CGAL 5.5.1

CGAL-5.5.1 is a bug-fix release.

See on Github the list of bugs that were solved since CGAL-5.5.

CGAL 5.4.3

CGAL-5.4.3 is a bug-fix release.

See on Github the list of bugs that were solved since CGAL-5.4.2.

CGAL-5.5

The CGAL Open Source Project is pleased to announce the release 5.5 of CGAL, the Computational Geometry Algorithms Library.

Besides fixes and general enhancement to existing packages, the following has changed since CGAL 5.4:

3D Alpha Wrapping (new package)

• This component takes a 3D triangle mesh, soup, or point set as input, and generates a valid (watertight, intersection-free, and combinatorially 2-manifold) surface triangle mesh that contains the input.
  The algorithm proceeds by shrink-wrapping and refining a 3D Delaunay triangulation, starting from a loose bounding box of the input.
  Two user-defined parameters, alpha and offset, offer control over the maximum size of cavities where the shrink-wrapping process can enter, and the tightness of the final surface mesh to the input, respectively. Once combined, these parameters provide a means to trade fidelity
  to the input for complexity of the output.

  See also the announcement page.

2D Straight Skeleton and Polygon Offsetting (breaking change)

• Fix the output of the function CGAL::create_exterior_skeleton_and_offset_polygons_with_holes_2()
  to not take into account the offset of the outer frame.
• Fix the computation of the exterior offset of a polygon with holes that was not computing the offset of the holes

3D Convex Hulls

• Added an overload of the function CGAL::convex_hull_3(), which writes the result in an indexed triangle set.

2D Polygons

• Add vertex, edge, and hole ranges.
• The concept GeneralPolygonWithHoles_2 now requires the nested type Polygon_2 instead of General_polygon_2.

2D Regularized Boolean Set-Operations

• The concept GeneralPolygonSetTraits_2 now requires the nested type Construct_polygon_with_holes_2 instead of Construct_general_polygon_with_holes_2.

Combinatorial Maps

• Removed old code deprecated in CGAL 4.9 and 4.10 (global functions, and information associated with darts).

2D Arrangements

• Fixed the intersect_2, compare_y_at_x_right, and compare_y_at_x_left function objects of the traits class template Arr_geodesic_arc_on_sphere_traits_2 that handles geodesic arcs on sphere and applied a small syntactical fix to the tracing traits.

Tetrahedral Mesh Generation

• Added the function remove_isolated_vertices() as a post-processing step for the tetrahedral mesh generation.

Polygon Mesh Processing

• Added the function CGAL::Polygon_mesh_processing::orient_triangle_soup_with_reference_triangle_soup(), which enables re-orienting the faces of a triangle soup based on the orientation of the nearest face in a reference triangle soup.
• Added the function CGAL::Polygon_mesh_processing::compatible_orientations(), which enables to retrieve the (in)compatibility of orientations of faces from different connected components.
• Added the function CGAL::Polygon_mesh_processing::tangential_relaxation(), which applies an area-based tangential mesh smoothing to the vertices of a surface triangle mesh.
• Added the named parameter visitor to the function triangulate_hole(), which enables to track progress with callbacks.
• Added more functions in the visitor of the corefinement based methods to track progress.

Surface Mesh Simplification

• Introduced four variations of the Garland-Heckbert simplification algorithm based on the probabilistic approach of Trettner and Kobbelt (Fast and Robust QEF Minimization using Probabilistic Quadrics): GarlandHeckbert_plane_policies, GarlandHeckbert_probabilistic_plane_policies, GarlandHeckbert_triangle_policies, and GarlandHeckbert_probabilistic_triangle_policies.
• The class GarlandHeckbert_policies has been deprecated, GarlandHeckbert_plane_policies replaces it.

Point Set Processing

• A new optional named parameter, min_points_per_cell has been added to grid_simplify_point_set(). By adding a minimal number of points in a cell such that a point is retained, one can also filter out low density areas and outliers: in the case of densely sampled point clouds, this yields better results than using grid simplification and then outlier removal, while being very vast. The default value is 1 to keep the previous behavior as default.

dD Spatial Searching

• Added the member function write_graphviz() to the class Kd_tree that writes the tree in a stream in the Graphviz format.

CGAL and the Boost Graph Library (BGL)

• Added the function invert_selection() in the class Face_filtered_graph, which toggles the selected status of a graph: selected faces are deselected, and unselected faces are selected.

CGAL-5.4.2

CGAL-5.4.2 is a bug-fix release.

