Represents a line segment defined by two Coordinates. Provides methods to compute various geometric properties and relationships of line segments. This class is designed to be easily mutable (to the extent of having its contained points public). This supports a common pattern of reusing a single LineSegment object as a way of computing segment properties on the segments defined by arrays or lists of Coordinates. More...

Inheritance diagram for NetTopologySuite.Geometries.LineSegment:

Public Member Functions
	LineSegment (Coordinate p0, Coordinate p1)
	Creates an instance of this class using two coordinates More...

	LineSegment (LineSegment ls)
	Creates an instance of this class using another instance More...

	LineSegment ()

	LineSegment (double x0, double y0, double x1, double y1)
	Creates an instance of this class More...

Coordinate	GetCoordinate (int i)

void	SetCoordinates (LineSegment ls)

void	SetCoordinates (Coordinate p0, Coordinate p1)

int	OrientationIndex (LineSegment seg)
	Determines the orientation of a LineSegment relative to this segment. The concept of orientation is specified as follows: Given two line segments A and L, A is to the left of a segment L if A lies wholly in the closed half-plane lying to the left of L A is to the right of a segment L if A lies wholly in the closed half-plane lying to the right of L otherwise, A has indeterminate orientation relative to L. This happens if A is collinear with L or if A crosses the line determined by L. More...

int	OrientationIndex (Coordinate p)
	Determines the orientation index of a Coordinate relative to this segment. The orientation index is as defined in CGAlgorithms.ComputeOrientation. /summary> More...

void	Reverse ()
	Reverses the direction of the line segment. More...

void	Normalize ()
	Puts the line segment into a normalized form. This is useful for using line segments in maps and indexes when topological equality rather than exact equality is desired. More...

double	Distance (LineSegment ls)
	Computes the distance between this line segment and another one. More...

double	Distance (Coordinate p)
	Computes the distance between this line segment and a point. More...

double	DistancePerpendicular (Coordinate p)
	Computes the perpendicular distance between the (infinite) line defined by this line segment and a point. More...

Coordinate	PointAlong (double segmentLengthFraction)
	Computes the Coordinate that lies a given fraction along the line defined by this segment. More...

Coordinate	PointAlongOffset (double segmentLengthFraction, double offsetDistance)
	Computes the Coordinate that lies a given More...

double	ProjectionFactor (Coordinate p)
	Computes the Projection Factor for the projection of the point p onto this LineSegment. The Projection Factor is the constant r by which the vector for this segment must be multiplied to equal the vector for the projection of `p` on the line defined by this segment. The projection factor will lie in the range `(-inf, +inf)`, or be `NaN` if the line segment has zero length. More...

double	SegmentFraction (Coordinate inputPt)
	Computes the fraction of distance (in [0.0, 1.0]) that the projection of a point occurs along this line segment. If the point is beyond either ends of the line segment, the closest fractional value (0.0 or 1.0) is returned. More...

Coordinate	Project (Coordinate p)
	Compute the projection of a point onto the line determined by this line segment. Note that the projected point may lie outside the line segment. If this is the case, the projection factor will lie outside the range [0.0, 1.0]. More...

LineSegment	Project (LineSegment seg)
	Project a line segment onto this line segment and return the resulting line segment. The returned line segment will be a subset of the target line line segment. This subset may be null, if the segments are oriented in such a way that there is no projection. Note that the returned line may have zero length (i.e. the same endpoints). This can happen for instance if the lines are perpendicular to one another. More...

Coordinate	ClosestPoint (Coordinate p)
	Computes the closest point on this line segment to another point. More...

Coordinate[]	ClosestPoints (LineSegment line)
	Computes the closest points on a line segment. More...

Coordinate	Intersection (LineSegment line)
	Computes an intersection point between two segments, if there is one. There may be 0, 1 or many intersection points between two segments. If there are 0, null is returned. If there is 1 or more, a single one is returned (chosen at the discretion of the algorithm). If more information is required about the details of the intersection, the {RobustLineIntersector} class should be used. More...

