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/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2014, by Object Refinery Limited and Contributors. * * Project Info: http://www.jfree.org/jfreechart/index.html * * This library is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This library is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public * License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, * USA. * * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. * Other names may be trademarks of their respective owners.] * * --------------- * ShapeUtils.java * --------------- * (C)opyright 2003-2014, by Object Refinery Limited and Contributors. * * Original Author: David Gilbert (for Object Refinery Limited); * Contributor(s): -; * * Changes * ------- * 13-Aug-2003 : Version 1 (DG); * 16-Mar-2004 : Moved rotateShape() from RefineryUtilities.java to here (DG); * 13-May-2004 : Added new shape creation methods (DG); * 30-Sep-2004 : Added createLineRegion() method (DG); * Moved drawRotatedShape() method from RefineryUtilities class * to this class (DG); * 04-Oct-2004 : Renamed ShapeUtils --> ShapeUtilities (DG); * 26-Oct-2004 : Added a method to test the equality of two Line2D * instances (DG); * 10-Nov-2004 : Added new translateShape() and equal(Ellipse2D, Ellipse2D) * methods (DG); * 11-Nov-2004 : Renamed translateShape() --> createTranslatedShape() (DG); * 07-Jan-2005 : Minor Javadoc fix (DG); * 11-Jan-2005 : Removed deprecated code in preparation for 1.0.0 release (DG); * 21-Jan-2005 : Modified return type of RectangleAnchor.coordinates() * method (DG); * 22-Feb-2005 : Added equality tests for Arc2D and GeneralPath (DG); * 16-Mar-2005 : Fixed bug where equal(Shape, Shape) fails for two Polygon * instances (DG); * 01-Jun-2008 : Fixed bug in equal(GeneralPath, GeneralPath) method (DG); * 16-Jun-2012 : Moved from JCommon to JFreeChart (DG); * */ package org.jfree.chart.util; import java.awt.Graphics2D; import java.awt.Polygon; import java.awt.Shape; import java.awt.geom.AffineTransform; import java.awt.geom.Arc2D; import java.awt.geom.Ellipse2D; import java.awt.geom.GeneralPath; import java.awt.geom.Line2D; import java.awt.geom.PathIterator; import java.awt.geom.Point2D; import java.awt.geom.Rectangle2D; import java.util.Arrays; import org.jfree.chart.ui.RectangleAnchor; /** * Utility methods for {@link Shape} objects. */ public class ShapeUtils { /** * Prevents instantiation. */ private ShapeUtils() { } /** * Returns a clone of the specified shape, or <code>null</code>. At the * current time, this method supports cloning for instances of * <code>Line2D</code>, <code>RectangularShape</code>, <code>Area</code> * and <code>GeneralPath</code>. * <p> * <code>RectangularShape</code> includes <code>Arc2D</code>, * <code>Ellipse2D</code>, <code>Rectangle2D</code>, * <code>RoundRectangle2D</code>. * * @param shape the shape to clone (<code>null</code> permitted, * returns <code>null</code>). * * @return A clone or <code>null</code>. */ public static Shape clone(Shape shape) { if (shape instanceof Cloneable) { try { return ObjectUtils.clone(shape); } catch (CloneNotSupportedException cnse) { //this shouldn't be thrown if object is cloneable } } return null; } /** * Tests two shapes for equality. If both shapes are <code>null</code>, * this method will return <code>true</code>. * <p> * In the current implementation, the following shapes are supported: * <code>Ellipse2D</code>, <code>Line2D</code> and <code>Rectangle2D</code> * (implicit). * * @param s1 the first shape (<code>null</code> permitted). * @param s2 the second shape (<code>null</code> permitted). * * @return A boolean. */ public static boolean equal(Shape s1, Shape s2) { if (s1 instanceof Line2D && s2 instanceof Line2D) { return equal((Line2D) s1, (Line2D) s2); } else