/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @author Denis M. Kishenko
* @version $Revision$
*/
package java.awt.geom;
import java.awt.Rectangle;
import java.awt.Shape;
import java.util.NoSuchElementException;
import org.apache.harmony.awt.internal.nls.Messages;
/**
* The Class Line2D represents a line whose data is given in high-precision
* values appropriate for graphical operations.
*
* @since Android 1.0
*/
public abstract class Line2D implements Shape, Cloneable {
/**
* The Class Float is the subclass of Line2D that has all of its data values
* stored with float-level precision.
*
* @since Android 1.0
*/
public static class Float extends Line2D {
/**
* The x coordinate of the starting point.
*/
public float x1;
/**
* The y coordinate of the starting point.
*/
public float y1;
/**
* The x coordinate of the end point.
*/
public float x2;
/**
* The y coordinate of the end point.
*/
public float y2;
/**
* Instantiates a new float-valued Line2D with its data values set to
* zero.
*/
public Float() {
}
/**
* Instantiates a new float-valued Line2D with the specified endpoints.
*
* @param x1
* the x coordinate of the starting point.
* @param y1
* the y coordinate of the starting point.
* @param x2
* the x coordinate of the end point.
* @param y2
* the y coordinate of the end point.
*/
public Float(float x1, float y1, float x2, float y2) {
setLine(x1, y1, x2, y2);
}
/**
* Instantiates a new float-valued Line2D with the specified endpoints.
*
* @param p1
* the starting point.
* @param p2
* the end point.
*/
public Float(Point2D p1, Point2D p2) {
setLine(p1, p2);
}
@Override
public double getX1() {
return x1;
}
@Override
public double getY1() {
return y1;
}
@Override
public double getX2() {
return x2;
}
@Override
public double getY2() {
return y2;
}
@Override
public Point2D getP1() {
return new Point2D.Float(x1, y1);
}
@Override
public Point2D getP2() {
return new Point2D.Float(x2, y2);
}
@Override
public void setLine(double x1, double y1, double x2, double y2) {
this.x1 = (float)x1;
this.y1 = (float)y1;
this.x2 = (float)x2;
this.y2 = (float)y2;
}
/**
* Sets the data values that define the line.
*
* @param x1
* the x coordinate of the starting point.
* @param y1
* the y coordinate of the starting point.
* @param x2
* the x coordinate of the end point.
* @param y2
* the y coordinate of the end point.
*/
public void setLine(float x1, float y1, float x2, float y2) {
this.x1 = x1;
this.y1 = y1;
this.x2 = x2;
this.y2 = y2;
}
public Rectangle2D getBounds2D() {
float rx, ry, rw, rh;
if (x1 < x2) {
rx = x1;
rw = x2 - x1;
} else {
rx = x2;
rw = x1 - x2;
}
if (y1 < y2) {
ry = y1;
rh = y2 - y1;
} else {
ry = y2;
rh = y1 - y2;
}
return new Rectangle2D.Float(rx, ry, rw, rh);
}
}
/**
* The Class Double is the subclass of Line2D that has all of its data
* values stored with double-level precision.
*
* @since Android 1.0
*/
public static class Double extends Line2D {
/**
* The x coordinate of the starting point.
*/
public double x1;
/**
* The y coordinate of the starting point.
*/
public double y1;
/**
* The x coordinate of the end point.
*/
public double x2;
/**
* The y coordinate of the end point.
*/
public double y2;
/**
* Instantiates a new double-valued Line2D with its data values set to
* zero.
*/
public Double() {
}
/**
* Instantiates a new double-valued Line2D with the specified endpoints.
*
* @param x1
* the x coordinate of the starting point.
* @param y1
* the y coordinate of the starting point.
* @param x2
* the x coordinate of the end point.
* @param y2
* the y coordinate of the end point.
*/
public Double(double x1, double y1, double x2, double y2) {
setLine(x1, y1, x2, y2);
}
/**
* Instantiates a new double-valued Line2D with the specified endpoints.
*
* @param p1
* the starting point.
* @param p2
* the end point.
