Source for gnu.java.awt.peer.gtk.GdkFontMetrics

   1: /* GdkFontMetrics.java
   2:    Copyright (C) 1999, 2002, 2004, 2005  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 gnu.java.awt.peer.gtk;
  40: 
  41: import gnu.java.awt.ClasspathToolkit;
  42: 
  43: import java.awt.Font;
  44: import java.awt.FontMetrics;
  45: import java.awt.Toolkit;
  46: 
  47: public class GdkFontMetrics extends FontMetrics
  48: {
  49:   
  50:   private int[] font_metrics;
  51:   GdkFontPeer peer;
  52: 
  53:   static final int FONT_METRICS_ASCENT = 0;
  54:   static final int FONT_METRICS_MAX_ASCENT = 1;
  55:   static final int FONT_METRICS_DESCENT = 2;
  56:   static final int FONT_METRICS_MAX_DESCENT = 3;
  57:   static final int FONT_METRICS_MAX_ADVANCE = 4;
  58: 
  59:   static final int TEXT_METRICS_X_BEARING = 0;
  60:   static final int TEXT_METRICS_Y_BEARING = 1;
  61:   static final int TEXT_METRICS_WIDTH = 2;
  62:   static final int TEXT_METRICS_HEIGHT = 3;
  63:   static final int TEXT_METRICS_X_ADVANCE = 4;
  64:   static final int TEXT_METRICS_Y_ADVANCE = 5;
  65:   
  66:   /**
  67:    * Makes sure to return a Font based on the given Font that has as
  68:    * peer a GdkFontPeer. Used in the initializer.
  69:    */
  70:   private static Font initFont(Font font)
  71:   {
  72:     if (font == null)
  73:       return new Font("Dialog", Font.PLAIN, 12);
  74:     else if (font.getPeer() instanceof GdkFontPeer)
  75:       return font;
  76:     else
  77:       {
  78:     ClasspathToolkit toolkit;
  79:     toolkit = (ClasspathToolkit) Toolkit.getDefaultToolkit();
  80:     return toolkit.getFont(font.getName(), font.getAttributes());
  81:       }
  82:   }
  83:     
  84:   public GdkFontMetrics (Font font)
  85:   {    
  86:     super(initFont(font));
  87:     peer = (GdkFontPeer) this.font.getPeer();
  88: 
  89:     font_metrics = new int[5];
  90:     double [] hires = new double[5];
  91:     peer.getFontMetrics (hires);
  92:     for (int i = 0; i < 5; ++i)
  93:       font_metrics[i] = (int) hires[i];
  94:   }
  95:   
  96:   public int stringWidth (String str)
  97:   {
  98:     double [] hires = new double[6];
  99:     peer.getTextMetrics(str, hires);
 100:     return (int) hires [TEXT_METRICS_WIDTH];
 101:   }
 102: 
 103:   public int charWidth (char ch)
 104:   {
 105:     return stringWidth (new String (new char[] { ch }));
 106:   }
 107: 
 108:   public int charsWidth (char data[], int off, int len)
 109:   {
 110:     return stringWidth (new String (data, off, len));
 111:   }
 112: 
 113:   public int getLeading ()
 114:   {
 115:     // Sun always returns 0.
 116:     return 0;
 117:   }
 118: 
 119:   public int getAscent ()
 120:   {
 121:     return font_metrics[FONT_METRICS_ASCENT];
 122:   }
 123: 
 124:   public int getMaxAscent ()
 125:   {
 126:     return font_metrics[FONT_METRICS_MAX_ASCENT];
 127:   }
 128: 
 129:   public int getDescent ()
 130:   {
 131:     return font_metrics[FONT_METRICS_DESCENT];
 132:   }
 133: 
 134:   public int getMaxDescent ()
 135:   {
 136:     return font_metrics[FONT_METRICS_MAX_DESCENT];
 137:   }
 138: 
 139:   public int getMaxAdvance ()
 140:   {
 141:     return font_metrics[FONT_METRICS_MAX_ADVANCE];
 142:   }
 143: }