Microsoft recently revealed DirectX 12, the next iteration of its graphical API, and there been an on-going discussion in the public domain about it. Can it really increase the Xbox One’s performance as proclaimed by some developers? An API works to increase the efficiency of the GPU, thus ensuring it performs better than before, but does that constitute any viable performance boost?
In a recent tech interview, Digital Foundry spoke to RedLynx’s lead graphics programmer Sebastian Aaltonen about the same, especially since the latter has experience in working with Microsoft GPUs in a low-level manner (with the Trials franchise). Will DirectX 12 provide a substantial difference to Xbox One development?
Aaltonen stated that, “Xbox 360 got a big boost from the low-level graphics API. We managed to hit up to 10k draw calls per frame (at 60fps) in Trials Evolution using the low-level Xbox 360 graphics API, as discussed in our earlier interview. We are eagerly waiting to get our hands dirty with DirectX 12. It’s definitely possible that Xbox One will also get a performance boost from a new low-level API.”
He further emphasized that it would make porting easier, though some work still needs to be done due to the unified memory of consoles. “If we have the same API on both the console and PC, porting and code maintenance will be also easier. However consoles have unified memory and PC doesn’t, so there still needs to be multiple code paths, for example with data streaming from HDD to GPU. Same is true for any CPU+GPU interoperation. If you need to move the data between them, you most likely want to select a different algorithm for PC, because the PCI Express bandwidth and latency are very slow compared to direct unified memory access of consoles.”
DirectX 12 will be introduced in the Holiday season of 2015. Stay tuned for more information on just what it will be capable of in the coming months. In the mean time check out our Xbox One review of Trials Fusion.