com.caffeineowl.graphics

Class DistUtils

java.lang.Object

com.caffeineowl.graphics.DistUtils

public final class DistUtils
extends Object

Utility functions to deal with lines, line segments, etc.

Author:

Adrian Colomitchi

Constructor Summary

Constructors

Constructor and Description
DistUtils()

Method Summary

Methods

Modifier and Type	Method and Description
static double	pointToLineEucDist(double pointX, double pointY, double startX, double startY, double endX, double endY) Computes the euclidian distance between a point and its' projection on a line (distance between a point and the line).
static double	pointToLineSqEucDist(double pointX, double pointY, double startX, double startY, double endX, double endY) Computes the square of the euclidian distance between a point and its' projection on a line (the distance between a point and the line).
static double	pointToPointCbsvDist(double p1x, double p1y, double p2x, double p2y) The the chess (Chebyshev) distance between two points.
static double	pointToPointEucDist(double p1x, double p1y, double p2x, double p2y) The the euclidian distance between two points.
static double	pointToPointMnhtDist(double p1x, double p1y, double p2x, double p2y) The the Manhattan distance between two points.
static double	pointToPointSqEucDist(double p1x, double p1y, double p2x, double p2y) The square of the euclidian distance between two points.
static double	pointToSegEucDist(double pointX, double pointY, double startX, double startY, double endX, double endY) Computes the the minimum euclidian distance to the segment's point which is the closest to the original point.
static double	pointToSegSqEucDist(double pointX, double pointY, double startX, double startY, double endX, double endY) Computes the the minimum squared euclidian distance to the segment's point which is the closest to the original point.

Methods inherited from class java.lang.Object

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

Constructor Detail

DistUtils

public DistUtils()

Method Detail

pointToPointSqEucDist

public static final double pointToPointSqEucDist(double p1x,
                           double p1y,
                           double p2x,
                           double p2y)

The square of the euclidian distance between two points.

Parameters:

p1x - x coordinate of the first point

p1y - y coordinate of the first point

p2x - x coordinate of the second point

p2y - y coordinate of the second point

pointToPointEucDist

public static final double pointToPointEucDist(double p1x,
                         double p1y,
                         double p2x,
                         double p2y)

The the euclidian distance between two points. Computes it by calling Math.sqrt(@link #pointToLineSqEucDist(double, double, double, double, double, double)) (i.e. more computational extensive than computing the square of the distance).

Parameters:

p1x - x coordinate of the first point

p1y - y coordinate of the first point

p2x - x coordinate of the second point

p2y - y coordinate of the second point

pointToPointMnhtDist

public static final double pointToPointMnhtDist(double p1x,
                          double p1y,
                          double p2x,
                          double p2y)

The the Manhattan distance between two points.

Parameters:

p1x - x coordinate of the first point

p1y - y coordinate of the first point

p2x - x coordinate of the second point

p2y - y coordinate of the second point

pointToPointCbsvDist

public static final double pointToPointCbsvDist(double p1x,
                          double p1y,
                          double p2x,
                          double p2y)

The the chess (Chebyshev) distance between two points.

Parameters:

p1x - x coordinate of the first point

p1y - y coordinate of the first point

p2x - x coordinate of the second point

p2y - y coordinate of the second point

pointToLineSqEucDist

public static final double pointToLineSqEucDist(double pointX,
                          double pointY,
                          double startX,
                          double startY,
                          double endX,
                          double endY)

Computes the square of the euclidian distance between a point and its' projection on a line (the distance between a point and the line). no matter if the projection falls outside the [startX, startY]...[endX, endY] segment.

Parameters:

pointX - the x coordinate of the point

pointY - the y coordinate of the point

startX - the x coordinate of the first point on the line

startY - the y coordinate of the first point on the line

endX - the x coordinate of the second point on the line

endY - the y coordinate of the second point on the line

pointToLineEucDist

public static final double pointToLineEucDist(double pointX,
                        double pointY,
                        double startX,
                        double startY,
                        double endX,
                        double endY)

Computes the euclidian distance between a point and its' projection on a line (distance between a point and the line). Calls the Math.sqrt(pointToLineSqEucDist), which makes this method more computational intensive than computing the square of the distance.

Parameters:

pointX - the x coordinate of the point

pointY - the y coordinate of the point

startX - the x coordinate of the first point on the line

startY - the y coordinate of the first point on the line

endX - the x coordinate of the second point on the line

endY - the y coordinate of the second point on the line

pointToSegSqEucDist

public static final double pointToSegSqEucDist(double pointX,
                         double pointY,
                         double startX,
                         double startY,
                         double endX,
                         double endY)

Computes the the minimum squared euclidian distance to the segment's point which is the closest to the original point. That is, if the projection of the given point falls on the segment, the squared distance to the projection is returned. Otherwise, the method returns the squared distance to the end of the segment that is closest to the given point.

Parameters:

pointX - the x coordinate of the point

pointY - the y coordinate of the point

startX - the x coordinate of the segment's start

startY - the y coordinate of the segment's start

endX - the x coordinate of the segment's end

endY - the y coordinate of the segment's end

Returns:

the squared euclidian distance from the given point to the closest point on the segment.

pointToSegEucDist

public static final double pointToSegEucDist(double pointX,
                       double pointY,
                       double startX,
                       double startY,
                       double endX,
                       double endY)

Computes the the minimum euclidian distance to the segment's point which is the closest to the original point. Returns the square root of the pointToSegSqEucDist(double, double, double, double, double, double).