I'm developing a openGL application for X windows and am currently looking at
different ways to "fullscreen" a window. Resizing is not so much the
challenge as removing the window decoration.
FVWM is actually not a problem, since it responds to "motif hints" which are
used in common libraries with openGL. However, it also responds to EWMH hints,
and I am wondering if anyone here has any experience using these.
I've attached the code I am currently using, the relevant function is
fullscreenEWMH (about 45 lines). Again, this works on fvwm, but returns an X
"Bad Request" error anyway. This may be an Xlib, and not a fvwm issue. On
metacity, it functions erratically, which is why I am trying to determine the
most proper method. The metacity-devel mailing list unfortunately seems to be
abandoned. I'm also inquiring with the XDG people.
Sorry if this seems slightly off topic, I'm just hoping somebody here might
have a simple quick answer about FULLSCREEN using "extended window manager
hints".
--
MK <[email protected]>
/* window.c
Some window managers (eg. metacity) really don't like glutFullScreen (Motif
hints) and may even crash the app.
Hopefully they are EWMH compliant! */
int checkEWMH(void) {
Display *disp = XOpenDisplay(NULL);
int form, retv = 0;
unsigned long len, len2, i, j, remain;
Window *list = NULL;
char *name;
Atom *actions;
Atom act, prop, type;
if (!disp) return 0;
if (!(list = winlist(disp,&len))) return 0;
prop = XInternAtom(disp,"_NET_WM_ALLOWED_ACTIONS",False);
act = XInternAtom(disp,"_NET_WM_ACTION_FULLSCREEN",False);
for (i=0;i<len;i++) {
name = winame(disp,list[i]);
if (!strcmp(name,GAMENAME)) {
XFree(name);
if
(XGetWindowProperty(disp,list[i],prop,0,1024,False,XA_ATOM,
&type,&form,&len2,&remain,(unsigned
char**)&actions) != Success) {
XFree(list);
return 0;
}
for (j=0;j<len2;j++)
if (act == actions[j]) retv = 1;
XFree(actions);
break;
}
XFree(name);
}
XFree(list);
return retv;
}
void fullscreenEWMH(void) { /* prototype matches glutFullScreen() */
Window *list = NULL;
Display *disp = XOpenDisplay(NULL);
XEvent event;
unsigned long len, i;
//long mask = SubstructureNotifyMask;
//long mask = StructureNotifyMask | ResizeRedirectMask;
long mask = SubstructureRedirectMask | SubstructureNotifyMask;
//long mask = PropertyChangeMask;
char *name;
Status r;
if (!disp) return;
if (!(list = winlist(disp,&len))) return;
for (i=0;i<len;i++) {
name = winame(disp,list[i]);
if (!strcmp(name,GAMENAME)) {
XFree(name);
break;
}
XFree(name);
}
if (i == len) {
XFree(list);
return;
}
event.xclient.type = ClientMessage;
event.xclient.serial = 0;
event.xclient.send_event = True;
event.xclient.display = disp;
event.xclient.window = list[i];
event.xclient.message_type = XInternAtom(disp,"_NET_WM_STATE",False);
event.xclient.format = 32;
event.xclient.data.l[0] = 1; /* set (2 is toggle) */
event.xclient.data.l[1] =
XInternAtom(disp,"_NET_WM_STATE_FULLSCREEN",False);
event.xclient.data.l[2] = 0;
event.xclient.data.l[3] = 0;
event.xclient.data.l[4] = 0;
if ((r = XSendEvent(disp,XDefaultRootWindow(disp),False,mask,&event))
!= Success)
fprintf(stderr, "Couldn't get fullscreen...X error: %d\n", r);
XFree(list);
}
Window *winlist (Display *disp, unsigned long *len) {
Atom prop = XInternAtom(disp,"_NET_CLIENT_LIST",False), type;
int form;
unsigned long remain;
unsigned char *list;
if
(XGetWindowProperty(disp,XDefaultRootWindow(disp),prop,0,1024,False,XA_WINDOW,&type,&form,len,&remain,&list)
!= Success)
return NULL;
return (Window*)list;
}
char *winame (Display *disp, Window win) {
Atom prop = XInternAtom(disp,"WM_NAME",False), type;
int form;
unsigned long remain, len;
unsigned char *list;
if
(XGetWindowProperty(disp,win,prop,0,1024,False,XA_STRING,&type,&form,&len,&remain,&list)
!= Success) return NULL;
return (char*)list;
}
