With Epic’s release of the full Unreal Engine 4 to subscribers, Lionhead stopped to answer some questions regarding the use of dynamic global illumination tech that has been recently integrated into the UE4 for Fable Legends.

According to the studio, some work has been done to optimize the engine’s cascaded shadow maps and they have developed an implementation of Cyrtek's Light Propagation Volumes that has been specifically targeted to modern GPUS like what you can find in the Xbox One.

We use compute shaders to generate a high quality voxel representation of the scene's geometry, which we use to provide secondary occlusion and multiple light bounces.

The comparison between the old and new is apparent when reviewing some of the before and after screenshots below.