Fl_Cairo.cxx

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//
// "$Id: Fl_Cairo.cxx 8198 2011-01-06 10:24:58Z manolo $"
//
// Main header file for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2010 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 on the following page:
//
//     http://www.fltk.org/str.php
//

#include <config.h>

#ifdef FLTK_HAVE_CAIRO
#include <FL/Fl.H>
#include <FL/x.H>
#include <FL/Fl_Window.H>
#ifdef __APPLE__
#include <Carbon/Carbon.h>
#endif

// static Fl module initialization :
Fl_Cairo_State Fl::cairo_state_;        


// Fl cairo features implementation

// Fl_Cairo_State class impl

void  Fl_Cairo_State::autolink(bool b)  {
#ifdef FLTK_USE_CAIRO
  autolink_ = b;
#else
  Fl::fatal("In Fl::autolink(bool) : Cairo autolink() feature is only "
           "available with the enable-cairoext configure option, now quitting.");
#endif
}

cairo_t * Fl::cairo_make_current(Fl_Window* wi) {
    if (!wi) return NULL; // Precondition
    
    if (fl_gc==0) { // means remove current cc
        Fl::cairo_cc(0); // destroy any previous cc
        cairo_state_.window(0);
        return 0;
    }

    // don't re-create a context if it's the same gc/window couple
    if (fl_gc==Fl::cairo_state_.gc() && fl_xid(wi) == (Window) Fl::cairo_state_.window())
        return Fl::cairo_cc();

    cairo_state_.window(wi);

#if defined(USE_X11)
    return Fl::cairo_make_current(0, wi->w(), wi->h());
#else
    return Fl::cairo_make_current(fl_gc, wi->w(), wi->h());
#endif
}

/* 
    Creates transparently a cairo_surface_t object.
    gc is an HDC context in  WIN32, a CGContext* in Quartz, a display on X11
 */
static cairo_surface_t * cairo_create_surface(void * gc, int W, int H) {
# if defined(USE_X11)
    return cairo_xlib_surface_create(fl_display, fl_window, fl_visual->visual, W, H);
# elif   defined(WIN32)
    return cairo_win32_surface_create((HDC) gc);
# elif defined(__APPLE_QUARTZ__)
    return cairo_quartz_surface_create_for_cg_context((CGContext*) gc, W, H);
# else
#  error Cairo is not supported under this platform.
# endif
}

cairo_t * Fl::cairo_make_current(void *gc) {
    int W=0,H=0;
#if defined(USE_X11)
    //FIXME X11 get W,H
    // gc will be the window handle here
# warning FIXME get W,H for cairo_make_current(void*)
#elif defined(__APPLE_QUARTZ__) 
    if (fl_window) {
      Rect portRect; 
      GetPortBounds(GetWindowPort( Fl_X::i(Fl_Window::current())->window_ref() ), &portRect);
      W = portRect.right-portRect.left;
      H = portRect.bottom-portRect.top;
    } 
    else {
      W = CGBitmapContextGetHeight(fl_gc);
      H = CGBitmapContextGetHeight(fl_gc);
    }
#elif defined(WIN32)
    // we don't need any W,H for WIN32
#else
# error Cairo is not supported under this platform.
#endif
    if (!gc) {
        Fl::cairo_cc(0);
        cairo_state_.gc(0); // keep track for next time
        return 0;
    }
    if (gc==Fl::cairo_state_.gc() && fl_window== (Window) Fl::cairo_state_.window())
        return Fl::cairo_cc();
    cairo_state_.gc(fl_gc); // keep track for next time
    cairo_surface_t * s = cairo_create_surface(gc, W, H);
    cairo_t * c = cairo_create(s);
    cairo_surface_destroy(s);
    Fl::cairo_cc(c);
    return c;
}

cairo_t * Fl::cairo_make_current(void *gc, int W, int H) {
  cairo_surface_t * s = cairo_create_surface(gc, W, H);
    cairo_t * c = cairo_create(s);
    cairo_surface_destroy(s);
    Fl::cairo_cc(c);
    return c;
}
#else
// just don't leave the libfltk_cairo lib empty to avoid warnings
#include <FL/Fl_Export.H>
FL_EXPORT int fltk_cairo_dummy() { return 1;}
#endif // FLTK_HAVE_CAIRO

//
// End of "$Id: Fl_Cairo.cxx 8198 2011-01-06 10:24:58Z manolo $" .
//