MULTI-SAMPLE RENDERING OF 2D VECTOR IMAGES

• US 20090033671A1
• Filed: 08/02/2007
• Published: 02/05/2009
• Est. Priority Date: 08/02/2007
• Status: Abandoned Application

• Current Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Original Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Inventors: Kallio, Kiia, Tuomi, Mika, Paananen, Jarno
• Application Number:
  US11/832,773
• Publication Number:
  US 20090033671A1
• Time in Patent Office: Days
• US Class Current: 345/545
• CPC Class Codes: G06T 11/40 Filling a planar surface by adding surface attributes, e.g. colour or texture

Abstract

A method and device for enhanced rendering providing reduced memory bandwidth requirements in a graphics processor. In the rendering process, a classification buffer of limited bit length is used for classifying the pixels. Based on the classification, a decision on the pixel color may be made without accessing the multi-sample buffer for a portion of the pixels. This reduces the memory bandwidth requirements.

Claims

1. A method for rendering a vector graphics image, comprising:

resolving pixel values based upon a pixel classification and coverage value associated with each pixel; and

producing an image in a buffer using said resolved pixel values.

2. The method of claim 1, further comprising:

determining a pixel classification and coverage value for each pixel.

3. The method according to claim 2, wherein the pixel classification comprises a background class.

4. The method according to claim 3, wherein the pixel classification further comprises unexpanded, compressed and expanded classes.

5. The method according to claim 4, wherein, in the compressed class, the coverage mask of the pixel is compressed using a lossless compression method.

6. The method according to claim 3, wherein the method further comprises clearing a portion of the memory comprising the pixel classification information buffer by setting all pixels in said portion as background.

7. The method according to claim 2, wherein said vector graphics image is rendered in tiles.

8. The method according to claim 2, wherein said rendering further comprises intermediate resolving during rendering.

9. The method according to claim 2, wherein the method further comprises converting the classification.

10. A graphics device, comprising:

memory configured to store at least a classification buffer, a multi-sample buffer and a target image buffer; and

a processor, wherein

said processor is configured to produce an image in the target image buffer by using said classification buffer and said multi-sample buffer for the pixel classification, wherein said image is produced based on the coverage value and classification of each pixel.

11. The graphics device according to claim 10, wherein said processor is configured to classify pixels into classes, comprising a background class.

12. The graphics device according to claim 11, wherein said processor is further configured to classify pixels into classes comprising unexpanded, compressed and expanded classes.

13. The graphics device according to claim 12, wherein said processor is further configured to compress in said compressed class the coverage mask of the pixel using a lossless compression method.

14. The graphics device according to claim 11, wherein said processor is configured to clear said classification buffer by setting all pixels in said classification buffer as background.

15. The graphics device according to claim 10, wherein said processor is configured to resolve pixel values using said classification and multi-sample buffers.

16. The graphics device according to claim 10, wherein said processor is further configured to render a vector graphics image in tiles.

17. The graphics device according to claim 10, wherein said processor is configured to perform intermediate resolving during rendering.

18. The graphics device according to claim 10, wherein the rendering block is coupled to an additional memory.

19. A graphics processor for processing vector graphics, comprising:

a memory configured to store at least a classification buffer, a multi-sample buffer and a target image buffer; and

processing means, wherein said processing means are configured to produce an image in the target image buffer by using said classification buffer and said multi-sample buffer for the pixel classification, wherein said image is produced based on the coverage value and classification of each pixel.