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Fix STR 3458: "GLUT compatibility mode segfaults" 

... "when there's no current window".

Silently ignore GLUT function calls that need a current window if the
current window is NULL, return 0 from functions that return an 'int'.

Check if window is shown in Fl_X11_Gl_Window_Driver::swap_buffers().
This would issue "XRequest.nnn: GLXBadDrawable 0x0" on X11 otherwise.

Note: the chosen implementation to ignore GLUT calls silently appears
to be compatible with GLUT (3.7) whereas FreeGLUT 3.0 would issue error
messages and exit. The latter could be implemented as well but would
be much more work.
This commit is contained in:
Albrecht Schlosser 2023-10-07 17:14:11 +02:00
parent f6690a9742
commit 1fd6f0dd3a
6 changed files with 351 additions and 87 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

225
FL/glut.H
View File

@ -26,6 +26,17 @@
// Commented out lines indicate parts of GLUT that are not emulated.
// Notes: as pointed out in STR #3458 the current GLUT window,
// i.e. the global static variable 'glut_window' can be NULL ...
// (a) if not (yet) initialized
// (b) if the current GLUT window is deleted at any time.
// The FLTK implementation silently ignores function calls if the current
// window is NULL to avoid dereferencing a NULL pointer. This is obviously
// compatible with GLUT version 3.7 according to comment #5 on STR #3458.
// According to the same comment FreeGLUT 3.0 would issue an error message
// and quit.
// Albrecht-S, Oct 2023
#ifndef _FL_glut_H_
# define _FL_glut_H_
@ -81,18 +92,18 @@ FL_EXPORT void glutInit(int *argcp, char **argv); // creates first window
FL_EXPORT void glutInitDisplayMode(unsigned int mode);
// the FL_ symbols have the same value as the GLUT ones:
# define GLUT_RGB FL_RGB
# define GLUT_RGBA FL_RGB
# define GLUT_INDEX FL_INDEX
# define GLUT_SINGLE FL_SINGLE
# define GLUT_DOUBLE FL_DOUBLE
# define GLUT_ACCUM FL_ACCUM
# define GLUT_ALPHA FL_ALPHA
# define GLUT_DEPTH FL_DEPTH
# define GLUT_STENCIL FL_STENCIL
# define GLUT_MULTISAMPLE FL_MULTISAMPLE
# define GLUT_STEREO FL_STEREO
// # define GLUT_LUMINANCE 512
# define GLUT_RGB FL_RGB
# define GLUT_RGBA FL_RGB
# define GLUT_INDEX FL_INDEX
# define GLUT_SINGLE FL_SINGLE
# define GLUT_DOUBLE FL_DOUBLE
# define GLUT_ACCUM FL_ACCUM
# define GLUT_ALPHA FL_ALPHA
# define GLUT_DEPTH FL_DEPTH
# define GLUT_STENCIL FL_STENCIL
# define GLUT_MULTISAMPLE FL_MULTISAMPLE
# define GLUT_STEREO FL_STEREO
// # define GLUT_LUMINANCE 512
FL_EXPORT void glutInitWindowPosition(int x, int y);
@ -107,37 +118,62 @@ FL_EXPORT int glutCreateSubWindow(int win, int x, int y, int width, int height);
FL_EXPORT void glutDestroyWindow(int win);
inline void glutPostRedisplay() {glut_window->redraw();}
inline void glutPostRedisplay() {
if (glut_window) glut_window->redraw();
}
FL_EXPORT void glutPostWindowRedisplay(int win);
FL_EXPORT void glutSwapBuffers();
inline int glutGetWindow() {return glut_window->number;}
inline int glutGetWindow() {
return glut_window ? glut_window->number : 0;
}
FL_EXPORT void glutSetWindow(int win);
inline void glutSetWindowTitle(char *t) {glut_window->label(t);}
