The author of the YouTube channel Threat Interactive continues to explore Unreal Engine. In a recent video, he decided to talk about the use of not the most advanced solutions in it.
He noted that UE developers use the outdated Lambert diffuse model — it was described back in 1760 (i.e., it is almost 265 years old at the moment).
This model cannot accurately simulate the behavior of light. At the same time, the shortcomings of this solution have long been known:
«In 1994, the inaccuracies [in the model] of Lambert became obvious when compared with a photographic sample designed to demonstrate the improvements of a new scattered light model called Oren-Nayar».
As an alternative, the Burley (2012) BRDF solution could be used, players had the opportunity to see it in action in games such as Need for Speed 2015 or Star Wars Battlefront. The projects looked realistic at the time of release and still look good today.
Some may remember the game The Callisto Protocol, which was created on Unreal Engine, in which the heroes are not «plastic». The blogger presented a diagram and explained that the developers used «Kalisto BRDF» — they took the Lambert model as a basis and improved it.
Comparison of the Lambert model with other solutions