Get rid of the PANE_HIDDEN flag in favour of a function, and moving the

decision for whether or not a pane should be drawn out of the layout code and
into the redraw code.

This is needed for the new layout design, getting it in now to make that easier
to work on.

cmd-down-pane.c

@@ -55,7 +55,7 @@ cmd_down_pane_exec(struct cmd *self, struct cmd_ctx *ctx)
 		if (w->active == NULL)
 			w->active = TAILQ_FIRST(&w->panes);
 		layout_refresh(w, 1);
-	} while (w->active->flags & PANE_HIDDEN);
+	} while (!window_pane_visible(w->active));
 
 	return (0);
 }

cmd-rotate-window.c

@@ -60,7 +60,6 @@ cmd_rotate_window_exec(struct cmd *self, struct cmd_ctx *ctx)
 	struct window		*w;
 	struct window_pane	*wp, *wp2;
 	u_int			 sx, sy, xoff, yoff;
-	int			 flags;
 
 	if ((wl = cmd_find_window(ctx, data->target, NULL)) == NULL)
 		return (-1);
@@ -73,18 +72,13 @@ cmd_rotate_window_exec(struct cmd *self, struct cmd_ctx *ctx)
 
 		xoff = wp->xoff; yoff = wp->yoff;
 		sx = wp->sx; sy = wp->sy;
-		flags = wp->flags;
 		TAILQ_FOREACH(wp, &w->panes, entry) {
 			if ((wp2 = TAILQ_NEXT(wp, entry)) == NULL)
 				break;
 			wp->xoff = wp2->xoff; wp->yoff = wp2->yoff;
-			wp->flags &= ~PANE_HIDDEN;
-			wp->flags |= wp2->flags & PANE_HIDDEN;
 			window_pane_resize(wp, wp2->sx, wp2->sy);
 		}
 		wp->xoff = xoff; wp->yoff = yoff;
-		wp->flags &= ~PANE_HIDDEN;
-		wp->flags |= flags & PANE_HIDDEN;
 		window_pane_resize(wp, sx, sy);
 
 		if ((wp = TAILQ_PREV(w->active, window_panes, entry)) == NULL)
@@ -97,18 +91,13 @@ cmd_rotate_window_exec(struct cmd *self, struct cmd_ctx *ctx)
 
 		xoff = wp->xoff; yoff = wp->yoff;
 		sx = wp->sx; sy = wp->sy;
-		flags = wp->flags;
 		TAILQ_FOREACH_REVERSE(wp, &w->panes, window_panes, entry) {
 			if ((wp2 = TAILQ_PREV(wp, window_panes, entry)) == NULL)
 				break;
 			wp->xoff = wp2->xoff; wp->yoff = wp2->yoff;
-			wp->flags &= ~PANE_HIDDEN;
-			wp->flags |= wp2->flags & PANE_HIDDEN;
 			window_pane_resize(wp, wp2->sx, wp2->sy);
 		}
 		wp->xoff = xoff; wp->yoff = yoff;
-		wp->flags &= ~PANE_HIDDEN;
-		wp->flags |= flags & PANE_HIDDEN;
 		window_pane_resize(wp, sx, sy);
 
 		if ((wp = TAILQ_NEXT(w->active, entry)) == NULL)

cmd-select-pane.c

@@ -58,8 +58,8 @@ cmd_select_pane_exec(struct cmd *self, struct cmd_ctx *ctx)
 		}
 	}
 
-	if (wp->flags & PANE_HIDDEN) {
-		ctx->error(ctx, "pane %d is hidden", data->pane);
+	if (!window_pane_visible(wp)) {
+		ctx->error(ctx, "pane %d is not visible", data->pane);
 		return (-1);
 	}
 	window_set_active_pane(wl->window, wp);

cmd-swap-pane.c

@@ -158,7 +158,6 @@ cmd_swap_pane_exec(struct cmd *self, struct cmd_ctx *ctx)
 	struct window			*w;
 	struct window_pane		*tmp_wp, *src_wp, *dst_wp;
 	u_int				 xx, yy;
-	int				 flags;
 
 	if (data == NULL)
 		return (0);
@@ -210,15 +209,10 @@ cmd_swap_pane_exec(struct cmd *self, struct cmd_ctx *ctx)
 
 	xx = src_wp->xoff;
 	yy = src_wp->yoff;
-	flags = src_wp->flags;
  	src_wp->xoff = dst_wp->xoff;
  	src_wp->yoff = dst_wp->yoff;
-	src_wp->flags &= ~PANE_HIDDEN;
-	src_wp->flags |= dst_wp->flags & PANE_HIDDEN;
  	dst_wp->xoff = xx;
  	dst_wp->yoff = yy;
-	dst_wp->flags &= ~PANE_HIDDEN;
-	dst_wp->flags |= flags & PANE_HIDDEN;
 
