LineSegment2d.java
package org.djutils.draw.line;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Locale;
import org.djutils.draw.DrawRuntimeException;
import org.djutils.draw.Drawable2d;
import org.djutils.draw.bounds.Bounds2d;
import org.djutils.draw.point.DirectedPoint2d;
import org.djutils.draw.point.Point2d;
import org.djutils.exceptions.Throw;
/**
* LineSegment2d is a line segment bound by 2 end points in 2D-space. A line segment stores the order in which it has been
* created, so the end points are known as 'start' and 'end'.
* <p>
* Copyright (c) 2020-2024 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
* BSD-style license. See <a href="https://djutils.org/docs/current/djutils/licenses.html">DJUTILS License</a>.
* </p>
* @author <a href="https://www.tudelft.nl/averbraeck">Alexander Verbraeck</a>
* @author <a href="https://www.tudelft.nl/pknoppers">Peter Knoppers</a>
*/
public class LineSegment2d implements Drawable2d, LineSegment<Point2d, DirectedPoint2d>
{
/** */
private static final long serialVersionUID = 20210121L;
/** The start x-coordinate. */
@SuppressWarnings("checkstyle:visibilitymodifier")
public final double startX;
/** The start y-coordinate. */
@SuppressWarnings("checkstyle:visibilitymodifier")
public final double startY;
/** The end x-coordinate. */
@SuppressWarnings("checkstyle:visibilitymodifier")
public final double endX;
/** The end y-coordinate. */
@SuppressWarnings("checkstyle:visibilitymodifier")
public final double endY;
/**
* Construct a new LineSegment2d from four coordinates.
* @param startX double; the x-coordinate of the start point
* @param startY double; the y-coordinate of the start point
* @param endX double; the x-coordinate of the end point
* @param endY double; the y-coordinate of the end point
* @throws DrawRuntimeException when (startX,startY) is equals end (endX,endY)
*/
public LineSegment2d(final double startX, final double startY, final double endX, final double endY)
throws DrawRuntimeException
{
Throw.when(startX == endX && startY == endY, DrawRuntimeException.class, "Start and end may not be equal");
this.startX = startX;
this.startY = startY;
this.endX = endX;
this.endY = endY;
}
/**
* Construct a new LineSegment2d from a Point2d and two coordinates.
* @param start Point2d; the start point
* @param endX double; the x-coordinate of the end point
* @param endY double; the y-coordinate of the end point
* @throws NullPointerException when start is null
* @throws DrawRuntimeException when start has the exact coordinates endX, endY
*/
public LineSegment2d(final Point2d start, final double endX, final double endY)
throws NullPointerException, DrawRuntimeException
{
this(Throw.whenNull(start, "start").x, start.y, endX, endY);
}
/**
* Construct a new LineSegment2d from two coordinates and a Point2d.
* @param startX double; the x-coordinate of the start point
* @param startY double; the y-coordinate of the start point
* @param end Point2d; the end point
* @throws NullPointerException when end is null
* @throws DrawRuntimeException when end has the exact coordinates startX, startY
*/
public LineSegment2d(final double startX, final double startY, final Point2d end)
throws NullPointerException, DrawRuntimeException
{
this(startX, startY, Throw.whenNull(end, "end").x, end.y);
}
/**
* Construct a new LineSegment2d from two Point2d objects.
