//
// "$Id: Fl_own_colormap.cxx 11757 2016-05-28 15:39:05Z greg.ercolano $"
//
// Private colormap support for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2010 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file.  If this
// file is missing or damaged, see the license at:
//
//     http://www.fltk.org/COPYING.php
//
// Please report all bugs and problems on the following page:
//
//     http://www.fltk.org/str.php
//

// Using the default system colormap can be a bad idea on PseudoColor
// visuals, since typically every application uses the default colormap and
// you can run out of colormap entries easily.
//
// The solution is to always create a new colormap on PseudoColor displays
// and copy the first 16 colors from the default colormap so that we won't
// get huge color changes when switching windows.

#include <config.h>
#include <FL/Fl.H>
#include <FL/x.H>

/** \fn Fl::own_colormap()
    Makes FLTK use its <a href="fltk-colormap.png">own colormap</a>. This may make FLTK display better
    and will reduce conflicts with other programs that want lots of colors.
    However the colors may flash as you move the cursor between windows.
    
    <P>This does nothing if the current visual is not colormapped.
*/
#ifdef WIN32
// There is probably something relevant to do on MSWindows 8-bit displays
// but I don't know what it is

void Fl::own_colormap() {}

#elif defined(__APPLE__)
// MacOS X always provides a TrueColor interface...

void Fl::own_colormap() {}
#else
// X version

void Fl::own_colormap() {
  fl_open_display();
#if USE_COLORMAP
  switch (fl_visual->c_class) {
  case GrayScale :
  case PseudoColor :
  case DirectColor :
    break;
  default:
    return; // don't do anything for non-colormapped visuals
  }
  int i;
  XColor colors[16];
  // Get the first 16 colors from the default colormap...
  for (i = 0; i < 16; i ++) colors[i].pixel = i;
  XQueryColors(fl_display, fl_colormap, colors, 16);
  // Create a new colormap...
  fl_colormap = XCreateColormap(fl_display,
				RootWindow(fl_display,fl_screen),
				fl_visual->visual, AllocNone);
  // Copy those first 16 colors to our own colormap:
  for (i = 0; i < 16; i ++)
    XAllocColor(fl_display, fl_colormap, colors + i);
#endif
}

#endif

//
// End of "$Id: Fl_own_colormap.cxx 11757 2016-05-28 15:39:05Z greg.ercolano $".
//
