Multiple sessions at the upcoming GDC (Game Developers Conference) are teasing the existence of a new, low-level series of APIs coming to both Direct3D and OpenGL. Nvidia has already given several talks on reducing driver overhead in OpenGL (a substantial example of one such presentation is available online), but the input from Microsoft is new.
In fact, as some of you may recall, an AMD executive publicly stated a year ago that there was no “DirectX 12″ on the Microsoft roadmap. Microsoft responded to those comments by affirming that it remained committed to evolving the DirectX standard — and then said nothing more on the topic. Then AMD launched Mantle, with significant support from multiple developers and a bevy of games launching this year — and apparently someone at Microsoft decided to pay attention.
Note: Microsoft has not confirmed “DirectX 12″ as an actual brand name for the next-generation of DX technology. It’s used here as the most logical version number.
The GDC webpage for one of the DirectX talks states ” You asked us to bring you even closer to the metal and to do so on an unparalleled assortment of hardware. You also asked us for better tools so that you can squeeze every last drop of performance out of your PC, tablet, phone and console. Come learn our plans to deliver.”.
The Mantle Angle
We’ve spoken to several sources with additional information on the topic who have told us that Microsoft’s interest in developing a new API is a recent phenomenon, and that the new DirectX (likely DirectX 12) will substantially duplicate the capabilities of AMD’s Mantle. The two APIs won’t be identical — Microsoft is doing its own implementation — but the end result, for consumers, should be the same: lower CPU overhead and better scaling in modern titles.
This has already been read in several circles as to be the death knell for AMD’s custom API, but such claims are short-sighted, for multiple reasons. First, there’s the fact that DirectX 12 is almost certainly 12-18 months away. Second — and equally important — there’s the fact that Microsoft has been locking DirectX releases to Windows versions. DirectX 11.1 is only available on Windows 8; DirectX 11.2 is only available on Windows 8.1. Microsoft has every reason to synchronize the launch of DX12 with its next version of Windows — and if it follows its typical MO, that means DirectX 12 will be most likely be a Windows 9 exclusive.
Microsoft, of course, doesn’t have to play its cards that way, but if it does, Mantle may remain relevant as a cross-platform alternative for extending close-to-metal benefits across the gaming stack. Of course, OpenGL may or may not be capable of performing the same tasks in the same time frame — but less is known on that front. Hardware support could also complicate matters — if DirectX 12 closely maps to Mantle, it’s possible that today’s GCN GPUs will still support it. Alternately, if it doesn’t, then Mantle may become the preferred option for ensuring broad backwards compatibility.
And if Mantle is ultimately subsumed by DirectX — so what? When I first talked to AMD about the next-generation API at APU13, the developers candidly told me that the long-term goal was to get Microsoft and the Khronos Group in charge of OpenGL to adopt a Mantle-like architecture. The entire point of Mantle was to spur game development and drive the adoption of a better standard.
AMD has released an official statement on the matter, saying:
Yesterday several articles were published that reported that DirectX and OpenGL are being extended to include closer-to-metal functionality and reduced CPU overhead. AMD supports and celebrates a direction for game development that is aligned with AMD’s vision of lower-level, ‘closer to the metal’ graphics APIs for PC gaming. While industry experts expect this to take some time, developers can immediately leverage efficient API design using Mantle, and AMD is very excited to share the future of our own API with developers at this year’s Game Developers Conference.