VrayGuide and VrayArt’s Alexander Vasiliuk has a look at how the V-Rayay 2 Sided Material works, and suggests some uses for creating curtains in in interior render. Alexander notes that the V-Ray 2 Sided Material can actually transmit light making it a great choice for window coverings, where one side can have a texture and a diffuse value, and the other will allow light to pass through.
