Research On Approaches Of Surface Texture Rendering And Their Implementation

Surface texturing technique is one of the most popular techniques of realistic graph rendering. It can efficiently simulate the details of 3D surfaces without increasing the complexity of the geometric model, and has been widely applied in many fields such as 3D game, computer animation, virtual reality, CAD and so forth. In this thesis, we deeply studied some texture techniques, such as texture mapping, solid texture rendering and texture synthesis from samples etc. The main contributions and innovations are as follows:1. The method of two-step texture mapping is discussed and an improvement is made on the S mapping of it, which can effectively reduce the distortion of mapped texture. By using the weighted interpolation, the junctures of mapped texture patches can be removed and the visual quality of produced texture can be amended. Then a new algorithm of two-step texture mapping for annular objects is presented using a torus as the intermediate surface.2. The techniques of sphere texture mapping is studied and an improved algorithm of hemisphere texture mapping is proposed, which can obviously decrease the distortion of mapped texture by obeying the non-distortion criterions of sphere texture mapping and introducing a constraint of equal area-ratio. Moreover, we extended the algorithm to solve the problem of texture mapping for partial area of a sphere.3. A novel algorithm of rendering solid texture from samples is proposed, which can render solid texture directly onto an object surface by establishing geometrical mappings among the specimen space, solid texture space and object surface. The solid texture produced by the method can represents texture details on the samples and is continuous on the conterminous surfaces of an object. Therefore, the reality and diversity of texturing is evidently raised.4. A novel algorithm is proposed to speed up the process of surface texture synthesis, which uses local area texture mapping. A mesh-optimizing algorithm is presented which is used in the mesh preprocess of surface texture synthesis. Moreover, a texture triangular assembly algorithm for setting texture atlas is presented which is based on triangular height sorting to raise the space usage rate of the atlas.5. An experiment system is designed and implemented, which can adopt many texture rendering methods. In the system, two novel algorithms are proposed for texture preprocessing: one is the local histogram equalization algorithm with image brightness preservation, which is used to enhance the contrast of the texture; another is the Catmull-Rom spline method with...