mirror of git://gcc.gnu.org/git/gcc.git
903 lines
27 KiB
Java
903 lines
27 KiB
Java
/* BasicStroke.java --
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Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
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This file is part of GNU Classpath.
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GNU Classpath is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GNU Classpath is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Classpath; see the file COPYING. If not, write to the
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301 USA.
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Linking this library statically or dynamically with other modules is
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making a combined work based on this library. Thus, the terms and
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conditions of the GNU General Public License cover the whole
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combination.
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As a special exception, the copyright holders of this library give you
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permission to link this library with independent modules to produce an
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executable, regardless of the license terms of these independent
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modules, and to copy and distribute the resulting executable under
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terms of your choice, provided that you also meet, for each linked
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independent module, the terms and conditions of the license of that
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module. An independent module is a module which is not derived from
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or based on this library. If you modify this library, you may extend
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this exception to your version of the library, but you are not
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obligated to do so. If you do not wish to do so, delete this
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exception statement from your version. */
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package java.awt;
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import gnu.java.awt.java2d.CubicSegment;
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import gnu.java.awt.java2d.LineSegment;
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import gnu.java.awt.java2d.QuadSegment;
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import gnu.java.awt.java2d.Segment;
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import java.awt.geom.FlatteningPathIterator;
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import java.awt.geom.GeneralPath;
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import java.awt.geom.PathIterator;
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import java.awt.geom.Point2D;
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import java.util.Arrays;
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/**
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* A general purpose {@link Stroke} implementation that can represent a wide
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* variety of line styles for use with subclasses of {@link Graphics2D}.
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* <p>
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* The line cap and join styles can be set using the options illustrated
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* here:
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* <p>
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* <img src="doc-files/capjoin.png" width="350" height="180"
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* alt="Illustration of line cap and join styles" />
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* <p>
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* A dash array can be used to specify lines with alternating opaque and
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* transparent sections.
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*/
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public class BasicStroke implements Stroke
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{
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/**
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* Indicates a mitered line join style. See the class overview for an
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* illustration.
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*/
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public static final int JOIN_MITER = 0;
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/**
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* Indicates a rounded line join style. See the class overview for an
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* illustration.
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*/
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public static final int JOIN_ROUND = 1;
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/**
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* Indicates a bevelled line join style. See the class overview for an
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* illustration.
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*/
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public static final int JOIN_BEVEL = 2;
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/**
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* Indicates a flat line cap style. See the class overview for an
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* illustration.
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*/
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public static final int CAP_BUTT = 0;
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/**
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* Indicates a rounded line cap style. See the class overview for an
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* illustration.
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*/
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public static final int CAP_ROUND = 1;
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/**
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* Indicates a square line cap style. See the class overview for an
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* illustration.
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*/
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public static final int CAP_SQUARE = 2;
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/** The stroke width. */
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private final float width;
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/** The line cap style. */
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private final int cap;
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/** The line join style. */
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private final int join;
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/** The miter limit. */
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private final float limit;
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/** The dash array. */
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private final float[] dash;
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/** The dash phase. */
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private final float phase;
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// The inner and outer paths of the stroke
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private Segment start, end;
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/**
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* Creates a new <code>BasicStroke</code> instance with the given attributes.
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*
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* @param width the line width (>= 0.0f).
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* @param cap the line cap style (one of {@link #CAP_BUTT},
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* {@link #CAP_ROUND} or {@link #CAP_SQUARE}).
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* @param join the line join style (one of {@link #JOIN_ROUND},
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* {@link #JOIN_BEVEL}, or {@link #JOIN_MITER}).
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* @param miterlimit the limit to trim the miter join. The miterlimit must be
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* greater than or equal to 1.0f.
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* @param dash The array representing the dashing pattern. There must be at
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* least one non-zero entry.
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* @param dashPhase is negative and dash is not null.
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*
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* @throws IllegalArgumentException If one input parameter doesn't meet
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* its needs.
