Unreal Engine 5 is a combination of a few technologies: * Virtualised geometry (Nanite) allowing very detailed models * Very high quality models and textures

Unreal Engine 5 is a combination of a few technologies: * Virtualised geometry (Nanite) allowing very detailed models * Very high quality models and textures from photogrammetry (Megascans) * Real-time global illumination (Lumen) Combining these is what allows the very high fidelity demos, as they’re each step changes from the previous techniques in Unreal. Megascans (and the Quixel library) are a big part of the “photorealness” of these demos, because they’re basically literally photos.