Qualcomm Patent | Dithered Variable Rate Shading

Patent: Dithered Variable Rate Shading

Publication Number: 20190035049

Publication Date: 2019-01-31

Applicants: Qualcomm

Abstract

Aspects of this disclosure relate to a device for generating image content that includes a memory and processing circuitry coupled to the memory. The processing circuitry is configured to determine a dithered fractional VRS value for a core block based on a dithering factor for the core block and a fractional VRS value for the core block and determine a dithered fractional shading rate based on the dithered fractional VRS value. The processing circuitry is further configured to render the image based on the dithered fractional shading rate.

Background

Computing devices often utilize a graphics processing unit (GPU) to accelerate the rendering of graphics data for display. Such computing devices may include, e.g., computer workstations, mobile phones such as so-called smartphones, embedded systems, personal computers, tablet computers, and video game consoles. GPUs typically execute a graphics processing pipeline that includes a plurality of processing stages which operate together to execute graphics processing commands. A host central processing unit (CPU) may control the operation of the GPU by issuing one or more graphics processing commands to the GPU. Modern day CPUs are typically capable of concurrently executing multiple applications, each of which may utilize the GPU during execution.

Summary

This disclosure is directed to applying variable rate shading (VRS) applied by a GPU during rendering. The amount of VRS that a GPU applies, has an effect on the amount of power the GPU consumes. In some examples, the GPU generates and applies a dithering factor to a fractional amount of VRS to generate a dithered VRS value. This disclosure describes using a dithering factor to adjust VRS values that are applied such that transitions between blocks (e.g., core blocks) that are rendered (e.g., shaded) at a different variable rate are less perceivable to a user.

In an example, a method for processing data includes determining, by one or more processors implemented in circuitry, a dithered fractional VRS value for a core block based on a dithering factor for the core block and a fractional VRS value for the core block, determining, by the one or more processors, a dithered fractional shading rate based on the dithered fractional VRS value, and rendering, by the one or more processors, the image based on the dithered fractional shading rate.

In some examples, a device for generating video content includes a memory and processing circuitry coupled to the memory. The processing circuitry is configured to determine a dithered fractional VRS value for a core block based on a dithering factor for the core block and a fractional VRS value for the core block, determine a dithered fractional shading rate based on the dithered fractional VRS value, and render the image based on the dithered fractional shading rate.

In some examples, a device for graphics processing includes means for determining a dithered fractional VRS value for a core block based on a dithering factor for the core block and a fractional VRS value for the core block, means for determining a dithered fractional shading rate based on the dithered fractional VRS value, and means for rendering the image based on the dithered fractional shading rate.

In some examples, this disclosure describes a non-transitory computer-readable storage medium storing instructions that, when executed, causes a processor to determine a dithered fractional VRS value for a core block based on a dithering factor for the core block and a fractional VRS value for the core block, determine a dithered fractional shading rate based on the dithered fractional VRS value, and render the image based on the dithered fractional shading rate.

The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.