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*/
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public BasicStroke(float width, int cap, int join, float miterlimit,
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float[] dash, float dashPhase)
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{
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if (width < 0.0f )
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throw new IllegalArgumentException("width " + width + " < 0");
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else if (cap < CAP_BUTT || cap > CAP_SQUARE)
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throw new IllegalArgumentException("cap " + cap + " out of range ["
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+ CAP_BUTT + ".." + CAP_SQUARE + "]");
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else if (miterlimit < 1.0f && join == JOIN_MITER)
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throw new IllegalArgumentException("miterlimit " + miterlimit
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+ " < 1.0f while join == JOIN_MITER");
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else if (join < JOIN_MITER || join > JOIN_BEVEL)
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throw new IllegalArgumentException("join " + join + " out of range ["
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+ JOIN_MITER + ".." + JOIN_BEVEL
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+ "]");
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else if (dashPhase < 0.0f && dash != null)
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throw new IllegalArgumentException("dashPhase " + dashPhase
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+ " < 0.0f while dash != null");
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else if (dash != null)
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if (dash.length == 0)
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throw new IllegalArgumentException("dash.length is 0");
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else
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{
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boolean allZero = true;
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for ( int i = 0; i < dash.length; ++i)
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{
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if (dash[i] != 0.0f)
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{
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allZero = false;
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break;
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}
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}
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if (allZero)
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throw new IllegalArgumentException("all dashes are 0.0f");
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}
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this.width = width;
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this.cap = cap;
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this.join = join;
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limit = miterlimit;
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this.dash = dash == null ? null : (float[]) dash.clone();
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phase = dashPhase;
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}
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/**
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* Creates a new <code>BasicStroke</code> instance with the given attributes.
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*
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* @param width the line width (>= 0.0f).
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* @param cap the line cap style (one of {@link #CAP_BUTT},
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* {@link #CAP_ROUND} or {@link #CAP_SQUARE}).
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* @param join the line join style (one of {@link #JOIN_ROUND},
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* {@link #JOIN_BEVEL}, or {@link #JOIN_MITER}).
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* @param miterlimit the limit to trim the miter join. The miterlimit must be
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* greater than or equal to 1.0f.
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*
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* @throws IllegalArgumentException If one input parameter doesn't meet
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* its needs.
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*/
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public BasicStroke(float width, int cap, int join, float miterlimit)
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{
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this(width, cap, join, miterlimit, null, 0);
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}
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/**
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* Creates a new <code>BasicStroke</code> instance with the given attributes.
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* The miter limit defaults to <code>10.0</code>.
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*
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* @param width the line width (>= 0.0f).
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* @param cap the line cap style (one of {@link #CAP_BUTT},
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* {@link #CAP_ROUND} or {@link #CAP_SQUARE}).
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* @param join the line join style (one of {@link #JOIN_ROUND},
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* {@link #JOIN_BEVEL}, or {@link #JOIN_MITER}).
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*
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* @throws IllegalArgumentException If one input parameter doesn't meet
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* its needs.
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*/
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public BasicStroke(float width, int cap, int join)
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{
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this(width, cap, join, 10, null, 0);
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}
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/**
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* Creates a new <code>BasicStroke</code> instance with the given line
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* width. The default values are:
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* <ul>
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* <li>line cap style: {@link #CAP_SQUARE};</li>
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* <li>line join style: {@link #JOIN_MITER};</li>
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* <li>miter limit: <code>10.0f</code>.
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* </ul>
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*
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* @param width the line width (>= 0.0f).
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*
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* @throws IllegalArgumentException If <code>width</code> is negative.
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*/
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public BasicStroke(float width)
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{
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this(width, CAP_SQUARE, JOIN_MITER, 10, null, 0);
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}
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/**
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* Creates a new <code>BasicStroke</code> instance. The default values are:
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* <ul>
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* <li>line width: <code>1.0f</code>;</li>
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* <li>line cap style: {@link #CAP_SQUARE};</li>
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* <li>line join style: {@link #JOIN_MITER};</li>
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* <li>miter limit: <code>10.0f</code>.
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* </ul>
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*/
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public BasicStroke()
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{
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this(1, CAP_SQUARE, JOIN_MITER, 10, null, 0);
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}
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/**
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* Creates a shape representing the stroked outline of the given shape.
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* THIS METHOD IS NOT YET IMPLEMENTED.
