#include <Line_2_Line_2_intersection.h>

Collaboration diagram for Line_2_Line_2_pair< R >:

Public Types
enum	Intersection_results { NO, POINT, LINE }

Public Member Functions
	Line_2_Line_2_pair ()

	Line_2_Line_2_pair (Line_2< R > const line1, Line_2< R > const line2)

	~Line_2_Line_2_pair ()

Intersection_results	intersection_type () const

bool	intersection (Point_2< R > &result) const

bool	intersection (Line_2< R > &result) const

Protected Attributes
Line_2< R > const *	_line1

Line_2< R > const *	_line2

bool	_known

Intersection_results	_result

Point_2< R >	_intersection_point

Detailed Description

template<class R>
class Line_2_Line_2_pair< R >

Definition at line 61 of file Line_2_Line_2_intersection.h.

Member Enumeration Documentation

enum Intersection_results

Enumerator
NO
POINT
LINE

Definition at line 63 of file Line_2_Line_2_intersection.h.

63 {NO, POINT, LINE};

Line_2_Line_2_pair::POINT

Definition: Line_2_Line_2_intersection.h:63

Line_2_Line_2_pair::LINE

Definition: Line_2_Line_2_intersection.h:63

Line_2_Line_2_pair::NO

Definition: Line_2_Line_2_intersection.h:63

Constructor & Destructor Documentation

CGAL_END_NAMESPACE CGAL_BEGIN_NAMESPACE Line_2_Line_2_pair ( )

Definition at line 184 of file Line_2_Line_2_intersection.h.

 {
     _line1 = 0;
     _line2 = 0;
     _known = false;
 }

Line_2_Line_2_pair	(	Line_2< R > const *	line1,
		Line_2< R > const *	line2
	)

Definition at line 192 of file Line_2_Line_2_intersection.h.

 {
     _line1 = line1;
     _line2 = line2;
     _known = false;
 }

~Line_2_Line_2_pair ( )

inline

Definition at line 67 of file Line_2_Line_2_intersection.h.

67 {}

Member Function Documentation

bool intersection ( Point_2< R > & result ) const

Definition at line 244 of file Line_2_Line_2_intersection.h.

Referenced by Segment_2_Segment_2_pair< R >::intersection_type().

 {
     if (!_known)
         intersection_type();
     if (_result != POINT)
         return false;
     pt = _intersection_point;
     return true;
 }

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bool intersection ( Line_2< R > & result ) const

Definition at line 256 of file Line_2_Line_2_intersection.h.

 {
     if (!_known)
         intersection_type();
     if (_result != LINE)
         return false;
     l = *_line1;
     return true;
 }

Line_2_Line_2_pair< R >::Intersection_results intersection_type ( ) const

Definition at line 203 of file Line_2_Line_2_intersection.h.

References construct_if_finite(), denom, and is_finite().

Referenced by Segment_2_Segment_2_pair< R >::intersection_type().

 {
     typedef typename R::RT RT;
     if (_known)
         return _result;
     RT nom1, nom2, denom;
     // The non const this pointer is used to cast away const.
     _known = true;
     denom = _line1->a()*_line2->b() - _line2->a()*_line1->b();
     if (denom == RT(0)) {
         if (RT(0) == (_line1->a()*_line2->c() - _line2->a()*_line1->c()) &&
             RT(0) == (_line1->b()*_line2->c() - _line2->b()*_line1->c()))
             _result = LINE;
         else
             _result = NO;
         return _result;
     }
     nom1 = (_line1->b()*_line2->c() - _line2->b()*_line1->c());
     if (!::CGAL::is_finite(nom1)) {
         _result = NO;
         return _result;
     }
     nom2 = (_line2->a()*_line1->c() - _line1->a()*_line2->c());
     if (!::CGAL::is_finite(nom2)) {
         _result = NO;
         return _result;
     }
     R dummyR;
     if (!construct_if_finite(_intersection_point,
                             nom1, nom2, denom, dummyR)){
         _result = NO;
         return _result;
     }
     _result = POINT;
     return _result;
 }