System and method for fast gradient pixel clears in graphics rendering

• US 7,466,319 B1
• Filed: 06/06/2002
• Issued: 12/16/2008
• Est. Priority Date: 01/08/2002
• Status: Active Grant

• Current Assignee: Xueshan Technologies Inc. (Wi-LAN Inc.)
• Original Assignee: 3Dlabs
• Inventors: Kirkland, Dale L., McKnight, William C., Deming, James L.
• Primary Examiner(s): Sajous, Wesner
• Application Number:
  US10/163,793
• Time in Patent Office: 2,385 Days
• Field of Search: 345/418, 345/421, 345/426, 345/428, 345/581, 345617-618, 345/501, 345/522, 345/690, 345/589, 345/204, 345/694, 345/556, 345/57, 382162-167, 382/254, 382/274, 358/521
• US Class Current: 345/589
• CPC Class Codes: G09G 2310/04 Partial updating of the display screen
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 5/04 using circuits for interfacing with colour displays
• 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

A system and method of maintaining a gradient in a plurality of pixels of a graphics display, such as a color or intensity gradient, where each pixel has an X coordinate, Y coordinate, and other pixel data that includes a fast-clear bit The pixels are filled on the display to create a gradient based upon the X or Y coordinates of the pixels, or a combination thereof, and when performing a pixel data operation, such as a read operation, the pixel data for a pixel with an activated fast-clear bit is ignored.

Claims

1. A graphics display system comprising a display including a plurality of pixels, each pixel having a X coordinate and a Y coordinate and data therefore wherein the plurality of pixels generate a gradient on the display, and the data for each pixel including a fast-clear bit that indicates if the data of that pixel is ignored in a pixel data operation on the system,

wherein if the pixel data is ignored, a clear value of the pixel is used to maintain the gradient on the display without a constant refresh of the pixel data, wherein the clear value is dependent on at least one coordinate of the pixel.

2. The system of claim 1, wherein the gradient is maintained by the Y coordinate data for each pixel.

3. The system of claim 1, wherein the gradient is maintained by the X coordinate data for each pixel.

4. The system of claim 1, wherein the gradient is maintained by a combination of X coordinate data and Y coordinate data for each pixel.

9. The system of claim 1, wherein the plurality of pixels maintains a color gradient on the display.

10. The system of claim 1, wherein the plurality of pixels maintains an intensity gradient on the display.

5. A graphics display system comprising a display including a plurality of pixels, each pixel having a X coordinate and a Y coordinate and data therefore wherein the plurality of pixels generate a gradient on the display, and the data for each pixel including a fast-clear bit that indicates if the data of that pixel is ignored in a pixel data operation on the system, and if the data for a pixel is ignored in a pixel data operation, that pixel retaining pixel data such that the gradient is maintained on the display;

wherein the pixel data operation is a write operation, and upon a write operation of data to a pixel, the fast-clear bit of that pixel is reset such that a subsequent pixel data operation will not ignore the data of that pixel.

6. A graphics display system comprising a display including a plurality of pixels, each pixel having a X coordinate and a Y coordinate and data therefore wherein the plurality of pixels generate a gradient on the display, and the data for each pixel including a fast-clear bit that indicates if the data of that pixel is ignored in a pixel data operation on the system, and if the data for a pixel is ignored in a pixel data operation, that pixel retaining pixel data such that the gradient is maintained on the display;

wherein the pixel data operation is a read operation, and upon a read operation of data to a pixel, if the fast-clear bit of that pixel indicates that the pixel data is to be ignored, the pixel data is ignored in response to the read operation.

7. A graphics display system comprising a display including a plurality of pixels, each pixel having a X coordinate and a Y coordinate and data therefore wherein the plurality of pixels generate a gradient on the display, and the data for each pixel including a fast-clear bit that indicates if the data of that pixel is ignored in a pixel data operation on the system, and if the data for a pixel is ignored in a pixel data operation, that pixel retaining pixel data such that the gradient is maintained on the display;

wherein the pixel data operation is a read-modify-write operation, upon the read portion of the pixel data operation to a pixel, if the fast-clear bit of that pixel indicates that the pixel data is to be ignored, the pixel data is ignored in response to the read portion and then the fast-clear bit of that pixel is reset such that a subsequent pixel data operation will not ignore the data of that pixel.

8. A graphics display system comprising a display including a plurality of pixels, each pixel having a X coordinate and a Y coordinate and data therefore wherein the plurality of pixels generate a gradient on the display, and the data for each pixel including a fast-clear bit that indicates if the data of that pixel is ignored in a pixel data operation on the system, and if the data for a pixel is ignored in a pixel data operation, that pixel retaining pixel data such that the gradient is maintained on the display;

wherein the pixel data operation is a write-update operation in which some of the data of a pixel is written to, upon a write-update operation of data to a pixel, and if the update data affects the pixel data coordinate for a color gradient in the display, then the fast-clear bit of that pixel is reset such that a subsequent pixel data operation will not ignore the data of that pixel.