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*
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* @param s the shape.
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*/
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public Shape createStrokedShape(Shape s)
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{
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PathIterator pi = s.getPathIterator(null);
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if( dash == null )
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return solidStroke( pi );
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return dashedStroke( pi );
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}
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/**
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* Returns the line width.
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*
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* @return The line width.
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*/
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public float getLineWidth()
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{
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return width;
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}
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/**
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* Returns a code indicating the line cap style (one of {@link #CAP_BUTT},
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* {@link #CAP_ROUND}, {@link #CAP_SQUARE}).
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*
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* @return A code indicating the line cap style.
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*/
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public int getEndCap()
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{
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return cap;
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}
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/**
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* Returns a code indicating the line join style (one of {@link #JOIN_BEVEL},
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* {@link #JOIN_MITER} or {@link #JOIN_ROUND}).
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*
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* @return A code indicating the line join style.
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*/
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public int getLineJoin()
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{
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return join;
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}
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/**
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* Returns the miter limit.
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*
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* @return The miter limit.
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*/
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public float getMiterLimit()
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{
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return limit;
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}
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/**
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* Returns the dash array, which defines the length of alternate opaque and
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* transparent sections in lines drawn with this stroke. If
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* <code>null</code>, a continuous line will be drawn.
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*
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* @return The dash array (possibly <code>null</code>).
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*/
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public float[] getDashArray()
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{
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return dash;
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}
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/**
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* Returns the dash phase for the stroke. This is the offset from the start
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* of a path at which the pattern defined by {@link #getDashArray()} is
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* rendered.
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*
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* @return The dash phase.
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*/
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public float getDashPhase()
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{
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return phase;
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}
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/**
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* Returns the hash code for this object. The hash is calculated by
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* xoring the hash, cap, join, limit, dash array and phase values
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* (converted to <code>int</code> first with
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* <code>Float.floatToIntBits()</code> if the value is a
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* <code>float</code>).
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*
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* @return The hash code.
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*/
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public int hashCode()
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{
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int hash = Float.floatToIntBits(width);
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hash ^= cap;
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hash ^= join;
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hash ^= Float.floatToIntBits(limit);
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if (dash != null)
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for (int i = 0; i < dash.length; i++)
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hash ^= Float.floatToIntBits(dash[i]);
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hash ^= Float.floatToIntBits(phase);
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return hash;
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}
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/**
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* Compares this <code>BasicStroke</code> for equality with an arbitrary
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* object. This method returns <code>true</code> if and only if:
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* <ul>
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* <li><code>o</code> is an instanceof <code>BasicStroke</code>;</li>
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* <li>this object has the same width, line cap style, line join style,
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* miter limit, dash array and dash phase as <code>o</code>.</li>
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* </ul>
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*
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* @param o the object (<code>null</code> permitted).
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*
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* @return <code>true</code> if this stroke is equal to <code>o</code> and
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* <code>false</code> otherwise.
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*/
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public boolean equals(Object o)
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{
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if (! (o instanceof BasicStroke))
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return false;
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BasicStroke s = (BasicStroke) o;
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return width == s.width && cap == s.cap && join == s.join
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&& limit == s.limit && Arrays.equals(dash, s.dash) && phase == s.phase;
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}
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private Shape solidStroke(PathIterator pi)
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{
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double[] coords = new double[6];
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double x, y, x0, y0;
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boolean pathOpen = false;
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GeneralPath output = new GeneralPath( );
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Segment[] p;
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x = x0 = y = y0 = 0;
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while( !pi.isDone() )
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{
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switch( pi.currentSegment(coords) )
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{
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case PathIterator.SEG_MOVETO:
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x0 = x = coords[0];
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y0 = y = coords[1];
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if( pathOpen )
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{
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capEnds();
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convertPath(output, start);
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start = end = null;
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pathOpen = false;
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}
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break;
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case PathIterator.SEG_LINETO:
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p = (new LineSegment(x, y, coords[0], coords[1])).
