[Rendering] Ground Truth Ambient Occlusion

[tebjan]

PR Details

Adds GTAO, a high-quality ambient occlusion technique.

Description

Adds a second ambient occlusion technique. It is more expensive than the existing one but has higher quality.
To not break existing projects, this effect is separate, also because it is valid to combine the two techniques.

The original work and the porting of the shaders to SDSL were done by @torinos-yt in the VL.Fuse repository:
TheFuseLab/VL.Fuse@develop...feature/GTAO

The original implementation and shaders are ported from this repo:
https://github.com/GameTechDev/XeGTAO

Motivation and Context

High-quality ambient occlusion.

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My change requires a change to the documentation.
• I have added tests to cover my changes.
• All new and existing tests passed.