R devel - Mar 2021 - Possible x11 window manager window aggregation under one icon?

On Mon, 22 Mar 2021 15:42:04 -0400
Duncan Murdoch <murdoch.duncan at gmail.com> wrote:
> I'd be happy to add something to rgl if you could point me to 
> an example
On Mon, 22 Mar 2021 14:54:43 -0500
Dirk Eddelbuettel <edd at debian.org> wrote:
> Just like Duncan I see now WM_HINTS yet, so maybe by
> just giving them we can improve?
The surrounding code and
<https://tronche.com/gui/x/xlib/ICC/client-to-window-manager/wm-hints.html>
proved to be enough of an example. The following patch makes it
possible to group x11() windows on my PC with Xfce running:

-----------------------------------8<-----------------------------------
Index: src/modules/X11/devX11.c
==================================================================---
src/modules/X11/devX11.c	(revision 80104)
+++ src/modules/X11/devX11.c	(working copy)
@@ -105,7 +105,7 @@
 static Display *display;			/* Display */
 static char dspname[101]="";
 static int screen;				/* Screen */
-static Window rootwin;				/* Root Window */
+static Window rootwin, group_leader;		/* Root Window, Group leader */
 static Visual *visual;				/* Visual */
 static int depth;				/* Pixmap depth */
 static int Vclass;				/* Visual class */
@@ -1617,6 +1617,16 @@
                             PropModeReplace,
                             (const unsigned char*) rlogo_icon, 2 + 99*77);
 
+	    /* set the window group leader */
+	    XWMHints * hints;
+	    hints = XAllocWMHints();
+	    if (hints) {
+		hints->window_group = group_leader;
+		hints->flags |= WindowGroupHint;
+		XSetWMHints(display, xd->window, hints);
+		XFree(hints);
+	    }
+
 	    /* set up protocols so that window manager sends */
 	    /* me an event when user "destroys" window */
 	    _XA_WM_PROTOCOLS = XInternAtom(display, "WM_PROTOCOLS", 0);
@@ -2109,6 +2119,7 @@
     if (numX11Devices == 0)  {
 	int fd = ConnectionNumber(display);
 	/* Free Resources Here */
+	XDestroyWindow(display, group_leader);
 	while (nfonts--)
 	      R_XFreeFont(display, fontcache[nfonts].font);
 	nfonts = 0;
@@ -3133,6 +3144,9 @@
 #endif
     screen = DefaultScreen(display);
     rootwin = DefaultRootWindow(display);
+    group_leader = XCreateSimpleWindow( /* never mapped or visible */
+	display, rootwin, 0, 0, 1, 1, 0, 0, 0
+    );
     depth = DefaultDepth(display, screen);
     visual = DefaultVisual(display, screen);
     colormap = DefaultColormap(display, screen);
-----------------------------------8<-----------------------------------

Some very limited testing didn't seem to uncover any problems.

-- 
Best regards,
Ivan

-------------- next part --------------
A non-text attachment was scrubbed...
Name: groups.png
Type: image/png
Size: 4393 bytes
Desc: not available
URL:
<https://stat.ethz.ch/pipermail/r-devel/attachments/20210323/b2552350/attachment.png>

On 23 March 2021 at 00:01, Ivan Krylov wrote:
| The surrounding code and
|
<https://tronche.com/gui/x/xlib/ICC/client-to-window-manager/wm-hints.html>
| proved to be enough of an example. The following patch makes it
| possible to group x11() windows on my PC with Xfce running:

[...]

| Some very limited testing didn't seem to uncover any problems.

Woot woot -- works here too under Ubuntu 20.10 / Gnome / Unity.

I applied the adorably small patch to the usual checkout I keep of r-devel
(as an incremental build is faster than a full package build of r-release).

You are my hero. Next round of hot or cold beverages is on me. Already looks
so much better. I may put this into the next 4.0.5 (or 4.1.0 at the latest)
for Debian and Ubuntu (but will instrument a proper new r-base package and
hit it for a few days first).

Do you want to send a proper patch to bugzilla?

Dirk

-- 
https://dirk.eddelbuettel.com | @eddelbuettel | edd at debian.org