From 35709a30ee7ff18b7cb4092ec52d063be8724c51 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Sat, 6 Jun 2026 17:30:48 +0000
Subject: [PATCH] Change so that floating panes are always part of the root
 layout. From Dane Jensen.

---
 cmd-split-window.c |   2 +-
 layout.c           | 141 +++++++++++++++++++++++++++++----------------
 tmux.h             |  10 ++--
 3 files changed, 96 insertions(+), 57 deletions(-)

diff --git a/cmd-split-window.c b/cmd-split-window.c
index 1d8fa08d..59239ee8 100644
--- a/cmd-split-window.c
+++ b/cmd-split-window.c
@@ -105,7 +105,7 @@ cmd_split_window_exec(struct cmd *self, struct cmdq_item *item)
 		flags |= SPAWN_EMPTY;
 
 	if (is_floating)
-		lc = layout_get_floating_cell(item, args, w, wp, lc, &cause);
+		lc = layout_get_floating_cell(item, args, w, wp, &cause);
 	else
 		lc = layout_get_tiled_cell(item, args, w, wp, flags, &cause);
 	if (cause != NULL) {
diff --git a/layout.c b/layout.c
index 5cdb4134..c5b457ff 100644
--- a/layout.c
+++ b/layout.c
@@ -46,8 +46,6 @@ static int	layout_set_size_check(struct window *, struct layout_cell *,
 		    enum layout_type, int);
 static void	layout_resize_child_cells(struct window *,
 		    struct layout_cell *);
-void		layout_redistribute_cells(struct window *, struct layout_cell *,
-		    enum layout_type);
 
 /* Create a new layout cell. */
 struct layout_cell *
@@ -252,6 +250,8 @@ layout_fix_offsets1(struct layout_cell *lc)
 	if (lc->type == LAYOUT_LEFTRIGHT) {
 		xoff = lc->xoff;
 		TAILQ_FOREACH(lcchild, &lc->cells, entry) {
+			if (lcchild->flags & LAYOUT_CELL_FLOATING)
+				continue;
 			lcchild->xoff = xoff;
 			lcchild->yoff = lc->yoff;
 			if (lcchild->type != LAYOUT_WINDOWPANE)
@@ -261,6 +261,8 @@ layout_fix_offsets1(struct layout_cell *lc)
 	} else {
 		yoff = lc->yoff;
 		TAILQ_FOREACH(lcchild, &lc->cells, entry) {
+			if (lcchild->flags & LAYOUT_CELL_FLOATING)
+				continue;
 			lcchild->xoff = lc->xoff;
 			lcchild->yoff = yoff;
 			if (lcchild->type != LAYOUT_WINDOWPANE)
@@ -276,6 +278,10 @@ layout_fix_offsets(struct window *w)
 {
 	struct layout_cell	*lc = w->layout_root;
 
+	/* Root consists of a single floating cell */
+	if (lc->flags & LAYOUT_CELL_FLOATING)
+		return;
+
 	lc->xoff = 0;
 	lc->yoff = 0;
 
@@ -484,8 +490,11 @@ layout_resize_adjust(struct window *w, struct layout_cell *lc,
 
 	/* Child cell runs in a different direction. */
 	if (lc->type != type) {
-		TAILQ_FOREACH(lcchild, &lc->cells, entry)
+		TAILQ_FOREACH(lcchild, &lc->cells, entry) {
+			if (lcchild->flags & LAYOUT_CELL_FLOATING)
+				continue;
 			layout_resize_adjust(w, lcchild, type, change);
+		}
 		return;
 	}
 
@@ -497,6 +506,8 @@ layout_resize_adjust(struct window *w, struct layout_cell *lc,
 		TAILQ_FOREACH(lcchild, &lc->cells, entry) {
 			if (change == 0)
 				break;
+			if (lcchild->flags & LAYOUT_CELL_FLOATING)
+				continue;
 			if (change > 0) {
 				layout_resize_adjust(w, lcchild, type, 1);
 				change--;
@@ -515,30 +526,33 @@ void
 layout_destroy_cell(struct window *w, struct layout_cell *lc,
     struct layout_cell **lcroot)
 {
-	struct layout_cell     *lcother, *lcparent;
+	struct layout_cell     *lcother = NULL, *lcparent;
 
-	/*
-	 * If no parent, this is either a floating pane or the last
-	 * pane so window close is imminent and there is no need to
-	 * resize anything.
-	 */
+	/* If no parent, this is the last pane in a window. */
 	lcparent = lc->parent;
 	if (lcparent == NULL) {
-		if (lc->wp != NULL && !window_pane_is_floating(lc->wp))
+		if (lc->wp != NULL)
 			*lcroot = NULL;
 		layout_free_cell(lc);
 		return;
 	}
 