 	xx = src_wp->sx;
 	yy = src_wp->sy;
@@ -227,7 +221,7 @@ cmd_swap_pane_exec(struct cmd *self, struct cmd_ctx *ctx)
 
 	if (!data->flag_detached) {
 		tmp_wp = dst_wp;
-		if (tmp_wp->flags & PANE_HIDDEN)
+		if (!window_pane_visible(tmp_wp))
 			tmp_wp = src_wp;
 		window_set_active_pane(w, tmp_wp);
 		layout_refresh(w, 0);

cmd-up-pane.c

@@ -55,7 +55,7 @@ cmd_up_pane_exec(struct cmd *self, struct cmd_ctx *ctx)
 		if (w->active == NULL)
 			w->active = TAILQ_LAST(&w->panes, window_panes);
 		layout_refresh(w, 1);
-	} while (w->active->flags & PANE_HIDDEN);
+	} while (!window_pane_visible(w->active));
 
 	return (0);
 }

layout-manual.c

@@ -26,7 +26,7 @@ void
 layout_manual_v_refresh(struct window *w, unused int active_only)
 {
 	struct window_pane	*wp;
-	u_int			 npanes, canfit, total;
+	u_int			 npanes, total, height;
 	int			 left;
 
 	if (active_only)
@@ -35,34 +35,25 @@ layout_manual_v_refresh(struct window *w, unused int active_only)
 	if (TAILQ_EMPTY(&w->panes))
 		return;
 
-	/* Clear hidden flags. */
-	TAILQ_FOREACH(wp, &w->panes, entry)
-	    	wp->flags &= ~PANE_HIDDEN;
-
 	/* Check the new size. */
 	npanes = window_count_panes(w);
 	if (w->sy <= PANE_MINIMUM * npanes) {
-		/* How many can we fit? */
-		canfit = w->sy / PANE_MINIMUM;
-		if (canfit == 0) {
-			/* None. Just use this size for the first. */
-			TAILQ_FOREACH(wp, &w->panes, entry) {
-				if (wp == TAILQ_FIRST(&w->panes))
-					wp->sy = w->sy;
-				else
-					wp->flags |= PANE_HIDDEN;
-			}
-		} else {
-			/* >=1, set minimum for them all. */
-			TAILQ_FOREACH(wp, &w->panes, entry) {
-				if (canfit-- > 0)
-					wp->sy = PANE_MINIMUM - 1;
-				else
-					wp->flags |= PANE_HIDDEN;
-			}
-			/* And increase the first by the rest. */
-			TAILQ_FIRST(&w->panes)->sy += 1 + w->sy % PANE_MINIMUM;
+		/* 
+		 * Make the first pane the smaller of the minimum and total (it
+		 * must fit to be visible) and the rest the minimum size.
+		 */
+		height = PANE_MINIMUM;
+		if (height > w->sy)
+			height = w->sy + 1;
+		TAILQ_FOREACH(wp, &w->panes, entry) {
+			if (wp == TAILQ_FIRST(&w->panes))
+				wp->sy = height - 1;
+			else
+				wp->sy = PANE_MINIMUM - 1;
 		}
+		/* And increase the first by the rest if possible. */
+		if (w->sy >= PANE_MINIMUM)
+			TAILQ_FIRST(&w->panes)->sy += 1 + w->sy % PANE_MINIMUM;
 	} else {
 		/* In theory they will all fit. Find the current total. */
 		total = 0;
@@ -174,8 +165,6 @@ layout_manual_v_update_offsets(struct window *w)
 
 	yoff = 0;
 	TAILQ_FOREACH(wp, &w->panes, entry) {
-		if (wp->flags & PANE_HIDDEN)
-			continue;
 		wp->xoff = 0;
 		wp->yoff = yoff;
 		yoff += wp->sy + 1;

layout.c

@@ -125,14 +125,19 @@ void
 layout_active_only_refresh(struct window *w, unused int active_only)
 {
 	struct window_pane	*wp;
+	u_int			 xoff;
 
+	xoff = w->sx;
 	TAILQ_FOREACH(wp, &w->panes, entry) {
-		if (wp == w->active) {
-			wp->flags &= ~PANE_HIDDEN;
-			wp->xoff = wp->yoff = 0;
-			window_pane_resize(wp, w->sx, w->sy);
-		} else
-			wp->flags |= PANE_HIDDEN;
+		/* Put the active pane on screen and the rest to the right. */
+		if (wp == w->active)
+			wp->xoff = 0;
+		else {
+			wp->xoff = xoff;
+			xoff += w->sx;
+		}
+		wp->yoff = 0;
+		window_pane_resize(wp, w->sx, w->sy);
 	}
 }
 
