Epic Games claims that it has eliminated stutters caused by Pipeline State Objects (PSO) in Unreal Engine with version 5.2 of the engine.
Speaking during a discussion panel that offered an overview of the new features and improvements brought to Unreal Engine 5 with version 5.2, the Director of Graphics Engineering at Epic Games, Juan Canada, stated that he believes him and his team have succeeded in getting rid of PSO related stutters/hitches. He mentioned that the issue has plagued many PC games shipped on Unreal Engine in DX12.
Canada mentioned that his team had begun making improvements in this regard with the arrival of Unreal Engine 5, taking it even further with Unreal Engine 5.1. With version 5.2 of the engine, it’s finally possible to say that PSO related stutters are “pretty much gone”. He further stated that there is a new pre-caching system in place and that the old manual caching system should not be needed anymore “except in really extreme cases”.
He explained that the new system essentially waits for the PSO to be compiled before something is drawn in the scene. In some cases, this will increase pop-in of assets due to the system being required to wait for PSO compilation. Canada stated that developers may need to do some “housekeeping” in order to make sure that the loading stream has enough time to allow PSO compilation.
Canada mentioned that changes have been made to Fortnite’s loading stream in order to extend the wait time so that all PSOs are cached beforehand. According to him, the new system really pays off, as there are no more hitches.
Other new features added to Unreal Engine 5.2 include a Procedural Content Generation (PCG) framework, an improved way of authoring materials known as Substrate, an enhanced virtual production toolset, and the inclusion of a new Machine Learning based Deformer sample.