-	/* Merge the space into the previous or next cell. */
-	if (lc == TAILQ_FIRST(&lcparent->cells))
-		lcother = TAILQ_NEXT(lc, entry);
-	else
-		lcother = TAILQ_PREV(lc, layout_cells, entry);
-	if (lcother != NULL && lcparent->type == LAYOUT_LEFTRIGHT)
-		layout_resize_adjust(w, lcother, lcparent->type, lc->sx + 1);
-	else if (lcother != NULL)
-		layout_resize_adjust(w, lcother, lcparent->type, lc->sy + 1);
+	if (~lc->flags & LAYOUT_CELL_FLOATING) {
+		/* Merge the space into the previous or next cell. */
+		if (lc == TAILQ_FIRST(&lcparent->cells))
+			lcother = TAILQ_NEXT(lc, entry);
+		else
+			lcother = TAILQ_PREV(lc, layout_cells, entry);
+	}
+	if (lcother != NULL && (~lcother->flags & LAYOUT_CELL_FLOATING)) {
+		if (lcparent->type == LAYOUT_LEFTRIGHT) {
+			layout_resize_adjust(w, lcother, lcparent->type,
+			    lc->sx + 1);
+		} else {
+			layout_resize_adjust(w, lcother, lcparent->type,
+			    lc->sy + 1);
+		}
+	}
 
 	/* Remove this from the parent's list. */
 	TAILQ_REMOVE(&lcparent->cells, lc, entry);
@@ -554,8 +568,10 @@ layout_destroy_cell(struct window *w, struct layout_cell *lc,
 
 		lc->parent = lcparent->parent;
 		if (lc->parent == NULL) {
-			lc->xoff = 0;
-			lc->yoff = 0;
+			if (~lc->flags & LAYOUT_CELL_FLOATING) {
+				lc->xoff = 0;
+				lc->yoff = 0;
+			}
 			*lcroot = lc;
 		} else
 			TAILQ_REPLACE(&lc->parent->cells, lcparent, lc, entry);
@@ -603,6 +619,8 @@ layout_resize(struct window *w, u_int sx, u_int sy)
 	 * out proportionately - this should leave the layout fitting the new
 	 * window size.
 	 */
+	if (lc->type == LAYOUT_WINDOWPANE && (lc->flags & LAYOUT_CELL_FLOATING))
+		return;
 	xchange = sx - lc->sx;
 	xlimit = layout_resize_check(w, lc, LAYOUT_LEFTRIGHT);
 	if (xchange < 0 && xchange < -xlimit)
@@ -915,6 +933,8 @@ layout_resize_child_cells(struct window *w, struct layout_cell *lc)
 	count = 0;
 	previous = 0;
 	TAILQ_FOREACH(lcchild, &lc->cells, entry) {
+		if (lcchild->flags & LAYOUT_CELL_FLOATING)
+			continue;
 		count++;
 		if (lc->type == LAYOUT_LEFTRIGHT)
 			previous += lcchild->sx;
@@ -933,6 +953,8 @@ layout_resize_child_cells(struct window *w, struct layout_cell *lc)
 	/* Resize children into the new size. */
 	idx = 0;
 	TAILQ_FOREACH(lcchild, &lc->cells, entry) {
+		if (lcchild->flags & LAYOUT_CELL_FLOATING)
+			continue;
 		if (lc->type == LAYOUT_TOPBOTTOM) {
 			lcchild->sx = lc->sx;
 			lcchild->xoff = lc->xoff;
@@ -941,9 +963,10 @@ layout_resize_child_cells(struct window *w, struct layout_cell *lc)
 			    lc->type, lc->sx, count - idx, available);
 			available -= (lcchild->sx + 1);
 		}
-		if (lc->type == LAYOUT_LEFTRIGHT)
+		if (lc->type == LAYOUT_LEFTRIGHT) {
 			lcchild->sy = lc->sy;
-		else {
+			lcchild->yoff = lc->yoff;
+		} else {
 			lcchild->sy = layout_new_pane_size(w, previous, lcchild,
 			    lc->type, lc->sy, count - idx, available);
 			available -= (lcchild->sy + 1);
@@ -1132,6 +1155,39 @@ layout_split_pane(struct window_pane *wp, enum layout_type type, int size,
 	return (lcnew);
 }
 
+/*
+ * Creates a cell for a new floating pane. This must be followed by
+ * layout_assign_pane before much else happens!
+ */
+struct layout_cell *
+layout_floating_pane(struct window *w, u_int sx, u_int sy, int ox, int oy)
+{
+	struct layout_cell	*lc = w->layout_root, *lcnew, *lcparent;
+
+	if (lc->type == LAYOUT_WINDOWPANE) {
+		/*
+		* Adding a pane to a root that doesn't have a container. Must
+		* create and insert a new root.
+		*/
+		lcparent = layout_create_cell(NULL);
+		layout_make_node(lcparent, LAYOUT_TOPBOTTOM);
+		layout_set_size(lcparent, w->sx, w->sy, 0, 0);
+		w->layout_root = lcparent;
+
+		/* Insert the old cell. */
+		lc->parent = lcparent;
+		TAILQ_INSERT_HEAD(&lcparent->cells, lc, entry);
+	} else
+		lcparent = w->layout_root;
+
+	lcnew = layout_create_cell(lcparent);
+	TAILQ_INSERT_TAIL(&lcparent->cells, lcnew, entry);
+	lcnew->flags |= LAYOUT_CELL_FLOATING;
+	layout_set_size(lcnew, sx, sy, ox, oy);
+
+	return (lcnew);
+}
+
 /* Destroy the cell associated with a pane. */
 void
 layout_close_pane(struct window_pane *wp)
@@ -1143,6 +1199,7 @@ layout_close_pane(struct window_pane *wp)
 
