Represents a triangle in a triangulation. More...

#include <Triangle2.h>

Public Member Functions
	Triangle2 ()
	Default constructor.

double	getArea25D () const
	Get the 2.5D area of the triangle. More...

double	getArea2D () const
	Get the 2D area of the triangle. More...

Point2	getBarycenter () const
	Get the barycenter of the triangle. More...

Point2	getCircumcenter (CircumcenterQuality &ccq, bool bForceExact=false) const
	Get the circumcenter of the triangle. More...

Point2 *	getCorner (const int idx) const
	Retrieves the specified corner of the triangle. More...

void	getCorners (Point2 &p0, Point2 &p1, Point2 *&p2) const
	Retrieves all three triangle corners. More...

double	getInteriorAngle25D (int idx) const
	Get the interior 2.5D angle. More...

double	getInteriorAngle2D (int idx) const
	Get interior 2D angle. More...

int	getIntraTriangleIndex (const Point2 p0, const Point2 p1) const
	Get the index of the specified edge. More...

int	getIntraTriangleIndex (const Point2 *pCorner) const
	Get the index of the specified corner. More...

int	getIntraTriangleIndex (const Triangle2 *pNeig) const
	Get the index of the specified neighbor triangle. More...

int	getMaxIndex () const
	Get the index of the largest edge. More...

double	getMaxSqEdgeLen2D () const
	Get the maximum squared 2D edge length. More...

int	getMinIndex () const
	Get the index of the smallest edge. More...

Vector2	getNormalVector () const
	Get the normal vector of the triangle. More...

Triangle2 *	getOppositeTriangle (const int idx) const
	Get the neighbor triangle at the specified index. More...

double	getSquaredEdgeLength25D (int idx) const
	Get the squared 2.5D length of the specified edge. More...

double	getSquaredEdgeLength2D (int idx) const
	Get the squared 2D length of the specified edge. More...

bool	hasOn (const Point2 &q) const
	Check if the triangle includes the specified point. More...

bool	hasOnEdge (int idx, const Point2 &q) const
	Check if an edge includes the specified point. More...

bool	hasVertex (const Point2 &q) const
	Check if the specified point coincides with a corner of the triangle. More...

bool	hasVertex (const Point2 *pVtx) const
	Check if the specified vertex is a corner of the triangle. More...

void	setProperties (Point2 pI, Point2 pJ, Point2 *pK)
	Set all corners. More...

void	setVertexPointer (const int idx, Point2 *pVtx)
	Set a corner. More...

Friends
CLASS_DECLSPEC friend std::ostream &	operator<< (std::ostream &stream, const Triangle2 &c)
	Output operator for Triangle2. More...

void	registerTriangles (Triangle2 fromTriangle, int ith, Triangle2 toTriangle, int jth)

Detailed Description

Triangle2 represents a triangle in a Fade_2D triangulation.

Details:

A Triangle2 contains three pointers to its corners, each represented by a Point2. The corners are counterclockwise ordered and can be retrieved using the intra-triangle indices 0, 1 and 2.
A Triangle2 contains three pointers to its neighbor-triangles which are also retrieved through the intra-triangle indices. The i-th neighbor triangle is the one opposite to the i-th corner.

Triangle2: The corners are counterclockwise; the i-th neighbor triangle is the one opposite to the i-th corner of a triangle

See also: A C++ example about accessing and drawing elements of a triangulation

Member Function Documentation

◆ getArea25D()

double GEOM_FADE25D::Triangle2::getArea25D ( ) const

Computes the 2.5D area of the current triangle.

Returns: the 2.5D area of the current triangle.

◆ getArea2D()

double GEOM_FADE25D::Triangle2::getArea2D ( ) const

Computes the 2D area of the current triangle.

Returns: The area of the current triangle in 2D.

Note: This method ignores the z-coordinate.

◆ getBarycenter()

Point2 GEOM_FADE25D::Triangle2::getBarycenter ( ) const

Computes and returns the barycenter the this triangle.

Returns: The barycenter of the current triangle.

◆ getCircumcenter()

Point2 GEOM_FADE25D::Triangle2::getCircumcenter	(	CircumcenterQuality &	ccq,
		bool	bForceExact = `false`
	)		const

Returns the circumcenter (the center of the circumcircle) of the current triangle.

Parameters

[out]	ccq	Indicates the quality of the computed circumcenter and is one of CCQ_INEXACT, CCQ_EXACT, and CCQ_OUT_OF_BOUNDS.
[in]	bForceExact	If `true`, forces exact computation with multiple-precision arithmetic.

