CGAL-ipelets
Computational Geometry
            Algorithms Library

CGAL-3.5 now contains the CGAL ipelets as demos. This separate distribution is therefore obsolete. We keep it available for a while for users of CGAL versions anterior to 3.5. Please check the CGAL manual and the ipelets chapter. Also note that these ipelets do not work with Ipe version 7, they require Ipe 6.



The CGAL-ipelets project aims to make available in IPE main functionalities of 2D algorithms of CGAL and more generally key features used by the computational geometry community.

Functionalities available are the following :

  • Alpha-shape
    • Draw the boundary of the alpha-shape and its faces for the k-th critical spectral value.
  • Arrangement
    • Given a set of circles, segments, polygons and circles arcs, compute the segmentation induced by intersection points and points of discontinuity for x-monotonicity.
    • Given a set of general segments, such that each endpoint is shared exactly twice, change this union to a closed path ---i.e. fillable.
    • Given several closed paths, join them ---useful to fill a face with several holes.
  • Diagrams
    • Draw power ---using circles and points, Voronoi ---using points, segments, and Apollonius ---using circles and points, diagrams.
  • Hilbert Curve
    • Given a set of points, draw a Hilbert curve sorting this points.
  • Hulls package
    • Draw the minimal convex hull of a set of segments, circles and points.
    • Draw the result of the crust algorithm for a set of points.
  • K-th Delaunay
    • Draw k-th Voronoi diagram or Delaunay triangulation of a set of points.
  • K-th regular
    • Draw the k-th Power diagram or Regular triangulation of a set of weighted points ---using circles.
  • Mesh_2
    • Mesh a close domain using algorithm Mesh_2: seeds are specified by circles.
  • Minkowski Sum
    • Draw the Minkowski sum of two simple polygons. Origin is placed at the min point of the bounding box of the selected objects.
    • Draw the offsets of a simple polygon defined by a set of circles.
  • Polygon partition
    • Draw the convex partition of a polygon using several algorithms.
  • Random Generators
    • Generate random set of points, circles, segments.
  • Triangulation
    • Draw regular ---using circles and points, constrained ---using points and segments, Delaunay, Conforming Delaunay. Conforming Gabriel triangulations

Project News

6 Oct 2009 CGAL-3.5 now contains the CGAL ipelets as demos. This separate distribution is therefore obsolete. Please check the CGAL manual and the ipelets chapter.
13 Aug 2007 CGAL-ipelets-0.9 is now available.