001    /* ImageGraphicAttribute.java
002       Copyright (C) 2003 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package java.awt.font;
040    
041    import java.awt.Graphics2D;
042    import java.awt.Image;
043    import java.awt.geom.Rectangle2D;
044    
045    /**
046     * This is an implementation of GraphicAttribute which draws images in a
047     * TextLayout.
048     *
049     * @author Lillian Angel
050     * @author Michael Koch
051     */
052    public final class ImageGraphicAttribute
053        extends GraphicAttribute
054    {
055      private Image image;
056      private float originX;
057      private float originY;
058    
059      /**
060       * Constucts an instance from the specified Image. The origin is at (0, 0).
061       *
062       * @param image - image to construct from.
063       * @param alignment - the alignment
064       */
065      public ImageGraphicAttribute(Image image, int alignment)
066      {
067        this(image, alignment, 0, 0);
068      }
069    
070      /**
071       * Constucts an instance from the specified Image. The origin is at (originX,
072       * originY).
073       *
074       * @param image - image to construct from
075       * @param alignment - the alignment
076       * @param originX - x point of origin
077       * @param originY - y point of origin
078       */
079      public ImageGraphicAttribute(Image image, int alignment, float originX,
080                                   float originY)
081      {
082        super(alignment);
083        this.image = image;
084        this.originX = originX;
085        this.originY = originY;
086      }
087    
088      /**
089       * Draws the image at the specified location, relative to the
090       * origin.
091       *
092       * @param g - the graphics to use to render the image
093       * @param x - the x location
094       * @param y - the y location
095       */
096      public void draw(Graphics2D g, float x, float y)
097      {
098        g.drawImage(image, (int) (x - originX), (int) (y - originY), null);
099      }
100    
101      /**
102       * Compares this to the specified Object
103       *
104       * @param obj - the object to compare
105       * @return true if the obj and this are equivalent
106       */
107      public boolean equals(Object obj)
108      {
109        if (! (obj instanceof ImageGraphicAttribute))
110          return false;
111    
112        return equals((ImageGraphicAttribute) obj);
113      }
114    
115      /**
116       * Compares this to the ImageGraphicAttribute given, by
117       * comparing all fields and values.
118       *
119       * @param rhs - the ImageGraphicAttribute to compare
120       * @return true if the object given is equivalent to this
121       */
122      public boolean equals(ImageGraphicAttribute rhs)
123      {
124        return ((this == rhs) || ((this.getAscent() == rhs.getAscent())
125                                  && (this.getAdvance() == rhs.getAdvance())
126                                  && (this.getAlignment() == rhs.getAlignment())
127                                  && (this.getBounds().equals(rhs.getBounds()))
128                                  && (this.getDescent() == rhs.getDescent())
129                                  && (this.hashCode() == rhs.hashCode())
130                                  && (this.image.equals(rhs.image))
131                                  && (this.originX == rhs.originX)
132                                  && (this.originY == rhs.originY)));
133      }
134    
135      /**
136       * Returns distance from the origin to the right edge of the image of this.
137       *
138       * @return the advance
139       */
140      public float getAdvance()
141      {
142        return Math.max(0, image.getWidth(null) - originX);
143      }
144    
145      /**
146       * Returns the the distance from the top of the image to the origin of this.
147       *
148       * @return the ascent.
149       */
150      public float getAscent()
151      {
152        return Math.max(0, originY);
153      }
154    
155      /**
156       * Gets the bounds of the object rendered, relative to the position.
157       *
158       * @return the bounds of the object rendered, relative to the position.
159       */
160      public Rectangle2D getBounds()
161      {
162        // This is equivalent to what Sun's JDK returns.
163        // I am not entirely sure why the origin is negative.
164        return new Rectangle2D.Float(- originX, - originY, image.getWidth(null),
165                                     image.getHeight(null));
166      }
167    
168      /**
169       * Returns the distance from the origin to the bottom of the image.
170       *
171       * @return the descent
172       */
173      public float getDescent()
174      {
175        return Math.max(0, image.getHeight(null) - originY);
176      }
177    
178      /**
179       * Gets the hash code for this image.
180       *
181       * @return the hash code
182       */
183      public int hashCode()
184      {
185        return image.hashCode();
186      }
187    }