p2t Namespace Reference

Sweep-line, Constrained Delauney Triangulation (CDT) See: Domiter, V. More...

Classes
struct	Point
struct	Edge
class	Triangle
struct	Node
class	AdvancingFront
class	CDT
class	Sweep
class	SweepContext

Enumerations
enum	Orientation { CW , CCW , COLLINEAR }

Functions
std::ostream &	operator<< (std::ostream &out, const Point &point)
bool	IsDelaunay (const std::vector< p2t::Triangle * > &)
	Is this set a valid delaunay triangulation?
bool	cmp (const Point *a, const Point *b)
Point	operator+ (const Point &a, const Point &b)
	Add two points_ component-wise.
Point	operator- (const Point &a, const Point &b)
	Subtract two points_ component-wise.
Point	operator* (double s, const Point &a)
	Multiply point by scalar.
bool	operator== (const Point &a, const Point &b)
bool	operator!= (const Point &a, const Point &b)
double	Dot (const Point &a, const Point &b)
	Peform the dot product on two vectors.
double	Cross (const Point &a, const Point &b)
	Perform the cross product on two vectors. In 2D this produces a scalar.
Point	Cross (const Point &a, double s)
	Perform the cross product on a point and a scalar.
Point	Cross (double s, const Point &a)
	Perform the cross product on a scalar and a point.
Orientation	Orient2d (const Point &pa, const Point &pb, const Point &pc)
	Forumla to calculate signed area Positive if CCW Negative if CW 0 if collinear .
bool	InScanArea (const Point &pa, const Point &pb, const Point &pc, const Point &pd)

Variables
const double	PI_3div4 = 3 * M_PI / 4
const double	PI_div2 = 1.57079632679489661923
const double	EPSILON = 1e-12
const double	kAlpha = 0.3

Detailed Description

Sweep-line, Constrained Delauney Triangulation (CDT) See: Domiter, V.

Author

Mason Green mason.nosp@m..gre.nosp@m.en@gm.nosp@m.ail..nosp@m.com

and Zalik, B.(2008)'Sweep-line algorithm for constrained Delaunay triangulation', International Journal of Geographical Information Science

"FlipScan" Constrained Edge Algorithm invented by Thomas Åhlén, thahl.nosp@m.en@g.nosp@m.mail..nosp@m.com

Function Documentation

Cross() [1/2]

Point p2t::Cross ( const Point & a, double s )

inline

Perform the cross product on a point and a scalar.

In 2D this produces a point.

Cross() [2/2]

Point p2t::Cross ( double s, const Point & a )

inline

Perform the cross product on a scalar and a point.

In 2D this produces a point.

Orient2d()

Orientation p2t::Orient2d	(	const Point &	pa,
		const Point &	pb,
		const Point &	pc )

Forumla to calculate signed area
Positive if CCW
Negative if CW
0 if collinear
.

A[P1,P2,P3]  =  (x1*y2 - y1*x2) + (x2*y3 - y2*x3) + (x3*y1 - y3*x1)
             =  (x1-x3)*(y2-y3) - (y1-y3)*(x2-x3)