04-centredfloating.diff

diff -up a/dwm.c b/dwm.c
--- a/dwm.c	2012-07-17 17:33:17.308540211 +1000
+++ b/dwm.c	2012-07-17 17:34:23.618180981 +1000
@@ -91,7 +91,7 @@ struct Client {
 	int basew, baseh, incw, inch, maxw, maxh, minw, minh;
 	int bw, oldbw;
 	unsigned int tags;
-	Bool isfixed, isfloating, isurgent, neverfocus, oldstate, isfullscreen;
+	Bool isfixed, isfloating, isurgent, neverfocus, oldstate, isfullscreen, iscentred;
 	Client *next;
 	Client *snext;
 	Monitor *mon;
@@ -151,6 +151,7 @@ typedef struct {
 	const char *title;
 	unsigned int tags;
 	Bool isfloating;
+	Bool iscentred;
 	int monitor;
 } Rule;
 
@@ -302,6 +303,7 @@ applyrules(Client *c) {
 
 	/* rule matching */
 	c->isfloating = c->tags = 0;
+	c->iscentred = 1;
 	XGetClassHint(dpy, c->win, &ch);
 	class    = ch.res_class ? ch.res_class : broken;
 	instance = ch.res_name  ? ch.res_name  : broken;
@@ -313,6 +315,7 @@ applyrules(Client *c) {
 		&& (!r->instance || strstr(instance, r->instance)))
 		{
 			c->isfloating = r->isfloating;
+			c->iscentred = r->iscentred;
 			c->tags |= r->tags;
 			for(m = mons; m && m->num != r->monitor; m = m->next);
 			if(m)
@@ -1162,8 +1165,14 @@ manage(Window w, XWindowAttributes *wa)
 		applyrules(c);
 	}
 	/* geometry */
-	c->x = c->oldx = wa->x;
-	c->y = c->oldy = wa->y;
+	if((!c->mon->lt[c->mon->sellt]->arrange || c->isfloating) && c->iscentred) {
+		c->x = c->oldx = c->mon->wx + (c->mon->ww / 2 - wa->width / 2);
+		c->y = c->oldy = c->mon->wy + (c->mon->wh / 2 - wa->height / 2);
+	}
+	else {
+		c->x = c->oldx = wa->x;
+		c->y = c->oldy = wa->y;
+	}
 	c->w = c->oldw = wa->width;
 	c->h = c->oldh = wa->height;
 	c->oldbw = wa->border_width;