/* * 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(); } } }