11. A graphics display system comprising a display including a plurality of pixels, each pixel having a means for maintaining a gradient on the display while otherwise allowing fast clears of pixel data, by using a clear value to maintain the gradient on the display without a constant refresh of the pixel data when the pixel data for a pixel is ignored.

12. A method of maintaining a gradient in a plurality of pixels of a display, each pixel having a X coordinate and a Y coordinate and data therefore, the method comprising the steps of:

filling the plurality of pixels on a display to create a gradient thereupon;

selectively activating a fast-clear bit in the data for each pixel;

selectively performing a pixel data operation on one or more of the plurality of pixels of the display; and

ignoring pixel data for a pixel with an activated fast-clear bit when performing a pixel data operation;

wherein if the pixel data is ignored, a clear value of the pixel is used to maintain the gradient on the display without a constant refresh of the pixel data, wherein the clear value is dependent on at least one coordinate of the pixel.

13. The method of claim 12, wherein the step of filing of the pixels to create a gradient on the display is creating the gradient based upon Y coordinate data for each pixel.

14. The method of claim 12, wherein the step of filing of the pixels to create a gradient on the display is creating the gradient based upon X coordinate data for each pixel.

15. The method of claim 12, wherein the step of filing of the pixels to create a gradient on the display is creating the gradient based upon a combination of X coordinate and Y coordinate data for each pixel.

20. The method of claim 12, wherein the step of filling the plurality of pixels is filling the plurality of pixels to create a color gradient on the display.

16. A method of maintaining a gradient in a plurality of pixels of a display, each pixel having a X coordinate and a Y coordinate and data therefore, the method comprising the steps of:

filling the plurality of pixels on a display to create a gradient thereupon;

selectively activating a fast-clear bit in the data for each pixel;

selectively performing a pixel data operation on one or more of the plurality of pixels of the display; and

ignoring pixel data for a pixel with an activated fast-clear bit when performing a pixel data operation;

wherein the step of selectively performing a pixel data operation is performing a write operation, and further comprising the step of, upon a write operation of data to a pixel, deactivating the fast-clear bit of that pixel such that a subsequent pixel data operation will not ignore the data of that pixel.

17. A method of maintaining a gradient in a plurality of pixels of a display, each pixel having a X coordinate and a Y coordinate and data therefore, the method comprising the steps of:

filling the plurality of pixels on a display to create a gradient thereupon;

selectively activating a fast-clear bit in the data for each pixel;

selectively performing a pixel data operation on one or more of the plurality of pixels of the display; and

ignoring pixel data for a pixel with an activated fast-clear bit when performing a pixel data operation;

wherein the step of selectively performing a pixel data operation is performing a read operation, and further comprising the step of, upon a read operation of data to a pixel, ignoring the pixel data in response to the read operation if the fast-clear bit of that pixel is activated.

18. A method of maintaining a gradient in a plurality of pixels of a display, each pixel having a X coordinate and a Y coordinate and data therefore, the method comprising the steps of:

filling the plurality of pixels on a display to create a gradient thereupon;

selectively activating a fast-clear bit in the data for each pixel;

selectively performing a pixel data operation on one or more of the plurality of pixels of the display; and

ignoring pixel data for a pixel with an activated fast-clear bit when performing a pixel data operation;

wherein the step of selectively performing a pixel data operation is performing a read-modify-write operation, and further comprising the steps of;

upon the read portion of the pixel data operation to a pixel, ignoring the pixel data in response to the read operation if the fast-clear bit of that pixel is activated; and

deactivating the fast-clear bit of that pixel such that a subsequent pixel data operation will not ignore the data of that pixel.

19. A method of maintaining a gradient in a plurality of pixels of a display, each pixel having a X coordinate and a Y coordinate and data therefore, the method comprising the steps of:

filling the plurality of pixels on a display to create a gradient thereupon;

selectively activating a fast-clear bit in the data for each pixel;

selectively performing a pixel data operation on one or more of the plurality of pixels of the display; and

ignoring pixel data for a pixel with an activated fast-clear bit when performing a pixel data operation;

wherein the step of selectively performing a pixel data operation is performing a write-update operation in which some of the data of a pixel is written to, and further comprising the step of, upon a write-update operation of data to a pixel, if the update data affects the pixel data coordinate for the gradient on the display, then deactivating the fast-clear bit of that pixel such that a subsequent pixel data operation will not ignore the data of that pixel.