java.lang.Object
- org.locationtech.jts.algorithm.Orientation

```
public class Orientation
extends Object
```
Functions to compute the orientation of basic geometric structures including point triplets (triangles) and rings. Orientation is a fundamental property of planar geometries (and more generally geometry on two-dimensional manifolds).
Orientation is notoriously subject to numerical precision errors in the case of collinear or nearly collinear points. JTS uses extended-precision arithmetic to increase the robustness of the computation.

Author:

Martin Davis

Field Summary

Fields
Modifier and Type	Field	Description
`static int`	`CLOCKWISE`	A value that indicates an orientation of clockwise, or a right turn.
`static int`	`COLLINEAR`	A value that indicates an orientation of collinear, or no turn (straight).
`static int`	`COUNTERCLOCKWISE`	A value that indicates an orientation of counterclockwise, or a left turn.
`static int`	`LEFT`	A value that indicates an orientation of counterclockwise, or a left turn.
`static int`	`RIGHT`	A value that indicates an orientation of clockwise, or a right turn.
`static int`	`STRAIGHT`	A value that indicates an orientation of collinear, or no turn (straight).

Constructor Summary

Constructors
Constructor Description

Orientation()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static int`	`index(Coordinate p1, Coordinate p2, Coordinate q)`	Returns the orientation index of the direction of the point `q` relative to a directed infinite line specified by `p1-p2`.
`static boolean`	`isCCW(Coordinate[] ring)`	Computes whether a ring defined by an array of `Coordinate`s is oriented counter-clockwise.
`static boolean`	`isCCW(CoordinateSequence ring)`	Computes whether a ring defined by an `CoordinateSequence` is oriented counter-clockwise.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - CLOCKWISE
```
public static final int CLOCKWISE
```
    A value that indicates an orientation of clockwise, or a right turn.
    
    See Also:
    
    Constant Field Values
  - RIGHT
```
public static final int RIGHT
```
    A value that indicates an orientation of clockwise, or a right turn.
    
    See Also:
    
    Constant Field Values
  - COUNTERCLOCKWISE
```
public static final int COUNTERCLOCKWISE
```
    A value that indicates an orientation of counterclockwise, or a left turn.
    
    See Also:
    
    Constant Field Values
  - LEFT
```
public static final int LEFT
```
    A value that indicates an orientation of counterclockwise, or a left turn.
    
    See Also:
    
    Constant Field Values
  - COLLINEAR
```
public static final int COLLINEAR
```
    A value that indicates an orientation of collinear, or no turn (straight).
    
    See Also:
    
    Constant Field Values
  - STRAIGHT
```
public static final int STRAIGHT
```
    A value that indicates an orientation of collinear, or no turn (straight).
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - Orientation
```
public Orientation()
```
- Method Detail
  - index
```
public static int index(Coordinate p1,
                        Coordinate p2,
                        Coordinate q)
```
    Returns the orientation index of the direction of the point q relative to a directed infinite line specified by p1-p2. The index indicates whether the point lies to the LEFT or RIGHT of the line, or lies on it COLLINEAR. The index also indicates the orientation of the triangle formed by the three points ( COUNTERCLOCKWISE, CLOCKWISE, or STRAIGHT )
    
    Parameters:
    
    p1 - the origin point of the line vector
    
    p2 - the final point of the line vector
    
    q - the point to compute the direction to
    
    Returns:
    
    -1 ( CLOCKWISE or RIGHT ) if q is clockwise (right) from p1-p2; 1 ( COUNTERCLOCKWISE or LEFT ) if q is counter-clockwise (left) from p1-p2; 0 ( COLLINEAR or STRAIGHT ) if q is collinear with p1-p2
  - isCCW
```
public static boolean isCCW(Coordinate[] ring)
```
    Computes whether a ring defined by an array of Coordinates is oriented counter-clockwise.
    
    The list of points is assumed to have the first and last points equal.
    This will handle coordinate lists which contain repeated points.
    This algorithm is only guaranteed to work with valid rings. If the ring is invalid (e.g. self-crosses or touches), the computed result may not be correct.
    Parameters:
    
    ring - an array of Coordinates forming a ring
    
    Returns:
    
    true if the ring is oriented counter-clockwise.
    
    Throws:
    
    IllegalArgumentException - if there are too few points to determine orientation (< 4)
  - isCCW
```
public static boolean isCCW(CoordinateSequence ring)
```
    Computes whether a ring defined by an CoordinateSequence is oriented counter-clockwise.
    
    The list of points is assumed to have the first and last points equal.
    This will handle coordinate lists which contain repeated points.
    This algorithm is only guaranteed to work with valid rings. If the ring is invalid (e.g. self-crosses or touches), the computed result may not be correct.
    Parameters:
    
    ring - a CoordinateSequence forming a ring
    
    Returns:
    
    true if the ring is oriented counter-clockwise.
    
    Throws:
    
    IllegalArgumentException - if there are too few points to determine orientation (< 4)

Class Orientation

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

CLOCKWISE

RIGHT

COUNTERCLOCKWISE

LEFT

COLLINEAR

STRAIGHT

Constructor Detail

Orientation

Method Detail

index

isCCW

isCCW