inline void glutSetWindowTitle(char *t) {
if (glut_window) glut_window->label(t);
}
inline void glutSetIconTitle(char *t) {glut_window->iconlabel(t);}
inline void glutSetIconTitle(char *t) {
if (glut_window) glut_window->iconlabel(t);
}
inline void glutPositionWindow(int x, int y) {glut_window->position(x,y);}
inline void glutPositionWindow(int x, int y) {
if (glut_window) glut_window->position(x,y);
}
inline void glutReshapeWindow(int w, int h) {glut_window->size(w,h);}
inline void glutReshapeWindow(int w, int h) {
if (glut_window) glut_window->size(w,h);
}
inline void glutPopWindow() {glut_window->show();}
inline void glutPopWindow() {
if (glut_window) glut_window->show();
}
inline void glutPushWindow() { /* do nothing */ }
inline void glutIconifyWindow() {glut_window->iconize();}
inline void glutIconifyWindow() {
if (glut_window) glut_window->iconize();
}
inline void glutShowWindow() {glut_window->show();}
inline void glutShowWindow() {
if (glut_window) glut_window->show();
}
inline void glutHideWindow() {glut_window->hide();}
inline void glutHideWindow() {
if (glut_window) glut_window->hide();
}
inline void glutFullScreen() {glut_window->fullscreen();}
inline void glutFullScreen() {
if (glut_window) glut_window->fullscreen();
}
inline void glutSetCursor(Fl_Cursor cursor) {
if (glut_window) glut_window->cursor(cursor);
}
inline void glutSetCursor(Fl_Cursor cursor) {glut_window->cursor(cursor);}
// notice that the numeric values are different than glut:
# define GLUT_CURSOR_RIGHT_ARROW ((Fl_Cursor)2)
# define GLUT_CURSOR_LEFT_ARROW ((Fl_Cursor)67)
@ -165,19 +201,33 @@ inline void glutSetCursor(Fl_Cursor cursor) {glut_window->cursor(cursor);}
inline void glutWarpPointer(int, int) { /* do nothing */ }
inline void glutEstablishOverlay() {glut_window->make_overlay_current();}
inline void glutEstablishOverlay() {
if (glut_window) glut_window->make_overlay_current();
}
inline void glutRemoveOverlay() {glut_window->hide_overlay();}
inline void glutRemoveOverlay() {
if (glut_window) glut_window->hide_overlay();
}
inline void glutUseLayer(GLenum layer) {
layer ? glut_window->make_overlay_current() : glut_window->make_current();}
if (!glut_window)
return;
layer ? glut_window->make_overlay_current() : glut_window->make_current();
}
enum {GLUT_NORMAL, GLUT_OVERLAY};
inline void glutPostOverlayRedisplay() {glut_window->redraw_overlay();}
inline void glutPostOverlayRedisplay() {
if (glut_window) glut_window->redraw_overlay();
}
inline void glutShowOverlay() {glut_window->redraw_overlay();}
inline void glutShowOverlay() {
if (glut_window) glut_window->redraw_overlay();
}
inline void glutHideOverlay() {glut_window->hide_overlay();}
inline void glutHideOverlay() {
if (glut_window) glut_window->hide_overlay();
}
FL_EXPORT int glutCreateMenu(void (*)(int));
@ -197,34 +247,53 @@ FL_EXPORT void glutChangeToSubMenu(int item, char *label, int submenu);
FL_EXPORT void glutRemoveMenuItem(int item);
inline void glutAttachMenu(int b) {glut_window->menu[b] = glut_menu;}
inline void glutAttachMenu(int b) {
if (glut_window) glut_window->menu[b] = glut_menu;
}
inline void glutDetachMenu(int b) {glut_window->menu[b] = 0;}
