apps/konsole/src/CharacterColor.h

   1 /*
   2     This file is part of Konsole, KDE's terminal.
   3
   4     Copyright 2007-2008 by Robert Knight <robertknight@gmail.com>
   5     Copyright 1997,1998 by Lars Doelle <lars.doelle@on-line.de>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License
  18     along with this program; if not, write to the Free Software
  19     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20     02110-1301  USA.
  21 */
  22
  23 #ifndef CHARACTERCOLOR_H
  24 #define CHARACTERCOLOR_H
  25
  26 // Qt
  27 #include <QtGui/QColor>
  28
  29 #include <kdemacros.h>
  30
  31 namespace Konsole
  32 {
  33
  34 /**
  35  * An entry in a terminal display's color palette.
  36  *
  37  * A color palette is an array of 16 ColorEntry instances which map
  38  * system color indexes (from 0 to 15) into actual colors.
  39  *
  40  * Each entry can be set as bold, in which case any text
  41  * drawn using the color should be drawn in bold.
  42  *
  43  * Each entry can also be transparent, in which case the terminal
  44  * display should avoid drawing the background for any characters
  45  * using the entry as a background.
  46  */
  47 class ColorEntry
  48 {
  49 public:
  50   /** Specifies the weight to use when drawing text with this color. */
  51   enum FontWeight
  52   {
  53     /** Always draw text in this color with a bold weight. */
  54     Bold,
  55     /** Always draw text in this color with a normal weight. */
  56     Normal,
  57     /**
  58      * Use the current font weight set by the terminal application.
  59      * This is the default behavior.
  60      */
  61     UseCurrentFormat
  62   };
  63
  64   /**
  65    * Constructs a new color palette entry.
  66    *
  67    * @param c The color value for this entry.
  68    * @param tr Specifies that the color should be transparent when used as a background color.
  69    * @param b Specifies that text drawn with this color should be bold.
  70    */
  71   ColorEntry(QColor c, bool tr, FontWeight weight = UseCurrentFormat)
  72           : color(c), transparent(tr), fontWeight(weight) {}
  73
  74   /**
  75    * Constructs a new color palette entry with an undefined color, and
  76    * with the transparent and bold flags set to false.
  77    */
  78   ColorEntry() : transparent(false), fontWeight(UseCurrentFormat) {}
  79
  80   /**
  81    * Sets the color, transparency and boldness of this color to those of @p rhs.
  82    */
  83   void operator=(const ColorEntry& rhs)
  84   {
  85        color = rhs.color;
  86        transparent = rhs.transparent;
  87        fontWeight = rhs.fontWeight;
  88   }
  89
  90   /** The color value of this entry for display. */
  91   QColor color;
  92
  93   /**
  94    * If true character backgrounds using this color should be transparent.
  95    * This is not applicable when the color is used to render text.
  96    */
  97   bool   transparent;
  98   /**
  99    * Specifies the font weight to use when drawing text with this color.
 100    * This is not applicable when the color is used to draw a character's background.
 101    */
 102   FontWeight fontWeight;
 103 };
 104
 105
 106 // Attributed Character Representations ///////////////////////////////
 107
 108 // Colors
 109
 110 #define BASE_COLORS   (2+8)
 111 #define INTENSITIES   2
 112 #define TABLE_COLORS  (INTENSITIES*BASE_COLORS)
 113
 114 #define DEFAULT_FORE_COLOR 0
 115 #define DEFAULT_BACK_COLOR 1
 116
 117 //a standard set of colors using black text on a white background.
 118 //defined in TerminalDisplay.cpp
 119
 120 extern const ColorEntry base_color_table[TABLE_COLORS] KDE_NO_EXPORT;
 121
 122 /* CharacterColor is a union of the various color spaces.
 123
 124    Assignment is as follows:
 125
 126    Type  - Space        - Values
 127
 128    0     - Undefined   - u:  0,      v:0        w:0
 129    1     - Default     - u:  0..1    v:intense  w:0
 130    2     - System      - u:  0..7    v:intense  w:0
 131    3     - Index(256)  - u: 16..255  v:0        w:0
 132    4     - RGB         - u:  0..255  v:0..256   w:0..256
 133
 134    Default colour space has two separate colours, namely
 135    default foreground and default background colour.
 136 */
 137
 138 #define COLOR_SPACE_UNDEFINED   0
 139 #define COLOR_SPACE_DEFAULT     1
 140 #define COLOR_SPACE_SYSTEM      2
 141 #define COLOR_SPACE_256         3
 142 #define COLOR_SPACE_RGB         4
 143
 144 /**
 145  * Describes the color of a single character in the terminal.
 146  */
 147 class CharacterColor
 148 {
 149     friend class Character;
 150
 151 public:
 152   /** Constructs a new CharacterColor whoose color and color space are undefined. */
 153   CharacterColor()
 154       : _colorSpace(COLOR_SPACE_UNDEFINED),
 155         _u(0),
 156         _v(0),
 157         _w(0)
 158   {}
 159
 160   /**
 161    * Constructs a new CharacterColor using the specified @p colorSpace and with
 162    * color value @p co
 163    *
 164    * The meaning of @p co depends on the @p colorSpace used.
