Slightly Mad Studios Creative Director Andy Tudor discussed bottlenecks their team encountered while optimizing Project CARS to the Playstation 4, particularly in terms of the system’s CPU threads and GPU compute units.
Tudor pointed out that the single-core speed in the system is too slow compared to a high end gaming PC, so they have to split even the smallest tasks into two to three millisecond chunks. The challenge comes here, in splitting their rendered across different threads, so that they each become fine grained.
The bottleneck mainly comes up when building command lists. They can split these up in the PS4 to as much as four cores in parallel. Other bottlenecks come up in the form of memory copying, which apparently becomes a problem even after using the systems’ LCUE. The LCUE was a driver-level shader resource update engine. This engine improved CPU performance and is integrated in the SDK.
If you’re like me, these details don’t mean anything to you either, but I appreciate Tudor’s honesty regarding what Slightly Mad Studios had to work with. It should not be disputable that you can build a high-end PC now that will beat the Playstation 4 performance wise, but they are working on making Project CARS as good as it can be on the system, as they had promised for the Wii U.
Tudor has also expressed interest in the system’s Share feature, noting that their preview videos are getting millions of views as it is, so this is definitely something that they want to see used for Project CARS.
Project CARS is coming the second half of 2014 to Playstation 4 and Wii U, as well as Xbox One, Windows and Steam.