inline void glutDetachMenu(int b) {
if (glut_window) glut_window->menu[b] = 0;
}
inline void glutDisplayFunc(void (*f)()) {glut_window->display = f;}
inline void glutDisplayFunc(void (*f)()) {
if (glut_window) glut_window->display = f;
}
inline void glutReshapeFunc(void (*f)(int w, int h)) {glut_window->reshape=f;}
inline void glutReshapeFunc(void (*f)(int w, int h)) {
if (glut_window) glut_window->reshape = f;
}
inline void glutKeyboardFunc(void (*f)(uchar key, int x, int y)) {
glut_window->keyboard = f;}
if (glut_window) glut_window->keyboard = f;
}
inline void glutMouseFunc(void (*f)(int b, int state, int x, int y)) {
glut_window->mouse = f;}
if (glut_window) glut_window->mouse = f;
}
# define GLUT_LEFT_BUTTON 0
# define GLUT_MIDDLE_BUTTON 1
# define GLUT_RIGHT_BUTTON 2
# define GLUT_DOWN 0
# define GLUT_UP 1
inline void glutMotionFunc(void (*f)(int x, int y)) {glut_window->motion= f;}
inline void glutMotionFunc(void (*f)(int x, int y)) {
if (glut_window) glut_window->motion = f;
}
inline void glutPassiveMotionFunc(void (*f)(int x, int y)) {
glut_window->passivemotion= f;}
if (glut_window) glut_window->passivemotion = f;
}
inline void glutEntryFunc(void (*f)(int s)) {
if (glut_window) glut_window->entry = f;
}
inline void glutEntryFunc(void (*f)(int s)) {glut_window->entry = f;}
enum {GLUT_LEFT, GLUT_ENTERED};
inline void glutVisibilityFunc(void (*f)(int s)) {glut_window->visibility=f;}
inline void glutVisibilityFunc(void (*f)(int s)) {
if (glut_window) glut_window->visibility = f;
}
enum {GLUT_NOT_VISIBLE, GLUT_VISIBLE};
FL_EXPORT void glutIdleFunc(void (*f)());
@ -241,7 +310,9 @@ inline void glutMenuStatusFunc(void (*f)(int status, int x, int y)) {
enum {GLUT_MENU_NOT_IN_USE, GLUT_MENU_IN_USE};
inline void glutSpecialFunc(void (*f)(int key, int x, int y)) {
glut_window->special = f;}
if (glut_window) glut_window->special = f;
}
# define GLUT_KEY_F1 1
# define GLUT_KEY_F2 2
# define GLUT_KEY_F3 3
@ -265,35 +336,36 @@ inline void glutSpecialFunc(void (*f)(int key, int x, int y)) {
# define GLUT_KEY_END FL_End
# define GLUT_KEY_INSERT FL_Insert
//inline void glutSpaceballMotionFunc(void (*)(int x, int y, int z));
// inline void glutSpaceballMotionFunc(void (*)(int x, int y, int z));
//inline void glutSpaceballRotateFunc(void (*)(int x, int y, int z));
// inline void glutSpaceballRotateFunc(void (*)(int x, int y, int z));
//inline void glutSpaceballButtonFunc(void (*)(int button, int state));
// inline void glutSpaceballButtonFunc(void (*)(int button, int state));
//inline void glutButtonBoxFunc(void (*)(int button, int state));
// inline void glutButtonBoxFunc(void (*)(int button, int state));
//inline void glutDialsFunc(void (*)(int dial, int value));
// inline void glutDialsFunc(void (*)(int dial, int value));
//inline void glutTabletMotionFunc(void (*)(int x, int y));
// inline void glutTabletMotionFunc(void (*)(int x, int y));
//inline void glutTabletButtonFunc(void (*)(int button, int state, int x, int y));
// inline void glutTabletButtonFunc(void (*)(int button, int state, int x, int y));
inline void glutOverlayDisplayFunc(void (*f)()) {
glut_window->overlaydisplay = f;}
