I’m working on a project using RealityKit on visionOS, and I need to implement a Vignette effect (darkening the corners of the screen) in my AR experience. Since RealityKit doesn’t seem to directly support custom shaders or post-processing effects like Vignette, I’m unsure how to proceed.

Here’s what I’ve considered so far:

1. Scene Background: Modifying the scene background, but this approach doesn’t seem to provide the flexibility I need to apply the effect across the entire view.

2. Using Metal: Integrating Metal shaders for custom rendering, though I’m not experienced with combining Metal and RealityKit.

Has anyone successfully implemented a Vignette effect or any other post-processing effect in RealityKit, specifically on visionOS? What are the best practices or possible workarounds to achieve this? Any code examples or guidance would be greatly appreciated!