 165    *
 166    * TODO : Document how @p co relates to @p colorSpace
 167    *
 168    * TODO : Add documentation about available color spaces.
 169    */
 170   CharacterColor(quint8 colorSpace, int co)
 171       : _colorSpace(colorSpace),
 172         _u(0),
 173         _v(0),
 174         _w(0)
 175   {
 176     switch (colorSpace)
 177     {
 178         case COLOR_SPACE_DEFAULT:
 179             _u = co & 1;
 180             break;
 181         case COLOR_SPACE_SYSTEM:
 182             _u = co & 7;
 183             _v = (co >> 3) & 1;
 184             break;
 185         case COLOR_SPACE_256:
 186             _u = co & 255;
 187             break;
 188         case COLOR_SPACE_RGB:
 189             _u = co >> 16;
 190             _v = co >> 8;
 191             _w = co;
 192             break;
 193         default:
 194             _colorSpace = COLOR_SPACE_UNDEFINED;
 195     }
 196   }
 197
 198   /**
 199    * Returns true if this character color entry is valid.
 200    */
 201   bool isValid()
 202   {
 203         return _colorSpace != COLOR_SPACE_UNDEFINED;
 204   }
 205
 206   /**
 207    * Toggles the value of this color between a normal system color and the corresponding intensive
 208    * system color.
 209    *
 210    * This is only applicable if the color is using the COLOR_SPACE_DEFAULT or COLOR_SPACE_SYSTEM
 211    * color spaces.
 212    */
 213   void toggleIntensive();
 214
 215   /**
 216    * Returns the color within the specified color @palette
 217    *
 218    * The @p palette is only used if this color is one of the 16 system colors, otherwise
 219    * it is ignored.
 220    */
 221   QColor color(const ColorEntry* palette) const;
 222
 223   /**
 224    * Compares two colors and returns true if they represent the same color value and
 225    * use the same color space.
 226    */
 227   friend bool operator == (const CharacterColor& a, const CharacterColor& b);
 228   /**
 229    * Compares two colors and returns true if they represent different color values
 230    * or use different color spaces.
 231    */
 232   friend bool operator != (const CharacterColor& a, const CharacterColor& b);
 233
 234 private:
 235   quint8 _colorSpace;
 236
 237   // bytes storing the character color
 238   quint8 _u;
 239   quint8 _v;
 240   quint8 _w;
 241 };
 242
 243 inline bool operator == (const CharacterColor& a, const CharacterColor& b)
 244 {
 245     return     a._colorSpace == b._colorSpace &&
 246             a._u == b._u &&
 247             a._v == b._v &&
 248             a._w == b._w;
 249 }
 250 inline bool operator != (const CharacterColor& a, const CharacterColor& b)
 251 {
 252     return !operator==(a,b);
 253 }
 254
 255 inline const QColor color256(quint8 u, const ColorEntry* base)
 256 {
 257   //   0.. 16: system colors
 258   if (u <   8) return base[u+2            ].color; u -= 8;
 259   if (u <   8) return base[u+2+BASE_COLORS].color; u -= 8;
 260
 261   //  16..231: 6x6x6 rgb color cube
 262   if (u < 216) return QColor(((u/36)%6) ? (40*((u/36)%6)+55) : 0,
 263                              ((u/ 6)%6) ? (40*((u/ 6)%6)+55) : 0,
 264                              ((u/ 1)%6) ? (40*((u/ 1)%6)+55) : 0); u -= 216;
 265
 266   // 232..255: gray, leaving out black and white
 267   int gray = u*10+8; return QColor(gray,gray,gray);
 268 }
 269
 270 inline QColor CharacterColor::color(const ColorEntry* base) const
 271 {
 272   switch (_colorSpace)
 273   {
 274     case COLOR_SPACE_DEFAULT: return base[_u+0+(_v?BASE_COLORS:0)].color;
 275     case COLOR_SPACE_SYSTEM: return base[_u+2+(_v?BASE_COLORS:0)].color;
 276     case COLOR_SPACE_256: return color256(_u,base);
 277     case COLOR_SPACE_RGB: return QColor(_u,_v,_w);
 278     case COLOR_SPACE_UNDEFINED: return QColor();
 279   }
 280
 281   Q_ASSERT(false); // invalid color space
 282
 283   return QColor();
 284 }
 285
 286 inline void CharacterColor::toggleIntensive()
 287 {
 288   if (_colorSpace == COLOR_SPACE_SYSTEM || _colorSpace == COLOR_SPACE_DEFAULT)
 289   {
 290     _v = !_v;
 291   }
 292 }
 293
 294
 295 }
 296
 297 #endif // CHARACTERCOLOR_H
 298