Unreal Engine 5.5’s MegaLights is essentially an experimental lighting feature that enables creators to use more lights in their 3D environments without significantly impacting performance.
Technically speaking, artists can now use thousands of movable, dynamic, and realistic area lights in a scene, complete with soft shadows as well as the ability to light volumetric fog. MegaLights uses ray tracing to create realistic soft shadows, and should have a similar impact to Nanite as well as Lumen, both of which fundamentally changed how scenes are rendered.
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As this feature heavily utilizes Ray Tracing, Hardware Lumen and Virtual Shadow Maps are required for MegaLights. The performance difference depends on how many shadow casting lights are in the scene. The more shadow casting lights are visible, the bigger performance improvement will be with MegaLights enabled,” said MxBenchmarkPC.
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