Leveraging control surface fast clears to optimize 3D operations

Patent metadata

Field	Value
Publication number	US-11763515-B2
Application number	US-202117206584-A
Country	US
Kind code	B2
Filing date	Mar 19, 2021
Priority date	Sep 28, 2017
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

One embodiment provides a graphics processor comprising a hardware graphics rendering pipeline configured to perform multisample anti-aliasing, the hardware graphics rendering pipeline including pixel processing logic to determine that each sample location of a pixel of a multisample surface is associated with a clear value and resolve a color value for the pixel to a non-multisample surface via a write of metadata to indicate that the pixel has the clear value. The resolve can be a stenciled resolve that automatically bypasses execution of a pixel shader for pixels having clear color data.

First claim

What is claimed is:

1. A graphics processor comprising:
a hardware graphics rendering pipeline configured to perform multisample anti-aliasing for a multisample surface in a memory associated with the graphics processor, the hardware graphics rendering pipeline including pixel processing circuitry to:
resolve pixel data in the multisample surface via conditional generation of color data for a non-multisample surface in the memory associated with the graphics processor, the conditional generation performed based on a source control surface for the multisample surface, wherein the conditional generation of the color data includes to:
invoke a pixel shader to resolve a first pixel of the multisample surface in response to a determination that one or more sample locations of the first pixel are associated with a non-clear color value; and
in response to a determination that each sample location of a second pixel is associated with a clear color value, bypass invocation of the pixel shader for the second pixel and set the clear color value of the non-multisample surface to the clear color value of the multisample surface.

2. The graphics processor as in claim 1 , the pixel processing circuitry including:
first circuitry to execute the pixel shader for the first pixel in response to invocation of the pixel shader for the first pixel; and
second circuitry to gate invocation of the pixel shader for the second pixel based on metadata for the second pixel stored in the source control surface.

3. The graphics processor as in claim 2 , wherein to execute the pixel shader for the first pixel includes to write a resolved color value for sample locations of the first pixel of the multisample surface to the non-multisample surface, wherein the resolved color value is an average color value of sample locations of the first pixel.

4. The graphics processor as in claim 2 , wherein to gate invocation of the pixel shader for the second pixel is to prevent divergence of a shader thread associated with the second pixel.

5. The graphics processor as in claim 4 , wherein the second circuitry is to test the metadata for the second pixel within the source control surface to determine if the metadata indicates that the second pixel is set to the clear color value.

6. The graphics processor as in claim 5 , wherein to test the metadata for the second pixel includes to test a metadata value associated with each of a plurality of sample locations of the second pixel.

7. The graphics processor as in claim 6 , the pixel processing circuitry to dispatch a stenciled multisample resolve draw to the pixel processing circuitry to conditionally generate the color data for the non-multisample surface.

8. The graphics processor as in claim 7 , wherein in response to a determination that each sample location of the second pixel is associated with a clear color value, the pixel processing circuitry is to issue a write command to write metadata for the second pixel to a destination control surface for the non-multisample surface, the metadata for the second pixel to indicate that the second pixel resolves to the clear color value.

9. The graphics processor as in claim 8 , wherein the pixel processing circuitry is to process the write command independently of the pixel shader.

10. A graphics processing system comprising:
a memory; and
a graphics processor coupled with the memory, the graphics processor including a hardware graphics rendering pipeline configured to resolve a multisample surface in memory of the graphics processor to a non-multisample surface, the hardware graphics rendering pipeline including pixel processing circuitry to:
determine that each sample location of a first pixel of a multisample surface is associated with a clear value via a read of a source control surface associated with the multisample surface, the source control surface to store metadata for the multisample surface;
resolve a color value for the first pixel to the non-multisample surface via a write of metadata to a destination control surface, the metadata to indicate that the first pixel has the clear value;
determine that multiple sample locations of a second pixel of the multisample surface contains a single non-clear value via a read of metadata for the second pixel from the source control surface;
read a clear color value associated with the multisample surface, the clear color value to indicate a color associated with the clear value; and
write a resolved color value for the second pixel of the multisample surface to the non-multisample surface, wherein the resolved color value is an average color value of sample locations of the second pixel.

11. The graphics processing system as in claim 10 , wherein the pixel processing circuitry is further to write metadata to the destination control surface to indicate that the second pixel has a non-clear value.

12. The graphics processing system as in claim 10 , wherein the write of the metadata to the destination control surface for the first pixel is associated with a fast clear performed on the non-multisample surface, the fast clear to set metadata associated with the non-multisample surface to indicate that each pixel of the non-multisample surface is set to the clear color.

13. A method comprising:
performing multisample anti-aliasing for a multisample surface in a memory associated with a graphics processor;
resolving pixel data in the multisample surface via conditional generation of color data for a non-multisample surface in the memory associated with the graphics processor, the conditional generation performed based on a source control surface for the multisample surface, wherein the conditional generation of the color data includes:
invoking a pixel shader to resolve a first pixel of the multisample surface in response to a determination that one or more sample locations of the first pixel are associated with a non-clear color value; and
in response to a determination that each sample location of a second pixel is associated with a clear color value, bypassing invocation of the pixel shader for the second pixel and setting the clear color value of the non-multisample surface to the clear color value of the multisample surface.

14. The method as in claim 13 , further comprising:
executing the pixel shader for the first pixel in response to invocation of the pixel shader for the first pixel via first circuitry of a hardware graphics rendering pipeline of the graphics processor; and
gating invocation of the pixel shader for the second pixel via second circuitry of the hardware graphics rendering pipeline based on metadata for the second pixel stored in the source control surface.

15. The method as in claim 14 , wherein executing the pixel shader for the first pixel includes writing a resolved color value for the one or more sample locations of the pixel of the multisample surface to the non-multisample surface, wherein the resolved color value is an average color value of sample locations of the first pixel.

16. The method as in claim 14 , wherein gating invocation of the pixel shader for the second pixel prevents divergence of a shader thread associated with the second pixel and the second circuitry is to test the metadata for the second pixel within the source control surface to determine if the metadata indicates that the second pixel is set to the clear color value, wherein to test the metadata for the second pixel includes to test a metadata value associated with each of a plurality of sample locations of the second pixel.

17. The method as in claim 16 , wherein i

Assignees

• Intel Corp

Inventors

• Burke Devan
• Venkatesh Abhishek
• Schluessler Travis

Classifications

• G06T15/04 Primary

  Texture mapping · CPC title

• G06T15/005

  General purpose rendering architectures · CPC title

• G06T15/80

  Shading · CPC title