VARIABLE FRAGMENT SHADING WITH SURFACE RECASTING

• US 20150022537A1
• Filed: 07/19/2013
• Published: 01/22/2015
• Est. Priority Date: 07/19/2013
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: NVIDIA Corporation
• Inventors: Lum, Eric B., Dimitrov, Rouslan L., Llamas, Ignacio, Uralsky, Yury, Meixner, Albert, Neill, Patrick James
• Granted Patent: US 9,355,483 B2
• Time in Patent Office: Days
• US Class Current: 345/522
• CPC Class Codes: G06T 11/40 Filling a planar surface by adding surface attributes, e.g. colour or texture

Abstract

A system, method, and computer program product are provided for shading primitive fragments. A target buffer may be recast when shaded samples that are covered by a primitive fragment are generated at a first shading rate using a first sampling mode, the shaded samples are stored in the target buffer that is associated with the first sampling mode and the first shading rate, a second sampling mode is determined, and the target buffer is associated with the second sampling mode. A sampling mode and/or shading rate may be changed for a primitive. A primitive fragment that is associated with a first sampling mode and a first shading rate is received and a second sampling mode is determined for the primitive fragment. Shaded samples corresponding to the primitive fragment are generated, at a second shading rate, using the second sampling mode and the shaded samples are stored in a target buffer.

Claims

1. A method, comprising:

generating shaded samples that are covered by a primitive fragment at a first shading rate using a first sampling mode;

storing the shaded samples in a target buffer that is associated with the first sampling mode and the first shading rate;

determining a second sampling mode; and

associating the target buffer with the second sampling mode.

2. The method of claim 1, further comprising accessing the target buffer according to the second sampling mode.

3. The method of claim 2, further comprising displaying the target buffer at a resolution corresponding to the second sampling mode.

4. The method of claim 1, wherein a graphics processor reinterprets pixel dimensions of the target buffer based the second sampling mode.

5. The method of claim 1, wherein the first sampling mode is a multi-sample sampling mode and the second sampling mode is a single sample per pixel.

6. The method of claim 1, wherein the first sampling mode is a single-sample per pixel and the second sampling mode is a multi-sample sampling mode that includes multiple samples per pixel.

7. The method of claim 1, further comprising generating additional shaded samples that are covered by an additional primitive fragment at a second shading rate using the second sampling mode.

8. The method of claim 7, wherein either the first shading rate or the second shading rate is more than one pixel per thread shader program execution.

9. The method of claim 7, further comprising inserting additional instructions into a shader program to offset texture coordinate derivatives computed for the additional shaded samples, wherein the texture coordinate derivatives are offset for the second sampling mode relative to the first sampling mode.

10. The method of claim 1, wherein the determining of the second sampling mode comprises estimating color variability in a group of pixels.

11. A method of shading, comprising:

receiving a primitive fragment that is associated with a first sampling mode and a first shading rate;

determining a second sampling mode for the primitive fragment;

generating, at a second shading rate, shaded samples corresponding to the primitive fragment using the second sampling mode; and

storing the shaded samples in a target buffer.

12. The method of claim 11, wherein the second shading rate is less than the first shading rate.

13. The method of claim 11, wherein the second shading rate is can be either greater or lesser than one shaded sample per pixel.

14. The method of claim 11, wherein the determining of the second sampling mode comprises estimating color variability in a group of pixels.

15. The method of claim 11, wherein the first sampling mode is a super-sample sampling mode configured to compute a shaded sample for each sample location of each pixel and the second sampling mode is a multi-sample sampling mode configured to compute a single shaded sample for each pixel.

16. The method of claim 11, further comprising inserting additional instructions into a shader program to offset texture coordinates and derivative computations when the target buffer is recast.

17. The method of claim 11, further comprising recasting the target buffer represented in a first resolution corresponding to the first sampling mode to a second resolution corresponding to the second sampling mode.

18. The method of claim 17, wherein the first resolution is higher than the second resolution.

19. The method of claim 17, wherein the second resolution is higher than the first resolution.

20. A system comprising;

a memory storing a target buffer; and

one or more processing cores coupled to the memory and configured to;

receive a primitive fragment that is associated with a first sampling mode and a first shading rate;

determine a second sampling mode for the primitive fragment;

generate, at a second shading rate, shaded samples corresponding to the primitive fragment using the second sampling mode; and

store the shaded samples in the target buffer.