if (glut_window) glut_window->overlaydisplay = f;
}
//inline void glutWindowStatusFunc(void (*)(int state));
//enum {GLUT_HIDDEN, GLUT_FULLY_RETAINED, GLUT_PARTIALLY_RETAINED,
// GLUT_FULLY_COVERED};
// inline void glutWindowStatusFunc(void (*)(int state));
// enum {GLUT_HIDDEN, GLUT_FULLY_RETAINED, GLUT_PARTIALLY_RETAINED,
// GLUT_FULLY_COVERED};
//inline void glutSetColor(int, GLfloat red, GLfloat green, GLfloat blue);
// inline void glutSetColor(int, GLfloat red, GLfloat green, GLfloat blue);
//inline GLfloat glutGetColor(int ndx, int component);
//#define GLUT_RED 0
//#define GLUT_GREEN 1
//#define GLUT_BLUE 2
// inline GLfloat glutGetColor(int ndx, int component);
// #define GLUT_RED 0
// #define GLUT_GREEN 1
// #define GLUT_BLUE 2
//inline void glutCopyColormap(int win);
// inline void glutCopyColormap(int win);
// Warning: values are changed from GLUT!
// Also relies on the GL_ symbols having values greater than 100
@ -359,13 +431,16 @@ FL_EXPORT int glutDeviceGet(GLenum type);
# define GLUT_ACTIVE_SHIFT FL_SHIFT
# define GLUT_ACTIVE_CTRL FL_CTRL
# define GLUT_ACTIVE_ALT FL_ALT
inline int glutGetModifiers() {return Fl::event_state() & (GLUT_ACTIVE_SHIFT | GLUT_ACTIVE_CTRL | GLUT_ACTIVE_ALT);}
inline int glutGetModifiers() {
return Fl::event_state() & (GLUT_ACTIVE_SHIFT | GLUT_ACTIVE_CTRL | GLUT_ACTIVE_ALT);
}
FL_EXPORT int glutLayerGet(GLenum);
# define GLUT_OVERLAY_POSSIBLE 800
//#define GLUT_LAYER_IN_USE 801
//#define GLUT_HAS_OVERLAY 802
# define GLUT_TRANSPARENT_INDEX 803
# define GLUT_TRANSPARENT_INDEX 803
# define GLUT_NORMAL_DAMAGED 804
# define GLUT_OVERLAY_DAMAGED 805
@ -375,25 +450,25 @@ typedef void (*GLUTproc)();
FL_EXPORT GLUTproc glutGetProcAddress(const char *procName);
//inline int glutVideoResizeGet(GLenum param);
//#define GLUT_VIDEO_RESIZE_POSSIBLE 900
//#define GLUT_VIDEO_RESIZE_IN_USE 901
//#define GLUT_VIDEO_RESIZE_X_DELTA 902
//#define GLUT_VIDEO_RESIZE_Y_DELTA 903
//#define GLUT_VIDEO_RESIZE_WIDTH_DELTA 904
//#define GLUT_VIDEO_RESIZE_HEIGHT_DELTA 905
//#define GLUT_VIDEO_RESIZE_X 906
//#define GLUT_VIDEO_RESIZE_Y 907
//#define GLUT_VIDEO_RESIZE_WIDTH 908
//#define GLUT_VIDEO_RESIZE_HEIGHT 909
// inline int glutVideoResizeGet(GLenum param);
// #define GLUT_VIDEO_RESIZE_POSSIBLE 900
// #define GLUT_VIDEO_RESIZE_IN_USE 901
// #define GLUT_VIDEO_RESIZE_X_DELTA 902
// #define GLUT_VIDEO_RESIZE_Y_DELTA 903
// #define GLUT_VIDEO_RESIZE_WIDTH_DELTA 904
// #define GLUT_VIDEO_RESIZE_HEIGHT_DELTA 905
// #define GLUT_VIDEO_RESIZE_X 906
// #define GLUT_VIDEO_RESIZE_Y 907
// #define GLUT_VIDEO_RESIZE_WIDTH 908
// #define GLUT_VIDEO_RESIZE_HEIGHT 909
//inline void glutSetupVideoResizing();
// inline void glutSetupVideoResizing();
//inline void glutStopVideoResizing();
// inline void glutStopVideoResizing();
//inline void glutVideoResize(int x, int y, int width, int height);
// inline void glutVideoResize(int x, int y, int width, int height);
//inline void glutVideoPan(int x, int y, int width, int height);
// inline void glutVideoPan(int x, int y, int width, int height);
// Font argument must be a void* for compatibility, so...
/** fltk glut font/size attributes used in the glutXXX functions */