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getDisplacedSegments(width/2.0);
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if( !pathOpen )
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{
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start = p[0];
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end = p[1];
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pathOpen = true;
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}
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else
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addSegments(p);
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x = coords[0];
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y = coords[1];
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break;
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case PathIterator.SEG_QUADTO:
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p = (new QuadSegment(x, y, coords[0], coords[1], coords[2],
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coords[3])).getDisplacedSegments(width/2.0);
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if( !pathOpen )
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{
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start = p[0];
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end = p[1];
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pathOpen = true;
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}
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else
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addSegments(p);
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x = coords[2];
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y = coords[3];
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break;
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case PathIterator.SEG_CUBICTO:
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p = new CubicSegment(x, y, coords[0], coords[1],
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coords[2], coords[3],
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coords[4], coords[5]).getDisplacedSegments(width/2.0);
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if( !pathOpen )
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{
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start = p[0];
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end = p[1];
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pathOpen = true;
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}
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else
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addSegments(p);
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x = coords[4];
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y = coords[5];
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break;
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case PathIterator.SEG_CLOSE:
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if (x == x0 && y == y0)
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{
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joinSegments(new Segment[] { start.first, end.first });
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}
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else
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{
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p = (new LineSegment(x, y, x0, y0)).getDisplacedSegments(width / 2.0);
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addSegments(p);
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}
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convertPath(output, start);
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convertPath(output, end);
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start = end = null;
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pathOpen = false;
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output.setWindingRule(GeneralPath.WIND_EVEN_ODD);
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break;
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}
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pi.next();
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}
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if( pathOpen )
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{
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capEnds();
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convertPath(output, start);
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}
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return output;
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}
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private Shape dashedStroke(PathIterator pi)
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{
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// The choice of (flatnessSq == width / 3) is made to be consistent with
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// the flattening in CubicSegment.getDisplacedSegments
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FlatteningPathIterator flat = new FlatteningPathIterator(pi,
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Math.sqrt(width / 3));
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// Holds the endpoint of the current segment (or piece of a segment)
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double[] coords = new double[2];
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// Holds end of the last segment
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double x, y, x0, y0;
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x = x0 = y = y0 = 0;
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// Various useful flags
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boolean pathOpen = false;
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boolean dashOn = true;
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boolean offsetting = (phase != 0);
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// How far we are into the current dash
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double distance = 0;
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int dashIndex = 0;
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// And variables to hold the final output
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GeneralPath output = new GeneralPath();
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Segment[] p;