if (s1 instanceof Ellipse2D && s2 instanceof Ellipse2D) { return equal((Ellipse2D) s1, (Ellipse2D) s2); } else if (s1 instanceof Arc2D && s2 instanceof Arc2D) { return equal((Arc2D) s1, (Arc2D) s2); } else if (s1 instanceof Polygon && s2 instanceof Polygon) { return equal((Polygon) s1, (Polygon) s2); } else if (s1 instanceof GeneralPath && s2 instanceof GeneralPath) { return equal((GeneralPath) s1, (GeneralPath) s2); } else { // this will handle Rectangle2D... return ObjectUtils.equal(s1, s2); } } /** * Compares two lines are returns <code>true</code> if they are equal or * both <code>null</code>. * * @param l1 the first line (<code>null</code> permitted). * @param l2 the second line (<code>null</code> permitted). * * @return A boolean. */ public static boolean equal(Line2D l1, Line2D l2) { if (l1 == null) { return (l2 == null); } if (l2 == null) { return false; } if (!l1.getP1().equals(l2.getP1())) { return false; } if (!l1.getP2().equals(l2.getP2())) { return false; } return true; } /** * Compares two ellipses and returns <code>true</code> if they are equal or * both <code>null</code>. * * @param e1 the first ellipse (<code>null</code> permitted). * @param e2 the second ellipse (<code>null</code> permitted). * * @return A boolean. */ public static boolean equal(Ellipse2D e1, Ellipse2D e2) { if (e1 == null) { return (e2 == null); } if (e2 == null) { return false; } if (!e1.getFrame().equals(e2.getFrame())) { return false; } return true; } /** * Compares two arcs and returns <code>true</code> if they are equal or * both <code>null</code>. * * @param a1 the first arc (<code>null</code> permitted). * @param a2 the second arc (<code>null</code> permitted). * * @return A boolean. */ public static boolean equal(Arc2D a1, Arc2D a2) { if (a1 == null) { return (a2 == null); } if (a2 == null) { return false; } if (!a1.getFrame().equals(a2.getFrame())) { return false; } if (a1.getAngleStart() != a2.getAngleStart()) { return false; } if (a1.getAngleExtent() != a2.getAngleExtent()) { return false; } if (a1.getArcType() != a2.getArcType()) { return false; } return true; } /** * Tests two polygons for equality. If both are <code>null</code> this * method returns <code>true</code>. * * @param p1 polygon 1 (<code>null</code> permitted). * @param p2 polygon 2 (<code>null</code> permitted). * * @return A boolean. */ public static boolean equal(Polygon p1, Polygon p2) { if (p1 == null) { return (p2 == null); } if (p2 == null) { return false; } if (p1.npoints != p2.npoints) { return false; } if (!Arrays.equals(p1.xpoints, p2.xpoints)) { return false; } if (!Arrays.equals(p1.ypoints, p2.ypoints)) { return false; } return true; } /** * Tests two polygons for equality. If both are <code>null</code> this * method returns <code>true</code>. * * @param p1 path 1 (<code>null</code> permitted). * @param p2 path 2 (<code>null</code> permitted). * * @return A boolean. */ public static boolean equal(GeneralPath p1, GeneralPath p2) { if (p1 == null) { return (p2 == null); } if (p2 == null) { return false; } if (p1.getWindingRule() != p2.getWindingRule()) { return false; } PathIterator iterator1 = p1.getPathIterator(null); PathIterator iterator2 = p2.getPathIterator(null); double[] d1 = new double[6]; double[] d2 = new double[6]; boolean done = iterator1.isDone() && iterator2.isDone(); while (!done) { if (iterator1.isDone() != iterator2.isDone()) { return false; } int seg1 = iterator1.currentSegment(d1); int seg2 = iterator2.currentSegment(d2); if (seg1 != seg2) { return false; } if (!Arrays.equals(d1, d2)) { return false; } iterator1.next(); iterator2.next(); done = iterator1.isDone() && iterator2.isDone(); } return true; } /** * Creates and returns a translated shape. * * @param shape the shape (<code>null</code> not permitted). * @param transX the x translation (in Java2D