2
src/drivers/X11/Fl_X11_Gl_Window_Driver.cxx
View File

@ -388,6 +388,8 @@ int Fl_X11_Gl_Window_Driver::mode_(int m, const int *a) {
}
void Fl_X11_Gl_Window_Driver::swap_buffers() {
if (!fl_xid(pWindow)) // window not shown
return;
glXSwapBuffers(fl_display, fl_xid(pWindow));
}

26
src/glut_compatibility.cxx
View File

@ -1,7 +1,7 @@
//
// GLUT emulation routines for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2016 by Bill Spitzak and others.
// Copyright 1998-2023 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
@ -14,11 +14,11 @@
// https://www.fltk.org/bugs.php
//
// Emulation of Glut using fltk.
// Emulation of Glut using FLTK.
// GLUT is Copyright (c) Mark J. Kilgard, 1994, 1995, 1996.
// "This program is freely distributable without licensing fees and is
// provided without guarantee or warrantee expressed or implied. This
// "This program is freely distributable without licensing fees and is
// provided without guarantee or warrantee expressed or implied. This
// program is -not- in the public domain."
// Although I have copied the GLUT API, none of my code is based on
@ -35,6 +35,7 @@ static Fl_Glut_Window *windows[MAXWINDOWS+1];
static void (*glut_idle_func)() = 0; // global glut idle function
// The current GLUT window, may be NULL. See also STR #3458.
Fl_Glut_Window *glut_window;
int glut_menu;
void (*glut_menustate_function)(int);
@ -61,7 +62,8 @@ void Fl_Glut_Window::draw() {
}
void glutSwapBuffers() {
if (!indraw) glut_window->swap_buffers();
if (!indraw && glut_window)
glut_window->swap_buffers();
}
void Fl_Glut_Window::draw_overlay() {
@ -389,12 +391,12 @@ void glutRemoveMenuItem(int item) {
int glutGet(GLenum type) {
switch (type) {
case GLUT_RETURN_ZERO: return 0;
case GLUT_WINDOW_X: return glut_window->x();
case GLUT_WINDOW_Y: return glut_window->y();
case GLUT_WINDOW_WIDTH: return glut_window->pixel_w();
case GLUT_WINDOW_HEIGHT: return glut_window->pixel_h();
case GLUT_WINDOW_X: return glut_window ? glut_window->x() : 0;
case GLUT_WINDOW_Y: return glut_window ? glut_window->y() : 0;
case GLUT_WINDOW_WIDTH: return glut_window ? glut_window->pixel_w() : 0;
case GLUT_WINDOW_HEIGHT: return glut_window ? glut_window->pixel_h() : 0;
case GLUT_WINDOW_PARENT:
if (glut_window->parent())
if (glut_window && glut_window->parent())
return ((Fl_Glut_Window *)(glut_window->parent()))->number;
else
return 0;
@ -432,11 +434,11 @@ int glutGet(GLenum type) {
int glutLayerGet(GLenum type) {
switch (type) {
case GLUT_OVERLAY_POSSIBLE: return glut_window->can_do_overlay();
case GLUT_OVERLAY_POSSIBLE: return glut_window ? glut_window->can_do_overlay() : 0;
//case GLUT_LAYER_IN_USE:
//case GLUT_HAS_OVERLAY:
case GLUT_TRANSPARENT_INDEX: return 0; // true for SGI
case GLUT_NORMAL_DAMAGED: return glut_window->damage();
case GLUT_NORMAL_DAMAGED: return glut_window ? glut_window->damage() : 0;
case GLUT_OVERLAY_DAMAGED: return 1; // kind of works...
default: return 0;
}