See on Github the list of bugs that were solved since CGAL-5.4.1.

CGAL-5.4.1

CGAL-5.4.1 is a bug-fix release.

See on Github the list of bugs that were solved since CGAL-5.4.

CGAL-5.3.2

CGAL-5.3.2 is a bug-fix release.

See on Github the list of bugs that were solved since CGAL-5.3.1.

CGAL-5.5-beta1

The CGAL Open Source Project is pleased to announce the release 5.5 Beta 1 of CGAL, the Computational Geometry Algorithms Library.

CGAL version 5.5 Beta 1 is a public testing release. It should provide a solid ground to report bugs that need to be tackled before the release of the final version of CGAL 5.5 in July 2022.

Besides fixes and general enhancement to existing packages, the following has changed since CGAL 5.4:

3D Alpha Wrapping (new package)

• This component takes a 3D triangle mesh, soup, or point set as input, and generates a valid (watertight, intersection-free, and combinatorially 2-manifold) surface triangle mesh that contains the input.
  The algorithm proceeds by shrink-wrapping and refining a 3D Delaunay triangulation, starting from a loose bounding box of the input.
  Two user-defined parameters, alpha and offset, offer control over the maximum size of cavities where the shrink-wrapping process can enter, and the tightness of the final surface mesh to the input, respectively. Once combined, these parameters provide a means to trade fidelity
  to the input for complexity of the output.

  See also the announcement page.

3D Convex Hulls

• Added an overload of the function CGAL::convex_hull_3(), which writes the result in an indexed triangle set.

2D Polygons

• Add vertex, edge, and hole ranges.
• The concept GeneralPolygonWithHoles_2 now requires the nested type Polygon_2 instead of General_polygon_2.

2D Regularized Boolean Set-Operations

• The concept GeneralPolygonSetTraits_2 now requires the nested type Construct_polygon_with_holes_2 instead of Construct_general_polygon_with_holes_2.

Combinatorial Maps

• Removed old code deprecated in CGAL 4.9 and 4.10 (global functions, and information associated with darts).

2D Arrangements

• Fixed the intersect_2, compare_y_at_x_right, and compare_y_at_x_left function objects of the traits class template Arr_geodesic_arc_on_sphere_traits_2 that handles geodesic arcs on sphere and applied a small syntactical fix to the tracing traits.

Tetrahedral Mesh Generation

• Added the function remove_isolated_vertices() as a post-processing step for the tetrahedral mesh generation.

Polygon Mesh Processing

• Added the function CGAL::Polygon_mesh_processing::orient_triangle_soup_with_reference_triangle_soup(), which enables re-orienting the faces of a triangle soup based on the orientation of the nearest face in a reference triangle soup.
• Added the function CGAL::Polygon_mesh_processing::compatible_orientations(), which enables to retrieve the (in)compatibility of orientations of faces from different connected components.
• Added the function CGAL::Polygon_mesh_processing::tangential_relaxation(), which applies an area-based tangential mesh smoothing to the vertices of a surface triangle mesh.
• Added the named parameter visitor to the function triangulate_hole(), which enables to track progress with callbacks.
• Added more functions in the visitor of the corefinement based methods to track progress.

Surface Mesh Simplification

• Introduced four variations of the Garland-Heckbert simplification algorithm based on the probabilistic approach of Trettner and Kobbelt (Fast and Robust QEF Minimization using Probabilistic Quadrics): GarlandHeckbert_plane_policies, GarlandHeckbert_probabilistic_plane_policies, GarlandHeckbert_triangle_policies, and GarlandHeckbert_probabilistic_triangle_policies.
• The class GarlandHeckbert_policies has been deprecated, GarlandHeckbert_plane_policies replaces it.

Point Set Processing

• A new optional named parameter, min_points_per_cell has been added to grid_simplify_point_set(). By adding a minimal number of points in a cell such that a point is retained, one can also filter out low density areas and outliers: in the case of densely sampled point clouds, this yields better results than using grid simplification and then outlier removal, while being very vast. The default value is 1 to keep the previous behavior as default.

dD Spatial Searching

• Added the member function write_graphviz() to the class Kd_tree that writes the tree in a stream in the Graphviz format.

CGAL and the Boost Graph Library (BGL)

• Added the function invert_selection() in the class Face_filtered_graph, which toggles the selected status of a graph: selected faces are deselected, and unselected faces are selected.

CGAL-5.4

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. See changes in 2D and 3D Linear Geometry Kernel for 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.

