The contour generator is an important visibility feature of a smooth object seen under parallel projection. It is the curve on the surface which seperates front-facing regions from back-facing regions. The apparent contour is the projection of the contour generator onto a plane perpendicular to the view direction. Both curves play an important role in computer graphics. Our goal is to obtain fast and robust algorithms that compute the contour generator with a guarantee of topological correctness. To this end, we first study the singularities of the contour generator and the apparent contour, for generic views, and for generic time-dependent projections, e.g. when the surface is rotated or deformed. The singularities indicate when components of the contour generator merge or split as time evolves. We present an algorithm to compute an initial contour generator, using a dynamic step size. An interval test guarantees the topological correctness. This initial contour generator can then be maintained under a time-dependent projection by examining its singularities.


    Access

    Download


    Export, share and cite



    Title :

    Contour Generators of Evolving Implicit Surfaces


    Contributors:

    Publication date :

    2003-01-01


    Remarks:

    Plantinga , S & Vegter , G 2003 , Contour Generators of Evolving Implicit Surfaces . in EPRINTS-BOOK-TITLE . University of Groningen, Johann Bernoulli Institute for Mathematics and Computer Science .


    Type of media :

    Article/Chapter (Book)


    Type of material :

    Electronic Resource


    Language :

    English



    Classification :

    DDC:    629



    Computing Contour Generators of Evolving Implicit Surfaces

    Plantinga, Simon / Vegter, Gert | BASE | 2006

    Free access

    Implicit surfaces make for better silhouettes

    Ilic, S. / Salzmann, M. / Fua, P. | IEEE | 2005


    Variational Problems and PDE's on Implicit Surfaces

    Bertalmio, M. / Sapiro, G. / Cheng, L.-T. et al. | British Library Conference Proceedings | 2001


    Variational problems and PDEs on implicit surfaces

    Bertalmio, M. / Sapiro, G. / Li-Tien Cheng, et al. | IEEE | 2001


    Quadratic Transformation for Planar Mapping of Implicit Surfaces

    Molnár, J. z. | British Library Online Contents | 2014