*/
public Double(Point2D p1, Point2D p2) {
setLine(p1, p2);
}
@Override
public double getX1() {
return x1;
}
@Override
public double getY1() {
return y1;
}
@Override
public double getX2() {
return x2;
}
@Override
public double getY2() {
return y2;
}
@Override
public Point2D getP1() {
return new Point2D.Double(x1, y1);
}
@Override
public Point2D getP2() {
return new Point2D.Double(x2, y2);
}
@Override
public void setLine(double x1, double y1, double x2, double y2) {
this.x1 = x1;
this.y1 = y1;
this.x2 = x2;
this.y2 = y2;
}
public Rectangle2D getBounds2D() {
double rx, ry, rw, rh;
if (x1 < x2) {
rx = x1;
rw = x2 - x1;
} else {
rx = x2;
rw = x1 - x2;
}
if (y1 < y2) {
ry = y1;
rh = y2 - y1;
} else {
ry = y2;
rh = y1 - y2;
}
return new Rectangle2D.Double(rx, ry, rw, rh);
}
}
/*
* Line2D path iterator
*/
/**
* The subclass of PathIterator to traverse a Line2D.
*/
class Iterator implements PathIterator {
/**
* The x coordinate of the start line point.
*/
double x1;
/**
* The y coordinate of the start line point.
*/
double y1;
/**
* The x coordinate of the end line point.
*/
double x2;
/**
* The y coordinate of the end line point.
*/
double y2;
/**
* The path iterator transformation.
*/
AffineTransform t;
/**
* The current segment index.
*/
int index;
/**
* Constructs a new Line2D.Iterator for given line and transformation.
*
* @param l
* the source Line2D object.
* @param at
* the AffineTransform object to apply rectangle path.
*/
Iterator(Line2D l, AffineTransform at) {
this.x1 = l.getX1();
this.y1 = l.getY1();
this.x2 = l.getX2();
this.y2 = l.getY2();
this.t = at;
}
public int getWindingRule() {
return WIND_NON_ZERO;
}
public boolean isDone() {
return index > 1;
}
public void next() {
index++;
}
public int currentSegment(double[] coords) {
if (isDone()) {
// awt.4B=Iterator out of bounds
throw new NoSuchElementException(Messages.getString("awt.4B")); //$NON-NLS-1$
}
int type;
if (index == 0) {
type = SEG_MOVETO;
coords[0] = x1;
coords[1] = y1;
} else {
type = SEG_LINETO;
coords[0] = x2;
coords[1] = y2;
}
if (t != null) {
t.transform(coords, 0, coords, 0, 1);
}
return type;
}
public int currentSegment(float[] coords) {
if (isDone()) {
// awt.4B=Iterator out of bounds
throw new NoSuchElementException(Messages.getString("awt.4B")); //$NON-NLS-1$
}
int type;
if (index == 0) {
type = SEG_MOVETO;
coords[0] = (float)x1;
coords[1] = (float)y1;
} else {
type = SEG_LINETO;
coords[0] = (float)x2;
coords[1] = (float)y2;
}
if (t != null) {
t.transform(coords, 0, coords, 0, 1);
}
return type;
}
}
/**
* Instantiates a new Line2D.
*/
protected Line2D() {
}
/**
* Gets the x coordinate of the starting point.
*
* @return the x coordinate of the starting point.
*/
public abstract double getX1();
/**
* Gets the y coordinate of the starting point.
*
* @return the y coordinate of the starting point.
*/
public abstract double getY1();
/**
* Gets the x coordinate of the end point.
*
* @return the x2.
*/
public abstract double getX2();
/**
* Gets the y coordinate of the end point.
*
* @return the y coordinate of the end point.
*/
public abstract double getY2();
/**
* Gets the p the starting point.
*
* @return the p the starting point.
*/
public abstract Point2D getP1();
/**
* Gets the p end point.
*
* @return the p end point.
*/
public abstract Point2D getP2();
/**
* Sets the line's endpoints.
*
* @param x1
* the x coordinate of the starting point.
* @param y1
* the y coordinate of the starting point.
* @param x2
* the x coordinate of the end point.
* @param y2
* the y coordinate of the end point.
*/
public abstract void setLine(double x1, double y1, double x2, double y2);
/**
* Sets the line's endpoints.
*
* @param p1
* the starting point.
* @param p2
* the end point.
*/
public void setLine(Point2D p1, Point2D p2) {
setLine(p1.getX(), p1.getY(), p2.getX(), p2.getY());
}
/**
* Sets the line's endpoints by copying the data from another Line2D.
*
* @param line
* the Line2D to copy the endpoint data from.
