CGAL users discussion list

["Laurent Rineau (CGAL/GeometryFactory)" <>]

The CGAL Open Source Project is pleased to announce the release 5.4
of CGAL, the Computational Geometry Algorithms Library.


Besides fixes and general enhancement to existing packages, the following
has changed since CGAL 5.3:


General changes

-   Added the cmake target CGAL::CGAL_Basic_viewer to ease the
    compilation of programs using the basic viewer-based function
    CGAL::draw(). This target will define the macro and link with
    CGAL_Qt5 target when linked with it.

-   The kernel providing exact constructions and exact predicates
    (CGAL::Exact_predicates_exact_constructions_kernel) is now
    thread-safe.
    more details.

-   The class Geomview_stream and all the dependent features have
    been removed from CGAL. Those features were actually no longer
    supported since CGAL-5.3 but it was not properly announced.


Shape Regularization (new package)

-   This package enables to regularize a set of segments and open or
    closed contours in 2D and a set of planes in 3D such that all input
    objects are rotated and aligned with respect to the user-specified
    conditions. In addition, it provides a global regularization
    framework that can be adjusted for the user needs and any type of
    geometric objects.

      https://www.cgal.org/2021/11/16/shape-regularization/

      https://doc.cgal.org/5.4/Manual/packages.html#PkgShapeRegularization


Weights (new package)

-   This package provides a simple and unified interface to different
    types of weights. In particular, it groups all weights into three
    category: analytic weights including all basic weights which can be
    computed analytically for a query point with respect to its local
    neighbors in 2D and 3D; barycentric weights, including all weights
    which can be computed for a query point with respect to the vertices
    of a planar polygon; and weighting regions, including all weights
    which are used to balance other weights.

      https://doc.cgal.org/5.4/Manual/packages.html#PkgWeights


2D Generalized Barycentric Coordinates (major changes)

-   Breaking change: The headers Segment_coordinates_2.h and
    Triangle_coordinates_2.h are renamed to segment_coordinates_2.h and
    triangle_coordinates_2.h.
-   The classes Segment_coordinates_2 and Triangle_coordinates_2 are
    deprecated. The free functions compute_segment_coordinates_2() and
    compute_triangle_coordinates_2() are deprecated as well. Instead,
    the free functions segment_coordinates_2() and
    triangle_coordinates_2() should be used.
-   The enums Query_point_location and Type_of_algorithm are deprecated.
    Instead, the enum Computation_policy_2 should be used.
-   The classes Wachspress_2, Discrete_harmonic_2, Mean_value_2, and
    Generalized_barycentric_coordinates_2 are deprecated. As
    consequence, the concept BarycentricCoordinates_2 is deprecated as
    well. Instead, the classes Wachspress_coordinates_2,
    Discrete_harmonic_coordinates_2, and Mean_value_coordinates_2 should
    be used.
-   Added the class Harmonic_coordinates_2 to compute approximate
    harmonic coordinates in 2D. These coordinates satisfy all properties
    of barycentric coordinates inside any simple polygon.
-   Added a new concept DiscretizedDomain_2 and a model of this concept
    called Delaunay_domain_2, which is based on the Mesh 2 package. A
    model of this concept is required to use Harmonic_coordinates_2.
-   Added free functions to compute Wachspress, discrete harmonic, and
    mean value coordinates.
-   All free functions and classes are now using ranges and property
    maps.

      https://doc.cgal.org/5.4/Manual/packages.html#PkgBarycentricCoordinates2


See https://www.cgal.org/2022/01/31/cgal54/ for a
complete list of changes.


The CGAL project is a collaborative effort to develop a robust,
easy-to-use, and efficient C++ software library of geometric data
structures and algorithms, like
- triangulations (2D constrained triangulations, Delaunay triangulations
  and periodic triangulations in 2D and 3D),
- Voronoi diagrams (for 2D and 3D points, 2D additively weighted
  Voronoi diagrams, and segment Voronoi diagrams),
- Boolean operations on polygons and polyhedra,
- regularized Boolean operations on polygons with curved arcs
- arrangements of curves,
- mesh generation (2D, 3D and surface mesh generation,
  surface mesh subdivision and parametrization),
- alpha shapes (in 2D and 3D),
- convex hull algorithms (in 2D, 3D and dD),
- operations on polygons (straight skeleton and offset polygon),
- search structures (kd trees for nearest neighbor search, and
  range and segment trees),
- interpolation (natural neighbor interpolation and placement of
  streamlines),
- optimization algorithms (smallest enclosing sphere of points or
  spheres, smallest enclosing ellipsoid of points, principal
  component analysis).




Some modules are distributed under the terms of the LGPL Open Source
license (GNU Lesser General Public License v3 or later versions).
Most modules are distributed under the terms of the GPL Open Source
license (GNU General Public License v3 or later versions).
If your intended usage does not meet the criteria of the
aforementioned licenses, a commercial license can be purchased from
GeometryFactory (http://www.geometryfactory.com/).


For further information and for downloading the library and its
documentation, please visit the CGAL web site: https://www.cgal.org/


-- 
Laurent Rineau, PhD
R&D Engineer at GeometryFactory           http://www.geometryfactory.com/
Release Manager of the CGAL Project       http://www.cgal.org/