I introduced {H,V}RATIO and inc{h,v,}ratio() functions - the default behaves like in dwm-4.3, config.arg.h shows how I prefer the ratio being handled (for the future I plan to change const char *arg into ..., and renaming Client into Win.)

config.arg.h

@@ -31,7 +31,8 @@ static Layout layout[] = { \
 	{ "><>",		floating }, \
 };
 #define NMASTER			1	/* clients in master area */
-#define RATIO			.8	/* ratio of tile */
+#define HRATIO			.8	/* horizontal ratio of tile */
+#define VRATIO			.8	/* vertical ratio of tile */
 #define SNAP			32	/* snap pixel */
 
 /* key definitions */
@@ -46,8 +47,10 @@ static Key key[] = { \
 		"exec urxvtcd -tr -bg '#222' -fg '#eee' -cr '#eee' +sb -fn '"FONT"'" }, \
 	{ MODKEY,			XK_space,	setlayout,	NULL }, \
 	{ MODKEY,			XK_b,		togglebar,	NULL }, \
-	{ MODKEY,			XK_h,		incratio,	".1" }, \
-	{ MODKEY,			XK_l,		incratio,	"-.1" }, \
+	{ MODKEY,			XK_h,		incvratio,	".1" }, \
+	{ MODKEY,			XK_h,		inchratio,	".1" }, \
+	{ MODKEY,			XK_l,		incvratio,	"-.1" }, \
+	{ MODKEY,			XK_l,		inchratio,	"-.1" }, \
 	{ MODKEY|ShiftMask,		XK_j,		incnmaster,	"1" }, \
 	{ MODKEY|ShiftMask,		XK_k,		incnmaster,	"-1" }, \
 	{ MODKEY,			XK_j,		focusclient,	"1" }, \

config.default.h

@@ -32,7 +32,8 @@ static Layout layout[] = { \
 	{ "><>",		floating }, \
 };
 #define NMASTER			1	/* clients in master area */
-#define RATIO			.8	/* ratio of tile */
+#define HRATIO			.8	/* horizontal ratio of tile */
+#define VRATIO			1	/* vertical ratio of tile */
 #define SNAP			32	/* snap pixel */
 
 /* key definitions */
@@ -44,8 +45,8 @@ static Key key[] = { \
 	{ MODKEY,			XK_p,		spawn, 		"exe=`dmenu_path | dmenu` && exec $exe" }, \
 	{ MODKEY,			XK_space,	setlayout,	NULL }, \
 	{ MODKEY,			XK_b,		togglebar,	NULL }, \
-	{ MODKEY,			XK_h,		incratio,	".1" }, \
-	{ MODKEY,			XK_l,		incratio,	"-.1" }, \
+	{ MODKEY,			XK_h,		incvratio,	".1" }, \
+	{ MODKEY,			XK_l,		incvratio,	"-.1" }, \
 	{ MODKEY|ShiftMask,		XK_j,		incnmaster,	"1" }, \
 	{ MODKEY|ShiftMask,		XK_k,		incnmaster,	"-1" }, \
 	{ MODKEY,			XK_j,		focusclient,	"1" }, \

dwm.h

@@ -44,7 +44,6 @@ enum { WMProtocols, WMDelete, WMState, WMLast };	/* default atoms */
 typedef struct Client Client;
 struct Client {
 	char name[256];
-	float scale;
 	int x, y, w, h;
 	int rx, ry, rw, rh; /* revert geometry */
 	int basew, baseh, incw, inch, maxw, maxh, minw, minh;
@@ -123,7 +122,8 @@ void grabkeys(void);			/* grab all keys defined in config.h */
 /* layout.c */
 void floating(void);			/* arranges all windows floating */
 void focusclient(const char *arg);	/* focuses next(1)/previous(-1) visible client */
-void incratio(const char *arg);		/* increments the tile ratio with arg's value */
+void inchratio(const char *arg);	/* increments the horizontal tile ratio with arg's value */
+void incvratio(const char *arg);	/* increments the vertical tile ratio with arg's value */
 void incnmaster(const char *arg);	/* increments nmaster with arg's index value */
 void initlayouts(void);			/* initialize layout array */
 Client *nexttiled(Client *c);		/* returns tiled successor of c */

layout.c

@@ -8,10 +8,29 @@ Layout *lt = NULL;
 
 /* static */
 
-static double ratio = RATIO;
+static double hratio = HRATIO;
+static double vratio = VRATIO;
 static unsigned int nlayouts = 0;
 static unsigned int nmaster = NMASTER;
 
+static void
+incratio(const char *arg, double *ratio, double def) {
+	double delta;
+
+	if(lt->arrange != tile)
+		return;
+	if(!arg)
+		*ratio = def;
+	else {
+		if(1 == sscanf(arg, "%lf", &delta)) {
+			if(delta + (*ratio) < .1 || delta + (*ratio) > 1.9)
+				return;
+			*ratio += delta;
+		}
+	}
+	lt->arrange();
+}
+
 static double /* simple pow() */
 spow(double x, double y)
 {
@@ -31,21 +50,21 @@ tile(void) {
 	for(n = 0, c = nexttiled(clients); c; c = nexttiled(c->next))
 		n++;
 
-	mw = (n <= nmaster) ? waw :  waw / (1 + ratio);
+	mw = (n <= nmaster) ? waw :  waw / (1 + hratio);
 	tw = waw - mw;
 
 	if(n > 0) {
 		if(n < nmaster) {
 			for(i = 0; i < n; i++)
-				sum += spow(ratio, i);
+				sum += spow(vratio, i);
 			mscale = wah / sum;
 		}
 		else {
 			for(i = 0; i < nmaster; i++)
-				sum += spow(ratio, i);
+				sum += spow(vratio, i);
 			mscale = wah / sum;
 			for(sum = 0, i = 0; i < (n - nmaster); i++)
-				sum += spow(ratio, i);
+				sum += spow(vratio, i);
 			tscale = wah / sum;
 		}
 	}
@@ -62,7 +81,7 @@ tile(void) {
 				if(i + 1 == n || i + 1 == nmaster)
 					nh = (way + wah) - ny - (2 * c->border);
 				else
-					nh = (mscale * spow(ratio, i)) - (2 * c->border);
+					nh = (mscale * spow(vratio, i)) - (2 * c->border);
 			}
 			else { /* tile window */
 				if(i == nmaster) {
@@ -73,7 +92,7 @@ tile(void) {
 				if(i + 1 == n)
 					nh = (way + wah) - ny - (2 * c->border);
 				else
-					nh = (tscale * spow(ratio, i - nmaster)) - (2 * c->border);
+					nh = (tscale * spow(vratio, i - nmaster)) - (2 * c->border);
 			}
 			if(nh < bh) {
 				nh = bh;
@@ -133,21 +152,13 @@ focusclient(const char *arg) {
 }
 
 void
-incratio(const char *arg) {
-	double delta;
-
-	if(lt->arrange != tile)
-		return;
-	if(!arg)
-		ratio = RATIO;
-	else {
-		if(1 == sscanf(arg, "%lf", &delta)) {
-			if(delta + ratio < .1 || delta + ratio > 1.9)
-				return;
-			ratio += delta;
-		}
+inchratio(const char *arg) {
+	incratio(arg, &hratio, HRATIO);
 }
-	lt->arrange();
+
+void
+incvratio(const char *arg) {
+	incratio(arg, &vratio, VRATIO);
 }
 
 void