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DirectX 12: Hype Or Hypnotic?










              ack in June 2015, we took an in-depth
           B look at Microsoft’s DirectX 12, the
           latest gaming-focused API that’s exclusive
           to Windows 10. Because that OS went
           on sale a month after that article’s
           publication, our coverage was necessarily
           limited to an analysis of the “on-paper”
           benefits of DX12. To truly experience
           DX12’s streamlined graphics pipeline and
           better multithreaded scaling, games that
           leverage the new API need to become
           available, and as we learned from DX10’s
           disastrous face-plant, (which may owe
           its failure more to its Windows Vista
           exclusivity than to any one feature or
           flaw), those games may never materialize.
             Fast forward to today: We’re happy to
           report that there are a decent number of
           DX12-exclusive games and even more that
           had optional DX12 running modes either
           at launch or patched in shortly thereafter.
           Perhaps most promising of all, the   Will DirectX 12 herald the renaissance PC gamers have been waiting for?
           DX12 games that are currently available,
           including Forza Horizon 3, Gears Of   is the data available to us at the time. As   also something that older DX11-based
           War 4, Star Wars Battlefront, Rise Of   such, it is our goal with this article to   graphics cards from AMD and NVIDIA
           The Tomb Raider, HITMAN, Deus Ex:   document the impact of DX12, if any, to   supported at Win10’s launch.
           Mankind Divided, and Battlefield 1 rank   help you make a more informed decision   DX11 is good at many things, but CPU
           as some of the best games of last year. The   when it comes time to upgrade.   utilization under this API was always seen
           API also currently enjoys hearty support                             as unnecessarily high. One way DX12
           from most modern game engines and   Promises, Promises               solves this problem is through the use of
           numerous publishers. Although we’re still   Before we dig into the numbers, let’s   draw call bundles, officially introduced in
           in DX12’s relative infancy, we’re confident   recap some of the reasons DX12 seems   Xbox One as a part of its modified DirectX
           that it has a bright future.       to be getting off to such a healthy start.   11.x API.  These allow the rendering
                                              From a consumer standpoint, the new   hardware to bundle and cache a series of
           A DirectX 12 Snapshot              API is compelling because it was built   operations likely to be reused. When that
             DirectX 12’s utility to PC gamers is   to be significantly more power-efficient,   series is called for again, it executes with
           a bit of a moving target at the moment.   resulting in better performance for   little to no overhead. Developers can also
           Evolving graphics hardware, OS tweaks,   gamers running even mainstream or   employ descriptor heaps and tables to
           driver improvements, and developer   entry-level components. Features such   store frequently-used resources to further
           support all tend to have a huge impact   as descriptor tables and concise pipeline   spread the workload across the CPU and
           on the performance of a given title at a   state objects, for instance, enable Win10   GPU more efficiently. Command lists,
           given point in its life span. Unfortunately,   to better pair up the graphics hardware   like draw call bundles, are yet another
           anytime we set out to weigh the    with the appropriate DirectX abstraction   feature designed to decrease the number of
           advantages and drawbacks of making a   layer.  This lower-level abstraction   repetitive tasks that the CPU performs. In
           particular upgrade, all we have to go on   is a key component of DX12, but it’s   short, DX12 is born to multithread.



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