Unreal Engine offers a flexible lighting toolkit built around a few core actor types. Directional Lights simulate distant sources like the sun with parallel rays and are paired with a Sky Atmosphere for outdoor illumination. Point Lights emit in all directions from a single point, and Spot Lights cast a cone with falloff. Each light has a Mobility property that determines how it interacts with baking and runtime updates. Static lights are baked into lightmaps and cannot change at runtime. Stationary lights can change color and intensity at runtime, cast baked shadows from static geometry, and only dynamic shadows from movable objects. Movable lights are fully dynamic, casting real-time shadows and movable specular highlights at the highest performance cost.
Unreal Engine 5 emphasizes Lumen, a dynamic global illumination and reflections system that updates in real time using hardware ray tracing or a software fallback. Lumen replaces traditional baked lightmaps in many workflows and is enabled through Project Settings → Rendering by setting Global Illumination Method to Lumen. It requires compatible materials, dynamic lighting, and Mesh Distance Fields. Reflection Capture actors store cubemaps of the surrounding environment so that shiny, low-roughness materials can reflect nearby geometry. Sky Lights capture and re-emit the surrounding scene as ambient lighting, essential for interiors and realistic global illumination. A Lightmass Importance Volume marks a region of the level where baked lighting should be prioritized; placing it around the playable area speeds up lightmap baking and improves quality where it matters.
Post Process Volumes apply screen-space effects such as bloom, tone mapping, ambient occlusion, color grading, vignette, and exposure. Exposure Bias in a Post Process Volume adjusts overall brightness without affecting actual lighting. Atmospheric Fog and Exponential Height Fog add distance-based fading and atmospheric scattering. Volumetric Fog produces real lighting interaction, god rays, and visible light shafts. The Sequencer editor is used to author cutscenes and animated events by keyframing cameras, actors, and properties over time. For performance diagnostics, console commands such as stat unit, stat GPU, stat FPS, and Profile GPU reveal frame time, game thread time, render thread time, and GPU pass breakdowns. Profile GPU in particular lists per-pass rendering cost and identifies overdraw or expensive shaders.