| Title: |
FLOATING POINT COMPUTER SYSTEM WITH FLOATING POINT MEMORY |
| Document Number: |
20120256933 |
| Publication Date: |
October 11, 2012 |
| Appl. No: |
13/494783 |
| Application Filed: |
June 12, 2012 |
| Abstract: |
A floating point rasterization and frame buffer in a computer system graphics program. The rasterization, fog, lighting, texturing, blending, and antialiasing processes operate on floating point values. In one embodiment, a 16-bit floating point format consisting of one sign bit, ten mantissa bits, and five exponent bits (s10e5), is used to optimize the range and precision afforded by the 16 available bits of information. In other embodiments, the floating point format can be defined in the manner preferred in order to achieve a desired range and precision of the data stored in the frame buffer. The final floating point values corresponding to pixel attributes are stored in a frame buffer and eventually read and drawn for display. The graphics program can operate directly on the data in the frame buffer without losing any of the desired range and precision of the data. |
| Inventors: |
Airey, John M. (Mountain View, CA, US); Peercy, Mark S. (Cupertino, CA, US); Drebin, Robert A. (Palo Alto, CA, US); Montrym, John (Los Altos Hills, CA, US); Dignam, David L. (Belmont, CA, US); Migdal, Christopher J. (Cupertino, CA, US); Loh, Danny D. (Menlo Park, CA, US) |
| Assignees: |
GRAPHICS PROPERTIES HOLDINGS, INC. (New Rochelle, NY, US) |
| Claim: |
1. A computer system having computer memory and comprising: a raster subsystem for performing a rasterization process on a primitive, the rasterization process performed in a floating point format; and a floating point memory coupled to the raster subsystem for storing a plurality of floating point color values of the primitive, the floating point color values being read out from the memory in the floating point format. |
| Claim: |
2. The computer system as defined by claim 1 further comprising: a display screen coupled to the memory for displaying an image according to the color values stored in the memory. |
| Claim: |
3. The computer system as defined by claim 1 wherein the memory comprises a frame buffer. |
| Claim: |
4. The computer system as defined by claim 1 further comprising a texture circuit coupled to the raster subsystem, the texture circuit configured to apply a texture to the primitive, the texture being specified by floating point values. |
| Claim: |
5. The computer system as defined by claim 4 further comprising a texture memory coupled to the texture circuit, the texture memory being for storing a plurality of textures in floating point values. |
| Claim: |
6. The computer system as defined by claim 5 wherein the texture memory comprises a portion of the memory. |
| Claim: |
7. The computer system as defined by claim 1 wherein the floating point format is comprised of a plurality of bits in s_e_m format, where s represents the sign, e represents the exponent, and M represents the mantissa in the formula n=M*2e. |
| Claim: |
8. The computer system as defined by claim 1 further comprising a fog circuit coupled to the raster subsystem for performing a fog function, the fog function operating on floating point color values. |
| Claim: |
9. The computer system as defined by claim 1 further comprising a blender coupled to the raster subsystem, the blender being configured to blend floating point color values. |
| Claim: |
10. The computer system as defined by claim 1 further comprising logic that performs per-fragment operations on floating point color values, the logic being coupled to the raster subsystem. |
| Claim: |
11. The computer system as defined by claim 1 wherein the raster subsystem and memory are on a single semiconductor chip. |
| Claim: |
12. The computer system as defined by claim 1 wherein the raster subsystem comprises an interconnection of electrical hardware. |
| Claim: |
13. The computer system as defined by claim 1 wherein the raster subsystem is associated with the memory in such a way that power or signal information may be transferred between the raster subsystem and the memory. |
| Claim: |
14. The computer system as defined by claim 1 wherein the raster subsystem is configured to rasterize on an entirely floating point basis. |
| Claim: |
15. The computer system as defined by claim 1 wherein at least a portion of the rasterization process is performed on a floating point basis. |
| Claim: |
16. The computer system as defined by claim 1 wherein at least a portion of the rasterization process is performed on a fixed point basis. |
| Claim: |
17. The computer system as defined by claim 1 wherein the memory is for storing floating point color values. |
| Claim: |
