001/* SoftBevelBorder.java --
002   Copyright (C) 2003 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038package javax.swing.border;
039
040import java.awt.Color;
041import java.awt.Component;
042import java.awt.Graphics;
043import java.awt.Insets;
044
045
046/**
047 * A rectangular, three pixel thick border that looks like a BevelBorder
048 * with slightly softened corners.
049 *
050 * <p>Like BevelBorder, SoftBevelBorder has a highlight and a shadow
051 * color. In the raised variant, the highlight color is used for the
052 * top and left edges, and the shadow color is used for the bottom and
053 * right edge.  In the lowered variant, color usage is reversed.  For
054 * an image, see the documentation of the individual constructors.
055 *
056 * @author Sascha Brawer (brawer@dandelis.ch)
057 */
058public class SoftBevelBorder extends BevelBorder
059{
060  /**
061   * Determined using the <code>serialver</code> tool
062   * of Sun JDK 1.4.1_01 on GNU/Linux 2.4.20. Interestingly,
063   * the Apple/Sun JDK 1.3.1 on MacOS X 10.1.5 gives a different
064   * value, namely -6658357140774549493L.
065   */
066  static final long serialVersionUID = 5248789787305979975L;
067
068
069  /**
070   * Constructs a SoftBevelBorder whose colors will be derived from the
071   * background of the enclosed component. The background color is
072   * retrieved each time the border is painted, so a SoftBevelBorder
073   * constructed by this method will automatically reflect a change
074   * to the component&#x2019;s background color.
075   *
076   * <p><img src="doc-files/SoftBevelBorder-1.png" width="500" height="200"
077   * alt="[An illustration showing raised and lowered SoftBevelBorders]" />
078   *
079   * @param bevelType the desired appearance of the border. The value
080   *        must be either {@link BevelBorder#RAISED}
081   *        or {@link BevelBorder#LOWERED}.
082   *
083   * @throws IllegalArgumentException if <code>bevelType</code> has
084   *         an unsupported value.
085   */
086  public SoftBevelBorder(int bevelType)
087  {
088    super(bevelType);
089  }
090
091
092  /**
093   * Constructs a SoftBevelBorder given its appearance type and two
094   * colors for its highlight and shadow.
095   *
096   * <p><img src="doc-files/SoftBevelBorder-2.png" width="500" height="150"
097   * alt="[An illustration showing SoftBevelBorders that were
098   * constructed with this method]" />
099   *
100   * @param bevelType the desired appearance of the border. The value
101   *        must be either {@link BevelBorder#RAISED} or {@link
102   *        BevelBorder#LOWERED}.
103   *
104   * @param highlight the color that will be used for the inner side
105   *        of the highlighted edges (top and left if if
106   *        <code>bevelType</code> is {@link BevelBorder#RAISED};
107   *        bottom and right otherwise). The color for the outer side
108   *        is a brightened version of this color.
109   *
110   * @param shadow the color that will be used for the outer side of
111   *        the shadowed edges (bottom and right if
112   *        <code>bevelType</code> is {@link BevelBorder#RAISED}; top
113   *        and left otherwise). The color for the inner side is a
114   *        brightened version of this color.
115   *
116   * @throws IllegalArgumentException if <code>bevelType</code> has an
117   *        unsupported value.
118   *
119   * @throws NullPointerException if <code>highlight</code> or
120   *         <code>shadow</code> is <code>null</code>.
121   *
122   * @see java.awt.Color#brighter()
123   */
124  public SoftBevelBorder(int bevelType, Color highlight, Color shadow)
125  {
126    this(bevelType,
127         /* highlightOuter */ highlight.brighter(),
128         /* highlightInner */ highlight,
129         /* shadowOuter */    shadow,
130         /* shadowInner */    shadow.brighter());
131  }
132
133
134  /**
135   * Constructs a SoftBevelBorder given its appearance type and all
136   * colors.
137   *
138   * <p><img src="doc-files/SoftBevelBorder-3.png" width="500" height="150"
139   * alt="[An illustration showing SoftBevelBorders that were
140   * constructed with this method]" />
141   *
142   * @param bevelType the desired appearance of the border. The value
143   *        must be either {@link BevelBorder#RAISED} or {@link
144   *        BevelBorder#LOWERED}.
145   *
146   * @param highlightOuter the color that will be used for the outer
147   *        side of the highlighted edges (top and left if
148   *        <code>bevelType</code> is {@link BevelBorder#RAISED};
149   *        bottom and right otherwise).
150   *
151   * @param highlightInner the color that will be used for the inner
152   *        side of the highlighted edges.
153   *
154   * @param shadowOuter the color that will be used for the outer side
155   *        of the shadowed edges (bottom and right if
156   *        <code>bevelType</code> is {@link BevelBorder#RAISED}; top
157   *        and left otherwise).
158   *
159   * @param shadowInner the color that will be used for the inner
160   *        side of the shadowed edges.
161   *
162   * @throws IllegalArgumentException if <code>bevelType</code> has
163   *         an unsupported value.
164   *
165   * @throws NullPointerException if one of the passed colors
166   *         is <code>null</code>.