*/
public void setLine(Line2D line) {
setLine(line.getX1(), line.getY1(), line.getX2(), line.getY2());
}
public Rectangle getBounds() {
return getBounds2D().getBounds();
}
/**
* Tells where the point is with respect to the line segment, given the
* orientation of the line segment. If the ray found by extending the line
* segment from its starting point is rotated, this method tells whether the
* ray should rotate in a clockwise direction or a counter-clockwise
* direction to hit the point first. The return value is 0 if the point is
* on the line segment, it's 1 if the point is on the ray or if the ray
* should rotate in a counter-clockwise direction to get to the point, and
* it's -1 if the ray should rotate in a clockwise direction to get to the
* point or if the point is on the line determined by the line segment but
* not on the ray from the segment's starting point and through its end
* point.
*
* @param x1
* the x coordinate of the starting point of the line segment.
* @param y1
* the y coordinate of the starting point of the line segment.
* @param x2
* the x coordinate of the end point of the line segment.
* @param y2
* the y coordinate of the end point of the line segment.
* @param px
* the x coordinate of the test point.
* @param py
* the p coordinate of the test point.
* @return the value that describes where the point is with respect to the
* line segment, given the orientation of the line segment.
*/
public static int relativeCCW(double x1, double y1, double x2, double y2, double px, double py) {
/*
* A = (x2-x1, y2-y1) P = (px-x1, py-y1)
*/
x2 -= x1;
y2 -= y1;
px -= x1;
py -= y1;
double t = px * y2 - py * x2; // PxA
if (t == 0.0) {
t = px * x2 + py * y2; // P*A
if (t > 0.0) {
px -= x2; // B-A
py -= y2;
t = px * x2 + py * y2; // (P-A)*A
if (t < 0.0) {
t = 0.0;
}
}
}
return t < 0.0 ? -1 : (t > 0.0 ? 1 : 0);
}
/**
* Tells where the point is with respect to this line segment, given the
* orientation of this line segment. If the ray found by extending the line
* segment from its starting point is rotated, this method tells whether the
* ray should rotate in a clockwise direction or a counter-clockwise
* direction to hit the point first. The return value is 0 if the point is
* on the line segment, it's 1 if the point is on the ray or if the ray
* should rotate in a counter-clockwise direction to get to the point, and
* it's -1 if the ray should rotate in a clockwise direction to get to the
* point or if the point is on the line determined by the line segment but
* not on the ray from the segment's starting point and through its end
* point.
*
* @param px
* the x coordinate of the test point.
* @param py
* the p coordinate of the test point.
* @return the value that describes where the point is with respect to this
* line segment, given the orientation of this line segment.
*/
public int relativeCCW(double px, double py) {
return relativeCCW(getX1(), getY1(), getX2(), getY2(), px, py);
}
/**
* Tells where the point is with respect to this line segment, given the
* orientation of this line segment. If the ray found by extending the line
* segment from its starting point is rotated, this method tells whether the
* ray should rotate in a clockwise direction or a counter-clockwise
* direction to hit the point first. The return value is 0 if the point is
* on the line segment, it's 1 if the point is on the ray or if the ray
* should rotate in a counter-clockwise direction to get to the point, and
* it's -1 if the ray should rotate in a clockwise direction to get to the
* point or if the point is on the line determined by the line segment but
* not on the ray from the segment's starting point and through its end
* point.
*
* @param p
* the test point.
* @return the value that describes where the point is with respect to this
* line segment, given the orientation of this line segment.
*/
public int relativeCCW(Point2D p) {
return relativeCCW(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
}
/**
* Tells whether the two line segments cross.
*
* @param x1
* the x coordinate of the starting point of the first segment.
* @param y1
* the y coordinate of the starting point of the first segment.
* @param x2
* the x coordinate of the end point of the first segment.
* @param y2
* the y coordinate of the end point of the first segment.
* @param x3
* the x coordinate of the starting point of the second segment.
* @param y3
* the y coordinate of the starting point of the second segment.
* @param x4
* the x coordinate of the end point of the second segment.
* @param y4
* the y coordinate of the end point of the second segment.
* @return true, if the two line segments cross.
