JTS Topology Suite version 1.13

com.vividsolutions.jts.algorithm
Class CGAlgorithmsDD

java.lang.Object
  extended by com.vividsolutions.jts.algorithm.CGAlgorithmsDD

public class CGAlgorithmsDD
extends java.lang.Object

Implements basic computational geometry algorithms using DD arithmetic.

Author:
Martin Davis

Constructor Summary
CGAlgorithmsDD()
           
 
Method Summary
static Coordinate intersection(Coordinate p1, Coordinate p2, Coordinate q1, Coordinate q2)
          Computes an intersection point between two lines using DD arithmetic.
static int orientationIndex(Coordinate p1, Coordinate p2, Coordinate q)
          Returns the index of the direction of the point q relative to a vector specified by p1-p2.
static int signOfDet2x2(DD x1, DD y1, DD x2, DD y2)
          Computes the sign of the determinant of the 2x2 matrix with the given entries.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

CGAlgorithmsDD

public CGAlgorithmsDD()
Method Detail

orientationIndex

public static int orientationIndex(Coordinate p1,
                                   Coordinate p2,
                                   Coordinate q)
Returns the index of the direction of the point q relative to a vector specified by p1-p2.

Parameters:
p1 - the origin point of the vector
p2 - the final point of the vector
q - the point to compute the direction to
Returns:
1 if q is counter-clockwise (left) from p1-p2

signOfDet2x2

public static int signOfDet2x2(DD x1,
                               DD y1,
                               DD x2,
                               DD y2)
Computes the sign of the determinant of the 2x2 matrix with the given entries.

Returns:
-1 if the determinant is negative,

intersection

public static Coordinate intersection(Coordinate p1,
                                      Coordinate p2,
                                      Coordinate q1,
                                      Coordinate q2)
Computes an intersection point between two lines using DD arithmetic. Currently does not handle case of parallel lines.

Parameters:
p1 -
p2 -
q1 -
q2 -
Returns:

JTS Topology Suite version 1.13