6
test/CMakeLists.txt
View File

@ -87,11 +87,17 @@ CREATE_EXAMPLE (flex_login flex_login.cxx fltk)
CREATE_EXAMPLE (fltk-versions fltk-versions.cxx fltk)
CREATE_EXAMPLE (fonts fonts.cxx fltk)
CREATE_EXAMPLE (forms forms.cxx "fltk_forms;fltk")
if (OPENGL_FOUND)
CREATE_EXAMPLE (glut_test glut_test.cxx "fltk_gl;fltk")
endif()
if (OPENGL_FOUND)
CREATE_EXAMPLE (handle_events handle_events.cxx "fltk_gl;fltk") # opt. Fl_Gl_Window
else()
CREATE_EXAMPLE (handle_events handle_events.cxx fltk) # w/o Fl_Gl_Window
endif()
CREATE_EXAMPLE (hello hello.cxx fltk)
CREATE_EXAMPLE (help_dialog help_dialog.cxx "fltk_images;fltk")
CREATE_EXAMPLE (icon icon.cxx fltk)

7
test/Makefile
View File

@ -75,6 +75,7 @@ CPPFILES =\
fullscreen.cxx \
gl_overlay.cxx \
glpuzzle.cxx \
glut_test.cxx \
hello.cxx \
help_dialog.cxx \
icon.cxx \
@ -226,6 +227,7 @@ GLALL = \
fullscreen$(EXEEXT) \
gl_overlay$(EXEEXT) \
glpuzzle$(EXEEXT) \
glut_test$(EXEEXT) \
shape$(EXEEXT) \
unittests$(EXEEXT)
@ -661,6 +663,11 @@ gl_overlay$(EXEEXT): gl_overlay.o
$(CXX) $(ARCHFLAGS) $(CXXFLAGS) $(LDFLAGS) -o $@ gl_overlay.o $(LINKFLTKGL) $(LINKFLTK) $(GLDLIBS)
$(OSX_ONLY) ../fltk-config --post $@
glut_test$(EXEEXT): glut_test.o
echo Linking $@...
$(CXX) $(ARCHFLAGS) $(CXXFLAGS) $(LDFLAGS) -o $@ glut_test.o $(LINKFLTKGL) $(LINKFLTK) $(GLDLIBS)
$(OSX_ONLY) ../fltk-config --post $@
unittests$(EXEEXT): $(OBJUNITTEST)
echo Linking $@...
$(CXX) $(ARCHFLAGS) $(CXXFLAGS) $(LDFLAGS) -o $@ $(OBJUNITTEST) $(LINKFLTKGL) $(LINKFLTK) $(GLDLIBS)