*/
public static boolean linesIntersect(double x1, double y1, double x2, double y2, double x3,
double y3, double x4, double y4) {
/*
* A = (x2-x1, y2-y1) B = (x3-x1, y3-y1) C = (x4-x1, y4-y1) D = (x4-x3,
* y4-y3) = C-B E = (x1-x3, y1-y3) = -B F = (x2-x3, y2-y3) = A-B Result
* is ((AxB) (AxC) <=0) and ((DxE) (DxF) <= 0) DxE = (C-B)x(-B) =
* BxB-CxB = BxC DxF = (C-B)x(A-B) = CxA-CxB-BxA+BxB = AxB+BxC-AxC
*/
x2 -= x1; // A
y2 -= y1;
x3 -= x1; // B
y3 -= y1;
x4 -= x1; // C
y4 -= y1;
double AvB = x2 * y3 - x3 * y2;
double AvC = x2 * y4 - x4 * y2;
// Online
if (AvB == 0.0 && AvC == 0.0) {
if (x2 != 0.0) {
return (x4 * x3 <= 0.0)
|| ((x3 * x2 >= 0.0) && (x2 > 0.0 ? x3 <= x2 || x4 <= x2 : x3 >= x2
|| x4 >= x2));
}
if (y2 != 0.0) {
return (y4 * y3 <= 0.0)
|| ((y3 * y2 >= 0.0) && (y2 > 0.0 ? y3 <= y2 || y4 <= y2 : y3 >= y2
|| y4 >= y2));
}
return false;
}
double BvC = x3 * y4 - x4 * y3;
return (AvB * AvC <= 0.0) && (BvC * (AvB + BvC - AvC) <= 0.0);
}
/**
* Tells whether the specified line segments crosses this line segment.
*
* @param x1
* the x coordinate of the starting point of the test segment.
* @param y1
* the y coordinate of the starting point of the test segment.
* @param x2
* the x coordinate of the end point of the test segment.
* @param y2
* the y coordinate of the end point of the test segment.
* @return true, if the specified line segments crosses this line segment.
*/
public boolean intersectsLine(double x1, double y1, double x2, double y2) {
return linesIntersect(x1, y1, x2, y2, getX1(), getY1(), getX2(), getY2());
}
/**
* Tells whether the specified line segments crosses this line segment.
*
* @param l
* the test segment.
* @return true, if the specified line segments crosses this line segment.
* @throws NullPointerException
* if l is null.
*/
public boolean intersectsLine(Line2D l) {
return linesIntersect(l.getX1(), l.getY1(), l.getX2(), l.getY2(), getX1(), getY1(),
getX2(), getY2());
}
/**
* Gives the square of the distance between the point and the line segment.
*
* @param x1
* the x coordinate of the starting point of the line segment.
* @param y1
* the y coordinate of the starting point of the line segment.
* @param x2
* the x coordinate of the end point of the line segment.
* @param y2
* the y coordinate of the end point of the line segment.
* @param px
* the x coordinate of the test point.
* @param py
* the y coordinate of the test point.
* @return the the square of the distance between the point and the line
* segment.
*/
public static double ptSegDistSq(double x1, double y1, double x2, double y2, double px,
double py) {
/*
* A = (x2 - x1, y2 - y1) P = (px - x1, py - y1)
*/
x2 -= x1; // A = (x2, y2)
y2 -= y1;
px -= x1; // P = (px, py)
py -= y1;
double dist;
if (px * x2 + py * y2 <= 0.0) { // P*A
dist = px * px + py * py;
} else {
px = x2 - px; // P = A - P = (x2 - px, y2 - py)
py = y2 - py;
if (px * x2 + py * y2 <= 0.0) { // P*A
dist = px * px + py * py;
} else {
dist = px * y2 - py * x2;
dist = dist * dist / (x2 * x2 + y2 * y2); // pxA/|A|
}
}
if (dist < 0) {
dist = 0;
}
return dist;
}
/**
* Gives the distance between the point and the line segment.
*
* @param x1
* the x coordinate of the starting point of the line segment.
* @param y1
* the y coordinate of the starting point of the line segment.
* @param x2
* the x coordinate of the end point of the line segment.
* @param y2
* the y coordinate of the end point of the line segment.
* @param px
* the x coordinate of the test point.
* @param py
* the y coordinate of the test point.
* @return the the distance between the point and the line segment.
*/
public static double ptSegDist(double x1, double y1, double x2, double y2, double px, double py) {
return Math.sqrt(ptSegDistSq(x1, y1, x2, y2, px, py));
}
/**
* Gives the square of the distance between the point and this line segment.
*
* @param px
* the x coordinate of the test point.
* @param py
* the y coordinate of the test point.
* @return the the square of the distance between the point and this line
* segment.
