//
// "$Id: Fl_visual.cpp 508 2002-12-20 20:11:31Z laza2000 $"
//
// Visual support for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-1999 by Bill Spitzak and others.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems to "fltk-bugs@easysw.com".
//

// Set the default visual according to passed switches:

#include <config.h>

#include <efltk/Fl.h>
#include <efltk/x.h>

#ifdef _WIN32
int Fl::visual(int flags)
{
    if (flags & FL_DOUBLE) return 0;
    int ret = 1;
    HDC screen = GetDC(0);
    if ((!(flags & FL_INDEX) && GetDeviceCaps(screen, BITSPIXEL) <= 8) ||
        ((flags & FL_RGB8) && GetDeviceCaps(screen, BITSPIXEL)<24)) ret = 0;
    ReleaseDC(0, screen);
    return ret;
}


#else

#if USE_XDBE
#include <X11/extensions/Xdbe.h>
#endif

static int test_visual(XVisualInfo& v, int flags)
{
    if (v.screen != fl_screen) return 0;
    #if USE_COLORMAP
    if (!(flags & FL_INDEX))
    {
        if (v.c_class != StaticColor && v.c_class != TrueColor) return 0;
                                 // fltk will work better in colormap mode
        if (v.depth <= 8) return 0;
    }
    if (flags & FL_RGB8)
    {
        if (v.depth < 24) return 0;
    }
    // for now, fltk does not like colormaps of more than 8 bits:
    if ((v.c_class&1) && v.depth > 8) return 0;
    #else
    // simpler if we can't use colormapped visuals at all:
    if (v.c_class != StaticColor && v.c_class != TrueColor) return 0;
    #endif
    #if USE_XDBE
    if (flags & FL_DOUBLE)
    {
        static XdbeScreenVisualInfo *xdbejunk;
        if (!xdbejunk)
        {
            int event_base, error_base;
            if (!XdbeQueryExtension(fl_display, &event_base, &error_base)) return 0;
            Drawable root = RootWindow(fl_display,fl_screen);
            int numscreens = 1;
            xdbejunk = XdbeGetVisualInfo(fl_display,&root,&numscreens);
            if (!xdbejunk) return 0;
        }
        for (int j = 0; ; j++)
        {
            if (j >= xdbejunk->count) return 0;
            if (xdbejunk->visinfo[j].visual == v.visualid) break;
        }
    }
    #endif
    return 1;
}


int Fl::visual(int flags)
{
    #if USE_XDBE == 0
    if (flags & FL_DOUBLE) return 0;
    #endif
    fl_open_display();
    // always use default if possible:
    if (test_visual(*fl_visual, flags)) return 1;
    // get all the visuals:
    XVisualInfo vTemplate;
    int num;
    XVisualInfo *visualList = XGetVisualInfo(fl_display, 0, &vTemplate, &num);
    // find all matches, use the one with greatest depth:
    XVisualInfo *found = 0;
    for (int i=0; i<num; i++) if (test_visual(visualList[i], flags))
    {
        if (!found || found->depth < visualList[i].depth)
            found = &visualList[i];
    }
    if (!found) {XFree((void*)visualList); return 0;}
    fl_visual = found;
    fl_colormap = XCreateColormap(fl_display, RootWindow(fl_display,fl_screen),
        fl_visual->visual, AllocNone);
    return 1;
}
#endif

//
// End of "$Id: Fl_visual.cpp 508 2002-12-20 20:11:31Z laza2000 $".
//
