【摘要】 提出一种基于面形位码的模型检索方法.计算模型中任意面f的形位码分为2步.首先根据实体的B-rep结构生成属性邻接图并将图转化为以面f为中心的层状结构;然后根据图的层状结构对每一层进行递归的编码,形成一种分阶的形位码.根据模型中所有面的形位码构造一个表达模型整体形状的描述矩阵,利用该矩阵可以有效地评估模型之间不同精度要求下的相似度,从而实现模型检索.实验结果表明,该方法不但具有较高的搜索效率,并且能根据不同精度的要求搜索到合适的相似模型.更多还原

【Abstract】 A model-retrieval approach based on shape-location codes of faces is proposed.The code for a face f is generated in two steps.First,an attributed relational graph(ARG)is constructed from a B-rep model and the ARG is transformed to a layered configuration whose center is the face f.Second,face f’s shape-location code is recursively evaluated in the order of the layers,taking into account shapes of faces in each layer and their distances to the center of the configuration.Using all the face shape-location codes of a solid model,a code matrix,called shape description matrix,is constructed to represent the shape of the model.By means of shape description matrices,the representation precisions of model similarities are adjustable and model retrieval can be carried out.The experimental results show that this approach not only has high efficiency but also can retrieve models that have different levels of similarities.更多还原