de.javagl.geom

Class Points

java.lang.Object

de.javagl.geom.Points

public class Points
extends Object

Utility methods related to points

Method Summary

Modifier and Type	Method and Description
static Point2D	add(Point2D p0, Point2D p1, Point2D result) Computes the sum the given points and stores the result in the given result point.
static Point2D	addScaled(Point2D p0, double factor, Point2D p1, Point2D result) Computes p0 + factor * p1 and stores the result in the given result point.
static Comparator<Point2D>	byAngleComparator(double centerX, double centerY) Creates a comparator that compares points by the angle that the line between the specified center and the point has to the x-axis.
static Comparator<Point2D>	byAngleComparator(Point2D center) Creates a comparator that compares points by the angle that the line between the given center and the point has to the x-axis.
static Comparator<Point2D>	byDistanceComparator(double x, double y) Returns a comparator that compares points by their distance to the specified reference point
static Comparator<Point2D>	byDistanceComparator(Point2D reference) Returns a comparator that compares points by their distance to the given reference point
static Comparator<Point2D>	byDistanceToLineComparator(double x0, double y0, double x1, double y1) Returns a comparator that compares points by their distance to the specified line
static Comparator<Point2D>	byDistanceToLineComparator(Line2D line) Returns a comparator that compares points by their distance to the specified line
static Comparator<Point2D>	byDistanceToLineComparator(Point2D p0, Point2D p1) Returns a comparator that compares points by their distance to the specified line
static Comparator<Point2D>	byDistanceToOriginComparator() Returns a comparator that compares points by their distance to the origin
static Comparator<Point2D>	colexicographicalComparator() Returns a comparator that compares points colexicographically.
static Rectangle2D	computeBounds(Iterable<? extends Point2D> points) Compute the bounding box of the given points
static Point2D	computeCenterOfGravity(Iterable<? extends Point2D> points) Computes the center of gravity of the given sequence of points.
static Point2D	interpolate(double x0, double y0, double x1, double y1, double alpha, Point2D result) Interpolates linearly between the specified points, and stores the result in the given result point.
static Point2D	interpolate(Point2D p0, Point2D p1, double alpha, Point2D result) Interpolates linearly between the given points, and stores the result in the given result point.
static Point2D	inverseTransform(AffineTransform at, Point2D pSrc, Point2D pDst) Transforms the given point with the inverse of the given transform, and stores the result in the given destination point.
static Comparator<Point2D>	lexicographicalComparator() Returns a comparator that compares points lexicographically.
static Point2D	scale(Point2D p0, double factor, Point2D result) Scales the given point with the given factor and stores the result in the given result point.
static Point2D	sub(Point2D p0, Point2D p1, Point2D result) Computes the difference between the given points and stores the result in the given result point.
static String	toString(Point2D point) Creates a short string representation of the given point
static String	toString(Point2D point, Locale locale, String format) Creates a short string representation of the given point, using the given format for the coordinates
static String	toString(Point2D point, String format) Creates a short string representation of the given point, using the given format for the coordinates
static List<Point2D>	transform(AffineTransform at, Iterable<? extends Point2D> points) Transforms all the given points with the given affine transform, and returns the results

Methods inherited from class java.lang.Object

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

Method Detail

colexicographicalComparator

public static Comparator<Point2D> colexicographicalComparator()

Returns a comparator that compares points colexicographically. That means that it compares the points by their y-coordinate, and, if these are equal, by their x-coordinate

Returns:

The comparator

lexicographicalComparator

public static Comparator<Point2D> lexicographicalComparator()

Returns a comparator that compares points lexicographically. That means that it compares the points by their x-coordinate, and, if these are equal, by their y-coordinate

Returns:

The comparator

byAngleComparator

public static Comparator<Point2D> byAngleComparator(Point2D center)

Creates a comparator that compares points by the angle that the line between the given center and the point has to the x-axis.

Parameters:

center - The center

Returns:

The comparator

byAngleComparator

public static Comparator<Point2D> byAngleComparator(double centerX,
                                                    double centerY)

Creates a comparator that compares points by the angle that the line between the specified center and the point has to the x-axis.

