Published Paper Details:

The ongoing evolution of real-time rendering solutions has raised the bar on realism, interactivity, and scalability in modern digital applications such as gaming, architectural rendering, and virtual production. Classic rendering solutions are very reliant on hand-authored levels-of-detail and lightmaps, requiring a considerable amount of time and making real-time adaptation and changes unfeasible. Unreal Engine 5 (UE5) in April 5 2022 released two new technologies - Nanite virtualized geometry and Lumen global illumination, that target the above challenges with fully automated and GPU-enabled solutions and real-time calculation. In this work, a technical exploration of the two solutions is presented, examining their architecture, mechanics, and integration into modern rendering solutions. Nanite dynamically manages geometric detail by means of hierarchical clustering, culling on the GPU, and surface caching, eliminating the authoring needs of traditional levels-of-detail processes. Lumen enables real-time global illumination by a hybrid tracing method including screen-space approaches, distance-field propagation, and surface caching either with hardware or much cheaper solution, software ray tracing support. A comparison with more traditional solutions reveals improvements regarding production efficiency, iteration time, and image quality, besides dependencies on hardware and workflow limitations.