de.erichseifert.gral.util

Class GeometryUtils

java.lang.Object

de.erichseifert.gral.util.GeometryUtils

public abstract class GeometryUtils
extends java.lang.Object

Abstract class that represents a collection of utility functions concerning geometry.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	GeometryUtils.PathSegment Utility data class for the values of the segments in a geometric shape.

Field Summary

Fields

Modifier and Type	Field and Description
static double	EPSILON Precision.
static double	EPSILON_SQ Precision squared.

Method Summary

Modifier and Type	Method and Description
static java.util.List<GeometryUtils.PathSegment>	getSegments(java.awt.Shape shape) Returns a list of a shape's segments as they are returned by its path iterator.
static java.awt.Shape	getShape(java.util.List<GeometryUtils.PathSegment> segments, boolean isDouble) Constructs a geometric shape from a list of path segments.
static java.awt.geom.Area	grow(java.awt.Shape s, double offset) Expand or shrink a shape in all directions by a defined offset.
static java.awt.geom.Area	grow(java.awt.Shape s, double offset, int join, float miterlimit) Expand or shrink a shape in all directions by a defined offset.
static java.awt.geom.Point2D	intersection(java.awt.geom.Line2D l1, java.awt.geom.Line2D l2) Returns the intersection point of two lines.
static java.util.List<java.awt.geom.Point2D>	intersection(java.awt.Shape s1, java.awt.Shape s2) Returns all intersection points of two shapes.
static java.awt.geom.Area	punch(java.awt.geom.Area shapeArea, double gap, boolean rounded, java.awt.geom.Point2D pointPos, java.awt.Shape pointShape) Subtract a specified geometric area of data points from another shape to yield gaps.
static java.awt.Shape	reverse(java.awt.Shape shape) Returns a clone of a specified shape which has a reversed order of the points, lines and curves.
static java.awt.geom.Line2D[]	shapeToLines(java.awt.Shape path, boolean swapped) Returns the line fragments of the specified Shape.

Methods inherited from class java.lang.Object

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

Field Detail

EPSILON

public static final double EPSILON

Precision.

See Also:

Constant Field Values

EPSILON_SQ

public static final double EPSILON_SQ

Precision squared.

See Also:

Constant Field Values

Method Detail

shapeToLines

public static java.awt.geom.Line2D[] shapeToLines(java.awt.Shape path,
                                                  boolean swapped)

Returns the line fragments of the specified Shape.

Parameters:

path - Shape to be divided.

swapped - Invert segment direction.

Returns:

Array of lines.

intersection

public static java.util.List<java.awt.geom.Point2D> intersection(java.awt.Shape s1,
                                                                 java.awt.Shape s2)

Returns all intersection points of two shapes.

Parameters:

s1 - First shape

s2 - Second shape

Returns:

Intersection points, or empty array if no intersections were found

intersection

public static java.awt.geom.Point2D intersection(java.awt.geom.Line2D l1,
                                                 java.awt.geom.Line2D l2)

Returns the intersection point of two lines.

Parameters:

l1 - First line

l2 - Second line

Returns:

Intersection point, or null if no intersection was found

grow

public static java.awt.geom.Area grow(java.awt.Shape s,
                                      double offset)

Expand or shrink a shape in all directions by a defined offset.

Parameters:

s - Shape

offset - Offset

Returns:

New shape that was expanded or shrunk by the specified amount

grow

public static java.awt.geom.Area grow(java.awt.Shape s,
                                      double offset,
                                      int join,
                                      float miterlimit)

Expand or shrink a shape in all directions by a defined offset.

Parameters:

s - Shape

offset - Offset to expand/shrink

join - Method for handling edges (see BasicStroke)

miterlimit - Limit for miter joining method

Returns:

New shape that is expanded or shrunk by the specified amount

punch

public static java.awt.geom.Area punch(java.awt.geom.Area shapeArea,
                                       double gap,
                                       boolean rounded,
                                       java.awt.geom.Point2D pointPos,
                                       java.awt.Shape pointShape)

Subtract a specified geometric area of data points from another shape to yield gaps.

Parameters:

shapeArea - Shape from which to subtract.

gap - Size of the gap.

rounded - Gap corners will be rounded if true.

pointPos - Position of the data point

pointShape - Shape of the data point

Returns:

Shape with punched holes

getSegments

public static java.util.List<GeometryUtils.PathSegment> getSegments(java.awt.Shape shape)

Returns a list of a shape's segments as they are returned by its path iterator.

Parameters:

shape - Shape to be iterated.

Returns:

A list of path segment objects.

getShape

public static java.awt.Shape getShape(java.util.List<GeometryUtils.PathSegment> segments,
                                      boolean isDouble)

Constructs a geometric shape from a list of path segments.

Parameters:

segments - List of path segments.

isDouble - true if the shape contents should be stored with double values, false if they should be stored as float.

Returns:

A geometric shape.

reverse

public static java.awt.Shape reverse(java.awt.Shape shape)

Returns a clone of a specified shape which has a reversed order of the points, lines and curves.

Parameters:

shape - Original shape.

Returns:

Shape with reversed direction.