Editing Global illumination (section)

==Photorealism==
[[File:Alexexterior2.jpg|thumb|left|Exterior view of an architectural model]]
[[File:Show how 3D real time ambient occlusion works 2013-11-23 10-45.jpeg|thumb|upright|Example of an ambient occlusion layer]]
Achieving accurate computation of global illumination in real-time remains difficult.<ref name="tmocg">{{cite book |title=The Magic of Computer Graphics |last=Kurachi |first=Noriko |year=2011 |publisher=CRC Press |isbn=9781439873571 |page=339 |url=https://play.google.com/store/books/details?id=YjLOBQAAQBAJ |access-date=24 September 2017}}</ref>  In real-time 3D graphics, the [[diffuse inter-reflection]] component of global illumination is sometimes approximated by an "ambient" term in the lighting equation, which is also called "ambient lighting" or "ambient color" in 3D software packages. Though this method of approximation (also known as a "cheat" because it's not really a global illumination method) is easy to perform computationally, when used alone it does not provide an adequately realistic effect. Ambient lighting is known to "flatten" shadows in 3D scenes, making the overall visual effect more bland. However, used properly, ambient lighting can be an efficient way to make up for a lack of processing power.