172
test/glut_test.cxx Normal file
View File

@ -0,0 +1,172 @@
//
// GLUT test program for the Fast Light Tool Kit (FLTK).
//
// Provided by Brian Schack (STR #3458, see "big.cxx").
// Copyright 2023 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:
//
// https://www.fltk.org/COPYING.php
//
// Please see the following page on how to report bugs and issues:
//
// https://www.fltk.org/bugs.php
//
// Thanks to the original author Brian Schack for this test program.
// This program has been extended to test several GLUT functions with
// (1) a valid and (2) an invalid (destroyed) GLUT window.
// The test program opens two GLUT windows, runs the tests, prints
// diagnostics on stdout, and exits immediately. This is intended.
// To compile (examples with different GLUT implementations)
// as of Apr 03, 2018 provided Brian Schack, slightly modified
//
// macOS GLUT:
// g++ -o glut_test glut_test.cxx -framework OpenGL -framework GLUT
//
// FreeGLUT (on macOS, with Macport's FreeGLUT):
// g++ -o glut_test glut_test.cxx -framework OpenGL -I/opt/local/include -L/opt/local/lib -lglut
//
// FLTK
// fltk-config --use-gl --compile glut_test.cxx
// Enable one of the following two #include's depending on the GLUT implementation
// #include <GLUT/glut.h> // GLUT and FreeGLUT version
#include <FL/glut.H> // FLTK version
#include <stdio.h>
// Empty callback functions for testing.
void displayFunc() {}
void reshapeFunc(int w, int h) {}
void keyboardFunc(unsigned char key, int x, int y) {}
void mouseFunc(int b, int state, int x, int y) {}
void motionFunc(int x, int y) {}
void passiveMotionFunc(int x, int y) {}
void entryFunc(int s) {}
void visibilityFunc(int s) {}
void idleFunc() {}
void timerFunc(int value) {}
void menuStateFunc(int state) {}
void menuStatusFunc(int status, int x, int y) {}
void specialFunc(int key, int x, int y) {}
void overlayDisplayFunc() {}
int main(int argc, char **argv) {
glutInit(&argc, argv);
// Create 2 windows.
int win1 = glutCreateWindow("Window 1");
int win2 = glutCreateWindow("Window 2");
printf("Window 1 created, number = %d\n", win1);
printf("Window 2 created, number = %d\n", win2);
// Run tests twice, with (1) a valid and (2) an invalid current window
for (int i = 0; i < 2; i++) {
// Find out which window is current.
int current = glutGetWindow();
printf("Window %d is current\n", current);
// Ask GLUT to redisplay things.
glutPostRedisplay();
// Set window title
glutSetWindowTitle((char *)"Non-existent");
// Set icon title
glutSetIconTitle((char *)"Non-existent");
// Position window
glutPositionWindow(10, 20);
// Reshape window
glutReshapeWindow(100, 200);
// Pop window
glutPopWindow();
// Iconify window
glutIconifyWindow();
// Show window
glutShowWindow();
// Hide window
glutHideWindow();
// Go to full screen mode
glutFullScreen();
// Set the cursor
glutSetCursor(GLUT_CURSOR_INFO);
// Establish an overlay
glutEstablishOverlay();
// Remove overlay
glutRemoveOverlay();
// Choose a layer
glutUseLayer(GLUT_NORMAL);
glutUseLayer(GLUT_OVERLAY);
// Post display on a layer
glutPostOverlayRedisplay();
// Show overlay
glutShowOverlay();
// Hide overlay
glutHideOverlay();
// Attach a menu
glutAttachMenu(0);
// Detach a menu
glutDetachMenu(0);
// Specify callbacks
glutDisplayFunc(displayFunc);
glutReshapeFunc(reshapeFunc);
glutKeyboardFunc(keyboardFunc);
glutMouseFunc(mouseFunc);
glutMotionFunc(motionFunc);
glutPassiveMotionFunc(passiveMotionFunc);
glutEntryFunc(entryFunc);
glutVisibilityFunc(visibilityFunc);
glutIdleFunc(idleFunc);
glutTimerFunc(1000, timerFunc, 42);
glutMenuStateFunc(menuStateFunc);
glutMenuStatusFunc(menuStatusFunc);
glutSpecialFunc(specialFunc);
glutOverlayDisplayFunc(overlayDisplayFunc);
// Swap buffers
glutSwapBuffers();
// GLUT gets
printf("GLUT_WINDOW_X = %d\n", glutGet(GLUT_WINDOW_X));
printf("GLUT_WINDOW_Y = %d\n", glutGet(GLUT_WINDOW_Y));
printf("GLUT_WINDOW_WIDTH = %d\n", glutGet(GLUT_WINDOW_WIDTH));
printf("GLUT_WINDOW_HEIGHT = %d\n", glutGet(GLUT_WINDOW_HEIGHT));
printf("GLUT_WINDOW_PARENT = %d\n", glutGet(GLUT_WINDOW_PARENT));
// GLUT layer gets
printf("GLUT_OVERLAY_POSSIBLE = %d\n", glutLayerGet(GLUT_OVERLAY_POSSIBLE));
printf("GLUT_NORMAL_DAMAGED = %d\n", glutLayerGet(GLUT_NORMAL_DAMAGED));
// Destroy the current window - this sets glut_window to NULL
printf("Destroy the current window (%d)\n\n", glutGetWindow());
glutDestroyWindow(current);
} // loop with current window
printf("All tests done, exiting.\n");
return 0;
}