Research On Programing Pixel Shader

Nowadays 3-D graphics technology has been widely applied in various fields such as movies and games, effectively improving the visual effects of images. With the rapid development of consumer electronics, 3-D graphics technology has also been widely used in current handheld devices like 3-D operation interface, 3-D games, 3-D GPS navigation and so on. These functions are mostly analog implementation of software on generic processor, which causes large CPU load, high power consumption and low-quality rendering. Besides, this way of implementation is rather hard to realize graphic rendering in real time.Therefore, the urgent need for 3-D high-definition graphics rendering on mobile devices has attracted wide attention. Although some simple 3-D graphics rendering functions can be implemented on mobile devices through software simulation, this rendering method still has some drawbacks like occupying too much CPU resources and increasing CPU power consumption for its complicated rendering algorithm. In addition, there are another two obvious shortcomings for the software simulation function: one is low-quality rendering, which can only implement simple graphics rendering; the other is low-speed rendering, which cannot implement real-time rendering. In order to solve these problems, it is necessary to adopt special hardware circuit to realize the 3-D high-definition graphics processing system on mobile devices.The new 3-D real-time graphics processing system for mobile devices should have fast-rendering unit which can realize real-time rendering of 3-D high-definition images and have the characteristics of low power and low bandwidth because of the limitation of battery and small memory bandwidth in mobile devices.In order to meet the urgent need for 3-D high-definition graphics rendering and requirements of 3-D graphics processing system in mobile devices, this thesis takes the design of pixel renderer for mobile devices as the research subject.The thesis bears the following features:Considering the need for 3-D high-definition graphics rendering and the characteristics of mobile devices, this research puts forward the design of a kind of pixel renderer for mobile devices, which has the subsequent characteristics:Firstly, it is programmable design which enables users to implement various pixel rendering algorithm flexibly.Secondly, it applies fixed-point operation that reduces the design complexity and circuit area and thereby lowers the circuit power consumption.Thirdly, the processor adopts four-way parallel SIMD architecture which contains four efficient and parallel multiply-add units.Fourthly, the processor uses pipeline architecture and has data bypass function, so it has a high computational speed, being able to launch one instruction per cycle.Last but not the least, it contains an evaluation unit of special functions with high accuracy, providing hardware accelerated computing of four special functions (reciprocal, radical reciprocal, exponent and logarithm).Up till now, the hardware research into the 3-D graphics processor which is mobile devices oriented has been carried out comprehensively in foreign countries, with some achievements made in related areas. However, the domestic studies on this subject are small in number. Because the key algorithm and hardware design method are core technologies for graphics chip manufacturers and protected by intellectual property rights (IPR), related information for designing 3-D graphics processor is very scarce. In this situation, it has great significance to carry out the research into graphics processor that is mobile device oriented.