Solari initial GI

[JMS55]

Objective

• Add 1-bounce RT GI

Solution

• Implement a very very basic version of ReSTIR GI https://d1qx31qr3h6wln.cloudfront.net/publications/ReSTIR%20GI.pdf
• Pretty much a copy of the ReSTIR DI code, but adjusted for GI.
• Didn't implement the jacobian resampling, or add more spatial samples, or do anything needed for better quality.
• Didn't try to improve perf at all yet (it's actually faster than DI though, unfortunately 😅)
• Didn't spend any time cleaning up the shared abstractions between DI/GI

---

Showcase