//// "$Id: Fl_Gl_Overlay.cxx,v 1.1.1.1 2003/08/07 21:18:40 jasonk Exp $"//// OpenGL overlay code 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".//#include <config.h>#if HAVE_GL#include <FL/Fl.H>#include <FL/Fl_Gl_Window.H>#include <FL/x.H>#include "Fl_Gl_Choice.H"#include <stdlib.h>#if HAVE_GL_OVERLAY#ifndef WIN32// Methods on Fl_Gl_Window that create an overlay window.  Because// many programs don't need the overlay, this is seperated into this// source file so it is not linked in if not used.// Under X this is done by creating another window, of class _Fl_Gl_Overlay// which is a subclass of Fl_Gl_Window except it uses the overlay planes.// A pointer to this is stored in the "overlay" pointer of the Fl_Gl_Window.// Under win32 another GLX context is created to draw into the overlay// and it is stored in into the "overlay" pointer.// In both cases if overlay hardware is unavailable, the overlay is// "faked" by drawing into the main layers.  This is indicated by// setting overlay == this.extern XVisualInfo *fl_find_overlay_visual();extern XVisualInfo *fl_overlay_visual;extern Colormap fl_overlay_colormap;extern unsigned long fl_transparent_pixel;static Fl_Gl_Choice overlay_choice;extern uchar fl_overlay;class _Fl_Gl_Overlay : public Fl_Gl_Window {  void draw();public:  void show();  _Fl_Gl_Overlay(int x, int y, int w, int h) :    Fl_Gl_Window(x,y,w,h) {    overlay_choice.vis = fl_overlay_visual;    overlay_choice.colormap = fl_overlay_colormap;    overlay_choice.r = 0;    overlay_choice.d = 0;    overlay_choice.o = 1;    g = &overlay_choice;    set_flag(INACTIVE);  }};void _Fl_Gl_Overlay::draw() {  if (damage() != FL_DAMAGE_EXPOSE) glClear(GL_COLOR_BUFFER_BIT);  Fl_Gl_Window *w = (Fl_Gl_Window *)parent();  uchar save_valid = w->valid_;  w->valid_ = valid_;  fl_overlay = 1;  w->draw_overlay();  fl_overlay = 0;  valid_ = w->valid_;  w->valid_ = save_valid;}void _Fl_Gl_Overlay::show() {  if (shown()) {Fl_Gl_Window::show(); return;}  fl_background_pixel = int(fl_transparent_pixel);  Fl_Gl_Window::show();  fl_background_pixel = -1;  // find the outermost window to tell wm about the colormap:  Fl_Window *w = window();  for (;;) {Fl_Window *w1 = w->window(); if (!w1) break; w = w1;}  XSetWMColormapWindows(fl_display, fl_xid(w), &(Fl_X::i(this)->xid), 1);}int Fl_Gl_Window::can_do_overlay() {  return fl_find_overlay_visual() != 0;}#else // WIN32:static int no_overlay_hardware;int Fl_Gl_Window::can_do_overlay() {  if (no_overlay_hardware) return 0;  // need to write a test here...  return 1;}#endif#elseint Fl_Gl_Window::can_do_overlay() {return 0;}#endifvoid Fl_Gl_Window::make_overlay() {  if (!overlay) {#if HAVE_GL_OVERLAY#ifdef WIN32    if (!no_overlay_hardware) {      HDC hdc = fl_private_dc(this, mode_,&g);      GLXContext context = wglCreateLayerContext(hdc, 1);      if (!context) { // no overlay hardware	no_overlay_hardware = 1;      } else {	// copy all colors except #0 into the overlay palette:	COLORREF pcr[256];	for (int i = 0; i < 256; i++) {	  uchar r,g,b; Fl::get_color((Fl_Color)i,r,g,b);	  pcr[i] = RGB(r,g,b);	}	wglSetLayerPaletteEntries(hdc, 1, 1, 255, pcr+1);	wglRealizeLayerPalette(hdc, 1, TRUE);	if (fl_first_context) wglShareLists(fl_first_context, context);	else fl_first_context = context;	overlay = context;	valid(0);	return;      }    }#else    if (can_do_overlay()) {      _Fl_Gl_Overlay* o = new _Fl_Gl_Overlay(0,0,w(),h());      overlay = o;      add_resizable(*o);      o->show();      return;    }#endif#endif    overlay = this; // fake the overlay  }}void Fl_Gl_Window::redraw_overlay() {  if (!shown()) return;  make_overlay();#ifndef WIN32  if (overlay != this)    ((Fl_Gl_Window*)overlay)->redraw();  else#endif    damage(FL_DAMAGE_OVERLAY);}void Fl_Gl_Window::make_overlay_current() {  make_overlay();#if HAVE_GL_OVERLAY  if (overlay != this) {#ifdef WIN32    fl_set_gl_context(this, (GLXContext)overlay);#else    ((Fl_Gl_Window*)overlay)->make_current();#endif  } else#endif    glDrawBuffer(GL_FRONT);}void Fl_Gl_Window::hide_overlay() {#if HAVE_GL_OVERLAY#ifdef WIN32  // nothing needs to be done?  Or should it be erased?#else  if (overlay && overlay!=this) ((Fl_Gl_Window*)overlay)->hide();#endif#endif}#endif//// End of "$Id: Fl_Gl_Overlay.cxx,v 1.1.1.1 2003/08/07 21:18:40 jasonk Exp $".//