Mantle would be a good thing for AMD if all three platforms support the API.
While speaking on a panel at Nvidia's "Way It's Meant to be Played" event in Montreal, John Carmack talked about AMD's Mantle API, stating that it would be very "powerful" for AMD if Sony and Microsoft decide to adopt the technology. If not, and Mantle remained a PC-only tech as AMD now describes, then he would have very little interest in it.
"Mantle is unique. AMD has talked many times in the past about doing 'close to the metal' architectures, and it only became interesting because of their dual console wins," Carmack said. "The landscape does matter because they have both major console wins with similar architectures that you can get on the PC."
"If it was just a way to do, on the PC, lower-level [coding] I couldn't have cared less," he added. "If I was still doing all of the major tech coding, I probably would not be embracing Mantle right now. But there would be days where it would be extremely tempting."
In addition to Carmack, Epic Games' Tim Sweeney and DICE's Johan Andersson were on the stage answering questions as well. Later during the talk, all three were asked about their thoughts on other developers following AMD's lead by creating their own APIs. All three agreed that it would be a bad idea.
"It's the wrong direction for the industry to go," Sweeney answered. "If you'd ask me if I'd much rather have a low level API for accessing the GPU, the answer is yes. But five of them, for different hardware, vendors and operating systems? Absolutely not."
Andersson said it would be a bad future if Nvidia, Intel and Qualcomm developed their own APIs. Carmack gave an unequivocal no. "It would be a horrible mistake if Nvidia got panicked by this and made some lower level API as you already have good low-level access through Nvidia's GPU extensions," said Carmack.
Previously, wording provided by AMD led to the assumption that the Mantle API would address not only many Graphics Core Next-based GPUs and APUs on the "metal" level, but the GCN-based APUs found in the Xbox One and PlayStation 4. This would, in theory, allow developers to create games for all three platforms more easily, and implement similar AMD-driven features across all three versions. Microsoft said the Xbox One wouldn't support Mantle, and AMD quickly followed up saying that the API was strictly for PC gaming development.