Practical physically-based shading in film and game production

Physically based shading is increasingly important in both film and game production. By adhering to physically based, energy-conserving shading models, one can easily create high-quality, realistic materials that maintain that quality under a variety of lighting environments. Traditional "ad-hoc" models require extensive tweaking to achieve the same result, so it is no surprise that physically based models have increased in popularity in film and game production, particularly because they are often no more difficult to implement or evaluate.