Research For Surface Reconstruction Of Reverse Engineering Based On Subdivision Surface

In this paper, the application of subdivision surfaces in the Reverse Engineering (RE), called the reconstruction of subdivision surfaces, is explored.In recent years, subdivision surfaces becomes one of the hot topic in international CAD/CG areas. Besides its local controllability, immutability of affine transformation etc like NURBS, the most outstanding advantage of subdivision surfaces is its arbitrary topology that just is the most difficulty of the development of NURBS. Moreover, subdivision surfaces can guaranteed continuity automatically and avoid concatenating. All above strongpoints make it applied in more and more areas,such as computer cartoon, indurstry design etc. This thesis mostly researches the key technologies of the reconstruction of subdivision surfaces, including:1, Describing the base theory, flow and data-structure of the reconstruction of subdivision surfaces and implementing the Loop subdivision scheme.2, Presenting a new algorithm of mesh simplification based on edge decimation. The error criterion of the new algorithm mostly includes three cost function: the regularity cost function, the cost function of the angle of two meshes with common edge, the cost function of the improved discrete Hausdorff distance. The cost arosed by the edge decimation is calculated by the weighted sum of three cost function. The experiment proved that the speed of operation of the new algorithm is faster than the old algorithm and the quality of meshes is improved. Moreover, the simplification rate is bigger within the same threshold . Another outstanding strongpoint of the new approach is that it can reserve more feature within the same or near simplification rate even if the sharp feature isn't taged.3, Presenting an algorithm of mesh sampling and geometrical optimization based on Laplace smooth arithmetic operators. The new algorithm can avoid the tangent displacement in theory and the speed of operation is faster than the algorithm of tangent projection of Wood especially in operating big and complex mesh model because it avoid the calculation of the normal of every vertex. Secondly, it is proved that the quality of mesh is guaranteed while a better approximation of the original mesh is obtained. In order to improve the simplification of sharp feature, this thesis also implements the simplification algorithm of mesh with sharp feature that can deals with a model with open boundary.4, Presenting a new approach of subdivision-resampling. Compared with all previous algorithms, the projective direction of new algorithm is the normal of the...