From c1ab4a2ab36584354ad7476758a96977a5383bba Mon Sep 17 00:00:00 2001
From: gutmet <me.git@gutmet.org>
Date: Sat, 13 Mar 2021 17:43:27 +0100
Subject: [PATCH] add centeredmaster layout, bind to Mod+c

---
 config.def.h |  2 ++
 dwm.c        | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/config.def.h b/config.def.h
index 1992ca8..ea26ac2 100644
--- a/config.def.h
+++ b/config.def.h
@@ -46,6 +46,7 @@ static const Layout layouts[] = {
 	{ "[]=",      tile },    /* first entry is default */
 	{ "><>",      NULL },    /* no layout function means floating behavior */
 	{ "[M]",      monocle },
+	{ "|M|",      centeredmaster },
 };
 
 /* key definitions */
@@ -83,6 +84,7 @@ static Key keys[] = {
 	{ MODKEY,                       XK_t,      setlayout,      {.v = &layouts[0]} },
 	{ MODKEY,                       XK_f,      setlayout,      {.v = &layouts[1]} },
 	{ MODKEY,                       XK_m,      setlayout,      {.v = &layouts[2]} },
+	{ MODKEY,                       XK_c,      setlayout,      {.v = &layouts[3]} },
 	{ MODKEY,                       XK_space,  setlayout,      {0} },
 	{ MODKEY|ShiftMask,             XK_space,  togglefloating, {0} },
 	{ MODKEY,                       XK_0,      view,           {.ui = ~0 } },
diff --git a/dwm.c b/dwm.c
index d8ba21c..e0c960b 100644
--- a/dwm.c
+++ b/dwm.c
@@ -173,6 +173,7 @@ static void arrangemon(Monitor *m);
 static void attach(Client *c);
 static void attachstack(Client *c);
 static void buttonpress(XEvent *e);
+static void centeredmaster(Monitor *m);
 static void checkotherwm(void);
 static void cleanup(void);
 static void cleanupautostart(void);
@@ -495,6 +496,59 @@ buttonpress(XEvent *e)
 			buttons[i].func(click == ClkTagBar && buttons[i].arg.i == 0 ? &arg : &buttons[i].arg);
 }
 
+void
+centeredmaster(Monitor *m)
+{
+	unsigned int i, n, h, mw, mx, my, oty, ety, tw;
+	Client *c;
+
+	/* count number of clients in the selected monitor */
+	for (n = 0, c = nexttiled(m->clients); c; c = nexttiled(c->next), n++);
+	if (n == 0)
+		return;
+
+	/* initialize areas */
+	mw = m->ww;
+	mx = 0;
+	my = 0;
+	tw = mw;
+
+	if (n > m->nmaster) {
+		/* go mfact box in the center if more than nmaster clients */
+		mw = m->nmaster ? m->ww * m->mfact : 0;
+		tw = m->ww - mw;
+
+		if (n - m->nmaster > 1) {
+			/* only one client */
+			mx = (m->ww - mw) / 2;
+			tw = (m->ww - mw) / 2;
+		}
+	}
+
+	oty = 0;
+	ety = 0;
+	for (i = 0, c = nexttiled(m->clients); c; c = nexttiled(c->next), i++)
+	{
+		if (i < m->nmaster) {
+			/* nmaster clients are stacked vertically, in the center of the screen */
+			h = (m->wh - my) / (MIN(n, m->nmaster) - i);
+			resize(c, m->wx + mx, m->wy + my, mw - (2*c->bw), h - (2*c->bw), 0);
+			my += HEIGHT(c);
+		} else {
+			/* stack clients are stacked vertically */
+			if ((i - m->nmaster) % 2 ) {
+				h = (m->wh - ety) / ( (1 + n - i) / 2);
+				resize(c, m->wx, m->wy + ety, tw - (2*c->bw), h - (2*c->bw), 0);
+				ety += HEIGHT(c);
+			} else {
+				h = (m->wh - oty) / ((1 + n - i) / 2);
+				resize(c, m->wx + mx + mw, m->wy + oty, tw - (2*c->bw), h - (2*c->bw), 0);
+				oty += HEIGHT(c);
+			}
+		}
+	}
+}
+
 void
 checkotherwm(void)
 {