Linestring2D (Variable type)

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Properties specific to Linestring2D variables
Functions that use the Linestring2D type

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Linestring2D (Variable type)

In french: Polyligne2D

The Linestring2D type is used to define all the advanced characteristics of a linestring defined with 2D coordinates. You can define and change the characteristics of this 2D linestring using different WLanguage properties.

Characteristics of a 2D linestring:

A 2D linestring is a set of contiguous segments represented on a Cartesian plane. It is defined by a sequence of points. In mathematics, this is referred to as "polygonal chain".

If the start and end points of a linestring are the same, the linestring is "closed".
If the linestring does not self-intersect, the linestring is "simple".
A simple and closed linestring is referred to as a "LinearRing".

Remark: For more details on the declaration of this type of variable and the use of WLanguage properties, see Declaring a variable.

Example

MyLine is Linestring2D

// Add points to linestring
// 1. Standard syntax 
Linestring2DAddPoint(MyLine, 31, 21)
// 2. Prefix syntax
MyPoint is Point2D
MyPoint.X = 31
MyPoint.Y = 21 
MyLine.Point.Add(MyPoint)

MyLine is Linestring2D

// Add points to linestring
// 1. Standard syntax
Linestring2DAddPoint(MyLine, 32, 22)
Linestring2DAddPoint(MyLine, 134, 12)

// 2. Prefix syntax
MyLine.AddPoint(32, 22)
MyLine.AddPoint(134, 12)

Properties

Properties specific to Linestring2D variables

The following properties can be used to manipulate a 2D linestring:

Property name	Type used	Effect

Point	Array of Point2D	Linestring points.
Type	Integer constant	Type of the current geometry. For a linestring defined with 2D coordinates, corresponds to the gtLinestring2D constant. Remark: Until version 2024 Update 2, this constant was named stLinestring2D. This property is available in read-only.

Remarks

Functions that use the Linestring2D type

The following functions use Linestring2D variables:


GeometryArea	Calculates the area of a given geometry.
GeometryContain	Determines if geometry A contains geometry B.
GeometryConvexHull	Calculates the convex hull of the specified geometry.
GeometryCorrect	Returns a corrected version of the specified geometry.
GeometryCover	Determines if geometry A covers geometry B.
GeometryCoveredBy	Determines if every point of geometry A lies inside or on the boundary of geometry B.
GeometryCross	Compares two geometries and determines if their intersection spatially crosses.
GeometryDifference	Returns a geometry representing the difference between two geometries.
GeometryDisjoint	Determines whether two geometries are disjoint, i.e. whether their intersection is empty.
GeometryDistance	Calculates the distance between two geometries.
GeometryEqual	Determines whether two geometries are spatially equal, i.e. whether the first geometry is included in the second, and vice versa.
GeometryIntersect	Checks whether two geometries have a non-empty intersection.
GeometryIntersection	Returns a geometry representing the intersection of two geometries.
GeometryIsValid	Checks whether the specified geometry is valid according to the OGC rules.
GeometryLength	Calculates the length of a given geometry.
GeometryOverlap	Determines whether two geometries overlap.
GeometryPerimeter	Calculates the perimeter of a given geometry (polygon or multipolygon).
GeometrySerializeDSV	Serializes a geometry using the specified DSV format.
GeometrySerializeWKT	Serializes a geometry using the Well-Known Text (WKT) format.
GeometrySymmetricDifference	Calculates the symmetric difference between two geometries.
GeometryTouch	Determines whether two geometries touch.
GeometryUnion	Returns a geometry corresponding to the union of two geometries.
GeometryWithin	Determines whether geometry A is completely within geometry B (i.e., geometry B completely contains geometry A).
Linestring2DAddPoint	Adds a new point to a 2D linestring.