关键词: 参数分布, 欠约束区域, 双向蒙皮, 插值四边/三角细分

Abstract:

According to the information of original surfaces, original meshes and deformed meshes, a method for reconstructing B-spline surfaces with consistent parametric distribution was presented. In trimmed regions, initial fitting surfaces were constructed by some operations on original surfaces such as translation, extension, segment and reparametrization, etc. In untrimmed regions, bidirectional skinning method was adopted for the production of initial surfaces after inserting section lines across the highly curved boundaries and revising their parameterization. Then a loop of reparameterizing the nodes and refitting the surfaces proceeded until some ending rules were satisfied. During the process of iteration, a more precise method was presented for determining under-constrained regions by calculating extreme points of basis functions; fairness of the fitting surfaces was improved evidently by splitting coarse meshes to provide enough constraints with interpolatory quad/triangle subdivision scheme. Fitting precision is improved for trimmed surfaces by dint of boundaries and internal nodes interpolation constraints together with shape preservation constraints of under-constrained regions. Test results indicate effectivity of the proposed method.

Key words: parametric distribution, under-constrained region, bidirectional skinning;interpolatory quad/triangle subdivision