Shape simplification of free-form surface objects for multi-scale representation

High-speed display of a 3-D object in virtual reality environments is one of the currently important subjects. Shape simplification is considered an efficient method. This paper presents a new approach to the shape simplification of arbitrary shape 3-D objects for generating multiresolution models. The algorithm relies upon the modeling of an arbitrary shape object with scattered range data delivered from multiple view range images. The relationship among shape simplification, resolution and visual distance are given. The idea of the algorithm is to construct an arbitrary shape of a 3-D object using cube-based segmentation and therefore to adjust the cube sizes adaptively using octree hierarchical structure for multiresolution description. The first level model is constructed from scattered range data with the first level cube size. Multiresolution models are then generated by re-sampling the polygonal vertices of each former level patches. The results show that the algorithm can simply and quickly generate multiresolution models from multiple view range images and the high compression ratio can be obtained with little noticeable difference during the visualization