@@ -145,6 +150,12 @@ layout_even_h_refresh(struct window *w, int active_only)
 	if (active_only)
 		return;
 
+	/* If the screen is too small, show active only. */
+	if (w->sx < PANE_MINIMUM || w->sy < PANE_MINIMUM) {
+		layout_active_only_refresh(w, active_only);
+		return;
+	}
+
 	/* Get number of panes. */
 	n = window_count_panes(w);
 	if (n == 0)
@@ -153,19 +164,13 @@ layout_even_h_refresh(struct window *w, int active_only)
 	/* How many can we fit? */
 	if (w->sx / n < PANE_MINIMUM) {
 		width = PANE_MINIMUM;
-		n = w->sx / PANE_MINIMUM;
+		n = UINT_MAX;
 	} else
 		width = w->sx / n;
 
 	/* Fit the panes. */
 	i = xoff = 0;
 	TAILQ_FOREACH(wp, &w->panes, entry) {
-		if (i > n) {
-			wp->flags |= PANE_HIDDEN;
-			continue;
-		}
-		wp->flags &= ~PANE_HIDDEN;
-
 		wp->xoff = xoff;
 		wp->yoff = 0;
 		if (i != n - 1)
@@ -193,6 +198,12 @@ layout_even_v_refresh(struct window *w, int active_only)
 	if (active_only)
 		return;
 
+	/* If the screen is too small, show active only. */
+	if (w->sx < PANE_MINIMUM || w->sy < PANE_MINIMUM) {
+		layout_active_only_refresh(w, active_only);
+		return;
+	}
+
 	/* Get number of panes. */
 	n = window_count_panes(w);
 	if (n == 0)
@@ -201,19 +212,13 @@ layout_even_v_refresh(struct window *w, int active_only)
 	/* How many can we fit? */
 	if (w->sy / n < PANE_MINIMUM) {
 		height = PANE_MINIMUM;
-		n = w->sy / PANE_MINIMUM;
+		n = UINT_MAX;
 	} else
 		height = w->sy / n;
 
 	/* Fit the panes. */
 	i = yoff = 0;
 	TAILQ_FOREACH(wp, &w->panes, entry) {
-		if (i > n) {
-			wp->flags |= PANE_HIDDEN;
-			continue;
-		}
-		wp->flags &= ~PANE_HIDDEN;
-
 		wp->xoff = 0;
 		wp->yoff = yoff;
 		if (i != n - 1)
@@ -250,7 +255,8 @@ layout_main_v_refresh(struct window *w, int active_only)
 	mainwidth = options_get_number(&w->options, "main-pane-width") + 1;
 
 	/* Need >1 pane and minimum columns; if fewer, display active only. */
-	if (n == 1 || w->sx < mainwidth + PANE_MINIMUM) {
+	if (n == 1 ||
+	    w->sx < mainwidth + PANE_MINIMUM || w->sy < PANE_MINIMUM) {
 		layout_active_only_refresh(w, active_only);
 		return;
 	}
@@ -270,16 +276,9 @@ layout_main_v_refresh(struct window *w, int active_only)
 			wp->xoff = 0;
 			wp->yoff = 0;
 			window_pane_resize(wp, mainwidth - 1, w->sy);
-			wp->flags &= ~PANE_HIDDEN;
 			continue;
 		}
 
-		if (i > n) {
-			wp->flags |= PANE_HIDDEN;
-			continue;
-		}
-		wp->flags &= ~PANE_HIDDEN;
-
 		wp->xoff = mainwidth;
 		wp->yoff = yoff;
 		if (i != n - 1)
@@ -320,7 +319,8 @@ layout_main_h_refresh(struct window *w, int active_only)
 	mainheight = options_get_number(&w->options, "main-pane-height") + 1;
 
 	/* Need >1 pane and minimum rows; if fewer, display active only. */
-	if (n == 1 || w->sy < mainheight + PANE_MINIMUM) {
+	if (n == 1 ||
+	    w->sy < mainheight + PANE_MINIMUM || w->sx < PANE_MINIMUM) {
 		layout_active_only_refresh(w, active_only);
 		return;
 	}
@@ -340,16 +340,9 @@ layout_main_h_refresh(struct window *w, int active_only)
 			wp->xoff = 0;
 			wp->yoff = 0;
 			window_pane_resize(wp, w->sx, mainheight - 1);
-			wp->flags &= ~PANE_HIDDEN;
 			continue;
 		}
 