Returns: The circumcenter of the Triangle2, with a z-coordinate of 0.0.

Attention: The circumcenter of a nearly collinear triangle has extremely large coordinates. While multiple-precision arithmetic is used for such cases, the result might still exceed the precision limits of double-precision arithmetic. In such scenarios, a finite point is returned, and ccq is set to CCQ_OUT_OF_BOUNDS. To avoid these cases, insert four dummy vertices around the triangulation at coordinates 10 times larger than the domain of the data points. This restricts the Voronoi cells to a manageable range.

◆ getCorner()

Point2 * GEOM_FADE25D::Triangle2::getCorner ( const int idx ) const

inline

Retrieves a Point2* corresponding to the triangle corner specified by the intra-triangle index idx.

The counterclockwise ordering of intra-triangle indices for the corners of a triangle

Parameters

idx	The intra-triangle index of the corner (0, 1, or 2).

Returns: A pointer to the corner at index idx of the triangle.

◆ getCorners()

void GEOM_FADE25D::Triangle2::getCorners	(	Point2 *&	p0,
		Point2 *&	p1,
		Point2 *&	p2
	)		const

inline

Retrieves the three corners of the Triangle2.

Parameters

[out] p0,p1,p2 Pointers to the three corners

◆ getInteriorAngle25D()

double GEOM_FADE25D::Triangle2::getInteriorAngle25D ( int idx ) const

Returns the interior 2.5D angle at the vertex specified by the intra-triangle index idx.

Returns: The interior 2.5D angle at the vertex at index idx.

◆ getInteriorAngle2D()

double GEOM_FADE25D::Triangle2::getInteriorAngle2D ( int idx ) const

Returns the interior 2D angle at the vertex specified by the intra-triangle index idx.

Returns: The interior 2D angle at the vertex at the intra-triangle index idx

Note: This method ignores the z-coordinate.

◆ getIntraTriangleIndex() [1/3]

int GEOM_FADE25D::Triangle2::getIntraTriangleIndex	(	const Point2 *	p0,
		const Point2 *	p1
	)		const

inline

Retrieves the intra-triangle index of the edge defined by (p0,p1) in the current triangle.

Example: The edge defined by the vertex pair (p0, p1) corresponds to the intra-triangle index 0.

Parameters

p0,p1 Two corners specifying an edge of the current triangle. The order of p0 and p1 does not matter.

Returns: The intra-triangle index of the edge (p0, p1) in the current triangle. This index corresponds to the intra-triangle index of the vertex opposite to this edge.

◆ getIntraTriangleIndex() [2/3]

int GEOM_FADE25D::Triangle2::getIntraTriangleIndex ( const Point2 * pCorner ) const

inline

Retrieves the index of the triangle corner pCorner.

The intra-triangle index of pCorner is 1.

Parameters

pCorner A pointer to a corner in the current triangle.

Returns: The intra-triangle index (0,1 or 2) of pCorner in the current triangle.

◆ getIntraTriangleIndex() [3/3]

int GEOM_FADE25D::Triangle2::getIntraTriangleIndex ( const Triangle2 * pNeig ) const

inline

Retrieves the intra-triangle index of the neighbor triangle pNeig.

The intra-triangle index of pNeig in the current triangle is 0.

Parameters

pNeig A neighbor triangle of the current triangle.

Returns: The intra-triangle index of the triangle pNeig in the current triangle. This index corresponds to the intra-triangle index of the vertex opposite to pNeig in the current triangle.

◆ getMaxIndex()

int GEOM_FADE25D::Triangle2::getMaxIndex ( ) const

Returns the index of edge with the largest 2D length.

Returns: The index of the edge with the largest 2D length.

◆ getMaxSqEdgeLen2D()

double GEOM_FADE25D::Triangle2::getMaxSqEdgeLen2D ( ) const

Computes and returns the largest squared 2D edge length among the triangle's edges.

Returns: the largest squared 2D edge length.

Note: This method ignores the z-coordinate.

◆ getMinIndex()

int GEOM_FADE25D::Triangle2::getMinIndex ( ) const

Returns the intra-triangle index of the edge with the smallest 2D length.

Returns: The intra-triangle index of the edge with the smallest 2D length.

◆ getNormalVector()

Vector2 GEOM_FADE25D::Triangle2::getNormalVector ( ) const

Computes the normalized normal vector of the current triangle.

Returns: The normalized normal vector.

