Aggregate G-Buffer Anti-Aliasing for Deferred Shading

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional deferred shading techniques face challenges in processing high sampling rates due to high processing costs and storage requirements, particularly in real-time applications, leading to sub-optimal anti-aliasing and loss of sub-pixel details.

Innovation Solution

The system employs aggregate G-buffer anti-aliasing by assigning samples to clusters, combining material parameters for each cluster, and storing them in an aggregate geometry buffer, allowing for reduced storage and processing demands while maintaining high-quality anti-aliasing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If high sampling rates are used to capture sub-pixel detail, then anti-aliasing quality is improved, but processing cost and storage requirements become prohibitive

Engineering Contradiction:
Improveanti-aliasing qualityVSAvoidstorage requirements
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent segments the high-rate sample data into multiple lower-rate data streams by assigning different samples to different render targets. Instead of storing all samples for all pixels in a single large buffer, the system divides the sampling workload across multiple G-buffers, each handling a subset of samples. This segmentation reduces the memory bandwidth and storage requirements for any single buffer while maintaining the overall high sampling rate for anti-aliasing quality.

Inventive Principle:
Principle #1Segmentation

2Measurement precision

If high sampling rates are used to capture sub-pixel detail, then anti-aliasing quality is improved, but processing cost becomes prohibitive

Engineering Contradiction:
Improveanti-aliasing qualityVSAvoidprocessing cost
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The rendering process is segmented into multiple passes, with each pass processing a subset of samples to a separate render target. This allows the GPU to process samples in manageable chunks rather than attempting to process all high-rate samples simultaneously, reducing the per-pass processing cost while maintaining overall high anti-aliasing quality through the combination of multiple lower-rate renders.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system uses multiple render targets to process samples partially across different passes rather than requiring all samples to be processed in a single pass. By distributing the processing workload across multiple targeted renders, the system achieves effective high-rate anti-aliasing without the prohibitive cost of processing all samples at full rate in one operation.

Inventive Principle:
Principle #16Partial or excessive action

3Productivity

If deferred shading is used to delay shading computations, then rendering efficiency is improved, but storage and memory bandwidth costs increase at high sampling rates

Engineering Contradiction:
Improverendering efficiencyVSAvoidmemory bandwidth costs
Core Design Contradiction:
ProductivityVSQuantity of substance

Solution Approach 1:

The deferred shading system segments the G-buffer storage requirements by creating multiple render targets, each handling a subset of samples. This segmentation reduces the memory bandwidth required to read and write the geometry buffer at any given time, as each pass only needs to access a portion of the total sample data rather than the entire high-rate sample set simultaneously.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system processes samples partially across multiple deferred shading passes rather than requiring all samples to be stored and processed in a single pass. By using multiple render targets to accumulate shaded results incrementally, the system maintains rendering efficiency while reducing peak memory bandwidth costs associated with storing all high-rate samples in a single large G-buffer.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentUS9547931B2System, method, and computer program product for pre-filtered anti-aliasing with deferred shading
Publication Date: 2017.01.17 NVIDIA CORP
  • US9547931B2 patent drawing
  • US9547931B2 patent drawing
  • US9547931B2 patent drawing

AI summary

A system, method, and computer program product are provided for generating anti-aliased images. The method includes the steps of assigning one or more samples to a plurality of clusters, each cluster in the plurality of clusters corresponding to an aggregate stored in an aggregate geometry buffer, where each of the one or more samples is covered by a visible fragment and rasterizing three-dimensional geometry to generate material parameters for each sample of the one or more samples. For each cluster in the plurality of clusters, the material parameters for each sample assigned to the cluster are combined to produce the aggregate. The combined material parameters for each cluster are stored in an aggregate geometry buffer. An anti-aliased image may then be generated by shading the combined material parameters.