ref: 9eaba52cafcac7c2f3bfc72d7be1f15893196be1
dir: /DoConfig/fltk/src/Fl_Gl_Overlay.cxx/
//
// "$Id$"
//
// OpenGL overlay code 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
//
#include <config.h>
#if HAVE_GL
#include <FL/Fl.H>
#include <FL/x.H>
#include "Fl_Gl_Choice.H"
#include <FL/Fl_Gl_Window.H>
#include <stdlib.h>
#if !HAVE_GL_OVERLAY
int Fl_Gl_Window::can_do_overlay() {return 0;}
void Fl_Gl_Window::make_overlay() {overlay = this;}
#else
// Methods on Fl_Gl_Window that create an overlay window. Because
// many programs don't need the overlay, this is separated 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 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.
#ifndef WIN32
////////////////////////////////////////////////////////////////
// X version
extern XVisualInfo *fl_find_overlay_visual();
extern XVisualInfo *fl_overlay_visual;
extern Colormap fl_overlay_colormap;
extern unsigned long fl_transparent_pixel;
extern uchar fl_overlay;
class _Fl_Gl_Overlay : public Fl_Gl_Window {
void flush();
void draw();
public:
void show();
_Fl_Gl_Overlay(int x, int y, int w, int h) :
Fl_Gl_Window(x,y,w,h) {
set_flag(INACTIVE);
}
};
void _Fl_Gl_Overlay::flush() {
make_current();
#ifdef BOXX_BUGS
// The BoXX overlay is broken and you must not call swap-buffers. This
// code will make it work, but we lose because machines that do support
// double-buffered overlays will blink when they don't have to
glDrawBuffer(GL_FRONT);
draw();
#else
draw();
swap_buffers();
#endif
glFlush();
valid(1);
}
void _Fl_Gl_Overlay::draw() {
if (!valid()) glClearIndex((GLfloat)fl_transparent_pixel);
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_background_pixel = int(fl_transparent_pixel);
Fl_X::make_xid(this, fl_overlay_visual, fl_overlay_colormap);
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);
context(fl_create_gl_context(fl_overlay_visual), 1);
valid(0);
}
Fl_Gl_Window::show();
}
int Fl_Gl_Window::can_do_overlay() {
return fl_find_overlay_visual() != 0;
}
void Fl_Gl_Window::make_overlay() {
if (overlay) return;
if (can_do_overlay()) {
_Fl_Gl_Overlay* o = new _Fl_Gl_Overlay(0,0,w(),h());
overlay = o;
add(*o);
o->show();
} else {
overlay = this; // fake the overlay
}
}
#else
////////////////////////////////////////////////////////////////
// WIN32 version:
//static COLORREF *palette;
extern int fl_overlay_depth;
void Fl_Gl_Window::make_overlay() {
if (overlay) return;
GLContext context = fl_create_gl_context(this, g, 1);
if (!context) {overlay = this; return;} // fake the overlay
HDC hdc = Fl_X::i(this)->private_dc;
overlay = context;
LAYERPLANEDESCRIPTOR pfd;
wglDescribeLayerPlane(hdc, g->pixelformat, 1, sizeof(pfd), &pfd);
if (!pfd.iPixelType) {
; // full-color overlay
} else {
fl_overlay_depth = pfd.cColorBits; // used by gl_color()
if (fl_overlay_depth > 8) fl_overlay_depth = 8;
COLORREF palette[256];
int n = (1<<fl_overlay_depth)-1;
// copy all colors except #0 into the overlay palette:
for (int i = 0; i <= n; i++) {
uchar r,g,b; Fl::get_color((Fl_Color)i,r,g,b);
palette[i] = RGB(r,g,b);
}
// always provide black & white in the last 2 pixels:
if (fl_overlay_depth < 8) {
palette[n-1] = RGB(0,0,0);
palette[n] = RGB(255,255,255);
}
// and use it:
wglSetLayerPaletteEntries(hdc, 1, 1, n, palette+1);
wglRealizeLayerPalette(hdc, 1, TRUE);
}
valid(0);
return;
}
int Fl_Gl_Window::can_do_overlay() {
if (!g) {
g = Fl_Gl_Choice::find(mode_,alist);
if (!g) return 0;
}
return (g->pfd.bReserved & 15) != 0;
}
////////////////////////////////////////////////////////////////
#endif
#endif
void Fl_Gl_Window::redraw_overlay() {
if (!shown()) return;
make_overlay();
#ifdef __APPLE__
redraw();
#else
#ifndef WIN32
if (overlay != this)
((Fl_Gl_Window*)overlay)->redraw();
else
#endif
damage(FL_DAMAGE_OVERLAY);
#endif
}
void Fl_Gl_Window::make_overlay_current() {
make_overlay();
#ifdef __APPLE__
// this is not very useful, but unfortunately, Apple decided
// that front buffer drawing can no longer (OS X 10.4) be
// supported on their platforms.
make_current();
#else
#if HAVE_GL_OVERLAY
if (overlay != this) {
#ifdef WIN32
fl_set_gl_context(this, (GLContext)overlay);
// if (fl_overlay_depth)
// wglRealizeLayerPalette(Fl_X::i(this)->private_dc, 1, TRUE);
#else
((Fl_Gl_Window*)overlay)->make_current();
#endif
} else
#endif
glDrawBuffer(GL_FRONT);
#endif
}
/** Hides the window if it is not this window, does nothing in WIN32. */
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 "$Id$".
//