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// Iterate over the FlatteningPathIterator
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while (! flat.isDone())
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{
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switch (flat.currentSegment(coords))
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{
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case PathIterator.SEG_MOVETO:
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x0 = x = coords[0];
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y0 = y = coords[1];
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if (pathOpen)
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{
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capEnds();
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convertPath(output, start);
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start = end = null;
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pathOpen = false;
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}
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break;
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case PathIterator.SEG_LINETO:
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boolean segmentConsumed = false;
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while (! segmentConsumed)
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{
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// Find the total remaining length of this segment
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double segLength = Math.sqrt((x - coords[0]) * (x - coords[0])
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+ (y - coords[1])
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* (y - coords[1]));
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boolean spanBoundary = true;
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double[] segmentEnd = null;
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|
|
// The current segment fits entirely inside the current dash
|
|
if ((offsetting && distance + segLength <= phase)
|
|
|| distance + segLength <= dash[dashIndex])
|
|
{
|
|
spanBoundary = false;
|
|
}
|
|
|
|
// Otherwise, we need to split the segment in two, as this
|
|
// segment spans a dash boundry
|
|
else
|
|
{
|
|
segmentEnd = (double[]) coords.clone();
|
|
|
|
// Calculate the remaining distance in this dash,
|
|
// and coordinates of the dash boundary
|
|
double reqLength;
|
|
if (offsetting)
|
|
reqLength = phase - distance;
|
|
else
|
|
reqLength = dash[dashIndex] - distance;
|
|
|
|
coords[0] = x + ((coords[0] - x) * reqLength / segLength);
|
|
coords[1] = y + ((coords[1] - y) * reqLength / segLength);
|
|
}
|
|
|
|
if (offsetting || ! dashOn)
|
|
{
|
|
// Dash is off, or we are in offset - treat this as a
|
|
// moveTo
|
|
x0 = x = coords[0];
|
|
y0 = y = coords[1];
|
|
|
|
if (pathOpen)
|
|
{
|
|
capEnds();
|
|
convertPath(output, start);
|
|
start = end = null;
|
|
pathOpen = false;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// Dash is on - treat this as a lineTo
|
|
p = (new LineSegment(x, y, coords[0], coords[1])).getDisplacedSegments(width / 2.0);
|
|
|
|
if (! pathOpen)
|
|
{
|
|
start = p[0];
|
|
end = p[1];
|
|
pathOpen = true;
|
|
}
|
|
else
|
|
addSegments(p);
|
|
|
|
x = coords[0];
|
|
y = coords[1];
|
|
}
|
|
|
|
// Update variables depending on whether we spanned a
|
|
// dash boundary or not
|
|
if (! spanBoundary)
|
|
{
|
|
distance += segLength;
|
|
segmentConsumed = true;
|
|
}
|
|
else
|
|
{
|
|
if (offsetting)
|
|
offsetting = false;
|
|
dashOn = ! dashOn;
|
|
distance = 0;
|
|
coords = segmentEnd;
|
|
|
|
if (dashIndex + 1 == dash.length)
|
|
dashIndex = 0;
|
|
else
|
|
dashIndex++;
|
|
|
|
// Since the value of segmentConsumed is still false,
|
|
// the next run of the while loop will complete the segment
|
|
}
|
|
}
|
|
break;
|
|
|
|
// This is a flattened path, so we don't need to deal with curves
|
|
}
|
|
flat.next();
|
|
}
|
|
|
|
if (pathOpen)
|
|
{
|
|
capEnds();
|
|
convertPath(output, start);
|
|
}
|
|
return output;
|
|
}
|
|
|
|
/**
|
|
* Cap the ends of the path (joining the start and end list of segments)
|
|
*/
|
|
private void capEnds()
|
|
{
|
|
Segment returnPath = end.last;
|
|
|
|
end.reverseAll(); // reverse the path.
|
|
end = null;
|
|
capEnd(start, returnPath);
|
|
start.last = returnPath.last;
|
|
end = null;
|
|
|
|
capEnd(start, start);
|
|
}
|
|
|
|
/**
|
|
* Append the Segments in s to the GeneralPath p
|
|
*/
|
|
private void convertPath(GeneralPath p, Segment s)
|
|
{
|
|
Segment v = s;
|
|
p.moveTo((float)s.P1.getX(), (float)s.P1.getY());
|
|
|
|
do
|
|
{
|
|
if(v instanceof LineSegment)
|
|
p.lineTo((float)v.P2.getX(), (float)v.P2.getY());
|
|
else if(v instanceof QuadSegment)
|
|
p.quadTo((float)((QuadSegment)v).cp.getX(),
|
|
(float)((QuadSegment)v).cp.getY(),
|
|
(float)v.P2.getX(),
|
|
(float)v.P2.getY());
|
|
else if(v instanceof CubicSegment)
|
|
p.curveTo((float)((CubicSegment)v).cp1.getX(),
|
|
(float)((CubicSegment)v).cp1.getY(),
|
|
(float)((CubicSegment)v).cp2.getX(),
|
|
(float)((CubicSegment)v).cp2.getY(),
|
|
(float)v.P2.getX(),
|
|
(float)v.P2.getY());
|
|
v = v.next;
|
|
} while(v != s && v != null);
|
|
|
|
p.closePath();
|
|
}
|
|
|
|
/**
|
|
* Add the segments to start and end (the inner and outer edges of the stroke)
|
|
*/
|
|
private void addSegments(Segment[] segments)
|
|
{
|
|
joinSegments(segments);
|
|
start.add(segments[0]);
|
|
end.add(segments[1]);
|
|
}
|
|
|
|
private void joinSegments(Segment[] segments)
|
|
{
|
|
double[] p0 = start.last.cp2();
|
|
double[] p1 = new double[]{start.last.P2.getX(), start.last.P2.getY()};
|
|
double[] p2 = new double[]{segments[0].first.P1.getX(), segments[0].first.P1.getY()};
|
|
double[] p3 = segments[0].cp1();
|
|
Point2D p;
|
|
|
|
p = lineIntersection(p0[0],p0[1],p1[0],p1[1],
|
|
p2[0],p2[1],p3[0],p3[1], false);
|
|
|
|
double det = (p1[0] - p0[0])*(p3[1] - p2[1]) -
|
|
(p3[0] - p2[0])*(p1[1] - p0[1]);
|
|
|
|
if( det > 0 )
|
|
{
|
|
// start and segment[0] form the 'inner' part of a join,
|
|
// connect the overlapping segments
|
|
joinInnerSegments(start, segments[0], p);
|
|
joinOuterSegments(end, segments[1], p);
|
|
}
|
|
else
|
|
{
|
|
// end and segment[1] form the 'inner' part
|
|
joinInnerSegments(end, segments[1], p);
|
|
joinOuterSegments(start, segments[0], p);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Make a cap between a and b segments,
|
|
* where a-->b is the direction of iteration.
