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