Shared access texturing of computer graphic images

• US 5,892,517 A
• Filed: 06/10/1996
• Issued: 04/06/1999
• Est. Priority Date: 01/02/1996
• Status: Expired due to Term

• Current Assignee: Rambus Inc.
• Original Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Inventors: Rich, Henry H.
• Primary Examiner(s): Jankus, Almis R.
• Application Number:
  US08/661,194
• Time in Patent Office: 1,030 Days
• Field of Search: 395/125-131, 345/425-431
• US Class Current: 345/582
• CPC Class Codes: G06T 1/60 Memory management

Abstract

Methods, apparatus and computer program products for applying texture to the surfaces of objects in graphics images utilizing texture patterns organized into blocks of texels. Each block of texels is preferably compressed using a block-oriented compression technique and then compressed further using entropy coding. Multiple processing elements rendering an image make requests for texels by address. The texel addresses are converted to block addresses, and the block addresses are consolidated and redundant requests are eliminated. The blocks are retrieved from texture pattern memory, performs entropy decoding, and transfers the data to the processor array such that the likelihood of redundant retrieval of texture data is reduced. The processing elements utilize the retrieved texture data for calculation of pixel values utilizing the texture information.

Claims

1. A system for texturing surfaces displayed as computer graphics images of modeled objects having defined surfaces on a display of pixels having pixel addresses comprising:

(a) block storage means for storing texture patterns composed of texels having texel addresses, said texture patterns being stored in blocks of texels with each block having a pre-defined block address;

(b) processor means for computing the texel addresses associated with said pixel addresses and for processing texel data into pixel data;

(c) address converter means coupled to said processor means for converting texel addresses into block addresses;

(d) sort means coupled to said address converter means for sorting block addresses received from said address converter means whereby multiple address references to the same block are consolidated to a single address referencing the block to provide consolidated block address information wherein each of the consolidated block addresses references different blocks of texels; and

(e) retrieval means coupled to said sort means and to said block storage means for retrieving texture pattern blocks based on said consolidated block address information from said block storage means and for supplying said retrieved texture pattern blocks to said processor means.

2. The system of claim 1 wherein blocks of texel data in said block storage means comprises compressed data representations of said blocks of texel data, and wherein said processor means includes means for decompressing retrieved blocks of texel data into texels.

3. The system of claim 1 wherein said processor means includes a plurality of processing elements interconnected by a predetermined logic bus.

4. The system of claim 3 wherein said sort means includes a plurality of inputs and means for performing comparisons concurrently and wherein said plurality of inputs are connected to receive data from said logic bus.

5. The system of claim 3 wherein said retrieval means includes means for broadcasting to said processing elements the block addresses of retrieved texel data, and wherein each of said plurality of processing elements stores the block addresses of texel data associated with said processing element and compares said stored block addresses to the broadcast block addresses of retrieved texel data to thereby identify predetermined texel data associated with said processing element.

6. The system of claim 5 wherein said means for broadcasting to said processing elements includes means for broadcasting a code representing the subsequent sequence in which data will be broadcast, and wherein said processing elements receive said code and selectively identify the broadcast data based on to the sequence in which the broadcast data is sent.

7. The system of claim 5 wherein blocks of texel data in said block storage means comprises compressed data representations of said blocks of texel data, and wherein said processor means includes means for decompressing retrieved blocks of texel data into texels.

8. The system of claim 7 wherein said blocks of texel data in said block storage means are compressed using entropy coding and wherein said retrieval means includes an entropy decoder connected to receive input from said block storage means and providing entropy decoded output to said processor means.

9. The system of claim 1 wherein said sort means includes a plurality of inputs for receiving block addresses from said processor means and wherein said sort means concurrently sorts information received from said plurality of inputs.

10. The system of claim 1 wherein said processing elements and said sort means are elements of a single integrated circuit.