|
|
*/
|
|
private void capEnd(Segment a, Segment b)
|
|
{
|
|
double[] p0, p1;
|
|
double dx, dy, l;
|
|
Point2D c1,c2;
|
|
|
|
switch( cap )
|
|
{
|
|
case CAP_BUTT:
|
|
a.add(new LineSegment(a.last.P2, b.P1));
|
|
break;
|
|
|
|
case CAP_SQUARE:
|
|
p0 = a.last.cp2();
|
|
p1 = new double[]{a.last.P2.getX(), a.last.P2.getY()};
|
|
dx = p1[0] - p0[0];
|
|
dy = p1[1] - p0[1];
|
|
l = Math.sqrt(dx * dx + dy * dy);
|
|
dx = 0.5*width*dx/l;
|
|
dy = 0.5*width*dy/l;
|
|
c1 = new Point2D.Double(p1[0] + dx, p1[1] + dy);
|
|
c2 = new Point2D.Double(b.P1.getX() + dx, b.P1.getY() + dy);
|
|
a.add(new LineSegment(a.last.P2, c1));
|
|
a.add(new LineSegment(c1, c2));
|
|
a.add(new LineSegment(c2, b.P1));
|
|
break;
|
|
|
|
case CAP_ROUND:
|
|
p0 = a.last.cp2();
|
|
p1 = new double[]{a.last.P2.getX(), a.last.P2.getY()};
|
|
dx = p1[0] - p0[0];
|
|
dy = p1[1] - p0[1];
|
|
if (dx != 0 && dy != 0)
|
|
{
|
|
l = Math.sqrt(dx * dx + dy * dy);
|
|
dx = (2.0/3.0)*width*dx/l;
|
|
dy = (2.0/3.0)*width*dy/l;
|
|
}
|
|
|
|
c1 = new Point2D.Double(p1[0] + dx, p1[1] + dy);
|
|
c2 = new Point2D.Double(b.P1.getX() + dx, b.P1.getY() + dy);
|
|
a.add(new CubicSegment(a.last.P2, c1, c2, b.P1));
|
|
break;
|
|
}
|
|
a.add(b);
|
|
}
|
|
|
|
/**
|
|
* Returns the intersection of two lines, or null if there isn't one.
|
|
* @param infinite - true if the lines should be regarded as infinite, false
|
|
* if the intersection must be within the given segments.
|
|
* @return a Point2D or null.
|
|
*/
|
|
private Point2D lineIntersection(double X1, double Y1,
|
|
double X2, double Y2,
|
|
double X3, double Y3,
|
|
double X4, double Y4,
|
|
boolean infinite)
|
|
{
|
|
double x1 = X1;
|
|
double y1 = Y1;
|
|
double rx = X2 - x1;
|
|
double ry = Y2 - y1;
|
|
|
|
double x2 = X3;
|
|
double y2 = Y3;
|
|
double sx = X4 - x2;
|
|
double sy = Y4 - y2;
|
|
|
|
double determinant = sx * ry - sy * rx;
|
|
double nom = (sx * (y2 - y1) + sy * (x1 - x2));
|
|
|
|
// lines can be considered parallel.
