A “closer to the metal” version of Direct X is in the works, and while AMD says it supports such efforts, what does it mean for the future of PC Gaming?
Microsoft may be looking to capitalize on AMD’s struggle with Mantle with its next version of DirectX by integrating vendor specific extensions to allow Mantle-like low level access to the hardware.
When AMD first announced the Mantle API last year at its #gpu14 event in Hawaii, the company said it would give developers low level access to GCN hardware where ever it was present be it PC or console. Shortly after Microsoft and Sony denied this would be the case for their consoles, AMD’s PR backtracked and said Mantle would provide developers console like experience when developing code. Since then AMD’s problems with Mantle have not let up. The Mantle patch for Battlefield 4 was months late, and the other big Mantle title, Thief, won’t launch with Mantle enabled. When Battlefield 4‘s Mantle patch finally launched the performance boosts were in the single digits and far from revolutionary.
A number of presentation abstracts from Microsoft speakers at next month’s Game Developer’s Conference have pointed towards a Direct X update in the works that would allow lower-level hardware access. Consider the synopsis of this talk hosted by Anuj Gosalia, Development Manager for Windows Graphics, titled “DirectX: Evolving Microsoft’s Graphics Platform”:
For nearly 20 years, DirectX has been the platform used by game developers to create the fastest, most visually impressive games on the planet.
However, you asked us to do more. 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.
In another one, titled Direct3D Futures, Microsoft’s Max McMcullen, promises to “discuss future improvements in Direct3D that will allow developers an unprecedented level of hardware control and reduced CPU rendering overhead across a broad ecosystem of hardware.”
All this is not to say that Microsoft is interested in developing a Mantle clone with its next version of Direct X. Only AMD can develop something that has such intimate access to the GCN core since they know the hardware best. But while Microsoft won’t be offering Mantle, it is capitalizing on what Mantle can do — lower level access to hardware — and what it can’t do — entice developers and have them deliver Mantle to games on time.
In response to all of this AMD has released a defensive statement: 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.
But not everyone is convinced that the “closer to metal” access that Mantle provides is necessary for overhead-killing performance boosts. In October, John Carmack tweeted, “9x draw calls is credible over stock D3D, but Nvidia OpenGL extensions can give similar improvements.” He followed this up in November at an Nvidia event by saying, “Mantle only became interesting because of their dual console wins.”
While Carmack didn’t mention this, draw calls are not an accurate metric to gauge performance. Draw call requirements can differ widely from title to title depending on the payload.
It will be interesting to see how DirectX evolves with a push in this “low level” direction. For all this talk of the evolution of DirectX, one can’t help but remember that it was almost a year ago Roy Taylor — who much to the chagrin of AMD’s PR corps has very interesting insights into the hardware arms race — said DirectX as we know it is on its way out.
“There will be no DirectX 12. That was it. As far as we know there are no plans for DirectX 12,” he said to a German publication called Heise. “If this should not be, and someone wants to correct me – wonderful.”
For its part, Microsoft didn’t outright deny Taylor’s claims and only responded by saying, “We have absolutely no intention of stopping innovation with DirectX.”
Perhaps given the change and evolution Microsoft is planning for its API they will abandon the DirectX numbering convention and Taylor will be proven right after all.