11. A method for texturing the surfaces of modeled objects in a system for rendering computer graphics images of modeled objects having defined surfaces on a display of pixels having pixel addresses, comprising the steps of:

storing texture patterns of texels arranged in blocks with each texel having a texel address, and each block having a block address;

computing the texel addresses for each pixel of at least one object surface of said modeled objects to provide a plurality of surface texel addresses for the object surface;

determining a plurality of block addresses associated with the plurality of surface texel addresses to provide a plurality of surface block addresses corresponding to the plurality of surface texel addresses for the object surface;

comparing each of the plurality of surface block addresses to others of the plurality of surface block addresses and removing any duplicate surface block addresses to provide sorted surface block addresses wherein each of the sorted surface block addresses is associated with different blocks of stored texture pattern data;

retrieving blocks of stored texture pattern data associated with the sorted surface block addresses; and

generating the pixel texture values associated with the at least one object surface from the retrieved blocks of stored texture pattern data.

12. A method for texturing the surfaces of modeled objects according to claim 11, wherein said computing, said determining, said comparing, said retrieving and said generating steps are repeated for each object in the image.

13. A method for texturing the surfaces of modeled objects according to claim 11, wherein said storing step includes compression of the block prior to storage, and wherein said retrieving step includes decompression of the block after retrieval.

14. A method for texturing the surfaces of modeled objects according to claim 11, wherein said comparing step concurrently compares the surface block addresses.

15. An apparatus for texturing the surfaces of modeled objects in a system for rendering computer graphics images of modeled objects having defined surfaces on a display of pixels having pixel addresses, the apparatus comprising:

means for storing texture patterns of texels arranged in blocks with each texel having a texel address, and each block having a block address;

means for computing the texel addresses for each pixel of at least one object surface of said modeled objects to provide a plurality of surface texel addresses for the object surface;

means for determining a plurality of block addresses associated with the plurality of surface texel addresses to provide a plurality of surface block addresses corresponding to the plurality of surface texel addresses for the object surface;

means for comparing each of the plurality of surface block addresses to others of the plurality of surface block addresses and removing any duplicate surface block addresses to provide sorted surface block addresses wherein each of the sorted surface block addresses is associated with different blocks of stored texture pattern data;

means for retrieving blocks of stored texture pattern data associated with the sorted surface block addresses; and

means for generating the pixel texture values associated with the at least one object surface from the retrieved blocks of stored texture pattern data.

16. An apparatus for texturing the surfaces of modeled objects according to claim 15, wherein said means for computing computes the texel addresses to provide surface texel addresses for each object in the image.

17. An apparatus for texturing the surfaces of modeled objects according to claim 15, wherein said means for storing includes compression means for compressing the block prior to storage, and wherein said means for retrieving includes decompression means for decompressing the block after retrieval.

18. An apparatus for texturing the surfaces of modeled objects according to claim 15, wherein said means for comparing concurrently compares the surface block addresses.

19. A computer program product for texturing the surfaces of modeled objects in a system for rendering computer graphics images of modeled objects having defined surfaces on a display of pixels having pixel addresses, the computer program product comprising:

a computer-readable storage medium having computer-readable program code means embodied in said medium, said computer-readable program code means comprising;

computer readable program code means for storing texture patterns of texels arranged in blocks with each texel having a texel address, and each block having a block address;

computer readable program code means for computing the texel addresses for each pixel of at least one object surface of said modeled objects to provide a plurality of surface texel addresses for the object surface;

computer readable program code means for determining a plurality of block addresses associated with the plurality of surface texel addresses to provide a plurality of surface block addresses corresponding to the plurality of surface texel addresses for the object surface;

computer readable program code means for comparing each of the plurality of surface block addresses to others of the plurality of surface block addresses and removing any duplicate surface block addresses to provide sorted surface block addresses wherein each of the sorted surface block addresses is associated with different blocks of stored texture pattern data;

computer readable program code means for retrieving blocks of stored texture pattern data associated with the sorted surface block addresses; and

computer readable program code means for generating the pixel texture values associated with the at least one object surface from the retrieved blocks of stored texture pattern data.

