So Unity have implemented Path Tracing few months ago, it seems to be not a real-time thing, it takes dozens of seconds to compute and it does not support vegetation and Unity’s own HDRP clouds:
Path Tracing OFF:
I noticed that with Unity 6 Path Tracing is no longer marked as “Preview” despite it looking clearly underbaked and so far from the real-time solution we are seeing in games like Cyberpunk 2077 and Black Myth Wukong and Starwars Outlaws.
If Unity is serious about Path Tracing I suggest you look at the way Nvidia did (RTX Direct Illumination), it is much more performant than Unity’s solution and looks better and is real-time: developer.nvidia.com/rtx/ray-tracing/rtxdi
Yeah atm it seems to be a feature for renders and previewing ground truth lighting much like RE engine was shown to have.
But path tracing is becoming more common, even Unreal recent shadow demo is basically just path traced shadows (or maybe just more unified raytracing but regardless).
Yeah UE5’s MegaLights is basically Epic’s owns Path Traced renderer, they said it supports thousands of lights meanwhile Nvidia’s RTXDI supports millions, basically unlimited lights each contribute to GI, Shadows, Reflections etc… In Unity it is neither that nor something made for a static shot since it does not support clouds, water, vegetation…
As sacb0y said, the HDRP path tracer was designed for interactively previewing ground truth lighting. It has limitations regarding the geometry that is included in the ray-tracing acceleration structure and the number of features being supported, therefore it is not meant to be used in games.
There are indeed many advancements in this space, we are evaluating internally several approaches for path tracing, light sampling and dynamic GI, but we are not ready to announce anything publicly yet.
