CGAL 5.5.2 - 2D Envelopes
EnvelopeDiagramEdge Concept Reference

Definition

An edge record in an envelope diagram, which represents a continuous portion of the \( x\)-axis. It is associated with a (possibly empty) set of curves that induce the envelope over this portion of the \( x\)-axis. Note that all curves in this set overlap over the interval represented by the edge.

See also
EnvelopeDiagram_1
EnvelopeDiagramVertex

Types

typedef unspecified_type Size
 the size type (convertible to size_t).
 
typedef unspecified_type Vertex
 the corresponding diagram-vertex type.
 
typedef unspecified_type X_monotone_curve_2
 the \( x\)-monotone curve type.
 

Creation

 EnvelopeDiagramEdge ()
 default constructor.
 
 EnvelopeDiagramEdge (const EnvelopeDiagramEdge &other)
 copy constructor.
 

Access Functions

Size number_of_curves () const
 returns the number of \( x\)-monotone curves associated with e.
 
bool is_empty () const
 returns whether e represents an empty interval - namely, whether the set of \( x\)-monotone curves associated with it is empty.
 
const X_monotone_curve_2curve () const
 returns a representative \( x\)-monotone curve associated with e. More...
 
Curve_const_iterator curves_begin () const
 returns an iterator for the first \( x\)-monotone curve associated with e.
 
Curve_const_iterator curves_end () const
 returns a past-the-end iterator for the \( x\)-monotone curves associated with e.
 
Vertex_const_handle left () const
 returns the vertex lying to e's left. More...
 
Vertex_const_handle right () const
 returns the vertex lying to e's right. More...
 

Modifiers

void clear_curves ()
 clears the set of curves associated with e.
 
void add_curve (const X_monotone_curve_2 &cv)
 adds the \( x\)-monotone curve cv to the set of curves associated with e.
 
void add_curves (Curve_const_iterator begin, Curve_const_iterator end)
 adds the given range of \( x\)-monotone curves to the set of curves associated with e.
 
void set_left (Vertex_const_handle v)
 sets the vertex lying to the left of e to be v.
 
void set_right (Vertex_const_handle v)
 sets the vertex lying to the right of e to be v.
 

Member Function Documentation

◆ curve()

const X_monotone_curve_2& EnvelopeDiagramEdge::curve ( ) const

returns a representative \( x\)-monotone curve associated with e.

Precondition
e does not represent an empty interval.

◆ left()

Vertex_const_handle EnvelopeDiagramEdge::left ( ) const

returns the vertex lying to e's left.

Precondition
e is not the leftmost edge in the diagram.

◆ right()

Vertex_const_handle EnvelopeDiagramEdge::right ( ) const

returns the vertex lying to e's right.

Precondition
e is not the rightmost edge in the diagram.