As everyone thinks now, Windows 7 is actually an improved version of Windows Vista. Windows 7 has done a lot of improvement work on the basis of Windows Vista, and has added many new features. Compared with its predecessor, XP provides a very big improvement. However, on the one hand, these improvements are too large, and users and even corresponding software vendors (such as DirectX 10 application developers) cannot fully accept it. On the other hand, due to the lack of features. Fully equipped, Vista's performance is not as good as imagined. By the way, Windows 7, including the operating system itself, software vendors and users are ready, so it is not difficult to understand the response better than Vista.
The graphical interface has always been the core of the Windows system, and starting with ghost xp, Windows will begin to provide a graphical desktop graphical interface as a point, not only because Vista and 7 desktop itself is a 3D application. But because Vista and 7 can better play the role of graphics acceleration hardware. From Windows Vista to Windows 7, the combination of operating systems and GPUs is getting closer.
Although people often hear that Windows 7's big update lies in a DirectX 11.0 API, for Windows graphics architecture, although DirectX is also important, it is not all. A graphics architecture includes how to use the GPU to accelerate a variety of graphics applications (2D, 3D, printing, etc.), how to display to the final display device, and device detection and control. Window 7's update in graphics architecture mainly includes the following aspects:
WDDM 1.1: New Driver Model
DirectX 11: Updated Direct3D 11, and related new Direct2D API
DXVA-HD: HD video playback Accelerate
display device connection and configuration
color management
high DPI output and readability
multi-GPU system
joint display adapter (also known as joint rendering)
Next, will be these Improvements are briefly introduced.
Windows 7 Core Graphics Architecture
Windows applications use a variety of APIs such as GDI (Graphics Device Interface), Direct3D, OpenGL, and system graphics components, while system components pass WDDM. (Windows Display Driver Model, also known as Longhorn Display Driver Model) interacts with hardware. From Vista, Windows uses a new driver model different from XPDM used by XP: WDDM, the driver model used largely determines The graphical characteristics of a system. Vista uses a version of WDDM of 1.0, while an improved version of Windows 7 is WDDM 1.1.
The changes brought by WDDM 1.1 are quite a lot. Let's take a look at the changes of WDDM 1.0 relative to XPDM, that is, the change of Vista relative to XP
XPDM: non-synthetic model
WDDM: synthetic model
In the vertical synchronization puzzle XP/Vista and 3D performance test, I explained the difference between the Ghost xp model. Under the WDDM model, all the applications generated display will end up in DWM (Desktop Windows Manager, desktop). The window manager is composited into a single final output image, so it gets better display (naturally synchronized with all programs), extra effects (thumbnails, zoom) and can support a larger left side, but original WDDM 1.0 only implements this large architectural transformation, and the details are still not perfect:
Under Vista, GDI (the usual 2D window API, in addition to many other graphics operations using GDI) and DirectX ( 3D application API) has different processing methods: Direct3D is hardware accelerated, while GDI is not (GDI is hardware accelerated in XPDM), so Vista users will feel slower than XP on some graphics programs; The GDI application is first processed by the CPU software into the system memory, and then transferred to the GDI memory area allocated by the graphics card driver (also in the system memory), and then the DWM is responsible for synthesizing the screen output to the display
Windows 7, GDI Get hardware acceleration (see below) —— but when using GDI and Direct3D APIs together, GDI still can't hardware acceleration, but GDI output directly to the driver's GDI memory area, reducing one step and reducing Memory consumption (also valid for mixed Direct3D APIs); obviously, mixing food APIs for graphical programming is not a good idea (of course, using both GDI and Direct3D means that this is an old, window-mode 3D application. Old 3D games like Windows mode)
Old WDDM 1.0 handles GDI applications as mentioned before
In the Windows 7 WDDM 1.1 model, separate GDI will be hardware accelerated by WDDM and GPU At the same time, it is output to DWM through the GDI memory area. In actual operation, most of the window operations become smoother than Vista. Work faster (most 2D applications use the GDI API, because GDI includes too much content, so it must be compatible; about GDI, there is related content later)
Windows XP Direct3D/GDI driver architecture
Windows Vista core graphics architecture, a lot more rich than XP
