This is the documentation for Enlighten.
To reduce the latency of lighting updates in a large world, Enlighten can automatically reduce the lighting resolution when the viewer is far away. When lighting LOD is enabled, distant areas use a lower lighting resolution.
To reduce the latency of lighting updates in nearby areas, Enlighten normally updates distant areas at a reduced rate. When lighting LOD is enabled, distant areas can instead be updated at the full rate.
This option is experimental and has some limitations.
For meshes with the the Contribute Lightmap lighting mode, you can use lightmap LOD. When enabled, Enlighten generates multiple LODs within the lightmap, each with progressively fewer lightmap pixels. As the camera moves further from the mesh, Enlighten switches to a lightmap LOD with fewer pixels.
To enable lightmap LOD for all static meshes in the world:
2 or higher.To set the distance from the camera at which Enlighten switches to a lightmap LOD with fewer pixels, use the Lightmap LOD Distance property. When the distance is 0, Enlighten never switches to a reduced lightmap LOD.
After Enlighten switches to a lightmap LOD with fewer pixels, the mesh is drawn with the lowest detail mesh LOD.
The transition between Enlighten lightmap LOD levels currently isn't smoothly blended, and can result in a visible pop.
To set the distance from the camera at which Enlighten switches to a reduced resolution of probes, use the Probe LOD Distance property. When the distance is 0, Enlighten uses the highest resolution probes for all meshes.
This property has no effect when automatic probe placement is disabled.
To enable lighting LOD for a landscape actor:
By default, Enlighten automatically chooses the number of detail levels. You can also specify a minimum number of detail levels: in World Settings, under Enlighten, set the Minimum Landscape LOD Count before running the precompute.
To set the distance from the camera at which Enlighten switches to a reduced resolution for the landscape lightmap, use the Landscape LOD Distance property. When the distance is 0, Enlighten uses the full lighting resolution for all parts of the Landscape.