|
|
if (Math.abs(determinant) < 1E-6)
|
|
return null;
|
|
|
|
nom = nom / determinant;
|
|
|
|
// check if lines are within the bounds
|
|
if(!infinite && (nom > 1.0 || nom < 0.0))
|
|
return null;
|
|
|
|
return new Point2D.Double(x1 + nom * rx, y1 + nom * ry);
|
|
}
|
|
|
|
/**
|
|
* Join a and b segments, where a-->b is the direction of iteration.
|
|
*
|
|
* insideP is the inside intersection point of the join, needed for
|
|
* calculating miter lengths.
|
|
*/
|
|
private void joinOuterSegments(Segment a, Segment b, Point2D insideP)
|
|
{
|
|
double[] p0, p1;
|
|
double dx, dy, l;
|
|
Point2D c1,c2;
|
|
|
|
switch( join )
|
|
{
|
|
case JOIN_MITER:
|
|
p0 = a.last.cp2();
|
|
p1 = new double[]{a.last.P2.getX(), a.last.P2.getY()};
|
|
double[] p2 = new double[]{b.P1.getX(), b.P1.getY()};
|
|
double[] p3 = b.cp1();
|
|
Point2D p = lineIntersection(p0[0],p0[1],p1[0],p1[1],p2[0],p2[1],p3[0],p3[1], true);
|
|
if( p == null || insideP == null )
|
|
a.add(new LineSegment(a.last.P2, b.P1));
|
|
else if((p.distance(insideP)/width) < limit)
|
|
{
|
|
a.add(new LineSegment(a.last.P2, p));
|
|
a.add(new LineSegment(p, b.P1));
|
|
}
|
|
else
|
|
{
|
|
// outside miter limit, do a bevel join.
|
|
a.add(new LineSegment(a.last.P2, b.P1));
|
|
}
|
|
break;
|
|
|
|
case JOIN_ROUND:
|
|
p0 = a.last.cp2();
|
|
p1 = new double[]{a.last.P2.getX(), a.last.P2.getY()};
|
|
dx = p1[0] - p0[0];
|
|
dy = p1[1] - p0[1];
|
|
l = Math.sqrt(dx * dx + dy * dy);
|
|
dx = 0.5*width*dx/l;
|
|
dy = 0.5*width*dy/l;
|
|
c1 = new Point2D.Double(p1[0] + dx, p1[1] + dy);
|
|
|
|
p0 = new double[]{b.P1.getX(), b.P1.getY()};
|
|
p1 = b.cp1();
|
|
|
|
dx = p0[0] - p1[0]; // backwards direction.
|
|
dy = p0[1] - p1[1];
|
|
l = Math.sqrt(dx * dx + dy * dy);
|
|
dx = 0.5*width*dx/l;
|
|
dy = 0.5*width*dy/l;
|
|
c2 = new Point2D.Double(p0[0] + dx, p0[1] + dy);
|
|
a.add(new CubicSegment(a.last.P2, c1, c2, b.P1));
|
|
break;
|
|
|
|
case JOIN_BEVEL:
|
|
a.add(new LineSegment(a.last.P2, b.P1));
|
|
break;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Join a and b segments, removing any overlap
|
|
*/
|
|
private void joinInnerSegments(Segment a, Segment b, Point2D p)
|
|
{
|
|
double[] p0 = a.last.cp2();
|
|
double[] p1 = new double[] { a.last.P2.getX(), a.last.P2.getY() };
|
|
double[] p2 = new double[] { b.P1.getX(), b.P1.getY() };
|
|
double[] p3 = b.cp1();
|
|
|
|
if (p == null)
|
|
{
|
|
// Dodgy.
|
|
a.add(new LineSegment(a.last.P2, b.P1));
|
|
p = new Point2D.Double((b.P1.getX() + a.last.P2.getX()) / 2.0,
|
|
(b.P1.getY() + a.last.P2.getY()) / 2.0);
|
|
}
|
|
else
|
|
// This assumes segments a and b are single segments, which is
|
|
// incorrect - if they are a linked list of segments (ie, passed in
|
|
// from a flattening operation), this produces strange results!!
|
|
a.last.P2 = b.P1 = p;
|
|
}
|
|
}
|