Epic Games has added a new feature to the main branch of Unreal Engine 5 development that can significantly improve lighting even on low-performance devices, including Switch 2.
As noted by technical artist Dylan Brown, the new system called Lumen Irradiance Cache is a simplified version of Lumen technology based on working with lighting probes. It is designed for equipment that cannot handle the full version of Hardware Lumen.
The solution creates less detailed shadows and weaker reflections, but retains a realistic lighting effect — one of the key features of Unreal Engine 5. Compared to the absence of Lumen, this is a big step forward for mobile platforms and consoles with limited power. Lumen Irradiance Cache accelerates the collection of lighting data by approximately 2.5 times, which gives about 50% increase in scene rendering speed.
The feature is in the early stages of development, but already shows potential. Thanks to it, Lumen, previously available only on powerful PCs and next-generation consoles, may appear on Switch 2 in a simplified but effective version. Games like Cronos: The New Dawn, which use Unreal Engine 5, have so far done without Lumen and Nanite due to processor and memory limitations. Even Fortnite on Switch 2 does not support these technologies, so Epic had to create special engine optimizations.
Now, with the advent of Lumen Irradiance Cache, the situation may change. If Epic refines the system and developers start implementing it, the graphics of games on Switch 2 will be able to approach PS5 and Xbox Series X without losing performance.
The new Lumen mode gives developers:
- improved lighting of scenes and interiors on weak equipment;
- more natural light reflections;
- visual uniformity of projects on different UE5 platforms.