Coordinate	LineIntersection (LineSegment line)
	Computes the intersection point of the lines defined by two segments, if there is one. More...

ILineString	ToGeometry (IGeometryFactory geomFactory)
	Creates a LineString with the same coordinates as this segment More...

override bool	Equals (object o)
	Returns `true` if `o` has the same values for its points. More...

int	CompareTo (object o)
	Compares this object with the specified object for order. Uses the standard lexicographic ordering for the points in the LineSegment. More...

bool	EqualsTopologically (LineSegment other)
	Returns `true` if `other` is topologically equal to this LineSegment (e.g. irrespective of orientation). More...

override string	ToString ()

override int	GetHashCode ()
	Return HashCode. More...

Static Public Member Functions
static bool	operator== (LineSegment obj1, LineSegment obj2)

static bool	operator!= (LineSegment obj1, LineSegment obj2)

Properties
Coordinate	P1 `[get, set]`
	The end-point More...

Coordinate	P0 `[get, set]`
	The start-point More...

double	Length `[get]`
	Computes the length of the line segment. More...

bool	IsHorizontal `[get]`
	Tests whether the segment is horizontal. More...

bool	IsVertical `[get]`
	Tests whether the segment is vertical. More...

double	Angle `[get]`
	summary>The midpoint of the segment More...

Coordinate	MidPoint `[get]`

Detailed Description

Represents a line segment defined by two Coordinates. Provides methods to compute various geometric properties and relationships of line segments. This class is designed to be easily mutable (to the extent of having its contained points public). This supports a common pattern of reusing a single LineSegment object as a way of computing segment properties on the segments defined by arrays or lists of Coordinates.

Constructor & Destructor Documentation

NetTopologySuite.Geometries.LineSegment.LineSegment	(	Coordinate	p0,
		Coordinate	p1
	)

Creates an instance of this class using two coordinates

Parameters

p0	The start-point
p1	The end-point

NetTopologySuite.Geometries.LineSegment.LineSegment ( LineSegment ls )

Creates an instance of this class using another instance

Parameters

ls

NetTopologySuite.Geometries.LineSegment.LineSegment ( )

NetTopologySuite.Geometries.LineSegment.LineSegment	(	double	x0,
		double	y0,
		double	x1,
		double	y1
	)

Creates an instance of this class

Parameters

x0
y0
x1
y1

Member Function Documentation

Coordinate NetTopologySuite.Geometries.LineSegment.ClosestPoint ( Coordinate p )

Computes the closest point on this line segment to another point.

Parameters

p	The point to find the closest point to.

Returns: A Coordinate which is the closest point on the line segment to the point p.

Coordinate [] NetTopologySuite.Geometries.LineSegment.ClosestPoints ( LineSegment line )

Computes the closest points on a line segment.

Parameters

line

Returns: A pair of Coordinates which are the closest points on the line segments.

int NetTopologySuite.Geometries.LineSegment.CompareTo ( object o )

Compares this object with the specified object for order. Uses the standard lexicographic ordering for the points in the LineSegment.

Parameters

o	The `LineSegment` with which this `LineSegment` is being compared.

Returns: A negative integer, zero, or a positive integer as this LineSegment is less than, equal to, or greater than the specified LineSegment.

double NetTopologySuite.Geometries.LineSegment.Distance ( LineSegment ls )

Computes the distance between this line segment and another one.

Parameters

ls

Returns

double NetTopologySuite.Geometries.LineSegment.Distance ( Coordinate p )

Computes the distance between this line segment and a point.

double NetTopologySuite.Geometries.LineSegment.DistancePerpendicular ( Coordinate p )

Computes the perpendicular distance between the (infinite) line defined by this line segment and a point.

Parameters

p

Returns

override bool NetTopologySuite.Geometries.LineSegment.Equals ( object o )

Returns true if o has the same values for its points.

Parameters

o	A `LineSegment` with which to do the comparison.

