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