Multi-processor graphics accelerator

• US 6,476,816 B1
• Filed: 07/15/1999
• Issued: 11/05/2002
• Est. Priority Date: 07/17/1998
• Status: Expired due to Term

• Current Assignee: RPX Corporation
• Original Assignee: 3DLabs Incorporated Limited (Creative Technology Ltd.)
• Inventors: Johnson, Timothy S., Kirkland, Dale L., Heinrich, Steven J., Whitmore, Clifford A., Buckelew, Matt E., Deming, James L.
• Primary Examiner(s): Tung, Kee M.
• Application Number:
  US09/353,495
• Time in Patent Office: 1,209 Days
• Field of Search: 345/502, 345/503, 345/505, 345/506, 345/536, 345/519, 345/422, 345/589, 345/592, 345/545
• US Class Current: 345/502
• CPC Class Codes: G06T 1/20 Processor architectures; Processor configuration, e.g. pipelining
• CPC Class Codes: G06T 15/005 General purpose rendering architectures
• CPC Class Codes: G09G 5/393 Arrangements for updating the contents of the bit-mapped memory
• CPC Class Codes: G09G 5/395 Arrangements specially adapted for transferring the contents of the bit-mapped memory to the screen G09G5/399 takes precedence

Abstract

An apparatus for displaying a polygon on a horizontal scan display device having a plurality of pixels includes first and second rasterizers that each process respective first and second sets of pixels. Each set of pixels includes vertical stripes that are transverse to the horizontal scan of the display. To that end, the first rasterizer has an input for receiving polygon data relating to the polygon. The first rasterizer determines a first set of pixels that are to be lit for display of the polygon, and also determines display characteristics of the first set of pixels. In a similar manner, the second rasterizer also includes an input for receiving polygon data relating to the polygon. The second rasterizer similarly determines a second set of pixels that are to be lit for display of the polygon, and also determines display characteristics of the second set of pixels. The first and second sets of pixels have no common pixels and are vertical stripes of pixels on the display device that are transverse to the direction of the horizontal scan.

Claims

1. An apparatus for displaying a polygon on a horizontal scan display device, the display device having a plurality of pixels that are selectively lit for displaying the polygon, the apparatus comprising:

a first rasterizer having an input for receiving polygon data relating to the polygon, the first rasterizer determining a first set of pixels that are to be lit for display of the polygon, the first rasterizer further determining display characteristics of the first set of pixels;

a second rasterizer having an input for receiving polygon data relating to the polygon, the second rasterizer determining a second set of pixels that are to be lit for display of the polygon, the second rasterizer further determining display characteristics for the second set of pixels;

the first set of pixels and second set of pixels having no common pixels,

the first set of pixels and second set of pixels each being vertical stripes of pixels on the display device, the vertical stripes being transverse to the direction of the horizontal scan.

2. The apparatus as defined by claim 1 further comprising:

a first frame buffer;

a first resolver for transferring the display characteristics for the first set of pixels into the first frame buffer;

a second frame buffer; and

a second resolver for transferring the display characteristics of the second set of pixels into the first frame buffer.

3. The apparatus as defined by claim 2 wherein the first frame buffer and second frame buffer are formed on a single integrated circuit.

4. The apparatus as defined by claim 2 wherein the first frame buffer and second frame buffer are formed on different integrated circuits.

5. The apparatus as defined by claim 2 wherein at least one of the first and second resolvers includes a plurality of resolvers.

6. The apparatus as defined by claim 2 wherein the first resolver includes a first number of subresolvers, the first frame buffer being divided into a second number of frame buffer segments, each subresolver being assigned one of the frame buffer segments for exclusive use.

7. The apparatus as defined by claim 6 where each subresolver writes to its assigned frame buffer segment only.

8. The apparatus as defined by claim 2 wherein the first resolver includes first and second subresolvers, the first subresolver transferring display characteristics of a first sub-set of pixels to the first frame buffer, the second subresolver transferring display characteristics of a second sub-set of pixels to the first frame buffer, the pixels in the first and second sub-sets of pixels being members of the first set of pixels, the first sub-set and second sub-set having pixels in the same vertical stripe.

9. The apparatus as defined by claim 1 wherein each vertical stripe includes a plurality of contiguous pixels.

10. The apparatus as defined by claim 9 wherein the first set of pixels includes a plurality of non-contiguous vertical stripes.