Returns: true if o is a LineSegment with the same values for the x and y ordinates.

bool NetTopologySuite.Geometries.LineSegment.EqualsTopologically ( LineSegment other )

Returns true if other is topologically equal to this LineSegment (e.g. irrespective of orientation).

Parameters

other A LineSegment with which to do the comparison.

Returns: true if other is a LineSegment with the same values for the x and y ordinates.

Coordinate NetTopologySuite.Geometries.LineSegment.GetCoordinate ( int i )

Parameters

i

Returns

override int NetTopologySuite.Geometries.LineSegment.GetHashCode ( )

Return HashCode.

Coordinate NetTopologySuite.Geometries.LineSegment.Intersection ( LineSegment line )

Computes an intersection point between two segments, if there is one. There may be 0, 1 or many intersection points between two segments. If there are 0, null is returned. If there is 1 or more, a single one is returned (chosen at the discretion of the algorithm). If more information is required about the details of the intersection, the {RobustLineIntersector} class should be used.

Parameters

line	A line segment

Returns: An intersection point, or null if there is none.

RobustLineIntersector

Coordinate NetTopologySuite.Geometries.LineSegment.LineIntersection ( LineSegment line )

Computes the intersection point of the lines defined by two segments, if there is one.

There may be 0, 1 or an infinite number of intersection points between two lines. If there is a unique intersection point, it is returned. Otherwise, null is returned. If more information is required about the details of the intersection, the RobustLineIntersector class should be used.

Parameters

line	A line segment defining a straight line

Returns: An intersection point, or null if there is none or an infinite number

See also: RobustLineIntersector

void NetTopologySuite.Geometries.LineSegment.Normalize ( )

Puts the line segment into a normalized form. This is useful for using line segments in maps and indexes when topological equality rather than exact equality is desired.

static bool NetTopologySuite.Geometries.LineSegment.operator!=	(	LineSegment	obj1,
		LineSegment	obj2
	)

static

Parameters

obj1
obj2

Returns

static bool NetTopologySuite.Geometries.LineSegment.operator==	(	LineSegment	obj1,
		LineSegment	obj2
	)

static

Parameters

obj1
obj2

Returns

int NetTopologySuite.Geometries.LineSegment.OrientationIndex ( LineSegment seg )

Determines the orientation of a LineSegment relative to this segment. The concept of orientation is specified as follows: Given two line segments A and L, A is to the left of a segment L if A lies wholly in the closed half-plane lying to the left of L A is to the right of a segment L if A lies wholly in the closed half-plane lying to the right of L otherwise, A has indeterminate orientation relative to L. This happens if A is collinear with L or if A crosses the line determined by L.

Parameters

seg	The `LineSegment` to compare.

Returns: 1 if seg is to the left of this segment, -1 if seg is to the right of this segment, 0 if seg has indeterminate orientation relative to this segment.

int NetTopologySuite.Geometries.LineSegment.OrientationIndex ( Coordinate p )

Determines the orientation index of a Coordinate relative to this segment. The orientation index is as defined in CGAlgorithms.ComputeOrientation. /summary>

Parameters

seg	the LineSegment to compare

Returns

See also

CGAlgorithms::computeOrientation(Coordinate, Coordinate, Coordinate)

Returns

1 if p is to the left of this segment
-1 if p is to the right of this segment
0 if p is collinear with this segment

"

Coordinate NetTopologySuite.Geometries.LineSegment.PointAlong ( double segmentLengthFraction )

Computes the Coordinate that lies a given fraction along the line defined by this segment.

A fraction of

0.0

returns the start point of the segment; A fraction of

1.0

returns the end point of the segment. If the fraction is < 0.0 or > 1.0 the point returned will lie before the start or beyond the end of the segment.

