Patent · US Expired

Methods, apparatus and computer program products for automatically generating nurbs models of triangulated surfaces using homeomorphisms

US6996505B1 · kind B1 · utility

33Cited by
57References
36Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 29, 2000
Grant dateFeb 7, 2006
Priority date
Expiry dateJun 29, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T17/20
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Embodiments automatically generate an accurate network of watertight NURBS patches from polygonal models of objects while automatically detecting and preserving character lines thereon. These embodiments generate from an initial triangulation of the surface, a hierarchy of progressively coarser triangulations of the surface by performing a sequence of edge contractions using a greedy algorithm that selects edge contractions by their numerical properties. Operations are also performed to connect the triangulations in the hierarchy using homeomorphisms that preserve the topology of the initial triangulation in the coarsest triangulation. A desired quadrangulation of the surface can then be generated by homeomorphically mapping edges of a coarsest triangulation in the hierarchy back to the initial triangulation. This quadrangulation is topologically consistent with the initial triangulation and is defined by a plurality of quadrangular patches. These quadrangular patches are linked together by a (U, V) mesh that is guaranteed to be continuous at patch boundaries. A grid is then preferably fit to each of the quadrangles in the resulting quadrangulation by decomposing each of the quadra…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.