* @param start Point2d; the start point
* @param end Point2d; the end point
* @throws NullPointerException when start is null
* @throws DrawRuntimeException when start has the exact coordinates endX, endY
*/
public LineSegment2d(final Point2d start, final Point2d end) throws NullPointerException, DrawRuntimeException
{
this(Throw.whenNull(start, "start").x, start.y, Throw.whenNull(end, "end").x, end.y);
}
@Override
public Point2d getStartPoint()
{
return new Point2d(this.startX, this.startY);
}
@Override
public Point2d getEndPoint()
{
return new Point2d(this.endX, this.endY);
}
@Override
public double getLength()
{
return Math.hypot(this.endX - this.startX, this.endY - this.startY);
}
@Override
public Iterator<? extends Point2d> getPoints()
{
return Arrays.stream(new Point2d[] {getStartPoint(), getEndPoint()}).iterator();
}
@Override
public int size()
{
return 2;
}
@Override
public Bounds2d getBounds()
{
return new Bounds2d(Math.min(this.startX, this.endX), Math.max(this.startX, this.endX),
Math.min(this.startY, this.endY), Math.max(this.startY, this.endY));
}
@Override
public DirectedPoint2d getLocationExtended(final double position) throws DrawRuntimeException
{
Throw.when(Double.isNaN(position) || Double.isInfinite(position), DrawRuntimeException.class,
"position must be finite");
double dX = this.endX - this.startX;
double dY = this.endY - this.startY;
double length = Math.hypot(dX, dY);
return new DirectedPoint2d(this.startX + position * dX / length, this.startY + position * dY / length,
Math.atan2(dY, dX));
}
@Override
public Point2d closestPointOnSegment(final Point2d point) throws NullPointerException
{
Throw.whenNull(point, "point");
return point.closestPointOnLine(this.startX, this.startY, this.endX, this.endY, true, true);
}
@Override
public LineSegment2d reverse()
{
return new LineSegment2d(this.endX, this.endY, this.startX, this.startY);
}
@Override
public Point2d projectOrthogonal(final Point2d point) throws NullPointerException
{
Throw.whenNull(point, "point");
return point.closestPointOnLine(this.startX, this.startY, this.endX, this.endY, null, null);
}
@Override
public Point2d projectOrthogonalExtended(final Point2d point)
{
Throw.whenNull(point, "point");
return point.closestPointOnLine(this.startX, this.startY, this.endX, this.endY, false, false);
}
@Override
public double projectOrthogonalFractional(final Point2d point) throws NullPointerException
{
Throw.whenNull(point, "point");
return point.fractionalPositionOnLine(this.startX, this.startY, this.endX, this.endY, null, null);
}
@Override
public double projectOrthogonalFractionalExtended(final Point2d point) throws NullPointerException
{
Throw.whenNull(point, "point");
return point.fractionalPositionOnLine(this.startX, this.startY, this.endX, this.endY, false, false);
}
@Override
public String toString()
{
return toString("%f", false);
}
@Override
public String toString(final String doubleFormat, final boolean doNotIncludeClassName)
{
String format = String.format("%1$s[startX=%2$s, startY=%2$s - endX=%2%s, endY=%2$s]",
doNotIncludeClassName ? "" : "LineSegment2d ", doubleFormat);
return String.format(Locale.US, format, this.startX, this.startY, this.endX, this.endY);
}
@Override
public int hashCode()
{
final int prime = 31;
int result = 1;
long temp;
temp = Double.doubleToLongBits(this.endX);
result = prime * result + (int) (temp ^ (temp >>> 32));
temp = Double.doubleToLongBits(this.endY);
result = prime * result + (int) (temp ^ (temp >>> 32));
temp = Double.doubleToLongBits(this.startX);
result = prime * result + (int) (temp ^ (temp >>> 32));
temp = Double.doubleToLongBits(this.startY);
result = prime * result + (int) (temp ^ (temp >>> 32));
return result;
}
@Override
@SuppressWarnings("checkstyle:needbraces")
public boolean equals(final Object obj)
{
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
LineSegment2d other = (LineSegment2d) obj;
if (Double.doubleToLongBits(this.endX) != Double.doubleToLongBits(other.endX))
return false;
if (Double.doubleToLongBits(this.endY) != Double.doubleToLongBits(other.endY))
return false;
if (Double.doubleToLongBits(this.startX) != Double.doubleToLongBits(other.startX))
return false;
if (Double.doubleToLongBits(this.startY) != Double.doubleToLongBits(other.startY))
return false;
return true;
}
}