167   */
168  public SoftBevelBorder(int bevelType,
169                         Color highlightOuter, Color highlightInner,
170                         Color shadowOuter, Color shadowInner)
171  {
172    super(bevelType,
173          highlightOuter, highlightInner,
174          shadowOuter, shadowInner);
175  }
176
177
178  /**
179   * Paints the border for a given component.
180   *
181   * @param c the component whose border is to be painted.
182   * @param g the graphics for painting.
183   * @param x the horizontal position for painting the border.
184   * @param y the vertical position for painting the border.
185   * @param width the width of the available area for painting the border.
186   * @param height the height of the available area for painting the border.
187   */
188  public void paintBorder(Component c, Graphics  g,
189                          int x, int y, int width, int height)
190  {
191    switch (bevelType)
192    {
193    case RAISED:
194      paintSoftBevel(g, x, y, width, height,
195                     getHighlightOuterColor(c), getHighlightInnerColor(c),
196                     getShadowInnerColor(c), getShadowOuterColor(c));
197      break;
198
199    case LOWERED:
200      paintSoftBevel(g, x, y, width, height,
201                     getShadowOuterColor(c), getShadowInnerColor(c),
202                     getHighlightInnerColor(c), getHighlightOuterColor(c));
203      break;
204    }
205  }
206
207
208  /**
209   * Measures the width of this border.
210   *
211   * @param c the component whose border is to be measured.
212   *
213   * @return an Insets object whose <code>left</code>, <code>right</code>,
214   *         <code>top</code> and <code>bottom</code> fields indicate the
215   *         width of the border at the respective edge.
216   *
217   * @see #getBorderInsets(java.awt.Component, java.awt.Insets)
218   */
219  public Insets getBorderInsets(Component c)
220  {
221    return new Insets(3, 3, 3, 3);
222  }
223
224
225  /**
226   * Measures the width of this border, storing the results into a
227   * pre-existing Insets object.
228   *
229   * @param insets an Insets object for holding the result values.
230   *        After invoking this method, the <code>left</code>,
231   *        <code>right</code>, <code>top</code> and
232   *        <code>bottom</code> fields indicate the width of the
233   *        border at the respective edge.
234   *
235   * @return the same object that was passed for <code>insets</code>.
236   *
237   * @see #getBorderInsets(Component)
238   */
239  public Insets getBorderInsets(Component c, Insets insets)
240  {
241    insets.left = insets.right = insets.top = insets.bottom = 3;
242    return insets;
243  }
244
245
246  /**
247   * Determines whether this border fills every pixel in its area
248   * when painting.
249   *
250   * <p>The enlarged view (see documentation for constructors) shows
251   * that a SoftBevelBorder does not paint all pixels. Therefore,
252   * this method always returns <code>false</code>.
253   *
254   * @return <code>false</code>.
255   */
256  public boolean isBorderOpaque()
257  {
258    return false;
259  }
260
261
262  /**
263   * Paints a soft bevel in four colors.
264   *
265   * <pre>
266   * +++++++++++.
267   * ++.........#    + = color a
268   * +..        #    . = color b
269   * +.         #    X = color c
270   * ..        X#    # = color d
271   * . ##########</pre>
272   *
273   * @param g the graphics for painting.
274   * @param x the horizontal position for painting the border.
275   * @param y the vertical position for painting the border.
276   * @param width the width of the available area for painting the border.
277   * @param height the height of the available area for painting the border.
278   * @param a the color for the outer side of the top and left edges.
279   * @param b the color for the inner side of the top and left edges.
280   * @param c the color for the inner side of the bottom and right edges.
281   * @param d the color for the outer side of the bottom and right edges.
282   */
283  private static void paintSoftBevel(Graphics g,
284                                     int x, int y, int width, int height,
285                                     Color a, Color b, Color c, Color d)
286  {
287    Color oldColor;
288
289    oldColor = g.getColor();
290    g.translate(x, y);
291    width = width - 1;
292    height = height - 1;
293
294    try
295    {
296      /* To understand this code, it might be helpful to look at the
297       * images that are included with the JavaDoc, especially
298       * SoftBevelBorder-3.png. They are located in the "doc-files"
299       * subdirectory.
300       */
301      g.setColor(a);
302      g.drawLine(0, 0, width - 1, 0);                   // a, horizontal
303      g.drawLine(0, 1, 2, 1);                           // a, horizontal
304      g.drawLine(0, 2, 0, height - 1);                  // a, vertical
305
306      g.setColor(b);
307      g.drawLine(width, 0, width, 0);                   // b, horizontal
308      g.drawLine(2, 1, width - 1, 1);                   // b, horizontal
309      g.drawLine(1, 2, 2, 2);                           // b, horizontal
310      g.drawLine(1, 3, 1, height - 1);                  // b, vertical
311      g.drawLine(0, height - 1, 0, height);             // b, vertical
312
313      g.setColor(c);
314      g.drawLine(width - 1, height - 1,                 // c, one pixel
315                 width - 1, height - 1);
316
317      g.setColor(d);
318      g.drawLine(2, height, width, height);             // d, horizontal
319      g.drawLine(width, 2, width, height - 1);          // d, vertical
320    }
321    finally
322    {
323      g.translate(-x, -y);
324      g.setColor(oldColor);
325    }
326  }
327}