nix-config/assets/dwm-savefloats-alwayscenter.patch

diff --git a/dwm.c b/dwm.c
index 67c6b2b..ed46374 100644
--- a/dwm.c
+++ b/dwm.c
@@ -88,6 +88,7 @@ struct Client {
 	char name[256];
 	float mina, maxa;
 	int x, y, w, h;
+	int sfx, sfy, sfw, sfh; /* stored float geometry, used on mode revert */
 	int oldx, oldy, oldw, oldh;
 	int basew, baseh, incw, inch, maxw, maxh, minw, minh, hintsvalid;
 	int bw, oldbw;
@@ -1068,6 +1069,12 @@ manage(Window w, XWindowAttributes *wa)
 	updatewindowtype(c);
 	updatesizehints(c);
 	updatewmhints(c);
+	c->x = c->mon->mx + (c->mon->mw - WIDTH(c)) / 2;
+	c->y = c->mon->my + (c->mon->mh - HEIGHT(c)) / 2;
+	c->sfx = c->x;
+	c->sfy = c->y;
+	c->sfw = c->w;
+	c->sfh = c->h;
 	XSelectInput(dpy, w, EnterWindowMask|FocusChangeMask|PropertyChangeMask|StructureNotifyMask);
 	grabbuttons(c, 0);
 	if (!c->isfloating)
@@ -1730,8 +1737,16 @@ togglefloating(const Arg *arg)
 		return;
 	selmon->sel->isfloating = !selmon->sel->isfloating || selmon->sel->isfixed;
 	if (selmon->sel->isfloating)
-		resize(selmon->sel, selmon->sel->x, selmon->sel->y,
-			selmon->sel->w, selmon->sel->h, 0);
+		/* restore last known float dimensions */
+		resize(selmon->sel, selmon->sel->sfx, selmon->sel->sfy,
+		       selmon->sel->sfw, selmon->sel->sfh, False);
+	else {
+		/* save last known float dimensions */
+		selmon->sel->sfx = selmon->sel->x;
+		selmon->sel->sfy = selmon->sel->y;
+		selmon->sel->sfw = selmon->sel->w;
+		selmon->sel->sfh = selmon->sel->h;
+	}
 	arrange(selmon);
 }