Epic Games has merged a new feature into the main Unreal Engine 5 branch that can substantially improve lighting on lower-end hardware, including the Nintendo Switch 2.
As technical artist Dylan Brown explained, the new system — called Lumen Irradiance Cache — is a streamlined variant of Lumen that relies on lighting probes. It’s designed for devices that cannot handle the full Hardware Lumen pipeline.
The approach yields less detailed shadows and softer reflections, but preserves the believable lighting that defines Unreal Engine 5. Compared to having no Lumen support, this represents a significant advance for mobile platforms and underpowered consoles. Lumen Irradiance Cache speeds up lighting data collection by roughly 2.5×, translating to about a 50% boost in scene render performance.
The feature is still in early development but already shows promise. It could allow a simplified, visually pleasing version of Lumen to reach Switch 2, where developers previously avoided Lumen and Nanite because of CPU and memory constraints. Even Fortnite on Switch 2 lacks those technologies, forcing Epic to implement specialized engine optimizations.
With Lumen Irradiance Cache, that may change. If Epic continues refining the system and developers adopt it, Switch 2 titles could close the visual gap with PS5 and Xbox Series X without sacrificing performance.
The new Lumen mode provides developers with:
- enhanced lighting for scenes and interiors on low-end hardware;
- more natural light reflections;
- consistent visual presentation across UE5 platforms.
Source: iXBT.games