SSAO is a shadow calculation method that counts the illuminance of each pixel by examining the exposure to diffuse light. It makes the game scene look more natural. While this technique has been known and available in games for a long time (first seen with Crysis in 2007), it’s new to the graphics engine of American Truck Simulator.
With SSAO enabled, building surfaces give a sense of depth and look more natural. Each break gains additional shadow and becomes more visible. Ambient lighting demands high hardware requirements. We did not notice any noticeable slowdown in our tests with the Ryzen 5 1600 and GTX 1050 Ti.
Of course, the addition of SSAO isn’t the only change the patch brings. Many locations were relocated and Las Vegas was rebuilt. These are mostly urban roads and some buildings. A similar change is also present in El Centro. Added several highways, improved pumps at gas stations, and fixed many detected bugs. Gearboxes and dead zones on trucks have been improved.
Also, the Route Advisor window and navigation instructions have been slightly modified. The FMOD sound engine has also been updated to version 2.01.01. The full list of fixes can be found on the SCS blog. Finally, you can watch the following video published by SCS presenting the changes in the 1.38 patch.