CGAL 5.1.2 - 2D Straight Skeleton and Polygon Offsetting
StraightSkeletonBuilder_2_Visitor Concept Reference

Definition

The concept StraightSkeletonBuilder_2_Visitor describes the requirements of the visitor class required by the algorithm class Straight_skeleton_builder_2<Gt,Ss,Visitor> in its third template parameter.

Has Models:
CGAL::Dummy_straight_skeleton_builder_2_visitor
See also
CGAL::Straight_skeleton_builder_2<Gt,Ss>

Types

typedef unspecified_type Halfedge_const_handle
 A constant handle to a straight skeleton halfedge.
 
typedef unspecified_type Vertex_const_handle
 A constant handle to a straight skeleton vertex.
 

Operations

void on_contour_edge_entered (Halfedge_const_handle const &) const
 Called for each contour halfedge added to the skeleton).
 
void on_initialization_started (std::size_t number_of_vertices) const
 Called before the initialization stage (when initial events are discovered) is started.
 
void on_contour_vertex_processed (Vertex_const_handle const &v, bool is_reflex, bool is_degenerate) const
 Called after the events for contour vertex v have been discovered. More...
 
void on_edge_event_created (Vertex_const_handle const &node0, Vertex_const_handle const &node1) const
 Called after an edge event for nodes node0 and node1 has been discovered and put on the queue for later processing.
 
void on_split_event_created (Vertex_const_handle const &node) const
 Called after a slipt event for node node has been discovered and put on the queue for later processing.
 
void on_pseudo_split_event_created (Vertex_const_handle const &node0, Vertex_const_handle const &node1) const
 Called after a pseudo slipt event for nodes node0 and node1 has been discovered and put on the queue for later processing.
 
void on_initialization_finished () const
 Called after all initial events have been discovered.
 
void on_propagation_started () const
 Called before the propagation stage (when events are poped off the queue and processed) is started.
 
void on_anihiliation_event_processed (Vertex_const_handle const &node0, Vertex_const_handle const &node1) const
 Called after an anhiliation event for nodes node0 and node1 has been processed. More...
 
void on_edge_event_processed (Vertex_const_handle const &seed0, Vertex_const_handle const &seed1, Vertex_const_handle const &newnode) const
 Called after an edge for nodes seed0 and seed1 has been processed. More...
 
void on_split_event_processed (Vertex_const_handle const &seed, Vertex_const_handle const &newnode0, Vertex_const_handle const &newnode1) const
 Called after a split event for node seed has been processed. More...
 
void on_pseudo_split_event_processed (Vertex_const_handle const &seed0, Vertex_const_handle const &seed1, Vertex_const_handle const &newnode0, Vertex_const_handle const &newnode1) const
 Called after a pseudo split event for nodes seed0 and seed1 has been processed. More...
 
void on_vertex_processed (Vertex_const_handle const &v) const
 Called after vertex v has been marked as already processed.
 
void on_propagation_finished () const
 Called after all events have been processed.
 
void on_cleanup_started () const
 Called when the skeleton clean up (when multiple nodes are merged) is started.
 
void on_cleanup_finished () const
 Called when clean up finished.
 
void on_algorithm_finished (bool finished_ok) const
 Called when the algorithm terminated. More...
 
void on_error (char const *msg) const
 Called whenever an error was detected. More...
 

Member Function Documentation

◆ on_algorithm_finished()

void StraightSkeletonBuilder_2_Visitor::on_algorithm_finished ( bool  finished_ok) const

Called when the algorithm terminated.

finished_ok is false if it terminated before completion or the resulting skeleton was found to be invalid.

◆ on_anihiliation_event_processed()

void StraightSkeletonBuilder_2_Visitor::on_anihiliation_event_processed ( Vertex_const_handle const &  node0,
Vertex_const_handle const &  node1 
) const

Called after an anhiliation event for nodes node0 and node1 has been processed.

A new skeleton edge between these nodes has been added.

◆ on_contour_vertex_processed()

void StraightSkeletonBuilder_2_Visitor::on_contour_vertex_processed ( Vertex_const_handle const &  v,
bool  is_reflex,
bool  is_degenerate 
) const

Called after the events for contour vertex v have been discovered.

is_reflex is true if this vertex has an internal angle \( > \pi\), or is_degenerate is true if the internal angle is \( = \pi\).

◆ on_edge_event_processed()

void StraightSkeletonBuilder_2_Visitor::on_edge_event_processed ( Vertex_const_handle const &  seed0,
Vertex_const_handle const &  seed1,
Vertex_const_handle const &  newnode 
) const

Called after an edge for nodes seed0 and seed1 has been processed.

Skeleton vertex newnode and edges from node0 to newnode and node1 to newnode has been added.

◆ on_error()

void StraightSkeletonBuilder_2_Visitor::on_error ( char const *  msg) const

Called whenever an error was detected.

msg is whatever error message accompanies the error. This pointer can be null.

◆ on_pseudo_split_event_processed()

void StraightSkeletonBuilder_2_Visitor::on_pseudo_split_event_processed ( Vertex_const_handle const &  seed0,
Vertex_const_handle const &  seed1,
Vertex_const_handle const &  newnode0,
Vertex_const_handle const &  newnode1 
) const

Called after a pseudo split event for nodes seed0 and seed1 has been processed.

Skeleton vertices newnode0 and newnode1 have been added. Skeleton edges from seed0 to newnode0 and seed1 to newnode1 has been added.

◆ on_split_event_processed()

void StraightSkeletonBuilder_2_Visitor::on_split_event_processed ( Vertex_const_handle const &  seed,
Vertex_const_handle const &  newnode0,
Vertex_const_handle const &  newnode1 
) const

Called after a split event for node seed has been processed.

Skeleton vertices newnode0 and newnode1 have been added. An skeleton edge from seed to newnode0 has been added. In the final skeleton, newnode1 is removed and only newnode0 remains.