space). * @param transY the y translation (in Java2D space). * * @return The translated shape. */ public static Shape createTranslatedShape(Shape shape, double transX, double transY) { if (shape == null) { throw new IllegalArgumentException("Null 'shape' argument."); } AffineTransform transform = AffineTransform.getTranslateInstance(transX, transY); return transform.createTransformedShape(shape); } /** * Translates a shape to a new location such that the anchor point * (relative to the rectangular bounds of the shape) aligns with the * specified (x, y) coordinate in Java2D space. * * @param shape the shape (<code>null</code> not permitted). * @param anchor the anchor (<code>null</code> not permitted). * @param locationX the x-coordinate (in Java2D space). * @param locationY the y-coordinate (in Java2D space). * * @return A new and translated shape. */ public static Shape createTranslatedShape(Shape shape, RectangleAnchor anchor, double locationX, double locationY) { ParamChecks.nullNotPermitted(shape, "shape"); ParamChecks.nullNotPermitted(anchor, "anchor"); Point2D anchorPoint = RectangleAnchor.coordinates(shape.getBounds2D(), anchor); AffineTransform transform = AffineTransform.getTranslateInstance(locationX - anchorPoint.getX(), locationY - anchorPoint.getY()); return transform.createTransformedShape(shape); } /** * Rotates a shape about the specified coordinates. * * @param base the shape (<code>null</code> permitted, returns * <code>null</code>). * @param angle the angle (in radians). * @param x the x coordinate for the rotation point (in Java2D space). * @param y the y coordinate for the rotation point (in Java2D space). * * @return the rotated shape. */ public static Shape rotateShape(Shape base, double angle, float x, float y) { if (base == null) { return null; } AffineTransform rotate = AffineTransform.getRotateInstance(angle, x, y); Shape result = rotate.createTransformedShape(base); return result; } /** * Draws a shape with the specified rotation about <code>(x, y)</code>. * * @param g2 the graphics device (<code>null</code> not permitted). * @param shape the shape (<code>null</code> not permitted). * @param angle the angle (in radians). * @param x the x coordinate for the rotation point. * @param y the y coordinate for the rotation point. */ public static void drawRotatedShape(Graphics2D g2, final Shape shape, double angle, float x, final float y) { AffineTransform saved = g2.getTransform(); AffineTransform rotate = AffineTransform.getRotateInstance(angle, x, y); g2.transform(rotate); g2.draw(shape); g2.setTransform(saved); } /** A useful constant used internally. */ private static final float SQRT2 = (float) Math.pow(2.0, 0.5); /** * Creates a diagonal cross shape. * * @param l the length of each 'arm'. * @param t the thickness. * * @return A diagonal cross shape. */ public static Shape createDiagonalCross(float l, float t) { GeneralPath p0 = new GeneralPath(); p0.moveTo(-l - t, -l + t); p0.lineTo(-l + t, -l - t); p0.lineTo(0.0f, -t * SQRT2); p0.lineTo(l - t, -l - t); p0.lineTo(l + t, -l + t); p0.lineTo(t * SQRT2, 0.0f); p0.lineTo(l + t, l - t); p0.lineTo(l - t, l + t); p0.lineTo(0.0f, t * SQRT2); p0.lineTo(-l + t, l + t); p0.lineTo(-l - t, l - t); p0.lineTo(-t * SQRT2, 0.0f); p0.closePath(); return p0; } /** * Creates a diagonal cross shape. * * @param l the length of each 'arm'. * @param t the thickness. * * @return A diagonal cross shape. */ public static Shape createRegularCross(float l, float t) { GeneralPath p0 = new GeneralPath(); p0.moveTo(-l, t); p0.lineTo(-t, t); p0.lineTo(-t, l); p0.lineTo(t, l); p0.lineTo(t, t); p0.lineTo(l, t); p0.lineTo(l, -t); p0.lineTo(t, -t); p0.lineTo(t, -l); p0.lineTo(-t, -l); p0.lineTo(-t, -t); p0.lineTo(-l, -t); p0.closePath(); return p0; } /** * Creates a diamond shape. * * @param s the