map within said texture map, said clip-map consisting of a set of tiles corresponding to regions of said level of detail maps substantially covering the display image; second texture memory for storing said clip-map; and texture processor means for retrieving texels from said clip-map which map to pixel data forming the display image, wherein said set of tiles comprises a cubical part and a pyramidal part; said one or more tiles in said cubical part comprising one or more arrays of texels, respectively, within said regions of said level of detail maps, and said one or more tiles in said pyramidal part comprising one or more arrays of texels, respectively, said one or more arrays texels in said pyramidal part consisting of said level of detail maps which are equal to or smaller than said one or more tiles in said cubical part.

Claim 19

A computer graphics processing system for providing texture from a texture pattern in a display image, comprising: first texture memory for storing a texture map, said texture map having multiple level of detail maps for storing texels representing the texture pattern filtered at successively coarser resolutions; clip-map electing means for selecting a clip-map within said texture map, said clip-map consisting of a set of tiles corresponding to regions of said level of detail maps substantially covering the display image; second texture memory for storing said clip-map; and texture processor means for retrieving texels from said clip-map which map to pixel data forming the display image, wherein said set of tiles comprises a cubical part and a pyramidal part; said one or more tiles in said cubical part comprising one or more arrays of texels, respectively, within said regions of said level of detail maps, and said one or more tiles in said pyramidal part comprising one or more arrays of texels, respectively, said one or more arrays texels in said pyramidal part consisting of said level of detail maps which are equal to or smaller than said one or more tiles in said cubical part.

Claim 22

The method of claim 16, wherein said updating step updates said clip-map to track a change in said eyepoint location for a new display image.

Claim 25

The method of claim 16, wherein said updating step update texels at edges of said tiles stored in said second texture memory to track a change to a new eyepoint location for a new display image.

Claim 26

The method of claim 19, wherein said updating step includes the steps of: discarding texels from an edge of a tile located furthest from said new eyepoint location; and loading texels from said first texture memory to said second texture memory, said texels being loaded next to an edge of a tile closer to the new eyepoint location wherein the number of texels loaded equals the number of texels discarded to maintain the size of said tile constant.

Claim 27

The method of claim 16, further comprising the step of retrieving coarser substitute texels from said clip-map stored in said second texture memory.

Claim 28

The method of claim 16, wherein said storing step stores texels in said clip-map in a two-dimensional or a three-dimensional texel array.

Claim 31

A texture processor for mapping texels from a clip-map to corresponding pixels, wherein the clip-map consists a set of tiles representing a selected portion of a texture MIP-map which substantially covers the pixels, said texture processor comprising: a texture memory storing the clip-map; a texture generator; and a texture memory manager coupled between said texture generator and said texture memory, wherein said texture generator includes a texture coordinate generator for generating texel coordinates for each pixel and a LOD generator for generating a LOD value for each pixel, said LOD value identifies the tile which covers the pixel and has texel dimensions closest in size to the pixel, said texel coordinates and LOD value being output for each pixel to said texture memory manager; and said texture memory manager retrieves texels from the clip-map stored in said texture memory for combining with said pixels to form a textured display image.

Claim 32

A texture processor for mapping texels from a clip-map to corresponding pixels, wherein the clip-map consists a set of tiles representing a selected portion of a texture MIP-map which substantially covers the pixels, said texture processor comprising: a texture memory storing the clip-map; a texture generator; and a texture memory manager coupled between said texture generator and said texture memory, wherein said texture generator includes a texture coordinate generator for generating texel coordinates for each pixel and a LOD generator for generating a LOD value for each pixel, said LOD value identifies the tile which covers the pixel and has texel dimensions closest in size to the pixel, said texel coordinates and LOD value being output for each pixel to said texture memory manager; and said texture memory manager retrieves texels from the clip-map stored in said texture memory for combining with said pixels to form a textured display image.

Claim 33

The texture processor of claim 24, wherein said texture memory stores said texels in two-dimensional or three-dimensional texel arrays.

Claim 34

The texture processor of claim 24, wherein said texture memory manager includes an address generator for subtracting at least one of a tile offset and an update offset.

Claim 35

The texture processor of claim 24, wherein 2×2 groups of pixels are processed as pixel quads.

Claim 36

The texture processor of claim 27, wherein said texture generator includes a quad coordinate compression block for compressing texel coordinates for each pixel quad sent to said texture memory manager, and said texture memory manager includes a quad coordinate decompression block to decompress the compressed texel coordinates for each pixel quad.