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
  14 #include "ColorHandler.h"
  15 #include "LColor.h"
  16 #include "gettext.h"
  17 #include "debug.h"
  18
  19 #include <boost/scoped_array.hpp>
  20 #include "support/tostr.h"
  21 #include "support/lstrings.h"
  22
  23 #include <cmath>
  24
  25 using namespace lyx::support;
  26
  27 #ifndef CXX_GLOBAL_CSTD
  28 using std::pow;
  29 #endif
  30
  31 using std::endl;
  32
  33 #include "lyx_forms.h"
  34
  35 namespace {
  36
  37         string tostr(XColor const & col)
  38         {
  39                 return bformat("(%1$s,%2$s,%3$s)",
  40                         ::tostr(col.red), ::tostr(col.green), ::tostr(col.blue));
  41         }
  42
  43 }
  44
  45
  46 LyXColorHandler::LyXColorHandler()
  47 {
  48         display = fl_get_display();
  49         drawable = XCreatePixmap(display,
  50                                  RootWindow(display, fl_screen),
  51                                  10, 10, fl_get_visual_depth());
  52
  53         colormap = fl_state[fl_get_vclass()].colormap;
  54         // Clear the GC cache
  55         for (int i = 0; i <= LColor::ignore; ++i) {
  56                 colorGCcache[i] = 0;
  57         }
  58 }
  59
  60
  61 LyXColorHandler::~LyXColorHandler()
  62 {
  63         // Release all the registered GCs
  64         for (int i = 0; i <= LColor::ignore; ++i) {
  65                 if (colorGCcache[i] != 0) {
  66                         XFreeGC(display, colorGCcache[i]);
  67                 }
  68         }
  69         // Iterate over the line cache and Free the GCs
  70         for (LineGCCache::iterator lit = lineGCcache.begin();
  71              lit != lineGCcache.end(); ++lit) {
  72                 XFreeGC(display, lit->second);
  73         }
  74 }
  75
  76
  77 unsigned long LyXColorHandler::colorPixel(LColor::color c)
  78 {
  79         XGCValues val;
  80         XGetGCValues(display, getGCForeground(c), GCForeground, &val);
  81         return val.foreground;
  82 }
  83
  84
  85 // Gets GC according to color
  86 // Uses caching
  87 GC LyXColorHandler::getGCForeground(LColor::color c)
  88 {
  89         if (colorGCcache[c] != 0)
  90                 return colorGCcache[c];
  91
  92         XColor xcol;
  93         XColor ccol;
  94         string const s = lcolor.getX11Name(c);
  95         XGCValues val;
  96
  97         // Look up the RGB values for the color, and an approximate
  98         // color that we can hope to get on this display.
  99         if (XLookupColor(display, colormap, s.c_str(), &xcol, &ccol) == 0) {
 100                 lyxerr << bformat(
 101                         _("LyX: Unknown X11 color %1$s for %2$s\n"
 102                           "     Using black instead, sorry!"),
 103                         s, lcolor.getGUIName(c)) << endl;
 104                 unsigned long bla = BlackPixel(display,
 105                                                DefaultScreen(display));
 106                 val.foreground = bla;
 107         // Try the exact RGB values first, then the approximate.
 108         } else if (XAllocColor(display, colormap, &xcol) != 0) {
 109                 if (lyxerr.debugging(Debug::GUI)) {
 110                         lyxerr << bformat(_("LyX: X11 color %1$s allocated for %2$s"),
 111                                 s, lcolor.getGUIName(c)) << endl;
 112                 }
 113                 val.foreground = xcol.pixel;
 114         } else if (XAllocColor(display, colormap, &ccol)) {
 115                 lyxerr << bformat(
 116                         _("LyX: Using approximated X11 color %1$s allocated for %2$s"),
 117                         s, lcolor.getGUIName(c)) << endl;
 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' for %2$s with (r,g,b)=%3$s.\n"),
 159                         s, lcolor.getGUIName(c), 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]), tostr(closest_pixel)) << endl;
 165
 166                 val.foreground = cmap[closest_pixel].pixel;
 167         }
 168
 169         val.function = GXcopy;
 170         return colorGCcache[c] = XCreateGC(display, drawable,
 171                                            GCForeground | GCFunction, &val);
 172 }
 173
 174
 175 // Gets GC for line
 176 GC LyXColorHandler::getGCLinepars(Painter::line_style ls,
 177                                   Painter::line_width lw, LColor::color c)
 178 {
 179         //if (lyxerr.debugging()) {
 180         //      lyxerr << "Painter drawable: " << drawable() << endl;
 181         //}
 182
 183         int index = lw + (ls << 1) + (c << 6);
 184
 185         LineGCCache::iterator it = lineGCcache.find(index);
 186         if (it != lineGCcache.end())
 187                 return it->second;
 188
 189         XGCValues val;
 190         XGetGCValues(display, getGCForeground(c), GCForeground, &val);
 191
 192         switch (lw) {
 193         case Painter::line_thin:
 194                 val.line_width = 0;
 195                 break;
 196         case Painter::line_thick:
 197                 val.line_width = 2;
 198                 break;
 199         }
 200
 201         switch (ls) {
 202         case Painter::line_solid:
 203                 val.line_style = LineSolid;
 204                 break;
 205         case Painter::line_onoffdash:
 206                 val.line_style = LineOnOffDash;
 207                 break;
 208         }
 209
 210
 211         val.cap_style = CapRound;
 212         val.join_style = JoinRound;
 213         val.function = GXcopy;
 214
 215         return lineGCcache[index] =
 216                 XCreateGC(display, drawable,
 217                           GCForeground | GCLineStyle | GCLineWidth |
 218                           GCCapStyle | GCJoinStyle | GCFunction, &val);
 219 }
 220
 221
 222 // update GC cache after color redefinition
 223 void LyXColorHandler::updateColor (LColor::color c)
 224 {
 225         // color GC cache
 226         GC gc = colorGCcache[c];
 227         if (gc != 0) {
 228                 XFreeGC(display, gc);
 229                 colorGCcache[c] = NULL;
 230                 getGCForeground(c);
 231         }
 232
 233         // line GC cache
 234
 235         for (int ls = 0; ls < 3; ++ls)
 236                 for (int lw = 0; lw < 2; ++lw) {
 237                         int const index = lw + (ls << 1) + (c << 6);
 238                         LineGCCache::iterator it = lineGCcache.find(index);
 239                         if (it != lineGCcache.end()) {
 240                                 gc = it->second;
 241                                 XFreeGC(display, gc);
 242                                 lineGCcache.erase(it);
 243                                 getGCLinepars(Painter::line_style(ls),
 244                                               Painter::line_width(lw), c);
 245                         }
 246                 }
 247 }
 248
 249
 250 //
 251 boost::scoped_ptr<LyXColorHandler> lyxColorHandler;