Nanite Dreams, DOTS Nightmares: The Coding Crisis of Skylines II

Developed by Colossal Order Ltd. and published by Paradox Interactive, the management simulation game “Cities: Skylines II” made its debut for PC on October 24, 2023. Given the resounding success of its predecessor, anticipation among players was high. Upon release, the game soared to the top of Steam’s weekly sales chart and the number of concurrent players broke into the top ten.

Contrary to its sales and player count, the game’s reputation suffered, with approval ratings falling below fifty percent, a stark contrast to the previous installment’s rating of over ninety percent. The primary grievance was significant performance issues encountered in the PC version of “Cities: Skylines II.” The majority of negative reviews centered around subpar game optimization. Despite the developers’ preemptive admission of optimization issues before launch, the game’s performance fell far short of expectations, leading some to label it as one of the worst-optimized PC games of 2023, with a possibility of dropping the qualifier “one of.”

Recently, Finnish programmer Paavo Huhtala scrutinized the code of the “Cities: Skylines II” PC version and identified that a major cause of performance issues was the non-utilization of Unity Engine’s DOTS feature. This function, similar to Unreal Engine 5’s Nanite technology, automatically adjusts detail levels based on object distance to enhance performance. Furthermore, the game developers had limited other optimization strategies, which could be described as rudimentary at best, such as a lack of appropriate rendering culling mechanisms, all of which culminated in a dismal performance during gameplay.

The developers have announced that no paid DLC for “Cities: Skylines II” will be released until the game achieves “standard performance.” In addition to ongoing performance enhancements, forthcoming updates will aim to incrementally address various issues within the game. There were plans to launch “Cities: Skylines II” on PlayStation 5 and Xbox Series X|S platforms next year; however, the plethora of issues with the PC version may potentially postpone the console release.