The Research And Implement Of Large Scale Scene Rendering Techniques In 3D Game Engines

With the constant development, current game engine has become a complicated system consists of many subsystems, and the rendering system is the most important part of which As a result, the technical level of a rendering system implies which of the game itself.The large scale outdoor scene rendering is one of the difficult problems of 3D game engine, the research and implies of which a core task in game development is.This dissertation, at first, will analyze the character of 3D engine then, introduce some technology of the large scale scene rendering, which include the terrain rendering and realization of drawing.The dissertation utilizes an amelioratied two-branch based LOD algorithm calculating method to solve the problem of triangle quantities in large scale terrain rendering. In this paper, the view-dependent and terrain's roughness is used to determine the terrain detail. The terrain mesh is refined before render, only the vertices are needed will be rendered. So the mesh grid is irregular.The far from the viewer, the less detail. The terrain node subdivided until the desire detail. The subdividing depends on the node level, the terrain's roughness and the distance between the viewer and the node. The roughness factor is pre-calculated to improve speed.In order to design the realized scene, several light-ware calculating model, painting model and texture reflecting model, that well simulate the sky, earth's surface, water, movement blur and other effects, which must been achieved in the game scene.At last, a terrain rendering system is designed and implemented in this thesis, which also give some future research directions.