Brad Wardell: DX12 resolving Resolution Issue On Xbox One; Replacing eSRAM API

Stardock Studios are developing on Ashes of Singularity, one of the first games that will be supporting DirectX 12. Brad Wardell at stardock studio spoke about DirectX12 on how will it improve the Xbox One’s hardware performanceespecially given it’s static hardware nature compared to a PC.

“It won’t have the same impact,” Wardell states. “There are a couple of things that are important in DirectX1 2 for Xbox One developers though. First of all Xbox performance is completely the result of the eSRAM feature and there isn’t a true or false thing with regards to one using eSRAM. You could use it well or you could use it poorly or somewhere in-between, and their API which is the current DirectX11 extension for the Xbox is really crappy for dealing with the eSRAM. That has resulted in what’s called Resolution Gate.”

Wardell discovered that Microsoft moving away with the older API that uses to fetch data to and from eSRAM and replacing it with the API that comes with DX12 which Wardell claims it will bring in huge changes.

“I’ve never heard Microsoft just come out and, I mean they should just really come out and explain to people why they’re having problems getting games to run at 1080p. But maybe they don’t think their users will understand, basically it has to do with developers aren’t making effective use of the eSRAM API. So in DirectX12 they actually threw it away, they threw away the crappy one in DirectX11 and they’re replacing it with a new one. So that’s pretty huge.”

“They also released a new tool, it’s this optimization tool that will actually algorithmically try to come up with an optimization for the developer. So instead of the developer trying to hand set-up what uses eSRAM, they have their own app to try and do as much of it for them as they can. Third, DirectX11 still serializes stuff from the developer to the GPU. It is low-level but the fact is as low-level as it, it’s still serializing a lot of GPU calls. So it won’t be anywhere near…you won’t get the benefit on Xbox One that you’re getting on the PC.”

“It’s  completely different but you are going to get a substantial benefit. The part I think that users will care about is that it should address the resolution stuff for most people. That’s what I think is the most glaring thing that people are upset about. But it won’t do anything magically. The developers still have to use it, it’s not like your old games will magically be faster.”

“Yeah, it should do that [on resolving the resolution issues due to eSRAM], because in DirectX11 it’s really a pain to make good use of the eSRAM. Whereas supposedly in DirectX12 and this is all theory, I haven’t used it myself but the new API is supposed to make it alot easier to optimize your use of the eSRAM memory.

“The API is there for me to use as a tool for the piece of hardware. And the one that was in DirectX11 was not easy, it was a very trial and error process to make use of the eSRAM. In DirectX12 they’ve tried to make it easier to make use with and the easier it is to use, the more likely you’re going to get developers who optimize for it correctly.”