18. The computer system as defined by claim 1 wherein the memory is for storing at least a portion of the color values in fixed point format. |
| Claim: |
19. The computer system as defined by claim 1 wherein floating point color values are read out from the memory in the floating point format for display. |
| Claim: |
20. The computer system as defined by claim 1 wherein floating point color values are read out from the memory in the floating point format for further processing by the raster subsystem. |
| Claim: |
21. The computer system as defined by claim 1 wherein the raster subsystem performs scan conversion at least in part on a floating point basis. |
| Claim: |
22. The computer system as defined by claim 1 wherein the raster subsystem performs scan conversion entirely on a floating point basis. |
| Claim: |
23. The computer system as defined by claim 1 wherein the rasterization subsystem performs scan conversion on vertices having floating point color values. |
| Claim: |
24. The computer system as defined by claim 1 wherein the memory comprises a portion of computer memory for storing color values during or after rasterization. |
| Claim: |
25. A graphics processing method comprising: performing a rasterization process on a primitive in a floating point format; and storing a plurality of floating point color values of the primitive in floating point memory; and reading out the stored floating point color values from the memory in the floating point format. |
| Claim: |
26. The method as defined by claim 25 further comprising: displaying an image according to the color values stored in the memory. |
| Claim: |
27. The method as defined by claim 25 wherein the memory comprises a frame buffer. |
| Claim: |
28. The method as defined by claim 25 further comprising applying a texture to the primitive, the texture being specified by floating point values. |
| Claim: |
29. The method as defined by claim 28 further comprising storing a plurality of textures in floating point values in a texture memory. |
| Claim: |
30. The method as defined by claim 29 wherein the texture memory comprises a portion of the memory. |
| Claim: |
31. The method as defined by claim 25 wherein the floating point format is comprised of a plurality of bits in s_e_m format, where s represents the sign, e represents the exponent, and M represents the mantissa in the formula n=M*2e. |
| Claim: |
32. The method as defined by claim 25 further comprising performing a fog function operating on floating point color values. |
| Claim: |
33. The method as defined by claim 25 further comprising blending floating point color values. |
| Claim: |
34. The method as defined by claim 25 further comprising performing per-fragment operations on floating point color values. |
| Claim: |
35. The method as defined by claim 25 wherein a single semiconductor chip performs the rasterization process and contains the floating point memory. |
| Claim: |
36. The method as defined by claim 25 wherein the rasterization process is configured to rasterize on an entirely floating point basis. |
| Claim: |
37. The method as defined by claim 25 wherein at least a portion of the rasterization process is performed on a floating point basis. |
| Claim: |
38. The method as defined by claim 25 wherein at least a portion of the rasterization process is performed on a fixed point basis. |
| Claim: |
39. The method as defined by claim 25 wherein the memory is for storing at least a portion of the color values in fixed point format. |
| Claim: |
40. The method as defined by claim 25 wherein reading out the stored color values comprises: reading out the stored floating point color values from the memory in the floating point format; and displaying graphical data on a monitor based on the read out floating point color values. |
| Claim: |
41. The method as defined by claim 25 wherein reading out the stored color values comprises: reading out the stored floating point color values from the memory in the floating point format; and further rasterizing the read out floating point color values. |
| Claim: |
42. The method as defined by claim 25 wherein the rasterization process performs scan conversion at least in part on a floating point basis. |
| Claim: |
43. The method as defined by claim 25 wherein the rasterization process performs scan conversion entirely on a floating point basis. |
| Claim: |
44. The method as defined by claim 25 wherein the rasterization process performs scan conversion on vertices having floating point color values. |
| Claim: |
45. The method as defined by claim 25 wherein the memory comprises a portion of computer memory for storing color values during or after rasterization. |
| Current U.S. Class: |
345/531 |
| Current International Class: |
09 |
| Accession Number: |
edspap.20120256933 |
| Database: |
USPTO Patent Applications |
