Former Returnal developer Ari Arnbjörnsson is currently working alongside CD Projekt Red to eliminate stuttering issues in Unreal Engine 5.
During a recent presentation (via Reddit user sammyjo802), former Returnal lead programmer Ari Arnbjörnsson, who now works at Epic Games as a senior software engineer, has revealed new collaborative efforts with CD Projekt Red aimed at tackling one of the most persistent technical issues with Unreal Engine i.e. stutter. The discussion came during a recent presentation where Arnbjörnsson spoke with various game developers and technical leads whose sole focus is optimizing performance and eliminating stuttering in titles built using Unreal Engine 5.
Arnbjörnsson, who previously worked at Housemarque on Returnal in Unreal Engine 4, has brought his expertise to Epic’s ongoing push to improve the stability of Unreal Engine 5. Among his collaborators is CD Projekt Red, the studio behind The Witcher and Cyberpunk 2077.
One of the key tools discussed was CD Projekt Red’s Fast-Geo Streaming plug-in, a level streaming solution developed for Unreal Engine 5.6. Designed to load and unload game assets rapidly during gameplay, the plug-in helps eliminate stutter caused by asset streaming, particularly in expansive open world games. This technology was recently showcased in The Witcher 4 tech demo and is similar in purpose to CDPR’s proprietary Turbotech system.
While console games typically avoid these issues thanks to fixed hardware and pre-compiled shaders being shipped with the game, the situation is different on PC. Given the near-infinite hardware configurations in the PC space, developers are required to ensure shaders are precompiled on the user’s system, usually during the the game’s first boot, to prevent shader compilation or Pipeline State Object (PSO) stutters. The issue isn’t inherent to Unreal Engine or any one engine. Instead, it often results from developers cutting corners during quality assurance by skipping pre-compilation processes, an oversight that became prominent in the post-DirectX 11 era.
