What is DirectX 10

A primitive is one level higher than a vertex at a level, and it consists of one or more vertices. A primitive consisting of a single vertex is called “point", the primitive consisting of two vertices is called "line"; the primitive consisting of three vertices is called "triangle" ; Geometric rendering units support multiple primitive types such as points, lines, triangles, lines with adjacent points, triangles with adjacent points, and can handle up to six vertices at a time. With rich primitive type support, the geometry rendering unit allows the GPU to provide finer model details.

geometric rendering unit gives GPU to create new geometry of the object itself, the magical ability to add content to the scene. The flexible processing power makes the GPU more general. In the past, many of the work that must be done by the CPU can now be handled by the GPU. As a result, the CPU has more time to deal with artificial intelligence, addressing, and so on. What's even more surprising is that the geometry rendering unit also makes it easier to add physical operations. DirectX 10 can create physical boxes and simulate rigid objects, and physics is expected to gradually become popular under its leadership. It is foreseeable that with the weapon of geometric rendering unit, the performance of the graphics card will make a qualitative leap, and we will also experience the game with smoother speed, more beautiful picture and more detailed plot.

Improved API and Driver Power

We know that every game character, weapon and scene is an Object in a 3D program, and every frame of the game screen may appear. Hundreds of Objects. When the graphics card is working, each Object is transferred from the application to the API interface, and then reaches the graphics card through the graphics driver. In the existing DirectX system, any Object operation or rendering will result in additional consumption of system resources. The more Objects in the game, the longer the transmission time will be, and the more additional consumption will be caused. According to statistics, when the existing DirectX 9 graphics chip is working, only 60% of the performance is used to calculate 3D programs, and the remaining 40% of the computing power is wasted!

In order to change this situation, DirectX 10 The dynamic indexing function is adopted in the rendering program, the Object is automatically loaded by the driver, the data can be classified and continuously input, so that the amount of data transmitted in a single transmission is increased, thereby greatly reducing the extra time. By introducing new APIs and drivers, DirectX 10 boosts the performance of graphics chips to 80%. The performance of the graphics card has been greatly improved without increasing the hardware cost of the graphics card.

Parallel Engine Support Technology

In order to improve the efficiency of multi-block graphics collaboration, Microsoft proposed the concept of "Parallel Engine Support" in DirectX 10, which can The data required by the two GPUs is separately transmitted to the two corresponding GPUs. The frame rendering will be completely controlled and configured by the driver, and the working strength of the two graphics cards can be well balanced. In the current mode of operation of the master-slave card, the master card must judge the card frame and the number of renderings. After the introduction of the parallel engine support technology, the concept of the master-slave card will disappear, and the cooperation power of two or even multiple graphics cards will be fully reflect.

Unified Rendering Architecture

The biggest innovation in DirectX 10 is the Unified Shader Architecture. At present, various graphics hardware and APIs adopt a separate rendering architecture, that is, vertex rendering and pixel rendering are performed independently. The former task is to construct polygon vertices containing three-dimensional coordinate information, and the latter is to convert these vertices from three-dimensional to two-dimensional. In this way, the scene of "3D" can be displayed on the screen by visual spoofing. Correspondingly, there are also special vertex rendering units and pixel rendering units in the GPU to perform these two tasks respectively (the number of the two rendering units is not equal due to the different workload, the vertex rendering unit usually only has 1/of the pixel rendering unit) 3~1/2). In the past few years, this discrete design has contributed to the development of computer graphics.

However, Microsoft believes that this separate rendering architecture is not flexible enough. Different GPUs have different ratios of pixel rendering units and vertex rendering units. Software developers must consider this ratio when writing code, which is greatly Limits the space that developers can freely play. In addition, different graphics games or software have different requirements for pixel rendering and vertex rendering, resulting in underutilization of GPU computing resources. To this end, Microsoft proposed the idea of ​​a unified rendering architecture in DirectX 10: performing different types of rendering programs on rendering units of the same physical type. In other words, using only one rendering unit allows it to perform vertex rendering, pixel rendering, and even geometric rendering. In this way, the rendering unit can be used to the maximum extent, reducing the situation of resource idle. Currently, the Xbox 360's display chip Xenos uses a unified rendering architecture. The chip has a total of 48 rendering units, all of which can be used for vertex rendering or pixel rendering without a fixed allocation ratio. In addition, ATI intends to adopt a unified rendering architecture in the new generation of R600 chips.

Of course, the unified rendering architecture is not perfect. Relative to vertex rendering, pixel rendering will face the material delay caused by the large-scale use of textures, which is an urgent problem to be solved by the unified rendering architecture. However, one thing is certain, under the strong promotion of Microsoft, the unified rendering architecture is the general trend. Other references "What is DirectX" http://www.45it.com/xianka/200811/20207.htm