The transition to a newer version of the Unreal Engine became a separate test for GSC Game World during the work on the 2.0 update for S.T.A.L.K.E.R. 2. The developers abandoned Unreal Engine 5.1 in favor of version 5.5.4. The changes in the engine turned out to be so large-scale that the transfer process itself turned out to be far from simple.
This is reported by dev.ua.
The problem was that during the development of S.T.A.L.K.E.R. 2, the Unreal Engine 5.1 engine underwent significant changes and significantly differed from the initial version. During the development, the GSC team seriously reworked it, adding a lot of its own developments and code. Therefore, a regular update of the engine actually turned into a complex technical work of adapting the engine that had already been modified for the game.
The scale of the difficulties was succinctly conveyed by the COO and head of creative direction of GSC Maria Grygorovych. When asked about the transition, she replied:
“Can I cry?”
What were the difficulties
Maria Grygorovych explained that the main problem was the deep adaptation of Unreal Engine 5.1 to the needs of S.T.A.L.K.E.R. 2. The team added a large amount of its own code to the engine, which made its update much more time-consuming. According to her, it is much easier for projects with a minimally modified, “vanilla” version of the engine to switch to the newer Unreal Engine.
Yevhen Grygorovych called the transition process “crazy.” The game was initially developed on Unreal Engine 4, and later the studio switched to an early version of Unreal Engine 5. At that time, the engine did not yet have all the necessary tools for working with a large-scale open world, so GSC had to independently refine it and create its own systems.
Later, Epic Games added solutions with similar functions to new versions of Unreal Engine. However, to switch to them, GSC had to actually redo a significant part of the work already done. Because of this update, S.T.A.L.K.E.R. 2 required much more time and effort from the team than a similar process in other projects.
Despite the complexity of the work, GSC believes that switching to a newer version of the engine was the right decision. According to studio executives, after the update, S.T.A.L.K.E.R. 2 became more stable and demonstrated better performance.
GSC Game World owner Maksym Krippa has previously repeatedly spoken about the importance of long-term support for the game and the further development of the S.T.A.L.K.E.R. franchise. Even after the release, the studio continues to invest resources in the project, which, in particular, allowed for such a large-scale engine update.
Why GSC has no plans to return to X-Ray
The studio is not even considering a return to X-Ray, which was used in the previous parts of S.T.A.L.K.E.R.. The studio has not even considered it. Maria and Yevhen Grygorovych noted that the main problem with such a decision is the lack of specialists who have sufficient experience working with this engine.
There is another reason to stay on the Unreal Engine. Maria believes that working with a standardized engine gives GSC developers broader opportunities for their future careers. It would be much more difficult for specialists to find a new job if their experience was limited only to the studio’s own engine.
At the same time, GSC does not believe that Unreal Engine is a universally correct choice for everyone. Maria emphasized that each company must independently determine which tool best meets its needs. For GSC, Unreal became such a solution.
“An engine is a tool,” Yevhen Grygorovych concluded. “You choose the right tool for the right project.”