The Design And Implementation Of3D Graphic Processing Unit For Mobile Device

As the improvement of computer graphic Algorithm and hardware on PC platform,high quality3D graphic is deeply rooted. Realistic display is adopted more widely ineveryday applications, like mobile phone, tablet PC, automotive GPS, medical andindustrial handset equipment. Though3D rendering is highly developed on PC platform,due to critical limitation of power consumption and bandwidth, the high performance, highpower, high bandwidth PC graphic system could not get migrated to mobile device easily.Meanwhile, traditional solution for embedded graphic system which uses software to draw3D graphic is too slow to satisfy the requirement of applications. Under this situation, thespecialized graphic hardware and API for embedded system has been finally recognitionThe paper focus on the characteristics of mobile device, after analyzing the basicalgorithm of3D graphic, build a32bit programmable vertex processor, with dedicated datacache and instruction memory, supporting4way SIMD and data forward, mainly used incalculating geometry transform and vertex lighting, and controlling the following processon raster, texture and pixel. The raster module uses Tile based rendering which is mostsuitable for mobile device. The corresponding on-chip Z-buffer and frame buffer couldsignificantly reduce access to off-chip memory which leads to power and bandwidth saving.After finishing algorithm verification under software environment and RTL simulation,a FPGA based platform with SOPC method is build including the whole graphic system,Nios embedded CPU, embedded logic analyzer and other peripherals. The FPGA systemhas run a demo ASM program which is written by custom instruction set, working at125MHz, rendering nearly10thousands triangles with bilinear texture filtering in20-25ms.Based on the verification of FPGA system and analyze of the result imagine fromhardware and algorithm perspective, the system in this paper is proved to satisfy the basicrequirement of embedded graphics and could be referenced in the further development.