- allow per-screen gap; not (yet) user configurable.

- teach _NET_WORKAREA about gap.

ok oga@

calmwm.h

@@ -65,6 +65,12 @@ struct color {
 	unsigned long	 pixel;
 	char		*name;
 };
+struct gap {
+	int		 top;
+	int		 bottom;
+	int		 left;
+	int		 right;
+};
 
 struct client_ctx;
 
@@ -97,6 +103,7 @@ struct screen_ctx {
 	int			 xmax;
 	int			 ymax;
 
+	struct gap		 gap;
 	struct cycle_entry_q	 mruq;
 
 	XftDraw			*xftdraw;
@@ -284,6 +291,7 @@ struct conf {
 	int			 bwidth;
 #define	CONF_MAMOUNT		 1
 	int			 mamount;
+	struct gap		 gap;
 
 #define CONF_COLOR_ACTIVEBORDER		"#CCCCCC"
 #define CONF_COLOR_INACTIVEBORDER	"#666666"
@@ -298,7 +306,6 @@ struct conf {
 
 #define	DEFAULTFONTNAME		 "sans-serif:pixelsize=14:bold"
 	char			*DefaultFontName;
-	int			 gap_top, gap_bottom, gap_left, gap_right;
 };
 
 /* Menu stuff */
@@ -423,6 +430,7 @@ void			 conf_bindname(struct conf *, char *, char *);
 void			 conf_mousebind(struct conf *, char *, char *);
 void			 conf_grab_mouse(struct client_ctx *);
 void			 conf_reload(struct conf *);
+void			 conf_gap(struct conf *, struct screen_ctx *);
 void			 conf_font(struct conf *, struct screen_ctx *);
 void			 conf_color(struct conf *, struct screen_ctx *);
 void			 conf_init(struct conf *);