Environment lighting (aka ambient) is a key component of any renderer.
It's implemented like the Environment lighting of BI render for Approximate Gather mode. It support "Sky Color" and "White" Environment lighting modes.
It would be great if the user could see actual lighting conditions right in the Blender viewport instead of waiting for the renderer to complete the final image, exporting for external renderer or for a game engine.
Original author: valentin_b4w
Alexander (Blend4Web Team)