From af16ce6ad9170e6a48e79e3af696f60daa2bae1d Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Mon, 14 Sep 2015 11:34:50 +0000
Subject: [PATCH] When the active pane changes, redraw panes if the style has
 changed. From Cam Hutchison.

---
 cmd-select-pane.c | 28 +++++++++++++++++-----------
 style.c           | 12 ++++++++++++
 tmux.h            |  4 ++++
 window.c          | 24 ++++++++++++++++++++++++
 4 files changed, 57 insertions(+), 11 deletions(-)

diff --git a/cmd-select-pane.c b/cmd-select-pane.c
index 5ea4bdc3..e76587cc 100644
--- a/cmd-select-pane.c
+++ b/cmd-select-pane.c
@@ -47,6 +47,7 @@ cmd_select_pane_exec(struct cmd *self, struct cmd_q *cmdq)
 {
 	struct args		*args = self->args;
 	struct winlink		*wl;
+	struct window		*w;
 	struct session		*s;
 	struct window_pane	*wp, *lastwp, *markedwp;
 	const char		*style;
@@ -55,21 +56,24 @@ cmd_select_pane_exec(struct cmd *self, struct cmd_q *cmdq)
 		wl = cmd_find_window(cmdq, args_get(args, 't'), NULL);
 		if (wl == NULL)
 			return (CMD_RETURN_ERROR);
+		w = wl->window;
 
-		if (wl->window->last == NULL) {
+		if (w->last == NULL) {
 			cmdq_error(cmdq, "no last pane");
 			return (CMD_RETURN_ERROR);
 		}
 
 		if (args_has(self->args, 'e'))
-			wl->window->last->flags &= ~PANE_INPUTOFF;
+			w->last->flags &= ~PANE_INPUTOFF;
 		else if (args_has(self->args, 'd'))
-			wl->window->last->flags |= PANE_INPUTOFF;
+			w->last->flags |= PANE_INPUTOFF;
 		else {
-			server_unzoom_window(wl->window);
-			window_set_active_pane(wl->window, wl->window->last);
-			server_status_window(wl->window);
-			server_redraw_window_borders(wl->window);
+			server_unzoom_window(w);
+			window_redraw_active_switch(w, w->last);
+			if (window_set_active_pane(w, w->last)) {
+				server_status_window(w);
+				server_redraw_window_borders(w);
+			}
 		}
 
 		return (CMD_RETURN_NORMAL);
@@ -77,6 +81,7 @@ cmd_select_pane_exec(struct cmd *self, struct cmd_q *cmdq)
 
 	if ((wl = cmd_find_pane(cmdq, args_get(args, 't'), &s, &wp)) == NULL)
 		return (CMD_RETURN_ERROR);
+	w = wl->window;
 
 	if (args_has(args, 'm') || args_has(args, 'M')) {
 		if (args_has(args, 'm') && !window_pane_visible(wp))
@@ -135,16 +140,17 @@ cmd_select_pane_exec(struct cmd *self, struct cmd_q *cmdq)
 		return (CMD_RETURN_NORMAL);
 	}
 
-	if (wp == wl->window->active)
+	if (wp == w->active)
 		return (CMD_RETURN_NORMAL);
 	server_unzoom_window(wp->window);
 	if (!window_pane_visible(wp)) {
 		cmdq_error(cmdq, "pane not visible");
 		return (CMD_RETURN_ERROR);
 	}
-	if (window_set_active_pane(wl->window, wp)) {
-		server_status_window(wl->window);
-		server_redraw_window_borders(wl->window);
+	window_redraw_active_switch(w, wp);
+	if (window_set_active_pane(w, wp)) {
+		server_status_window(w);
+		server_redraw_window_borders(w);
 	}
 
 	return (CMD_RETURN_NORMAL);
diff --git a/style.c b/style.c
index 9fafdd1d..c00b0fee 100644
--- a/style.c
+++ b/style.c
@@ -252,3 +252,15 @@ style_apply_update(struct grid_cell *gc, struct options *oo, const char *name)
 	if (gcp->attr != 0)
 		gc->attr |= gcp->attr;
 }
+
+/* Check if two styles are the same. */
+int
+style_equal(const struct grid_cell *gc1, const struct grid_cell *gc2)
+{
+	return gc1->fg == gc2->fg &&
+		gc1->bg == gc2->bg &&
+		(gc1->flags & ~GRID_FLAG_PADDING) ==
+		(gc2->flags & ~GRID_FLAG_PADDING) &&
+		(gc1->attr & ~GRID_ATTR_CHARSET) ==
+		(gc2->attr & ~GRID_ATTR_CHARSET);
+}
diff --git a/tmux.h b/tmux.h
index e5523418..5b1f0f33 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1983,6 +1983,8 @@ struct window_pane *window_get_active_at(struct window *, u_int, u_int);
 struct window_pane *window_find_string(struct window *, const char *);
 int		 window_has_pane(struct window *, struct window_pane *);
 int		 window_set_active_pane(struct window *, struct window_pane *);
+void		 window_redraw_active_switch(struct window *,
+		     struct window_pane *);
 struct window_pane *window_add_pane(struct window *, u_int);
 void		 window_resize(struct window *, u_int, u_int);
 int		 window_zoom(struct window_pane *);
@@ -2210,5 +2212,7 @@ void		 style_apply(struct grid_cell *, struct options *,
 		     const char *);
 void		 style_apply_update(struct grid_cell *, struct options *,
 		     const char *);
+int		 style_equal(const struct grid_cell *,
+		     const struct grid_cell *);
 
 #endif /* TMUX_H */
diff --git a/window.c b/window.c
index e5decdc4..9e77adcd 100644
--- a/window.c
+++ b/window.c
@@ -423,6 +423,30 @@ window_set_active_pane(struct window *w, struct window_pane *wp)
 	return (1);
 }
 
+void
+window_redraw_active_switch(struct window *w, struct window_pane *wp)
+{
+	const struct grid_cell	*agc, *wgc;
+
+	if (wp == w->active)
+		return;
+
+	/*
+	 * If window-style and window-active-style are the same, we don't need
+	 * to redraw panes when switching active panes. Otherwise, if the
+	 * active or inactive pane do not have a custom style, they will need
+	 * to be redrawn.
+	 */
+	agc = options_get_style(&w->options, "window-active-style");
+	wgc = options_get_style(&w->options, "window-style");
+	if (style_equal(agc, wgc))
+		return;
+	if (style_equal(&grid_default_cell, &w->active->colgc))
+		w->active->flags |= PANE_REDRAW;
+	if (style_equal(&grid_default_cell, &wp->colgc))
+		wp->flags |= PANE_REDRAW;
+}
+
 struct window_pane *
 window_get_active_at(struct window *w, u_int x, u_int y)
 {