Parameters:

centerX - The x-coordinate of the center

centerY - The y-coordinate of the center

Returns:

The comparator

byDistanceComparator

public static Comparator<Point2D> byDistanceComparator(double x,
                                                       double y)

Returns a comparator that compares points by their distance to the specified reference point

Parameters:

x - The x-coordinate of the reference point

y - The y-coordinate of the reference point

Returns:

The comparator

byDistanceComparator

public static Comparator<Point2D> byDistanceComparator(Point2D reference)

Returns a comparator that compares points by their distance to the given reference point

Parameters:

reference - The reference point

Returns:

The comparator

byDistanceToOriginComparator

public static Comparator<Point2D> byDistanceToOriginComparator()

Returns a comparator that compares points by their distance to the origin

Returns:

The comparator

byDistanceToLineComparator

public static Comparator<Point2D> byDistanceToLineComparator(Line2D line)

Returns a comparator that compares points by their distance to the specified line

Parameters:

line - The line

Returns:

The comparator

byDistanceToLineComparator

public static Comparator<Point2D> byDistanceToLineComparator(Point2D p0,
                                                             Point2D p1)

Returns a comparator that compares points by their distance to the specified line

Parameters:

p0 - The start point of the line

p1 - The end point of the line

Returns:

The comparator

byDistanceToLineComparator

public static Comparator<Point2D> byDistanceToLineComparator(double x0,
                                                             double y0,
                                                             double x1,
                                                             double y1)

Returns a comparator that compares points by their distance to the specified line

Parameters:

x0 - The x-coordinate of the start point of the line

y0 - The y-coordinate of the start point of the line

x1 - The x-coordinate of the end point of the line

y1 - The y-coordinate of the end point of the line

Returns:

The comparator

sub

public static Point2D sub(Point2D p0,
                          Point2D p1,
                          Point2D result)

Computes the difference between the given points and stores the result in the given result point. If the given result point is null, a new point will be created and returned.

Parameters:

p0 - The first point

p1 - The second point

result - The result

Returns:

The result

add

public static Point2D add(Point2D p0,
                          Point2D p1,
                          Point2D result)

Computes the sum the given points and stores the result in the given result point. If the given result point is null, a new point will be created and returned.

Parameters:

p0 - The first point

p1 - The second point

result - The result

Returns:

The result

scale

public static Point2D scale(Point2D p0,
                            double factor,
                            Point2D result)

Scales the given point with the given factor and stores the result in the given result point. If the given result point is null, a new point will be created and returned.

Parameters:

p0 - The point

factor - The scaling factor

result - The result

Returns:

The result

addScaled

public static Point2D addScaled(Point2D p0,
                                double factor,
                                Point2D p1,
                                Point2D result)

Computes p0 + factor * p1 and stores the result in the given result point. If the given result point is null, a new point will be created and returned.

Parameters:

p0 - The first point

factor - The scaling factor for the second point

p1 - The second point

result - The result

Returns:

The result

interpolate

public static Point2D interpolate(Point2D p0,
                                  Point2D p1,
                                  double alpha,
                                  Point2D result)

Interpolates linearly between the given points, and stores the result in the given result point. If the given result point is null, a new point will be created and returned.

Parameters:

p0 - The first point

p1 - The second point

alpha - The position between the points (usually between 0 and 1)

result - The result

Returns:

The result

interpolate

public static Point2D interpolate(double x0,
                                  double y0,
                                  double x1,
                                  double y1,
                                  double alpha,
                                  Point2D result)

Interpolates linearly between the specified points, and stores the result in the given result point. If the given result point is null, a new point will be created and returned.

Parameters:

x0 - The x-coordinate of the first point

y0 - The y-coordinate of the first point

x1 - The x-coordinate of the second point

y1 - The y-coordinate of the second point

alpha - The position between the points (usually between 0 and 1)

result - The result

Returns:

The result

inverseTransform

public static Point2D inverseTransform(AffineTransform at,
                                       Point2D pSrc,
                                       Point2D pDst)

Transforms the given point with the inverse of the given transform, and stores the result in the given destination point. If the given destination point is null, a new point will be created and returned.

Parameters:

at - The affine transform

pSrc - The source point

pDst - The destination point

Returns:

The destination point

Throws:

IllegalArgumentException - If the given transform is not invertible

transform

public static List<Point2D> transform(AffineTransform at,
                                      Iterable<? extends Point2D> points)

Transforms all the given points with the given affine transform, and returns the results

Parameters:

at - The affine transform

points - The input points

Returns:

The transformed points

computeBounds

public static Rectangle2D computeBounds(Iterable<? extends Point2D> points)

Compute the bounding box of the given points

Parameters:

points - The input points

Returns:

The bounding box of the given points

computeCenterOfGravity

public static Point2D computeCenterOfGravity(Iterable<? extends Point2D> points)

Computes the center of gravity of the given sequence of points. This is simply the average of all points. If the given sequence is empty, then null is returned.

Parameters:

points - The points

Returns:

The center of gravity

toString

public static String toString(Point2D point)

Creates a short string representation of the given point

Parameters:

point - The point

Returns:

The string

toString

public static String toString(Point2D point,
                              String format)

Creates a short string representation of the given point, using the given format for the coordinates

Parameters:

point - The point

format - The format

Returns:

The string

toString

public static String toString(Point2D point,
                              Locale locale,
                              String format)

Creates a short string representation of the given point, using the given format for the coordinates

Parameters:

point - The point

locale - The locale

format - The format

Returns:

The string