org.openimaj.math.geometry.shape.util

Class PolygonUtils

java.lang.Object

org.openimaj.math.geometry.shape.util.PolygonUtils

public class PolygonUtils
extends Object

PolygonUtils is a Java version of the General Polygon Clipper algorithm developed by Alan Murta (gpc@cs.man.ac.uk). The home page for the original source can be found at http://www.cs.man.ac.uk/aig/staff/alan/software/.

polyClass: Some of the public methods below take a polyClass argument. This java.lang.Class object is assumed to implement the Polygon interface and have a no argument constructor. This was done so that the user of the algorithm could create their own classes that implement the Polygon interface and still uses this algorithm.

Implementation Note: The converted algorithm does support the difference operation, but a public method has not been provided and it has not been tested. To do so, simply follow what has been done for intersection.

Author:

Dan Bridenbecker, Solution Engineering, Inc.

Field Summary

Fields

Modifier and Type	Field and Description
static int	ABOVE ABOVE
static int	BELOW BELOW
static int	CLIP CLIP
static int	LEFT LEFT
static int	RIGHT RIGHT
static int	SUBJ SUBJ

Constructor Summary

Constructors

Constructor and Description
PolygonUtils() Creates a new instance of PolygonUtils

Method Summary

Modifier and Type	Method and Description
Polygon	intersection(Polygon p1, Polygon p2) Return the intersection of p1 and p2 where the return type is of PolyDefault.
Polygon	intersection(Polygon p1, Polygon p2, Class<Polygon> polyClass) Return the intersection of p1 and p2 where the return type is of polyClass.
static int	NEXT_INDEX(int i, int n)
static int	PREV_INDEX(int i, int n)
Polygon	union(Polygon p1, Polygon p2) Return the union of p1 and p2 where the return type is of PolyDefault.
Polygon	union(Polygon p1, Polygon p2, Class<Polygon> polyClass) Return the union of p1 and p2 where the return type is of polyClass.
Polygon	xor(Polygon p1, Polygon p2) Return the xor of p1 and p2 where the return type is of PolyDefault.
Polygon	xor(Polygon p1, Polygon p2, Class<Polygon> polyClass) Return the xor of p1 and p2 where the return type is of polyClass.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LEFT

public static final int LEFT

LEFT

See Also:

Constant Field Values

RIGHT

public static final int RIGHT

RIGHT

See Also:

Constant Field Values

ABOVE

public static final int ABOVE

ABOVE

See Also:

Constant Field Values

BELOW

public static final int BELOW

BELOW

See Also:

Constant Field Values

CLIP

public static final int CLIP

CLIP

See Also:

Constant Field Values

SUBJ

public static final int SUBJ

SUBJ

See Also:

Constant Field Values

Constructor Detail

PolygonUtils

public PolygonUtils()

Creates a new instance of PolygonUtils

Method Detail

intersection

public Polygon intersection(Polygon p1,
                            Polygon p2,
                            Class<Polygon> polyClass)

Return the intersection of p1 and p2 where the return type is of polyClass. See the note in the class description for more on polyClass.

Parameters:

p1 - One of the polygons to perform the intersection with

p2 - One of the polygons to perform the intersection with

polyClass - The type of Polygon to return

Returns:

the resultant polygon

union

public Polygon union(Polygon p1,
                     Polygon p2,
                     Class<Polygon> polyClass)

Return the union of p1 and p2 where the return type is of polyClass. See the note in the class description for more on polyClass.

Parameters:

p1 - One of the polygons to perform the union with

p2 - One of the polygons to perform the union with

polyClass - The type of Polygon to return

Returns:

the resultant polygon

xor

public Polygon xor(Polygon p1,
                   Polygon p2,
                   Class<Polygon> polyClass)

Return the xor of p1 and p2 where the return type is of polyClass. See the note in the class description for more on polyClass.

Parameters:

p1 - One of the polygons to perform the xor with

p2 - One of the polygons to perform the xor with

polyClass - The type of Polygon to return

Returns:

the resultant polygon

intersection

public Polygon intersection(Polygon p1,
                            Polygon p2)

Return the intersection of p1 and p2 where the return type is of PolyDefault.

Parameters:

p1 - One of the polygons to perform the intersection with

p2 - One of the polygons to perform the intersection with

Returns:

the resultant polygon

union

public Polygon union(Polygon p1,
                     Polygon p2)

Return the union of p1 and p2 where the return type is of PolyDefault.

Parameters:

p1 - One of the polygons to performt he union with

p2 - One of the polygons to performt he union with

Returns:

the resultant polygon

xor

public Polygon xor(Polygon p1,
                   Polygon p2)

Return the xor of p1 and p2 where the return type is of PolyDefault.

Parameters:

p1 - One of the polygons to perform the xor with

p2 - One of the polygons to perform the xor with

Returns:

the resultant polygon

PREV_INDEX

public static int PREV_INDEX(int i,
                             int n)

Parameters:

i -

n -

Returns:

previous index

NEXT_INDEX

public static int NEXT_INDEX(int i,
                             int n)

Parameters:

i -

n -

Returns:

next index