
JTS Topology Suite version 1.12  
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SUMMARY: NESTED  FIELD  CONSTR  METHOD  DETAIL: FIELD  CONSTR  METHOD 
java.lang.Object com.vividsolutions.jts.triangulate.quadedge.QuadEdge
public class QuadEdge
A class that represents the edge data structure which implements the quadedge algebra. The quadedge algebra was described in a wellknown paper by Guibas and Stolfi, "Primitives for the manipulation of general subdivisions and the computation of Voronoi diagrams", ACM Transactions on Graphics, 4(2), 1985, 75123.
Each edge object is part of a quartet of 4 edges,
linked via their rot references.
Any edge in the group may be accessed using a series of rot()
operations.
Quadedges in a subdivision are linked together via their next references.
The linkage between the quadedge quartets determines the topology
of the subdivision.
The edge class does not contain separate information for vertice or faces; a vertex is implicitly defined as a ring of edges (created using the next field).
Method Summary  

static QuadEdge 
connect(QuadEdge a,
QuadEdge b)
Creates a new QuadEdge connecting the destination of a to the origin of b, in such a way that all three have the same left face after the connection is complete. 
void 
delete()
Marks this quadedge as being deleted. 
Vertex 
dest()
Gets the vertex for the edge's destination 
QuadEdge 
dNext()
Gets the next CCW edge around (into) the destination of this edge. 
QuadEdge 
dPrev()
Gets the next CW edge around (into) the destination of this edge. 
boolean 
equalsNonOriented(QuadEdge qe)
Tests if this quadedge and another have the same line segment geometry, regardless of orientation. 
boolean 
equalsOriented(QuadEdge qe)
Tests if this quadedge and another have the same line segment geometry with the same orientation. 
java.lang.Object 
getData()
Gets the external data value for this edge. 
double 
getLength()
Gets the length of the geometry of this quadedge. 
QuadEdge 
getPrimary()
Gets the primary edge of this quadedge and its sym. 
QuadEdge 
invRot()
Gets the dual of this edge, directed from its left to its right. 
boolean 
isLive()
Tests whether this edge has been deleted. 
QuadEdge 
lNext()
Gets the CCW edge around the left face following this edge. 
QuadEdge 
lPrev()
Gets the CCW edge around the left face before this edge. 
static QuadEdge 
makeEdge(Vertex o,
Vertex d)
Creates a new QuadEdge quartet from Vertex o to Vertex d. 
QuadEdge 
oNext()
Gets the next CCW edge around the origin of this edge. 
QuadEdge 
oPrev()
Gets the next CW edge around (from) the origin of this edge. 
Vertex 
orig()
Gets the vertex for the edge's origin 
QuadEdge 
rNext()
Gets the edge around the right face ccw following this edge. 
QuadEdge 
rot()
Gets the dual of this edge, directed from its right to its left. 
QuadEdge 
rPrev()
Gets the edge around the right face ccw before this edge. 
void 
setData(java.lang.Object data)
Sets the external data value for this edge. 
void 
setNext(QuadEdge next)
Sets the connected edge 
static void 
splice(QuadEdge a,
QuadEdge b)
Splices two edges together or apart. 
static void 
swap(QuadEdge e)
Turns an edge counterclockwise inside its enclosing quadrilateral. 
QuadEdge 
sym()
Gets the edge from the destination to the origin of this edge. 
LineSegment 
toLineSegment()
Creates a LineSegment representing the
geometry of this edge. 
java.lang.String 
toString()
Converts this edge to a WKT twopoint LINESTRING indicating the geometry of this edge. 
Methods inherited from class java.lang.Object 

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait 
Method Detail 

public static QuadEdge makeEdge(Vertex o, Vertex d)
Vertex
o to Vertex
d.
o
 the origin Vertexd
 the destination Vertex
public static QuadEdge connect(QuadEdge a, QuadEdge b)
public static void splice(QuadEdge a, QuadEdge b)
a
 an edge to spliceb
 an edge to splicepublic static void swap(QuadEdge e)
e
 the quadedge to turnpublic QuadEdge getPrimary()
Coordinate
ordering
public void setData(java.lang.Object data)
data
 an object containing external datapublic java.lang.Object getData()
public void delete()
public boolean isLive()
public void setNext(QuadEdge next)
nextEdge
 edgepublic final QuadEdge rot()
public final QuadEdge invRot()
public final QuadEdge sym()
public final QuadEdge oNext()
public final QuadEdge oPrev()
public final QuadEdge dNext()
public final QuadEdge dPrev()
public final QuadEdge lNext()
public final QuadEdge lPrev()
public final QuadEdge rNext()
public final QuadEdge rPrev()
public final Vertex orig()
public final Vertex dest()
public double getLength()
public boolean equalsNonOriented(QuadEdge qe)
qe
 a quadege
public boolean equalsOriented(QuadEdge qe)
qe
 a quadege
public LineSegment toLineSegment()
LineSegment
representing the
geometry of this edge.
public java.lang.String toString()
toString
in class java.lang.Object

JTS Topology Suite version 1.12  
PREV CLASS NEXT CLASS  FRAMES NO FRAMES  
SUMMARY: NESTED  FIELD  CONSTR  METHOD  DETAIL: FIELD  CONSTR  METHOD 