Sets environment properties for the entire scene
The WorldEnvironment node can be added to a scene in order to set default Environment variables for the scene. The WorldEnvironment can be overridden by an Environment node set on the current Camera. Additionally, only one WorldEnvironment may be instanced in a given scene at a time. The WorldEnvironment allows the user to specify default lighting parameters (e.g. ambient lighting), various post-processing effects (e.g. SSAO, DOF, Tonemapping), and how to draw the background (e.g. solid color, skybox).