-		if (i > n) {
-			wp->flags |= PANE_HIDDEN;
-			continue;
-		}
-		wp->flags &= ~PANE_HIDDEN;
-
 		wp->xoff = xoff;
 		wp->yoff = mainheight;
 		if (i != n - 1)

resize.c

@@ -48,6 +48,7 @@ recalculate_sizes(void)
 	struct session		*s;
 	struct client		*c;
 	struct window		*w;
+	struct window_pane	*wp;
 	u_int		 	 i, j, ssx, ssy, has, limit;
 	int		 	 flag;
 
@@ -132,6 +133,20 @@ recalculate_sizes(void)
 		    "window size %u,%u (was %u,%u)", ssx, ssy, w->sx, w->sy);
 
 		window_resize(w, ssx, ssy);
+
+		/*
+		 * If the current pane is now not visible, move to the next
+		 * that is.
+		 */
+		wp = w->active;
+		while (!window_pane_visible(w->active)) {
+			w->active = TAILQ_PREV(w->active, window_panes, entry);
+			if (w->active == NULL)
+				w->active = TAILQ_LAST(&w->panes, window_panes);
+			if (w->active == wp)
+			       break;
+		}
+
 		server_redraw_window(w);
 		layout_refresh(w, 0);
 	}

screen-redraw.c

@@ -35,6 +35,9 @@ screen_redraw_check_cell(struct client *c, u_int px, u_int py)
 		return (0);
 
 	TAILQ_FOREACH(wp, &w->panes, entry) {
+		if (!window_pane_visible(wp))
+			continue;
+
 		/* Inside pane. */
 		if (px >= wp->xoff && px < wp->xoff + wp->sx &&
 		    py >= wp->yoff && py < wp->yoff + wp->sy)
@@ -104,7 +107,7 @@ screen_redraw_screen(struct client *c)
 
 	/* Draw the panes. */
 	TAILQ_FOREACH(wp, &w->panes, entry) {
-		if (wp->flags & PANE_HIDDEN)
+		if (!window_pane_visible(wp))
 			continue;
 
 		tty_reset(tty);

tmux.h

@@ -48,7 +48,7 @@ extern const char    *__progname;
 #define PROMPT_HISTORY 100
 
 /* Minimum pane size. */
-#define PANE_MINIMUM 4	/* includes separator line */
+#define PANE_MINIMUM 5	/* includes separator line */
 
 /* Automatic name refresh interval, in milliseconds. */
 #define NAME_INTERVAL 500
@@ -600,8 +600,7 @@ struct window_pane {
 	u_int		 yoff;
 
 	int		 flags;
-#define PANE_HIDDEN 0x1
-#define PANE_REDRAW 0x2
+#define PANE_REDRAW 0x1
 
 	char		*cmd;
 	char		*cwd;
@@ -1454,6 +1453,7 @@ void		 window_pane_parse(struct window_pane *);
 void		 window_pane_key(struct window_pane *, struct client *, int);
 void		 window_pane_mouse(struct window_pane *,
     		     struct client *, u_char, u_char, u_char);
+int		 window_pane_visible(struct window_pane *);
 char		*window_pane_search(
 		     struct window_pane *, const char *, u_int *);
 

tty-write.c

@@ -44,7 +44,7 @@ tty_vwrite_cmd(struct window_pane *wp, enum tty_cmd cmd, va_list ap)
 
 	if (wp->window->flags & WINDOW_REDRAW || wp->flags & PANE_REDRAW)
 		return;
-	if (wp->window->flags & WINDOW_HIDDEN || wp->flags & PANE_HIDDEN)
+	if (wp->window->flags & WINDOW_HIDDEN || !window_pane_visible(wp))
 		return;
 
 	for (i = 0; i < ARRAY_LENGTH(&clients); i++) {

window.c

@@ -291,8 +291,14 @@ void
 window_set_active_pane(struct window *w, struct window_pane *wp)
 {
 	w->active = wp;
-	while (w->active->flags & PANE_HIDDEN)
+
+	while (!window_pane_visible(w->active)) {
 		w->active = TAILQ_PREV(w->active, window_panes, entry);
+		if (w->active == NULL)
+			w->active = TAILQ_LAST(&w->panes, window_panes);
+		if (w->active == wp)
+			return;
+	}
 }
 
 struct window_pane *
@@ -607,6 +613,18 @@ window_pane_mouse(
 		input_mouse(wp, b, x, y);
 }
 
+int
+window_pane_visible(struct window_pane *wp)
+{
+	struct window	*w = wp->window;
+
+	if (wp->xoff >= w->sx || wp->yoff >= w->sy)
+		return (0);
+	if (wp->xoff + wp->sx > w->sx || wp->yoff + wp->sy > w->sy)
+		return (0);
+	return (1);
+}
+
 char *
 window_pane_search(struct window_pane *wp, const char *searchstr, u_int *lineno)
 {