src/ColorHandler.C

   1 // -*- C++ -*-
   2 /* This file is part of
   3  * ======================================================
   4  *
   5  *           LyX, The Document Processor
   6  *
   7  *          Copyright 1998-2000 The LyX Team
   8  *
   9  *======================================================*/
  10
  11 #include <config.h>
  12
  13 #ifdef __GNUG__
  14 #pragma implementation
  15 #endif
  16
  17 #include <cmath>
  18
  19 #include FORMS_H_LOCATION
  20 #include "debug.h"
  21
  22 #include "ColorHandler.h"
  23 #include "gettext.h"
  24
  25 using std::endl;
  26
  27 LyXColorHandler::LyXColorHandler()
  28 {
  29         display = fl_display;
  30         drawable = XCreatePixmap(display, fl_root, 10, 10,
  31                                  fl_get_visual_depth());
  32
  33         colormap = fl_state[fl_get_vclass()].colormap;
  34         // Clear the GC cache
  35         for (int i = 0; i <= LColor::ignore; ++i) {
  36                 colorGCcache[i] = 0;
  37         }
  38 }
  39
  40
  41 LyXColorHandler::~LyXColorHandler()
  42 {
  43         // Release all the registered GCs
  44         for (int i = 0; i <= LColor::ignore; ++i) {
  45                 if (colorGCcache[i] != 0) {
  46                         XFreeGC(display, colorGCcache[i]);
  47                 }
  48         }
  49         // Iterate over the line cache and Free the GCs
  50         for (LineGCCache::iterator lit = lineGCcache.begin();
  51              lit != lineGCcache.end(); ++lit) {
  52                 XFreeGC(display, (*lit).second);
  53         }
  54 }
  55
  56
  57 unsigned long LyXColorHandler::colorPixel(LColor::color c)
  58 {
  59         XGCValues val;
  60         XGetGCValues(display, getGCForeground(c), GCForeground, &val);
  61         return val.foreground;
  62 }
  63
  64
  65 // Gets GC according to color
  66 // Uses caching
  67 GC LyXColorHandler::getGCForeground(LColor::color c)
  68 {
  69         //if (lyxerr.debugging()) {
  70         //      lyxerr << "Painter drawable: " << drawable() << endl;
  71         //}
  72
  73         if (colorGCcache[c] != 0) return colorGCcache[c];
  74
  75         XColor xcol, ccol;
  76         string s = lcolor.getX11Name(c);
  77         XGCValues val;
  78
  79         // Look up the RGB values for the color, and an approximate
  80         // color that we can hope to get on this display.
  81         if (XLookupColor(display, colormap, s.c_str(), &xcol, &ccol) == 0) {
  82                 lyxerr << _("LyX: Unknown X11 color ") << s
  83                        << _(" for ") << lcolor.getGUIName(c) << '\n'
  84                        << _("     Using black instead, sorry!.") << endl;
  85                 unsigned long bla = BlackPixel(display,
  86                                                DefaultScreen(display));
  87                 val.foreground = bla;
  88         // Try the exact RGB values first, then the approximate.
  89         } else if (XAllocColor(display, colormap, &xcol) != 0) {
  90                 if (lyxerr.debugging()) {
  91                         lyxerr << _("LyX: X11 color ") << s
  92                                << _(" allocated for ")
  93                                << lcolor.getGUIName(c) << endl;
  94                 }
  95                 val.foreground = xcol.pixel;
  96         } else if (XAllocColor(display, colormap, &ccol)) {
  97                 lyxerr << _("LyX: Using approximated X11 color ") << s
  98                        << _(" allocated for ")
  99                        << lcolor.getGUIName(c) << endl;
 100                 val.foreground = xcol.pixel;
 101         } else {
 102                 // Here we are traversing the current colormap to find
 103                 // the color closest to the one we want.
