From 919bde7cb1e8961cfb474013bded00f81ae58435 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Thu, 14 Mar 2013 12:08:26 +0000
Subject: [PATCH] When only two panes in a window, only draw half the
 separating line as active.

---
 screen-redraw.c | 57 +++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 53 insertions(+), 4 deletions(-)

diff --git a/screen-redraw.c b/screen-redraw.c
index 14b73164..a7bf81ff 100644
--- a/screen-redraw.c
+++ b/screen-redraw.c
@@ -24,7 +24,11 @@
 
 int	screen_redraw_cell_border1(struct window_pane *, u_int, u_int);
 int	screen_redraw_cell_border(struct client *, u_int, u_int);
-int	screen_redraw_check_cell(struct client *, u_int, u_int);
+int	screen_redraw_check_cell(struct client *, u_int, u_int,
+	    struct window_pane **);
+int	screen_redraw_check_active(u_int, u_int, int, struct window *,
+	    struct window_pane *);
+
 void	screen_redraw_draw_number(struct client *, struct window_pane *);
 
 #define CELL_INSIDE 0
@@ -93,7 +97,8 @@ screen_redraw_cell_border(struct client *c, u_int px, u_int py)
 
 /* Check if cell inside a pane. */
 int
-screen_redraw_check_cell(struct client *c, u_int px, u_int py)
+screen_redraw_check_cell(struct client *c, u_int px, u_int py,
+    struct window_pane **wpp)
 {
 	struct window		*w = c->session->curw->window;
 	struct window_pane	*wp;
@@ -105,6 +110,7 @@ screen_redraw_check_cell(struct client *c, u_int px, u_int py)
 	TAILQ_FOREACH(wp, &w->panes, entry) {
 		if (!window_pane_visible(wp))
 			continue;
+		*wpp = wp;
 
 		/* If outside the pane and its border, skip it. */
 		if ((wp->xoff != 0 && px < wp->xoff - 1) ||
@@ -162,9 +168,52 @@ screen_redraw_check_cell(struct client *c, u_int px, u_int py)
 		}
 	}
 
+	*wpp = NULL;
 	return (CELL_OUTSIDE);
 }
 
+/* Check active pane indicator. */
+int
+screen_redraw_check_active(u_int px, u_int py, int type, struct window *w,
+    struct window_pane *wp)
+{
+	/* Is this off the active pane border? */
+	if (screen_redraw_cell_border1(w->active, px, py) != 1)
+		return (0);
+
+	/* If there are more than two panes, that's enough. */
+	if (window_count_panes(w) != 2)
+		return (1);
+
+	/* Else if the cell is not a border cell, forget it. */
+	if (wp == NULL || (type == CELL_OUTSIDE || type == CELL_INSIDE))
+		return (1);
+
+	/* Check if the pane covers the whole width. */
+	if (wp->xoff == 0 && wp->sx == w->sx) {
+		/* This can either be the top pane or the bottom pane. */
+		if (wp->yoff == 0) { /* top pane */
+			if (wp == w->active)
+				return (px <= wp->sx / 2);
+			return (px > wp->sx / 2);
+		}
+		return (0);
+	}
+
+	/* Check if the pane covers the whole height. */
+	if (wp->yoff == 0 && wp->sy == w->sy) {
+		/* This can either be the left pane or the right pane. */
+		if (wp->xoff == 0) { /* left pane */
+			if (wp == w->active)
+				return (py <= wp->sy / 2);
+			return (py > wp->sy / 2);
+		}
+		return (0);
+	}
+
+	return (type);
+}
+
 /* Redraw entire screen. */
 void
 screen_redraw_screen(struct client *c, int status_only, int borders_only)
@@ -223,10 +272,10 @@ screen_redraw_screen(struct client *c, int status_only, int borders_only)
 				break;
 		}
 		for (i = 0; i < tty->sx; i++) {
-			type = screen_redraw_check_cell(c, i, j);
+			type = screen_redraw_check_cell(c, i, j, &wp);
 			if (type == CELL_INSIDE)
 				continue;
-			if (screen_redraw_cell_border1(w->active, i, j) == 1)
+			if (screen_redraw_check_active(i, j, type, w, wp))
 				tty_attributes(tty, &active_gc);
 			else
 				tty_attributes(tty, &other_gc);