Merge pull request #2072 from RyanDwyer/atomic

Atomic layout updates

include/sway/desktop/transaction.h

@@ -0,0 +1,67 @@
+#ifndef _SWAY_TRANSACTION_H
+#define _SWAY_TRANSACTION_H
+#include <wlr/render/wlr_texture.h>
+#include "sway/tree/container.h"
+
+/**
+ * Transactions enable us to perform atomic layout updates.
+ *
+ * When we want to make adjustments to the layout, we create a transaction.
+ * A transaction contains a list of affected containers and their new state.
+ * A state might contain a new size, or new border settings, or new parent/child
+ * relationships.
+ *
+ * Calling transaction_commit() makes sway notify of all the affected clients
+ * with their new sizes. We then wait for all the views to respond with their
+ * new surface sizes. When all are ready, or when a timeout has passed, we apply
+ * the updates all at the same time.
+ */
+
+struct sway_transaction;
+
+/**
+ * Create a new transaction.
+ */
+struct sway_transaction *transaction_create(void);
+
+/**
+ * Add a container's pending state to the transaction.
+ */
+void transaction_add_container(struct sway_transaction *transaction,
+		struct sway_container *container);
+
+/**
+ * Submit a transaction to the client views for configuration.
+ */
+void transaction_commit(struct sway_transaction *transaction);
+
+/**
+ * Notify the transaction system that a view is ready for the new layout.
+ *
+ * When all views in the transaction are ready, the layout will be applied.
+ */
+void transaction_notify_view_ready(struct sway_view *view, uint32_t serial);
+
+/**
+ * Notify the transaction system that a view is ready for the new layout, but
+ * identifying the instruction by width and height rather than by serial.
+ *
+ * This is used by xwayland views, as they don't have serials.
+ */
+void transaction_notify_view_ready_by_size(struct sway_view *view,
+		int width, int height);
+
+/**
+ * Get the saved texture that should be rendered for a view.
+ *
+ * The addresses pointed at by the width and height pointers will be populated
+ * with the surface's dimensions, which may be different to the texture's
+ * dimensions if output scaling is used.
+ *
+ * This function should only be called if it is known that the view has
+ * instructions.
+ */
+struct wlr_texture *transaction_get_saved_texture(struct sway_view *view,
+		int *width, int *height);
+
+#endif

include/sway/input/seat.h

@@ -118,6 +118,17 @@ struct sway_container *seat_get_focus_inactive_view(struct sway_seat *seat,
 struct sway_container *seat_get_active_child(struct sway_seat *seat,
 		struct sway_container *container);
 
+/**
+ * Return the immediate child of container which was most recently focused, with
+ * fallback to selecting the child in the parent's `current` (rendered) children
+ * list.
+ *
+ * This is useful for when a tabbed container and its children are destroyed but
+ * still being rendered, and we have to render an appropriate child.
+ */
+struct sway_container *seat_get_active_current_child(struct sway_seat *seat,
+		struct sway_container *container);
+
 /**
  * Iterate over the focus-inactive children of the container calling the
  * function on each.

include/sway/output.h

@@ -46,6 +46,8 @@ void output_damage_surface(struct sway_output *output, double ox, double oy,
 void output_damage_from_view(struct sway_output *output,
 	struct sway_view *view);
 
+void output_damage_box(struct sway_output *output, struct wlr_box *box);
+
 void output_damage_whole_container(struct sway_output *output,
 	struct sway_container *con);
 

include/sway/server.h

@@ -11,6 +11,7 @@
 #include <wlr/types/wlr_xdg_shell.h>
 #include <wlr/render/wlr_renderer.h>
 // TODO WLR: make Xwayland optional
+#include "list.h"
 #include "sway/xwayland.h"
 
 struct sway_server {
@@ -40,6 +41,14 @@ struct sway_server {
 	struct sway_xwayland xwayland;
 	struct wl_listener xwayland_surface;
 	struct wl_listener xwayland_ready;
+
+	bool debug_txn_timings;
+
+	list_t *transactions;
+
+	// When a view is being destroyed and is waiting for a transaction to
+	// complete it will be stored here.
+	list_t *destroying_containers;
 };
 
 struct sway_server server;

include/sway/tree/arrange.h

@@ -1,5 +1,6 @@
 #ifndef _SWAY_ARRANGE_H
 #define _SWAY_ARRANGE_H
+#include "sway/desktop/transaction.h"
 
 struct sway_container;
 
