Windows Display Driver Model (WDDM, also WVDDM during the Vista time-frame) is the graphic driver architecture for video card drivers running Microsoft Windows versions beginning with Windows Vista.
It is a replacement for the Windows XP display driver architecture aimed at enabling better performance graphics and new graphics functionality.
WDDM provides the functionality required to render the desktop and applications using Desktop Window Manager, a compositing window manager running on top of Direct3D. It also supports new DXGI interfaces required for basic device management and creation. The WDDM specification requires at least Direct3D 9-capable video card and must implement the device driver interfaces Direct3D 9Ex runtime in order to run legacy Direct3D applications; it may optionally implement runtime interfaces for Direct3D 10/10.1 and higher.
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