Windows Graphics Overview.ppt

Windows Graphics Overview David Blythe ArchitectWindows Graphics Gaming Technologiesdblythe @ Microsoft Corporation Session Outline Windows Graphics Big Picture Windows codenamed Longhorn Display Driver Model Basic, Advanced driver models Graphics APIs Legacy, Direct3D9, Windows Graphics Foundation, OpenGL Desktop Window Manager Content Protection Protected Video Path Glitch-Free Media Support Windows Graphics Foundation 2.0 Windows Graphics in Longhorn Longhorn Display Driver Model Graphics Just Works Fundamental principle New driver model delivers: Stability Security Availability (virtualization) Performance Staged introduction of driver model Basic model supports current hardware (planned for Longhorn) e.g., pre-Longhorn hardware Advanced model utilizes new hardware features (post-Longhorn) More efficient virtualization Old XP driver model still supported for compatibility No new features Stability Security Application graphics state isolated from other applications Surface data (textures, render targets, etc) Virtual address spaces Current rendering state Shaders, etc Command stream is validated Prevents access to unauthorized resources e.g., another application’s surfaces Prevents illegal command streams Avoid sending bad commands to hardware But, still have a watchdog timer Time out if not making forward progress Basic driver model does sw validation in kernel Advanced driver model does hw validation Virtualization Allow multiple applications to “time slice” the graphics hardware Scheduler determines which commandstream to run Basic driver model schedules batches Batch = sequence of commands submitted by application Batch can’t be interrupted once started Advanced driver model schedules contexts Batches accumulated in application context Can interrupt a context and run a different one More responsive to input changes (new work, priority changes) Better user experience Virtualization Memory manager determines which memory resources need to be resident