Mantle [...] is a way to allow multiplatform developers to take their already optimized GCN rendering code [from PS4/Xbox One] and bring it over to the PC. They’ll still have to write Direct3D/OpenGL code for NVIDIA/Intel/ImgTech GPUs, but for AMD GPUs they can go lower and faster, and best of all they already have most of the code necessary to do this. Coming from the consoles to the PC over Mantle should be very portable.
How portable? The answer surprised even us. Based on our conversations with AMD and what they’re willing to say (and not say) we are of the belief that Mantle isn’t just a low level API, but rather Mantle is THE low level API. As in it’s heavily derived (if not copied directly) from the Xbox One’s low level graphics API. All of the pieces are there; AMD will tell you from the start that Mantle is designed to leverage the optimization work done for games on the next generation consoles, and furthermore Mantle can even use the Direct3D High Level Shader Language (HLSL), the high level shader language Xbox One shaders will be coded against in the first place.
Now let’s be very clear here: AMD will not discuss the matter let alone confirm it, so this is speculation on our part. But it’s speculation that we believe is well grounded. Based on what we know thus far, we believe Mantle is the fundamentals of the Xbox One’s low level API brought to the PC.
By being based on the Xbox One’s low level API, Mantle isn’t just a new low level API for AMD GCN cards, whose success is defined by whether AMD can get developers to create games specifically for it, but Mantle becomes the bridge for porting over Xbox One games to the PC. Nothing like this has ever been done before, so quite how it will play out as a porting API is still up in the air, but it’s the kind of unexpected development that could have significant ramifications for multiplatform games in the future.
Of course an API is only as useful as the software that uses it, and consequently AMD has been working on this matter before they even announced Mantle. As AMD tells it, Mantle doesn’t just exist because AMD wants to leverage their console connection, but it exists because developers want to leverage it too, and indeed developers have been coming to AMD for years asking for such a low level API for this very reason. To that end a big part of Mantle’s creation is rooted in satisfying these requests, rather than just being something AMD created on its own and is trying to drum up interest for after the fact.
With at least one developer already knocking on their door, AMD’s immediate strategy is to get Mantle off the ground with a showcase game, all the while focusing less on individual game developers and more on middleware developers to implement Mantle support. In a roundabout way AMD is expecting middleware to become the new level of abstraction for most game developers in this upcoming generation, due to the prevalence of middleware engines. As game developers make ever increasing use of middleware over limited-reuse in-house game engines, downstream developers in particular will be spending their time programming against the middleware and not the APIs it sits on top of, making it easy to work in Mantle support.
Consequently, AMD for their part believes that if they can get Mantle support into common middleware like DICE’s Frostbite engine, then the downstream games using those products will be in a good position to offer Mantle support with little to no effort on the part of the individual game developer. Put in the humongous effort once at the middleware level, and AMD won’t have to repeat it with individual developers.
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Wrapping things up, when AMD first told us about their plans for Mantle, it was something we took in equal parts of shock, confusion, and awe. The fact that AMD would seek to exploit their console connection was widely expected, however the fact that they would do so with such an aggressive move was not. If our suspicions are right and AMD is bringing over the Xbox One low level API, then this means AMD isn’t just merely exploiting the similarities to Microsoft’s forthcoming console, but they are exploiting the very heart of their console connection. To bring over a console’s low level graphics API in this manner is quite simply unprecedented.