Windows vista display driver model wddm

WDDM drivers improve operating system stability and security because less driver code runs in kernel mode where it can access system address space and possibly cause crashes. 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 the display driver must implement the device driver interfaces for the Direct3D 9Ex runtime in order to run legacy Direct3D applications; it may optionally implement runtime interfaces for Direct3D 10 and higher Wikipedia. Dual View is available for the installer.

I am trying to install WDDM 1. Driver Model is available starting with a pre-requisite for D3D I installed and higher being handled at. Windows 8 introduced version 1. I was reading the WDDM 1. The WDDM 2. The first is related to general devices such as chipset, audio DSP, IDE controllers etc, while the second is related to graphics cards only from Windows Vista and latter versions of Windows. But i did not find any example code or sample which explains the following WDDM 1.

This section discusses requirements, while the Mobile Intel offer. With Windows XP connecting a laptop to a projector can prove to be a multistep process, where each step might be totally different from one laptop vendor to another.

In Windows Vista, this process of connecting to an external display or projector is greatly simplified. When an additional external display or a projector is connected to the display adapter, WDDM detects this new state instantly and automatically notifies the Transient Mobility Manager TMM module, which is the underlying technology for the new Windows Vista External Display wizard.

The wizard makes it simple to extend or clone the desktop to the second display device. In Windows XP, Hibernate causes the contents of system memory to be saved to the hard disk and the system to be powered off; Standby causes the contents of memory to be preserved with a small amount of power, while the remainder of the system is powered off.

However, in Windows Vista, 'Hybrid' Sleep causes the contents of system memory to be saved to the hard disk and the system placed into Standby at the same time. Therefore, the system is able to resume from system memory extremely fast—in less than 2 seconds for Windows Premium-capable PCs. However, if the battery drains fully or a power loss causes the contents of system memory to be lost, the system can resume from the hard disk.

WDDM implements a much more functional graphical resource management. Windows Presentation Foundation is the next generation of the Windows client development platform for user interface, documents, graphics, desktop-based, and connected applications, as well as content.

It enables a wider spectrum of developers to harness the power of the GPU, without necessarily having to be aware of low-level graphics programming constructs. It is now easier for designers and developers to build user interfaces and content that give customers a richer and more engaging experience.

As a result we will soon see a new generation of applications, both local and Web-based, that provide more engaging experiences, better visualization of data, and greater improvements to the reading experience. WDDM provides the functionality required to render the desktop and applications using Desktop Window Manager, a compositingwindow 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 the display driver must implement the device driver interfaces for the Direct3D 9Ex runtime in order to run legacy Direct3D applications; it may optionally implement runtime interfaces for Direct3D 10 and higher.

WDDM drivers enable new areas of functionality which were not uniformly provided by earlier display driver models. These include:. In the context of graphics, virtualization means that individual processes in user mode cannot see the memory of adjacent processes even by means of insertion of forged commands in the command stream. WDDM drivers allow video memory to be virtualized, [6] and video data to be paged out of video memory into system RAM.

In case the video memory available turns out to be insufficient to store all the video data and textures, currently unused data is moved out to system RAM or to the disk. When the swapped out data is needed, it is fetched back. Virtualization could be supported on previous driver models such as the XP Driver Model to some extent, but was the responsibility of the driver, instead of being handled at the runtime level.

The runtime handles scheduling of concurrent graphics contexts. This differs from native threads on the CPU where one task cannot be interrupted and therefore can take longer than necessary and make the computer appear less responsive. A hybrid scheduling algorithm between native and light threads with cooperation between the threads would achieve seamless parallelism. It is important to note that scheduling is not a new concept but it was previously the responsibility of individual driver developers.

A Direct3D graphics surface is the memory area that contains information about the texturedmeshes used for rendering a 2D or 3D scene. Sharing textures between processes before WDDM was difficult, as it would have required copying the data from video memory to system memory and then back to video memory for the new device.

If a WDDM driver hangs or encounters a fault, the graphics stack will restart the driver. Drivers under Windows XP were free to deal with hardware faults as they saw fit either by reporting it to the user or by attempting to recover silently. With a WDDM driver, all hardware faults cause the driver to be reset and the user will be notified by a popup; this unifies the behavior across vendors. Previous drivers were fully implemented in kernel mode, whereas WDDM is implemented partly in user mode.

If the user mode area fails with an unrecoverable error, it will, at the most, cause the application to quit unexpectedly instead of producing a blue screen error as it would in previous driver models. WDDM also allows the graphics hardware to be reset and users to update drivers without requiring a reboot. The new driver model requires the graphics hardware to have Shader Model 2. It also requires some other hardware features; consequently some SM 2.

One of the limitations of WDDM driver model version 1. If a multi-monitor system has more than one graphics adapter powering the monitors, both the adaptors must use the same WDDM driver. If more than one driver is used, Windows will disable one of them. WDDM 1. Since the desktop and application windows managed by DWM are Direct3D applications, the number of open windows directly affects the amount of video memory required. Because there is no limit on the number of open windows, the video memory available may prove insufficient, necessitating virtualization.

As the window contents that DWM composes into the final desktop are generated by different processes, cross-process surface sharing is necessary. Though this is true for Microsoft's implementation of a composited desktop under Windows Vista, on the other hand, a composited desktop need not theoretically require a new display driver model to work as expected. The approach Microsoft attempted was to try to make sure WDDM was a unified experience across different GPUs from multiple vendors by standardizing their features and performance.

The software features missing from other driver models could be made immaterial by extensions or if a less restrictive or simply different driver model was in place.

Hybrid Sleep, which combines hibernation and sleep mode functionality for enhanced stability in the event of power failure, also requires WDDM. New features include: [10]. DXGI 1. Windows 8 includes WDDM 1. Other major features include preemptive multitasking of the GPU with finer granularity DMA buffer, primitive, triangle, pixel, or instruction-level , [29] reduced memory footprint, improved resource sharing, and faster timeout detection and recovery.

Windows 8. This lead Microsoft to rewrite the graphics driver system during the development of Windows Vista. The more efficient WDDM graphics architecture was the result. This allows Windows users to run multiple graphics intensive applications at the same time. It also simplifies graphics programming, making it easier for 3D game developers to take fully advantage of a system's GPU. Additionally, the WDDM offers improved stability by detecting when the driver hangs and restarting the display driver instead of requiring a full system restart.

Windows 7 includes WDDM 1.