Our recent editorial on adoption of Windows 8.1 by PC enthusiasts concluded saying "...and Microsoft isn't stopping with its innovations that will get increasingly out of reach for Windows 7 users." It looks like the first of such innovations is DirectX 11.2. Microsoft revealed that the latest version of its multimedia API will require Windows 8.1 on the PC, and comes built into its next-generation Xbox One console. With this, Microsoft established that you will need Windows 8.1 or later, to access future versions of DirectX.

Microsoft has often used the tactic of limiting DirectX versions to certain versions of Windows, often citing driver-model changes, to force PC enthusiasts to either upgrade, or lag behind in PC technology, and in the past it worked. Windows XP capped out at DirectX 9.0c, forcing gamers to upgrade to Windows Vista, to experience cutting-edge games of the time, such as "Crysis," with new visual effects that DirectX 10 brought to the scene. DirectX 11.0 had the unique distinction of spanning across Windows Vista and Windows 7. DirectX 11.1 was exclusive to Windows 8 and above, as it required WDDM 1.2 (Windows display driver model). The Direct3D component of the API didn't bring anything substantial to the scene. With Windows 8.1, Microsoft is introducing DirectX 11.2, it requires WDDM 1.3, which the operating system introduces. Since Windows 8.1 will be offered as a free upgrade to current Windows 8 users, it's effectively the Windows 7 user-base, that's being asked to take a hike.

DirectX 11.2 introduces a few new Direct3D features that could matter to games. The "D3D tiled resources" feature is analogous to OpenGL MegaTexture, implemented on id Software's "Rage." The feature offers a better alternative to the current model of streaming textures as a 3D scene is being rendered; by letting developers use larger textures that are fewer in number. Portions of these giant monolithic textures would be accessed by an application, as they become relevant to the scene being rendered. The complete texture needn't be loaded to the memory. In essence, mega-textures heralds a sort of virtual memory system to GPUs, and shifts the focus from increasingly larger video memory to faster memory.

With Windows 7 user-base being cut out from DirectX 11.2, game developers may think twice before spending time to implement D3D tiled resources, but there's also Xbox One to consider. DirectX 11.2 is at the heart of the console, and Microsoft could recommend developers to take advantage of tiled resources, to optimally use the console's limited hardware resources. That could hasten the adoption of DirectX 11.2 by developers, on the PC front.

Among the features DirectX 11.2 introduces are:

HLSL shader linking
Inbox HLSL compiler
GPU overlay support
DirectX tiled resources
Direct3D low-latency presentation API
DXGI Trim API and map default buffer
Frame buffer scaling
Multithreading with SurfaceImageSource
Interactive Microsoft DirectX composition of XAML visual elements
Direct2D batching with SurfaceImageSource

原文網址 http://www.techpowerup.com/186671/d...d-xbox-one.html

是要人換win8.1嗎???