Source for java.awt.font.ImageGraphicAttribute

   1: /* ImageGraphicAttribute.java
   2:    Copyright (C) 2003 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package java.awt.font;
  40: 
  41: import java.awt.Graphics2D;
  42: import java.awt.Image;
  43: import java.awt.geom.Rectangle2D;
  44: 
  45: /**
  46:  * This is an implementation of GraphicAttribute which draws images in a
  47:  * TextLayout.
  48:  * 
  49:  * @author Lillian Angel
  50:  * @author Michael Koch
  51:  */
  52: public final class ImageGraphicAttribute
  53:     extends GraphicAttribute
  54: {
  55:   private Image image;
  56:   private float originX;
  57:   private float originY;
  58: 
  59:   /**
  60:    * Constucts an instance from the specified Image. The origin is at (0, 0).
  61:    * 
  62:    * @param image - image to construct from.
  63:    * @param alignment - the alignment
  64:    */
  65:   public ImageGraphicAttribute(Image image, int alignment)
  66:   {
  67:     this(image, alignment, 0, 0);
  68:   }
  69: 
  70:   /**
  71:    * Constucts an instance from the specified Image. The origin is at (originX,
  72:    * originY).
  73:    * 
  74:    * @param image - image to construct from
  75:    * @param alignment - the alignment
  76:    * @param originX - x point of origin
  77:    * @param originY - y point of origin
  78:    */
  79:   public ImageGraphicAttribute(Image image, int alignment, float originX,
  80:                                float originY)
  81:   {
  82:     super(alignment);
  83:     this.image = image;
  84:     this.originX = originX;
  85:     this.originY = originY;
  86:   }
  87: 
  88:   /**
  89:    * Draws the image at the specified location, relative to the
  90:    * origin.
  91:    * 
  92:    * @param g - the graphics to use to render the image
  93:    * @param x - the x location
  94:    * @param y - the y location 
  95:    */
  96:   public void draw(Graphics2D g, float x, float y)
  97:   {
  98:     g.drawImage(image, (int) (x - originX), (int) (y - originY), null);
  99:   }
 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: }