src/frontends/xforms/ColorHandler.C

   1 /**
   2  * \file ColorHandler.C
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author unknown
   7  *
   8  * Full author contact details are available in file CREDITS.
   9  */
  10
  11 #include <config.h>
  12
  13 #include "ColorHandler.h"
  14
  15 #include "debug.h"
  16 #include "gettext.h"
  17 #include "LColor.h"
  18
  19 #include "support/lstrings.h"
  20 #include "support/convert.h"
  21
  22 #include "lyx_forms.h"
  23
  24 #include <boost/scoped_array.hpp>
  25
  26 #include <cmath>
  27
  28 #ifndef CXX_GLOBAL_CSTD
  29 using std::pow;
  30 #endif
  31
  32 using std::endl;
  33 using std::string;
  34
  35 namespace lyx {
  36
  37 namespace support {
  38 namespace {
  39
  40         string tostr(XColor const & col)
  41         {
  42                 return bformat("(%1$s,%2$s,%3$s)",
  43                                ::convert<string>(col.red),
  44                                ::convert<string>(col.green),
  45                                ::convert<string>(col.blue));
  46         }
  47
  48 } // namespace
  49 } // namespace support
  50
  51 using support::bformat;
  52 using support::tostr;
  53
  54
  55 namespace frontend {
  56
  57 LyXColorHandler::LyXColorHandler()
  58                 : colorGCcache(LColor::ignore + 1)
  59 {
  60         display = fl_get_display();
  61         drawable = XCreatePixmap(display,
  62                                  RootWindow(display, fl_screen),
  63                                  10, 10, fl_get_visual_depth());
  64
  65         colormap = fl_state[fl_get_vclass()].colormap;
  66         // Clear the GC cache
  67         for (string::size_type i = 0; i < colorGCcache.size(); ++i) {
  68                 colorGCcache[i] = 0;
  69         }
  70 }
  71
  72
  73 LyXColorHandler::~LyXColorHandler()
  74 {
  75         // Release all the registered GCs
  76         for (unsigned i = 0; i < colorGCcache.size(); ++i) {
  77                 if (colorGCcache[i] != 0) {
  78                         XFreeGC(display, colorGCcache[i]);
  79                 }
  80         }
  81         // Iterate over the line cache and Free the GCs
  82         for (LineGCCache::iterator lit = lineGCcache.begin();
  83              lit != lineGCcache.end(); ++lit) {
  84                 XFreeGC(display, lit->second);
  85         }
  86 }
  87
  88
  89 unsigned long LyXColorHandler::colorPixel(LColor_color c)
  90 {
  91         XGCValues val;
  92         XGetGCValues(display, getGCForeground(c), GCForeground, &val);
  93         return val.foreground;
  94 }
  95
  96
  97 GC LyXColorHandler::getGCForeground(string const & s)
  98 {
  99         XColor xcol;
 100         XColor ccol;
 101         XGCValues val;
 102         // Look up the RGB values for the color, and an approximate
 103         // color that we can hope to get on this display.
 104         if (XLookupColor(display, colormap, s.c_str(), &xcol, &ccol) == 0) {
 105                 lyxerr << bformat(
 106                         _("LyX: Unknown X11 color %1$s\n"
 107                           "     Using black instead, sorry!"),
 108                         s) << endl;
 109                 unsigned long bla = BlackPixel(display,
 110                                                DefaultScreen(display));
 111                 val.foreground = bla;
 112         // Try the exact RGB values first, then the approximate.
 113         } else if (XAllocColor(display, colormap, &xcol) != 0) {
 114                 if (lyxerr.debugging(Debug::GUI)) {
 115                         lyxerr << bformat(_("LyX: X11 color %1$s allocated"),
 116                                 s) << endl;
 117                 }
 118                 val.foreground = xcol.pixel;
 119         } else {
 120                 // Here we are traversing the current colormap to find
 121                 // the color closest to the one we want.
 122                 Visual * vi = DefaultVisual(display, DefaultScreen(display));
 123
 124                 boost::scoped_array<XColor> cmap(new XColor[vi->map_entries]);
 125
 126                 for (int i = 0; i < vi->map_entries; ++i) {
 127                         cmap[i].pixel = i;
 128                 }
 129                 XQueryColors(display, colormap, cmap.get(), vi->map_entries);
 130
 131                 // Walk through the cmap and look for close colors.
 132                 int closest_pixel = 0;
 133                 double closest_distance = 1e20; // we want to minimize this
 134                 double distance = 0;
 135                 for (int t = 0; t < vi->map_entries; ++t) {
 136                         // The Euclidean distance between two points in
 137                         // a three-dimensional space, the RGB color-cube,
 138                         // is used as the distance measurement between two
 139                         // colors.
 140
 141                         // Since square-root is monotonous, we don't have to
 142                         // take the square-root to find the minimum, and thus
 143                         // we use the squared distance instead to be faster.