size factor (equal to half the height of the diamond). * * @return A diamond shape. */ public static Shape createDiamond(float s) { GeneralPath p0 = new GeneralPath(); p0.moveTo(0.0f, -s); p0.lineTo(s, 0.0f); p0.lineTo(0.0f, s); p0.lineTo(-s, 0.0f); p0.closePath(); return p0; } /** * Creates a triangle shape that points upwards. * * @param s the size factor (equal to half the height of the triangle). * * @return A triangle shape. */ public static Shape createUpTriangle(float s) { GeneralPath p0 = new GeneralPath(); p0.moveTo(0.0f, -s); p0.lineTo(s, s); p0.lineTo(-s, s); p0.closePath(); return p0; } /** * Creates a triangle shape that points downwards. * * @param s the size factor (equal to half the height of the triangle). * * @return A triangle shape. */ public static Shape createDownTriangle(float s) { GeneralPath p0 = new GeneralPath(); p0.moveTo(0.0f, s); p0.lineTo(s, -s); p0.lineTo(-s, -s); p0.closePath(); return p0; } /** * Creates a region surrounding a line segment by 'widening' the line * segment. A typical use for this method is the creation of a * 'clickable' region for a line that is displayed on-screen. * * @param line the line (<code>null</code> not permitted). * @param width the width of the region. * * @return A region that surrounds the line. */ public static Shape createLineRegion(Line2D line, float width) { GeneralPath result = new GeneralPath(); float x1 = (float) line.getX1(); float x2 = (float) line.getX2(); float y1 = (float) line.getY1(); float y2 = (float) line.getY2(); if ((x2 - x1) != 0.0) { double theta = Math.atan((y2 - y1) / (x2 - x1)); float dx = (float) Math.sin(theta) * width; float dy = (float) Math.cos(theta) * width; result.moveTo(x1 - dx, y1 + dy); result.lineTo(x1 + dx, y1 - dy); result.lineTo(x2 + dx, y2 - dy); result.lineTo(x2 - dx, y2 + dy); result.closePath(); } else { // special case, vertical line result.moveTo(x1 - width / 2.0f, y1); result.lineTo(x1 + width / 2.0f, y1); result.lineTo(x2 + width / 2.0f, y2); result.lineTo(x2 - width / 2.0f, y2); result.closePath(); } return result; } /** * Returns a point based on (x, y) but constrained to be within the bounds * of a given rectangle. * * @param x the x-coordinate. * @param y the y-coordinate. * @param area the constraining rectangle (<code>null</code> not * permitted). * * @return A point within the rectangle. * * @throws NullPointerException if <code>area</code> is <code>null</code>. */ public static Point2D getPointInRectangle(double x, double y, Rectangle2D area) { x = Math.max(area.getMinX(), Math.min(x, area.getMaxX())); y = Math.max(area.getMinY(), Math.min(y, area.getMaxY())); return new Point2D.Double(x, y); } /** * Checks, whether the given rectangle1 fully contains rectangle 2 * (even if rectangle 2 has a height or width of zero!). * * @param rect1 the first rectangle. * @param rect2 the second rectangle. * * @return A boolean. */ public static boolean contains(Rectangle2D rect1, Rectangle2D rect2) { double x0 = rect1.getX(); double y0 = rect1.getY(); double x = rect2.getX(); double y = rect2.getY(); double w = rect2.getWidth(); double h = rect2.getHeight(); return ((x >= x0) && (y >= y0) && ((x + w) <= (x0 + rect1.getWidth())) && ((y + h) <= (y0 + rect1.getHeight()))); } /** * Checks, whether the given rectangle1 fully contains rectangle 2 * (even if rectangle 2 has a height or width of zero!). * * @param rect1 the first rectangle. * @param rect2 the second rectangle. * * @return A boolean. */ public static boolean intersects(Rectangle2D rect1, Rectangle2D rect2) { double x0 = rect1.getX(); double y0 = rect1.getY(); double x = rect2.getX(); double width = rect2.getWidth(); double y = rect2.getY(); double height = rect2.getHeight(); return (x + width >= x0 && y + height >= y0 && x <= x0 + rect1.getWidth() && y <= y0 + rect1.getHeight()); } }