*/
public double ptSegDistSq(double px, double py) {
return ptSegDistSq(getX1(), getY1(), getX2(), getY2(), px, py);
}
/**
* Gives the square of the distance between the point and this line segment.
*
* @param p
* the test point.
* @return the square of the distance between the point and this line
* segment.
*/
public double ptSegDistSq(Point2D p) {
return ptSegDistSq(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
}
/**
* Gives the distance between the point and this line segment.
*
* @param px
* the x coordinate of the test point.
* @param py
* the y coordinate of the test point.
* @return the distance between the point and this line segment.
*/
public double ptSegDist(double px, double py) {
return ptSegDist(getX1(), getY1(), getX2(), getY2(), px, py);
}
/**
* Gives the distance between the point and this line segment.
*
* @param p
* the test point.
* @return the distance between the point and this line segment.
*/
public double ptSegDist(Point2D p) {
return ptSegDist(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
}
/**
* Gives the square of the distance between the point and the line.
*
* @param x1
* the x coordinate of the starting point of the line segment.
* @param y1
* the y coordinate of the starting point of the line segment.
* @param x2
* the x coordinate of the end point of the line segment.
* @param y2
* the y coordinate of the end point of the line segment.
* @param px
* the x coordinate of the test point.
* @param py
* the y coordinate of the test point.
* @return the square of the distance between the point and the line.
*/
public static double ptLineDistSq(double x1, double y1, double x2, double y2, double px,
double py) {
x2 -= x1;
y2 -= y1;
px -= x1;
py -= y1;
double s = px * y2 - py * x2;
return s * s / (x2 * x2 + y2 * y2);
}
/**
* Gives the square of the distance between the point and the line.
*
* @param x1
* the x coordinate of the starting point of the line segment.
* @param y1
* the y coordinate of the starting point of the line segment.
* @param x2
* the x coordinate of the end point of the line segment.
* @param y2
* the y coordinate of the end point of the line segment.
* @param px
* the x coordinate of the test point.
* @param py
* the y coordinate of the test point.
* @return the square of the distance between the point and the line.
*/
public static double ptLineDist(double x1, double y1, double x2, double y2, double px, double py) {
return Math.sqrt(ptLineDistSq(x1, y1, x2, y2, px, py));
}
/**
* Gives the square of the distance between the point and the line
* determined by this Line2D.
*
* @param px
* the x coordinate of the test point.
* @param py
* the y coordinate of the test point.
* @return the square of the distance between the point and the line
* determined by this Line2D.
*/
public double ptLineDistSq(double px, double py) {
return ptLineDistSq(getX1(), getY1(), getX2(), getY2(), px, py);
}
/**
* Gives the square of the distance between the point and the line
* determined by this Line2D.
*
* @param p
* the test point.
* @return the square of the distance between the point and the line
* determined by this Line2D.
*/
public double ptLineDistSq(Point2D p) {
return ptLineDistSq(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
}
/**
* Gives the distance between the point and the line determined by this
* Line2D.
*
* @param px
* the x coordinate of the test point.
* @param py
* the y coordinate of the test point.
* @return the distance between the point and the line determined by this
* Line2D.
*/
public double ptLineDist(double px, double py) {
return ptLineDist(getX1(), getY1(), getX2(), getY2(), px, py);
}
/**
* Gives the distance between the point and the line determined by this
* Line2D.
*
* @param p
* the test point.
* @return the distance between the point and the line determined by this
* Line2D.
*/
public double ptLineDist(Point2D p) {
return ptLineDist(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
}
public boolean contains(double px, double py) {
return false;
}
public boolean contains(Point2D p) {
return false;
}
public boolean contains(Rectangle2D r) {
return false;
}
public boolean contains(double rx, double ry, double rw, double rh) {
return false;
}
public boolean intersects(double rx, double ry, double rw, double rh) {
return intersects(new Rectangle2D.Double(rx, ry, rw, rh));
}
public boolean intersects(Rectangle2D r) {
return r.intersectsLine(getX1(), getY1(), getX2(), getY2());
}
public PathIterator getPathIterator(AffineTransform at) {
return new Iterator(this, at);
}
public PathIterator getPathIterator(AffineTransform at, double flatness) {
return new Iterator(this, at);
}
@Override
public Object clone() {
try {
return super.clone();
} catch (CloneNotSupportedException e) {
throw new InternalError();
}
}
}
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