@@ -9,16 +10,27 @@ void remove_gaps(struct sway_container *c);
 // Add gaps around container
 void add_gaps(struct sway_container *c);
 
-// Determine the root container's geometry, then iterate to everything below
+/**
-void arrange_root(void);
+ * Arrange layout for all the children of the given container, and add them to
+ * the given transaction.
+ *
+ * Use this function if you need to arrange multiple sections of the tree in one
+ * transaction.
+ *
+ * You must set the desired state of the container before calling
+ * arrange_windows, then don't change any state-tracked properties in the
+ * container until you've called transaction_commit.
+ */
+void arrange_windows(struct sway_container *container,
+		struct sway_transaction *transaction);
 
-// Determine the output's geometry, then iterate to everything below
+/**
-void arrange_output(struct sway_container *output);
+ * Arrange layout for the given container and commit the transaction.
-
+ *
-// Determine the workspace's geometry, then iterate to everything below
+ * This function is a wrapper around arrange_windows, and handles creating and
-void arrange_workspace(struct sway_container *workspace);
+ * committing the transaction for you. Use this function if you're only doing
-
+ * one arrange operation.
-// Arrange layout for all the children of the given workspace/container
+ */
-void arrange_children_of(struct sway_container *parent);
+void arrange_and_commit(struct sway_container *container);
 
 #endif

include/sway/tree/container.h

@@ -54,6 +54,37 @@ struct sway_output;
 struct sway_workspace;
 struct sway_view;
 
+struct sway_container_state {
+	// Container/swayc properties
+	enum sway_container_layout layout;
+	double swayc_x, swayc_y;
+	double swayc_width, swayc_height;
+
+	bool has_gaps;
+	double current_gaps;
+	double gaps_inner;
+	double gaps_outer;
+
+	struct sway_container *parent;
+	list_t *children;
+
+	// View properties
+	double view_x, view_y;
+	double view_width, view_height;
+	bool is_fullscreen;
+
+	enum sway_container_border border;
+	int border_thickness;
+	bool border_top;
+	bool border_bottom;
+	bool border_left;
+	bool border_right;
+
+	// Workspace properties
+	struct sway_view *ws_fullscreen;
+	struct sway_container *ws_floating;
+};
+
 struct sway_container {
 	union {
 		// TODO: Encapsulate state for other node types as well like C_CONTAINER
@@ -69,6 +100,10 @@ struct sway_container {
 	 */
 	size_t id;
 
+	// The pending state is the main container properties, and the current state is in the below struct.
+	// This means most places of the code can refer to the main variables (pending state) and it'll just work.
+	struct sway_container_state current;
+
 	char *name;            // The view's title (unformatted)
 	char *formatted_title; // The title displayed in the title bar
 
@@ -97,8 +132,6 @@ struct sway_container {
 
 	struct sway_container *parent;
 
-	list_t *marks; // list of char*
-
 	float alpha;
 
 	struct wlr_texture *title_focused;
@@ -107,6 +140,10 @@ struct sway_container {
 	struct wlr_texture *title_urgent;
 	size_t title_height;
 
+	list_t *instructions; // struct sway_transaction_instruction *
+
+	bool destroying;
+
 	struct {
 		struct wl_signal destroy;
 		// Raised after the tree updates, but before arrange_windows
@@ -150,6 +187,8 @@ struct sway_container *workspace_create(struct sway_container *output,
 struct sway_container *container_view_create(
 		struct sway_container *sibling, struct sway_view *sway_view);
 
+void container_free(struct sway_container *cont);
+
 struct sway_container *container_destroy(struct sway_container *container);
 
 struct sway_container *container_close(struct sway_container *container);
@@ -253,4 +292,9 @@ void container_set_geometry_from_floating_view(struct sway_container *con);
  */
 bool container_is_floating(struct sway_container *container);
 
