Cities: Skylines 2 like its predecessor is made in Unity, which means the game can be decompiled and inspected quite easily using any .NET decompiler. I used JetBrains dotPeek which has a decent Visual Studio -like UI with a large variety of search and analysis options. However static analysis doesn’t really tell us anything concrete about the rendering performance of the game. To analyze what’s going with rendering I used Renderdoc, an open source graphics debugger which has saved my bacon with some of my previous GPU-y personal projects.
An incredibly detailed look at just what’s going on under the hood to make the new Cities: Skylines 2 behave so poorly.
Wow, impressive how much in depth reporting went into this. TLDR: nothing in the scene is optimized. Details that have no impact on the scene including teeth are rendered even when zoomed out to the city level. 121 million – 1 billion vertices are processed every frame. Of course that shouldn’t matter, any responsible software engineer trained in modern software development practices will be in agreement that premature optimization is always bad. The real culprit for this kind of slowness is CPUs and GPU hardware that just can’t keep up with demanding titles like this that are ahead of their time.
/sarcasm
I have an Nvidia 3080 and I tried the game the other day and it scared me how the board fan sped up… no other game has made that board work so much. Besides, it was still slow and looked ugly.