20. An apparatus for texturing the surfaces of modeled objects according to claim 19, wherein said computer readable program code means for computing computes the texel addresses to provide surface texel addresses for each object in the image.

21. An apparatus for texturing the surfaces of modeled objects according to claim 19, wherein said computer readable program code means for storing includes computer readable program code means for compressing the block prior to storage, and wherein said computer readable program code means for retrieving includes computer readable program code means for decompressing the block after retrieval.

22. An apparatus for texturing the surfaces of modeled objects according to claim 19, wherein said computer readable program code means for comparing concurrently compares the surface block addresses.

23. A system for texturing surfaces displayed as computer graphics images of modeled objects having defined surfaces on a display of pixels having pixel addresses comprising:

(a) block storage means for storing texture patterns composed of texels having texel addresses, said texture patterns being stored in blocks of texels with each block having a pre-defined block address;

(b) processor means for computing the texel addresses associated with said pixel addresses and for processing texel data into pixel data wherein the processor means comprises a plurality of processor interconnected by a logic bus;

(c) address converter means coupled to said processor means for converting texel addresses into block addresses;

(d) sort means coupled to said address converter means for sorting block addresses received from said address converter means whereby multiple address references to the same block may be consolidated to provide consolidated block address information wherein the sort means includes a plurality of inputs and means for performing comparisons concurrently and wherein said plurality of inputs are connected to receive data from said logic bus; and

(e) retrieval means coupled to said sort means and to said block storage means for retrieving texture pattern blocks based on said consolidated block address information from said block storage means and for supplying said retrieved texture pattern blocks to said processor means.

24. The system of claim 23 wherein blocks of texel data in said block storage means comprise compressed data representations of said blocks of texel data, and wherein said processor means includes means for decompressing retrieved blocks of texel data into texels.

25. The system of claim 23 wherein said retrieval means includes means for broadcasting to said processing elements the block addresses of retrieved texel data, and wherein each of said plurality of processing elements stores the block addresses of texel data associated with said processing element and compares said stored block addresses to the broadcast block addresses of retrieved texel data to thereby identify predetermined texel data associated with said processing element.

26. The system of claim 25 wherein said means for broadcasting to said processing elements includes means for broadcasting a code representing the subsequent sequence in which data will be broadcast, and wherein said processing elements receive said code and selectively identify the broadcast data based on the sequence in which the broadcast data is sent.

27. The system of claim 25 wherein blocks of texel data in said block storage means comprises compressed data representations of said blocks of texel data, and wherein said processor means includes means for decompressing retrieved blocks of texel data into texels.

28. The system of claim 27 wherein said blocks of texel data in said block storage means are compressed using entropy coding and wherein said retrieval means includes an entropy decoder connected to receive input from said block storage means and providing entropy decoded output to said processor means.

29. A system for texturing surfaces displayed as computer graphics images of modeled objects having defined surfaces on a display of pixels having pixel addresses comprising:

(a) block storage means for storing texture patterns composed of texels having texel addresses, said texture patterns being stored in blocks of texels with each block having a pre-defined block address;

(b) processor means for computing the texel addresses associated with said pixel addresses and for processing texel data into pixel data;

(c) address converter means coupled to said processor means for converting texel addresses into block addresses;

(d) sort means coupled to said address converter means for sorting block addresses received from said address converter means whereby multiple address references to the same block may be consolidated to provide consolidated block address information wherein said sort means includes a plurality of inputs for receiving block addresses from said processor means and wherein said sort means concurrently sorts information received from said plurality of inputs; and

(e) retrieval means coupled to said sort means and to said block storage means for retrieving texture pattern blocks based on said consolidated block address information from said block storage means and for supplying said retrieved texture pattern blocks to said processor means.