Unreal Engine 6 features new LumenRef lighting mode

A new experimental lighting mode called ‘LumenRef’ has been discovered within the development branches of Unreal Engine 6. Visual effects artist Dylan Browne identified the feature, which serves as a new reference model for the Lumen global illumination system.

Unlike previous iterations, LumenRef utilizes a per-pixel approach that brings real-time graphics significantly closer to the quality of path tracing. In demonstrations, the system achieved high-fidelity lighting in a cyberpunk-style environment using only emissive surfaces, such as neon signs and displays, rather than traditional artificial light objects. This allows for physically accurate light distribution without the need for manual placement of hidden lights.

While the technology offers a massive reduction in computation time compared to traditional path tracers, it remains hardware-intensive. In tests involving 8K resolution, a system equipped with Nvidia hardware required approximately 30 seconds to render a single frame.