This is the documentation for Enlighten.
Emissive surfaces
With Enlighten any surface that is included in the radiosity computation can become a light source. Surfaces that emit light are called emissive surfaces.
An emissive surface appears bright even when no light is falling on it. The apparent brightness of the surface in your engine may be defined by properties of its material.
It is intuitive to automatically make this type of surface into a light source that emits an amount of light that matches its apparent brightness.
To give the artist full control, we recommend to allow them to adjust the brightness of the light emitted by the surface independently from its apparent brightness.
While the game is running, the emissive colour and brightness of the surface can change, but the surface cannot be moved.