Physical Sun/Sky
Adds a procedural sun and sky to the environment.
Sun Strength: Relative strength of the sun's illumination. It is recommended to use a low value (e.g. 0.1) to avoid over-exposure.
Sun Rotation: Rotation of the sun in the sky relative to the world origin where 0 degrees locates the sun at the positive Y world axis.
Sun Elevation: Elevation of the sun (in degrees) relative to the horizon.
Sun/Sky Model: Nishita (), Hosek-Wilkie (), or Hosek-Wilkie (No-Shadow). If the "no-shadow" option is selected, shadow rays from the sun lamp will be disabled.