Parameters

segmentLengthFraction the fraction of the segment length along the line

Returns: the point at that distance

Coordinate NetTopologySuite.Geometries.LineSegment.PointAlongOffset	(	double	segmentLengthFraction,
		double	offsetDistance
	)

Computes the Coordinate that lies a given

A fraction along the line defined by this segment and offset from the segment by a given distance. A fraction of

0.0

offsets from the start point of the segment; A fraction of

1.0

offsets from the end point of the segment. The computed point is offset to the left of the line if the offset distance is positive, to the right if negative.

Parameters

segmentLengthFraction	the fraction of the segment length along the line
offsetDistance	the distance the point is offset from the segment

(positive is to the left, negative is to the right)

Returns: the point at that distance and offset

Exceptions

ApplicationException if the segment has zero length

Coordinate NetTopologySuite.Geometries.LineSegment.Project ( Coordinate p )

Compute the projection of a point onto the line determined by this line segment. Note that the projected point may lie outside the line segment. If this is the case, the projection factor will lie outside the range [0.0, 1.0].

Parameters

p

Returns

LineSegment NetTopologySuite.Geometries.LineSegment.Project ( LineSegment seg )

Project a line segment onto this line segment and return the resulting line segment. The returned line segment will be a subset of the target line line segment. This subset may be null, if the segments are oriented in such a way that there is no projection. Note that the returned line may have zero length (i.e. the same endpoints). This can happen for instance if the lines are perpendicular to one another.

Parameters

seg	The line segment to project.

Returns: The projected line segment, or null if there is no overlap.

double NetTopologySuite.Geometries.LineSegment.ProjectionFactor ( Coordinate p )

Computes the Projection Factor for the projection of the point p onto this LineSegment. The Projection Factor is the constant r by which the vector for this segment must be multiplied to equal the vector for the projection of p on the line defined by this segment. The projection factor will lie in the range (-inf, +inf), or be NaN if the line segment has zero length.

Parameters

p	The point to compute the factor for

Returns: The projection factor for the point

void NetTopologySuite.Geometries.LineSegment.Reverse ( )

Reverses the direction of the line segment.

double NetTopologySuite.Geometries.LineSegment.SegmentFraction ( Coordinate inputPt )

Computes the fraction of distance (in [0.0, 1.0]) that the projection of a point occurs along this line segment. If the point is beyond either ends of the line segment, the closest fractional value (0.0 or 1.0) is returned.

Essentially, this is the ProjectionFactor(Coordinate) clamped to the range [0.0, 1.0].

Parameters

inputPt the point

Returns: the fraction along the line segment the projection of the point occurs

void NetTopologySuite.Geometries.LineSegment.SetCoordinates ( LineSegment ls )

Parameters

ls

void NetTopologySuite.Geometries.LineSegment.SetCoordinates	(	Coordinate	p0,
		Coordinate	p1
	)

Parameters

p0
p1

ILineString NetTopologySuite.Geometries.LineSegment.ToGeometry ( IGeometryFactory geomFactory )

Creates a LineString with the same coordinates as this segment

Parameters

geomFactory the geometery factory to use

Returns: A LineString with the same geometry as this segment

override string NetTopologySuite.Geometries.LineSegment.ToString ( )

Returns

Property Documentation

double NetTopologySuite.Geometries.LineSegment.Angle

get

summary>The midpoint of the segment

Returns: The angle this segment makes with the x-axis (in radians).

bool NetTopologySuite.Geometries.LineSegment.IsHorizontal

get

Tests whether the segment is horizontal.

Returns: true if the segment is horizontal.

bool NetTopologySuite.Geometries.LineSegment.IsVertical

get

Tests whether the segment is vertical.

Returns: true if the segment is vertical.

double NetTopologySuite.Geometries.LineSegment.Length

get

Computes the length of the line segment.

Returns: The length of the line segment.

Coordinate NetTopologySuite.Geometries.LineSegment.P0

getset

The start-point

Coordinate NetTopologySuite.Geometries.LineSegment.P1

getset

The end-point

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

NetTopologySuite/NetTopologySuite/Geometries/LineSegment.cs

Public Member Functions

Static Public Member Functions

Properties

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Property Documentation