Epic Games announced the completion of Unreal Engine 4.7, the firm's biggest release yet. One of the major new features involves tree foliage, Unreal Engine 4.7 has a new Foliage Shading Model that allows light to be transmitted through grass, leaves, paper and other materials to achieve higher realism. Additionally, the foliage system has been optimized to support huge, open environments. A full overview of Unreal Engine 4 can be found at the Unreal Engine boards.
REALISTIC FOLIAGE LIGHTING
The new Foliage Shading Model allows light to be transmitted through grass, leaves, paper, and other materials
Diffuse lighting on the opposite side of the surface becomes transmissive lighting on the side being shaded
Transmissive lighting is a mix of wrap-around diffuse with a view dependent lobe for backscattering
Subsurface color filters this lighting and can be used to represent varying thickness as well (e.g. leaf veins)
Note that using opacity with this shading model will only affect shadow falloff distance
FOLIAGE RENDERING FOR LARGE WORLDS
The foliage system has been optimized to to support huge, open environments!
We now use a hierarchical system for managing and culling of foliage that scales to millions of instances! Also, we now smoothly transition between mesh LODs with a temporal fade to eliminate the annoying pop when switching LODs!