Windows 7 core graphics architecture, the old GDI/GDI+ is still supported separately, but Windows 7 provides a new implementation of their corresponding functions Compared to Vista's DirectX 10, Windows 7 comes with DirectX 11, and WDDM 1.0 to 1.1 changes. DirectX 11's version number indicates a greater change. Windows 7 DirectX 11 changed the previous working mode, upgraded Direct3D 10.1 to Direct3D 11, and re-divided the work of GDI/GDI+, which was previously unable to accelerate hardware by Vista, and introduced the new Direct2D and DirectWrite APIs:
Previous Most graphics operations are done by Diredt3D and GDI/GDI+ (in addition to a WIC—— Windows Image Component, which manages scanning, printing, and graphics decoding), while in Vista, GDI is not hardware accelerated —— Therefore, Vista appears to be very slow. In Windows 7, in addition to hardware acceleration through changes in the WDDM model, they are reclassified to Direct2D (2D Acceleration), DirectWrite (Text Processing), and DXGI 1.1 (for application-oriented applications). Device Control), these new APIs or newly assigned APIs have hardware acceleration. For example, Direct2D actually accelerates through Direct3D 10:
Direct2D:
Hardware-accelerated real-time mode 2D graphics API It has high performance and quality in 2D geometry, bitmaps and text. The Direct2D API is designed to interoperate with GDI, GDI+ and Direct3D
DirectWrite:
DirectWrite provides high quality text rendering, outline fonts with independent resolution, full Unicode text and layout support. When using Direct2D, DirectWrite is hardware accelerated.
When the system does not support Direct3D 10, Windows 7 will use D3D9 to complete the work through an additional 10Level9 software layer. Obviously, for the best efficiency, you need to use Direct3D10 graphics card, because Windows 7 DWM is based on Direct3D. 10
Digital Anti-Aliasing: DirectWrite Effect
Direct3D 11
Windows 7 with Direct3D 11 is a superset of D3D10, which is characterized by support for running on Direct3D9 and Direct3D10.1 hardware, in fact, DirectX 11 will provide Vista support, instead of just supporting Vista as it was when Direct 10 came out, it will not be compatible with previous generation systems, which has led to a slow transfer of software developers to DirectX 10. DirectX 11 supports multiple hardware platforms and multiple operating system features to make it more acceptable. At the same time, Direc3D 11 itself has a lot of improvements, there will be a special article discussion (planned), here first talk about Windows 7 to improve the overall graphics operation, through more GDI /GDI + into the DirectX system to obtain hardware acceleration, The performance of the graphical interface will get better and better (of course, this requires software vendors to write with the new Direct2D/DirectWrite). Microsoft wants to build all graphics operations on top of DirectX.
Recovering hardware acceleration through the missing GDI hardware acceleration in Vista, and the performance is faster; future graphics card manufacturers will no longer need to provide GDI acceleration
display technology
Windows 7 support one The range of display technologies, including digital output as native output (supports HDMI and DisplayPort, while old VGA analog output is recommended for deprecation), Windows 7 restores support for more content sources such as Blu-Ray, JPEG-XR, HDR pictures, etc.
Windows 7 uses the default sRGB color space as a uniform workflow for all devices, but the accuracy is increased to 30 bits — — each color channel is increased by two; Windows 7 supports up to 48-bit scRGB mode. High precision + extended range + high dynamics
WDDM 1.1 requires driver support BGRA, BGRA is the fastest color format
Display device connection and configuration
In ghost xp, all applications are in a unified The virtual desktop shows that the virtual desktop resolution is 64Kx64K (65536x65536)
The virtual desktop is divided into different views according to the display, each view corresponds to one adapter; one adapter does not mean one graphics card, one graphics card connects multiple displays In the meantime, it contains multiple adapters. Similarly, a single monitor connected to SLI or CrossFireX means it is a single adapter (joined from Vista, called the Linked-Adapter feature). However, under Vista, Unable to use multiple graphics cards from different GPU vendors, while Windows 7 can
Under the LDA configuration, the xp system downloader interface roams in different outputs. Basically transparent, called Dynamic adapter switching dynamic adapter switching
Under multi-display, Windows 7 provides a new global shortcut function: Win + P, you can quickly set the multi-monitor working state, this shortcut is originally Designed specifically for projector applications
In general, Windows 7's graphics architecture is more complete than Vista, and applications are more convenient. The most obvious is the change of the GDI API. Now the GDI application has also achieved hardware acceleration, just like the xp, it can only be processed by the processor under Vista, so users can feel the daily application will be more smooth.