◆ getOppositeTriangle()

Triangle2 * GEOM_FADE25D::Triangle2::getOppositeTriangle ( const int idx ) const

inline

Retrieves the neighbor triangle opposite to the corner at the specified intra-triangle index idx.

Neighbor triangles: The i-th neighbor triangle is the one opposite to the i-th corner of a triangle

Parameters

idx	The intra-triangle index specifying the opposite corner (0, 1 or 2)

Returns: The neighbor triangle at index idx, if any; NULL otherwise.

◆ getSquaredEdgeLength25D()

double GEOM_FADE25D::Triangle2::getSquaredEdgeLength25D ( int idx ) const

Computes the squared 2.5D length of the edge at index idx.

Parameters

idx	The index of the edge for which the squared 2.5D length is computed.

Returns: The squared 2.5D length of the edge at index idx.

◆ getSquaredEdgeLength2D()

double GEOM_FADE25D::Triangle2::getSquaredEdgeLength2D ( int idx ) const

Computes the squared 2D length of the edge at index idx.

Parameters

idx	The index of the edge for which the squared length is computed.

Returns: The squared 2D length of the edge at index idx.

Note: This method ignores the z-coordinate.

◆ hasOn()

bool GEOM_FADE25D::Triangle2::hasOn ( const Point2 & q ) const

Checks if the specified point q is on the current triangle.

Parameters

q	The point to test.

Returns: true if q lies on the current triangle, false otherwise.

This is a 2D test; it ignores the z coordinate.

◆ hasOnEdge()

bool GEOM_FADE25D::Triangle2::hasOnEdge	(	int	idx,
		const Point2 &	q
	)		const

Checks if the specified point q lies exactly on the edge at index idx of the current triangle.

Returns: true if the point q lies exactly on the edge at index idx, false otherwise.

Note: This is a 2D test; it ignores the z coordinate.

◆ hasVertex() [1/2]

bool GEOM_FADE25D::Triangle2::hasVertex ( const Point2 & q ) const

Checks if the specified point q coincides with any corner of the current triangle.

Parameters

q	The Point2 object to search for.

Returns: true if q coincides with a corner of the current Triangle2, false otherwise.

◆ hasVertex() [2/2]

bool GEOM_FADE25D::Triangle2::hasVertex ( const Point2 * pVtx ) const

Checks if the specified vertex pVtx is a corner of the current triangle.

Parameters

pVtx	A pointer to a Point2 object to search for

Returns: true if pVtx is a corner of the current Triangle2, false otherwise.

◆ setProperties()

void GEOM_FADE25D::Triangle2::setProperties	(	Point2 *	pI,
		Point2 *	pJ,
		Point2 *	pK
	)

inline

Sets the three corner points. This method is mostly for internal use.

Parameters

pI,pJ,pK The corners to be assigned.

◆ setVertexPointer()

void GEOM_FADE25D::Triangle2::setVertexPointer	(	const int	idx,
		Point2 *	pVtx
	)

inline

Sets the corner at the intra-triangle index idx. This method is mostly for internal use.

Parameters

idx	The intra-triangle index (0, 1, or 2).
pVtx	A pointer to a Point2 object

Friends And Related Function Documentation

◆ operator<<

CLASS_DECLSPEC friend std::ostream& operator<<	(	std::ostream &	stream,
		const Triangle2 &	c
	)

friend

Prints a Triangle2 object to an output stream.

Parameters

stream	The output stream to which the Triangle2 object is written.
c	The Triangle2 object to be written to the stream.

Returns: A reference to the output stream after writing the Triangle2 object.

The documentation for this class was generated from the following file:

Triangle2.h

Public Member Functions

Friends

Detailed Description

Member Function Documentation

◆ getArea25D()

◆ getArea2D()

◆ getBarycenter()

◆ getCircumcenter()

◆ getCorner()

◆ getCorners()

◆ getInteriorAngle25D()

◆ getInteriorAngle2D()

◆ getIntraTriangleIndex() [1/3]

◆ getIntraTriangleIndex() [2/3]

◆ getIntraTriangleIndex() [3/3]

◆ getMaxIndex()

◆ getMaxSqEdgeLen2D()

◆ getMinIndex()

◆ getNormalVector()

◆ getOppositeTriangle()

◆ getSquaredEdgeLength25D()

◆ getSquaredEdgeLength2D()

◆ hasOn()

◆ hasOnEdge()

◆ hasVertex() [1/2]

◆ hasVertex() [2/2]

◆ setProperties()

◆ setVertexPointer()

Friends And Related Function Documentation

◆ operator<<