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.

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.

2D and 3D Linear Geometry Kernel

• Most operations on CGAL::Exact_predicates_exact_constructions_kernel objects are now thread-safe if CGAL::Exact_rational is mpq_class (from GMPXX), boost::multiprecision::mpq_rational or CGAL::Quotient<CGAL::MP_Float>. The objects are not atomic though, so the usual restrictions on avoiding race conditions apply. For users who do not use threads, this can be disabled with CGAL_HAS_NO_THREADS.

• Added documentation for the class Projection_traits_3, which enables the use of 2D algorithms on the projections of 3D data onto an arbitrary plane.

• Added construct_centroid_2_object() and compute_determinant_2_object() in Projection_traits_xy_3, Projection_traits_xz_3, and Projection_traits_yz_3 classes.

• Added the functor NonZeroCoordinateIndex_3 to the concept Kernel with int operator()(Vector_3) which returns the index of any coordinate of the vector different from zero, or -1.

dD Kernel

• Most operations on Epeck_d objects are now thread-safe, see 2D and 3D Linear Geometry Kernel for details.

2D Arrangements

• Breaking Change: The traits function objects Compare_x_at_limit_2 and Compare_x_near_limit_2 are renamed to Compare_x_on_boundary_2 and Compare_x_near_boundary_2, respectively.

• A new hierarchy of traits concepts has been introduced. It captures all the valid combinations of boundary conditions for the 4 boundary sides of the parameter space. The 4 boundaries are Bottom, Top, Left, and Right. Each boundary side can be either contracted, identified, close, open, or oblivious. Not all possible combinations are valid. If one side is identified then the other must be as well. Two adjacent sides cannot be contracted.

• A new geometric traits, Arr_geodesic_arc_on_sphere_traits_2 has been introduced. It handles arcs of great circles embedded on the unit sphere.

2D Regularized Boolean Set-Operations

• Added an extra parameter (UsePolylines) to all free functions ( [`complement()...

CGAL-5.4-beta1

The CGAL Open Source Project is pleased to announce the release 5.4 Beta 1 of CGAL, the Computational Geometry Algorithms Library.

CGAL version 5.4 Beta 1 is a public testing release. It should provide a solid ground to report bugs that need to be tackled before the release of the final version of CGAL 5.4 in January 2022.

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. See changes in 2D and 3D Linear Geometry Kernel for more details.

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.

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.

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.

2D and 3D Linear Geometry Kernel

• Most operations on CGAL::Exact_predicates_exact_constructions_kernel objects are now thread-safe if CGAL::Exact_rational is mpq_class (from GMPXX), boost::multiprecision::mpq_rational or CGAL::Quotient<CGAL::MP_Float>. The objects are not atomic though, so the usual restrictions on avoiding race conditions apply. For users who do not use threads, this can be disabled with CGAL_HAS_NO_THREADS.

• Added documentation for the class Projection_traits_3, which enables the use of 2D algorithms on the projections of 3D data onto an arbitrary plane.

• Added construct_centroid_2_object() and compute_determinant_2_object() in Projection_traits_xy_3, Projection_traits_xz_3, and Projection_traits_yz_3 classes.

• Added the functor NonZeroCoordinateIndex_3 to the concept Kernel with int operator()(Vector_3) which returns the index of any coordinate of the vector different from zero, or -1.

dD Kernel

• Most operations on Epeck_d objects are now thread-safe, see 2D and 3D Linear Geometry Kernel for details.

2D Arrangements

• Breaking Change: The traits function objects Compare_x_at_limit_2 and Compare_x_near_limit_2 are renamed to Compare_x_on_boundary_2 and Compare_x_near_boundary_2, respectively.

• A new hierarchy of traits concepts has been introduced. It captures all the valid combinations of boundary conditions for the 4 boundary sides of the parameter space. The 4 boundaries are Bottom, Top, Left, and Right. Each boundary side can be either contracted, identified, close, open, or oblivious. Not all possible combinations are valid. If one side is identified then the other must be as well. Two adjacent sides cannot be contracted.

• A new geometric traits, Arr_geodesic_arc_on_sphere_traits_2 has been introduced. It handles arcs of great circles embedded on the unit sphere.

2D Regularized Boolean Set-Operations

• Added an extra parameter (UsePolylines) to all free functions ( [`comp...

CGAL-5.3.1

CGAL-5.3.1 is a bug-fix release.

See on Github the list of bugs that were solved since CGAL-5.3.