Making Connections: Real-Time Path-Traced Light Transport in Game Engines

Path traced effects in games have been a dream of many since the early days of real-time rendering. The advent of hardware accelerated ray tracing and recent advances in algorithms derived from Reservoir-based Spatio-Temporal Importance Sampling (ReSTIR) have turned those dreams into reality. In this 2024 Advanced Graphics Summit talk, Evan and Adam discuss the theoretical and practical elements necessary to add real-time path-traced lighting to an advanced, modern game engine (Unreal Engine 5).
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[@mikda360]

Impressive! Would like to download the demo sequence, youtube made a number on the quality with the compression

[@snarkyboojum]

I'm a graphics noob, but I would have expected to see realtime reflections of the fireworks in the pond in the middle of the scene, and more realtime shadows being demonstrated as the camera moved around the scene. The sudden brightening of the scene on the ground before the tent at 6:41 was a bit confusing too. Where is the light source that created that sudden change in illumination? I mean, I'm looking at a pretty blurry 1080p video anyway, and the scene is very beautiful, but the lack of dynamism in the shadow rendering on display here was a bit surprising to me.

[@Sweenus987]

Edit: At 29:14 they talk about the artifact in question.
For the lighting, my best guess is that the side of the building on the right of the path to the tent wasn't contributing to bounce lighting and as the camera turned enough, it started to and initially bounced way too much until it normalised. You can see how bright the building is as the camera gets closer to the tent

[@jaspersgames4094]

amazing work!