 144
 145                         // If we want to get fancy, we could convert the RGB
 146                         // coordinates to a different color-cube, maybe HSV,
 147                         // but the RGB cube seems to work great.  (Asger)
 148                         distance = pow(cmap[t].red   - xcol.red,   2.0) +
 149                                    pow(cmap[t].green - xcol.green, 2.0) +
 150                                    pow(cmap[t].blue  - xcol.blue,  2.0);
 151                         if (distance < closest_distance) {
 152                                 closest_distance = distance;
 153                                 closest_pixel = t;
 154                         }
 155                 }
 156
 157                 lyxerr << bformat(
 158                         _("LyX: Couldn't allocate '%1$s' with (r,g,b)=%2$s.\n"),
 159                         s, tostr(xcol));
 160
 161                 lyxerr << bformat(
 162                                 _("     Using closest allocated color with (r,g,b)=%1$s instead.\n"
 163                           "Pixel [%2$s] is used."),
 164                         tostr(cmap[closest_pixel]), convert<string>(closest_pixel)) << endl;
 165
 166                 val.foreground = cmap[closest_pixel].pixel;
 167         }
 168         val.function = GXcopy;
 169         return XCreateGC(display, drawable,
 170                                            GCForeground | GCFunction, &val);
 171 }
 172
 173 // Gets GC according to color
 174 // Uses caching
 175 GC LyXColorHandler::getGCForeground(LColor_color c)
 176 {
 177         if (static_cast<unsigned>(c) >= colorGCcache.size()) {
 178                 colorGCcache.resize(c + 1, 0);
 179         }
 180
 181         if (colorGCcache[c] != 0) {
 182                 return colorGCcache[c];
 183         }
 184         XColor xcol;
 185         XColor ccol;
 186         string const s = lcolor.getX11Name(c);
 187         // Look up the RGB values for the color, and an approximate
 188         // color that we can hope to get on this display.
 189         if (XLookupColor(display, colormap, s.c_str(), &xcol, &ccol) == 0) {
 190                 lyxerr << bformat(
 191                         _("LyX: Unknown X11 color %1$s for %2$s\n"),
 192                         s, lcolor.getGUIName(c)) << endl;
 193         }
 194         return colorGCcache[c] = getGCForeground(s);
 195 }
 196
 197
 198 // Gets GC for line
 199 GC LyXColorHandler::getGCLinepars(Painter::line_style ls,
 200                                   Painter::line_width lw, LColor_color c)
 201 {
 202         //if (lyxerr.debugging()) {
 203         //      lyxerr << "Painter drawable: " << drawable() << endl;
 204         //}
 205
 206         int index = lw + (ls << 1) + (c << 6);
 207
 208         LineGCCache::iterator it = lineGCcache.find(index);
 209         if (it != lineGCcache.end())
 210                 return it->second;
 211
 212         XGCValues val;
 213         XGetGCValues(display, getGCForeground(c), GCForeground, &val);
 214
 215         switch (lw) {
 216         case Painter::line_thin:
 217                 val.line_width = 0;
 218                 break;
 219         case Painter::line_thick:
 220                 val.line_width = 2;
 221                 break;
 222         }
 223
 224         switch (ls) {
 225         case Painter::line_solid:
 226                 val.line_style = LineSolid;
 227                 break;
 228         case Painter::line_onoffdash:
 229                 val.line_style = LineOnOffDash;
 230                 break;
 231         }
 232
 233
 234         val.cap_style = CapRound;
 235         val.join_style = JoinRound;
 236         val.function = GXcopy;
 237
 238         return lineGCcache[index] =
 239                 XCreateGC(display, drawable,
 240                           GCForeground | GCLineStyle | GCLineWidth |
 241                           GCCapStyle | GCJoinStyle | GCFunction, &val);
 242 }
 243
 244
 245 // update GC cache after color redefinition
 246 void LyXColorHandler::updateColor (LColor_color c)
 247 {
 248         // color GC cache
 249         GC gc = colorGCcache[c];
 250         if (gc != 0) {
 251                 XFreeGC(display, gc);
 252                 colorGCcache[c] = NULL;
 253                 getGCForeground(c);
 254         }
 255
 256         // line GC cache
 257
 258         for (int ls = 0; ls < 3; ++ls)
 259                 for (int lw = 0; lw < 2; ++lw) {
 260                         int const index = lw + (ls << 1) + (c << 6);
 261                         LineGCCache::iterator it = lineGCcache.find(index);
 262                         if (it != lineGCcache.end()) {
 263                                 gc = it->second;
 264                                 XFreeGC(display, gc);
 265                                 lineGCcache.erase(it);
 266                                 getGCLinepars(Painter::line_style(ls),
 267                                               Painter::line_width(lw), c);
 268                         }
 269                 }
 270 }
 271
 272
 273 //
 274 boost::scoped_ptr<LyXColorHandler> lyxColorHandler;
 275
 276 } // namespace frontend
 277 } // namespace lyx