Ray-Traced Ambient Occlusion: Where objects or surfaces meet, light is occluded, creating subtle shadows. In games, this Ambient Occlusion (AO) is key to grounding objects and the smallest details. With ray tracing, we can make AO shadowing far more accurate, further improving Fortnite’s fidelity.
Ray-Traced Global Illumination: Fortnite’s maps and worlds are composed of dynamically built and destroyed objects, preventing pre-baked light interaction. Due to this, sky lights provide the only real-time environmental lighting. Ray-traced global illumination adds additional bounced light that is otherwise impossible to simulate in Fortnite.
There is one caveat, though. NVIDIA recommends to only enable ray-traced reflections while playing the competitive Battle Royale mode, while the other ray-traced effects can be safely turned on in the Creative Mode. In fact, NVIDIA is preparing an RTX showcase map called 'Treasure Run' which will be available through the Creative Mode. There's no word on Fortnite's PvE 'Save the World' mode, though we'll find out ourselves soon enough how RTX performs there.
DLSS gets a brief mention too, with the broad statement that it'll accelerate performance by 'up to three times'. Lastly, Reflex will enable lower latency in Fortnite. NVIDIA's slide shows 35 ms of system latency with Reflex enabled in Fortnite, whereas the control panel's Ultra Low Latency mode only shelves three frames off the default's 53 ms.
Unlike RTX and DLSS, Reflex will be available even on GeForce GTX 900 series graphics cards.