 104                 Visual * vi = DefaultVisual(display, DefaultScreen(display));
 105
 106                 XColor * cmap = new XColor[vi->map_entries];
 107
 108                 for(int i = 0; i < vi->map_entries; ++i) {
 109                         cmap[i].pixel = i;
 110                 }
 111                 XQueryColors(display, colormap, cmap, vi->map_entries);
 112
 113                 // Walk through the cmap and look for close colors.
 114                 int closest_pixel = 0;
 115                 double closest_distance = 1e20; // we want to minimize this
 116                 double distance = 0;
 117                 for(int t = 0; t < vi->map_entries; ++t) {
 118                         // The Euclidean distance between two points in
 119                         // a three-dimensional space, the RGB color-cube,
 120                         // is used as the distance measurement between two
 121                         // colors.
 122
 123                         // Since square-root is monotonous, we don't have to
 124                         // take the square-root to find the minimum, and thus
 125                         // we use the squared distance instead to be faster.
 126
 127                         // If we want to get fancy, we could convert the RGB
 128                         // coordinates to a different color-cube, maybe HSV,
 129                         // but the RGB cube seems to work great.  (Asger)
 130                         distance = pow(cmap[t].red   - xcol.red,   2.0) +
 131                                    pow(cmap[t].green - xcol.green, 2.0) +
 132                                    pow(cmap[t].blue  - xcol.blue,  2.0);
 133                         if (distance < closest_distance) {
 134                                 closest_distance = distance;
 135                                 closest_pixel = t;
 136                         }
 137                 }
 138                 lyxerr << _("LyX: Couldn't allocate '") << s
 139                        << _("' for ") << lcolor.getGUIName(c)
 140                        << _(" with (r,g,b)=(")
 141                        << xcol.red << "," << xcol.green << ","
 142                        << xcol.blue << ").\n"
 143                        << _("     Using closest allocated "
 144                             "color with (r,g,b)=(")
 145                        << cmap[closest_pixel].red << ","
 146                        << cmap[closest_pixel].green << ","
 147                        << cmap[closest_pixel].blue << _(") instead.\n")
 148                        << _("Pixel [") << closest_pixel << _("] is used.")
 149                        << endl;
 150                 val.foreground = cmap[closest_pixel].pixel;
 151                 delete[] cmap;
 152         }
 153
 154         val.function = GXcopy;
 155         return colorGCcache[c] = XCreateGC(display, drawable,
 156                                     GCForeground | GCFunction, &val);
 157 }
 158
 159
 160 // Gets GC for line
 161 GC LyXColorHandler::getGCLinepars(PainterBase::line_style ls,
 162                           PainterBase::line_width lw, LColor::color c)
 163 {
 164         //if (lyxerr.debugging()) {
 165         //      lyxerr << "Painter drawable: " << drawable() << endl;
 166         //}
 167
 168         int index = lw + (ls << 1) + (c << 3);
 169
 170         if (lineGCcache.find(index) != lineGCcache.end())
 171                 return lineGCcache[index];
 172
 173         XGCValues val;
 174         XGetGCValues(display, getGCForeground(c), GCForeground, &val);
 175
 176         switch (lw) {
 177         case PainterBase::line_thin:    val.line_width = 0; break;
 178         case PainterBase::line_thick:   val.line_width = 2; break;
 179         }
 180
 181         switch (ls) {
 182         case PainterBase::line_solid:   val.line_style = LineSolid; break;
 183         case PainterBase::line_onoffdash:       val.line_style = LineOnOffDash; break;
 184         case PainterBase::line_doubledash:      val.line_style = LineDoubleDash; break;
 185         }
 186
 187
 188         val.cap_style = CapRound;
 189         val.join_style = JoinRound;
 190         val.function = GXcopy;
 191
 192         return lineGCcache[index] =
 193                 XCreateGC(display, drawable,
 194                           GCForeground | GCLineStyle | GCLineWidth |
 195                           GCCapStyle | GCJoinStyle | GCFunction, &val);
 196 }
 197
 198 //
 199 LyXColorHandler * lyxColorHandler;