 	/* Remove the cell. */
 	layout_destroy_cell(w, wp->layout_cell, &w->layout_root);
+	wp->layout_cell = NULL;
 
 	/* Fix pane offsets and sizes. */
 	if (w->layout_root != NULL) {
@@ -1299,49 +1356,37 @@ layout_get_tiled_cell(struct cmdq_item *item, struct args *args,
 /* Get a new floating cell. */
 struct layout_cell *
 layout_get_floating_cell(struct cmdq_item *item, struct args *args,
-    struct window *w, __unused struct window_pane *wp, struct layout_cell *lc,
-    char **cause)
+    struct window *w, __unused struct window_pane *wp, char **cause)
 {
-	u_int	sx, sy, ox, oy;
-	int	new = 0;
-
-	if (lc == NULL) {
-		lc = layout_create_cell(NULL);
-		new = 1;
-	}
-
-	sx = lc->sx; sy = lc->sy;
-	ox = lc->xoff; oy = lc->yoff;
+	struct layout_cell	*lcnew;
+	u_int			 sx = w->sx / 2, sy = w->sy / 4;
+	int			 ox = INT_MAX, oy = INT_MAX;
 
 	if (args_has(args, 'x')) {
 		sx = args_percentage_and_expand(args, 'x', 0, USHRT_MAX, w->sx,
 		    item, cause);
 		if (*cause != NULL)
-			goto error;
+			return (NULL);
 	}
 	if (args_has(args, 'y')) {
 		sy = args_percentage_and_expand(args, 'y', 0, USHRT_MAX, w->sy,
 		    item, cause);
 		if (*cause != NULL)
-			goto error;
+			return (NULL);
 	}
 	if (args_has(args, 'X')) {
 		ox = args_percentage_and_expand(args, 'X', 0, USHRT_MAX, w->sx,
 		    item, cause);
 		if (*cause != NULL)
-			goto error;
+			return (NULL);
 	}
 	if (args_has(args, 'Y')) {
 		oy = args_percentage_and_expand(args, 'Y', 0, USHRT_MAX, w->sy,
 		    item, cause);
 		if (*cause != NULL)
-			goto error;
+			return (NULL);
 	}
 
-	if (sx == UINT_MAX)
-		sx = w->sx / 2;
-	if (sy == UINT_MAX)
-		sy = w->sy / 4;
 	if (ox == INT_MAX) {
 		if (w->last_new_pane_x == 0)
 			ox = 4;
@@ -1362,13 +1407,7 @@ layout_get_floating_cell(struct cmdq_item *item, struct args *args,
 		}
 		w->last_new_pane_y = oy;
 	}
-	layout_set_size(lc, sx, sy, ox, oy);
-	lc->flags |= LAYOUT_CELL_FLOATING;
 
-	return (lc);
-
-error:
-	if (new)
-		layout_destroy_cell(w, lc, &w->layout_root);
-	return (NULL);
+	lcnew = layout_floating_pane(w, sx, sy, ox, oy);
+	return (lcnew);
 }
diff --git a/tmux.h b/tmux.h
index 524748ae..7f0e438a 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1235,7 +1235,7 @@ struct window_pane {
 #define PANE_FOCUSED 0x4
 #define PANE_VISITED 0x8
 #define PANE_ZOOMED 0x10
-/* unused 0x20 */
+/* 0x20 unused */
 #define PANE_INPUTOFF 0x40
 #define PANE_CHANGED 0x80
 #define PANE_EXITED 0x100
@@ -1439,8 +1439,7 @@ TAILQ_HEAD(layout_cells, layout_cell);
 struct layout_cell {
 	enum layout_type type;
 
-/* unused 0x1 */
-#define LAYOUT_CELL_FLOATING 0x2
+#define LAYOUT_CELL_FLOATING 0x1
 	int		 flags;
 
 	struct layout_cell *parent;
@@ -3481,12 +3480,13 @@ void		 layout_assign_pane(struct layout_cell *, struct window_pane *,
 		     int);
 struct layout_cell *layout_split_pane(struct window_pane *, enum layout_type,
 		     int, int);
+struct layout_cell *layout_floating_pane(struct window *, u_int, u_int, int,
+		     int);
 void		 layout_close_pane(struct window_pane *);
 int		 layout_spread_cell(struct window *, struct layout_cell *);
 void		 layout_spread_out(struct window_pane *);
 struct layout_cell *layout_get_floating_cell(struct cmdq_item *, struct args *,
-		     struct window *, struct window_pane *, struct layout_cell *,
-		     char **);
+		     struct window *, struct window_pane *, char **);
 struct layout_cell *layout_get_tiled_cell(struct cmdq_item *, struct args *,
 		     struct window *, struct window_pane *, int, char **);