Large-scale Herbaceous Vegetation Rendering Graphics Engine Research And Implementation

With the development of computer hardware, computer graphic softwares applied in game, video and cartoon industries become more and more complicate. Many problems were appeared such as increasing of architecture complexity, long time coding cycles and difficulties of development come with a real and complex scene rendering. Graphic engines take a core role in today's large-scale CG software both for optimizing and simplifying. This thesis presents the design and implementation of a graphic engine called Gingko and it also focuses on researches about real time rendering of large-scale herbaceous plants and gives an implementation based on the graphic engine.The thesis is organized with three parts.First, we give a short introduction about the project's background including domestic and overseas research states and subsistent results. Then we combine design pattern theories and core components'implementation together to give a comprehensive description of Gingko's architecture. Gingko is an object-oriented, plug-in based and easy to extend general framework for large-scale CG software development. Contrast to other open source game engines like OGRE and OGS, Gingko provide important functions such as scene management, rendering management, message mechanism and so on. Further more, Gingko provide a facile method for a simple function extension by users other than write complex plug-in. We also take the phenomena that more and more CG software use GPU programming into account when design Gingko's architecture and the thesis will emphasis this point in render system component's introduction.Secondly, we discuss about real time rendering of large-scale herbaceous plants based on Gingko. As a most important part of large-scale out-door real time rendering, how to look after both sides of effect and efficient is the key point all the time. After long time research, there exist a lot of amazing algorithms for grass'modeling, lighting, shadowing and anmimation. In this thesis, we introuduce harvests in herbaceous plants rendering research during last twenty years, then we make a comparation and summarization about them. Further more, this thesis discuss an innovation method when use geometry based algorithms for finest grass molding. We employ a 2D sketch graph and deform algorithm to make grass model. The sketch graph comes from a grass entity scanned by a scanner device. Unlike other common methods, the model created by sketch graph and deform is more suitable for grass rendering and animation. We impleted a system based on Gingko for out-door plant rendering and the thesis will discuss it in chapter five.At last part of this thesis, we make an outlook of the computer graphic's future and the development of large-scale out-door scene rendering in real time. Furthermore, we specify some important and meaningful research aspects in computer graphic.