11. The apparatus as defined by claim 10 wherein the second set of pixels includes a plurality of non-contiguous vertical stripes.

12. The apparatus as defined by claim 1 wherein each vertical stripe has a width of one pixel.

13. The apparatus as defined by claim 1 wherein the display characteristics include intensity information.

14. The apparatus as defined by claim 1 wherein the display characteristics include color data.

15. The apparatus as defined by claim 1 wherein the display characteristics include depth and transparency data.

16. The apparatus as defined by claim 1 wherein the apparatus is a graphics accelerator.

17. The apparatus as defined by claim 1 wherein the polygon has a top edge and a bottom edge, the polygon including a plurality of vertical stripes when displayed by the display device, each vertical stripe extending the top edge to the bottom edge of the polygon.

18. A method of displaying a polygon on a display device, the display device having a plurality of pixels that are selectively lit for displaying the polygon, the polygon having associated polygon data, the method comprising:

providing a first rasterizer and a second rasterizer, a first set of pixels being assigned to the first rasterizer, a second set of pixels being assigned to the second rasterizer, the first and second sets of pixels having no common pixels, the first set of pixels being vertical stripes of pixels that are lit for displaying the polygon, the second set of pixels being vertical stripes of pixels that are lit for displaying the polygon;

broadcasting the polygon data to the first rasterizer and the second rasterizer;

controlling the first rasterizer to process polygon data relating to the first set of pixels; and

controlling the second rasterizer to process polygon data relating to the second set of pixels.

19. The method as defined by claim 18 wherein the polygon data includes polygon vertex data.

20. The method as defined by claim 18 wherein each vertical stripe includes a plurality of contiguous pixels.

21. The method as defined by claim 20 wherein the first set of pixels includes a plurality of non-contiguous vertical stripes.

22. The method as defined by claim 21 wherein the second set of pixels includes a plurality of non-contiguous vertical stripes.

23. The method as defined by claim 18 wherein the polygon is a triangle.

24. An apparatus for displaying an image on a display device having a plurality of pixels, the image comprising a set of polygons, the apparatus comprising:

a first gradient producing unit having an input for receiving a first ordered set of polygons, each polygon in the first ordered set being received in a first order, the first gradient producing unit having an output that provides gradient data for the first ordered set of polygons;

a second gradient producing unit having an input for receiving a second ordered set of polygons, each polygon in the second ordered set being received in a second order, the second gradient producing unit having an output that provides gradient data for the second ordered set of polygons

each polygon in the first ordered set of polygons and the second ordered set of polygons being members of the set of polygons;

a bus coupled to the outputs of the first and second gradient producing units, the bus also being coupled to at least one rasterizer that processes the plurality of polygons for display on the display device;

the first gradient producing unit output broadcasting the gradient data for the first ordered set of polygons to the bus in the first order;

the second gradient producing unit output broadcasting the gradient data for the second ordered set of polygons to the bus in the second order, the second output broadcasting the gradient data for the second ordered set of polygons after the gradient data for each polygon in the first ordered set of polygons is broadcasted to the bus.

25. The apparatus as defined by claim 24 further comprising:

a first rasterizer having an input for receiving the first ordered set of polygons, the first rasterizer determining a first set of pixels that are to be lit for display of each polygon in the first set of ordered polygons;

a second rasterizer having an input for receiving the first ordered set of polygons, the second rasterizer determining a second set of pixels that are to be lit for display of each polygon in the first set of ordered polygons;

the first set of pixels and second set of pixels having no common pixels,

the first set of pixels and second set of pixels each being vertical stripes of pixels on the display device.

26. The apparatus as defined by claim 25 wherein each vertical stripe includes a plurality of contiguous pixels.

27. The apparatus as defined by claim 26 wherein the first set of pixels includes a plurality of non-contiguous vertical stripes.

28. The apparatus as defined by claim 27 wherein the second set of pixels includes a plurality of non-contiguous vertical stripes.

29. The apparatus as defined by claim 24 wherein the first gradient producing unit produces gradient values for each polygon in the first ordered set of polygons.

30. The apparatus as defined by claim 24 wherein the polygons in the set of polygons are triangles having vertices and data relating to the vertices.

31. The apparatus as defined by claim 24 wherein the apparatus is a graphics accelerator.

32. The apparatus as defined by claim 24 wherein the image is displayed in 3D by the display device.