+/**
+ * Get a container's box in layout coordinates.
+ */
+void container_get_box(struct sway_container *container, struct wlr_box *box);
+
 #endif

include/sway/tree/view.h

@@ -29,8 +29,8 @@ struct sway_view_impl {
 	const char *(*get_string_prop)(struct sway_view *view,
 			enum sway_view_prop prop);
 	uint32_t (*get_int_prop)(struct sway_view *view, enum sway_view_prop prop);
-	void (*configure)(struct sway_view *view, double lx, double ly, int width,
+	uint32_t (*configure)(struct sway_view *view, double lx, double ly,
-		int height);
+			int width, int height);
 	void (*set_activated)(struct sway_view *view, bool activated);
 	void (*set_tiled)(struct sway_view *view, bool tiled);
 	void (*set_fullscreen)(struct sway_view *view, bool fullscreen);
@@ -69,6 +69,8 @@ struct sway_view {
 	bool border_left;
 	bool border_right;
 
+	bool destroying;
+
 	list_t *executed_criteria; // struct criteria *
 	list_t *marks;             // char *
 
@@ -104,8 +106,6 @@ struct sway_xdg_shell_v6_view {
 	struct wl_listener map;
 	struct wl_listener unmap;
 	struct wl_listener destroy;
-
-	int pending_width, pending_height;
 };
 
 struct sway_xdg_shell_view {
@@ -120,8 +120,6 @@ struct sway_xdg_shell_view {
 	struct wl_listener map;
 	struct wl_listener unmap;
 	struct wl_listener destroy;
-
-	int pending_width, pending_height;
 };
 
 struct sway_xwayland_view {
@@ -139,9 +137,6 @@ struct sway_xwayland_view {
 	struct wl_listener map;
 	struct wl_listener unmap;
 	struct wl_listener destroy;
-
-	int pending_lx, pending_ly;
-	int pending_width, pending_height;
 };
 
 struct sway_xwayland_unmanaged {
@@ -213,9 +208,14 @@ uint32_t view_get_window_type(struct sway_view *view);
 
 const char *view_get_shell(struct sway_view *view);
 
-void view_configure(struct sway_view *view, double ox, double oy, int width,
+uint32_t view_configure(struct sway_view *view, double lx, double ly, int width,
 	int height);
 
+/**
+ * Center the view in its workspace and build the swayc decorations around it.
+ */
+void view_init_floating(struct sway_view *view);
+
 /**
  * Configure the view's position and size based on the swayc's position and
  * size, taking borders into consideration.
@@ -242,6 +242,8 @@ void view_for_each_surface(struct sway_view *view,
 void view_init(struct sway_view *view, enum sway_view_type type,
 	const struct sway_view_impl *impl);
 
+void view_free(struct sway_view *view);
+
 void view_destroy(struct sway_view *view);
 
 void view_map(struct sway_view *view, struct wlr_surface *wlr_surface);

sway/commands/border.c

@@ -3,6 +3,7 @@
 #include "sway/config.h"
 #include "sway/input/cursor.h"
 #include "sway/input/input-manager.h"
+#include "sway/tree/arrange.h"
 #include "sway/tree/container.h"
 #include "sway/tree/view.h"
 
@@ -38,13 +39,11 @@ struct cmd_results *cmd_border(int argc, char **argv) {
 	}
 
 	if (container_is_floating(view->swayc)) {
-		container_damage_whole(view->swayc);
 		container_set_geometry_from_floating_view(view->swayc);
-		container_damage_whole(view->swayc);
-	} else {
-		view_autoconfigure(view);
 	}
 
+	arrange_and_commit(view->swayc);
+
 	struct sway_seat *seat = input_manager_current_seat(input_manager);
 	if (seat->cursor) {
 		cursor_send_pointer_motion(seat->cursor, 0, false);

sway/commands/floating.c

@@ -36,5 +36,8 @@ struct cmd_results *cmd_floating(int argc, char **argv) {
 
 	container_set_floating(container, wants_floating);
 
+	struct sway_container *workspace = container_parent(container, C_WORKSPACE);
+	arrange_and_commit(workspace);
+
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }

sway/commands/fullscreen.c

@@ -1,6 +1,7 @@
 #include "log.h"
 #include "sway/commands.h"
 #include "sway/config.h"
+#include "sway/tree/arrange.h"
 #include "sway/tree/container.h"
 #include "sway/tree/view.h"
 #include "sway/tree/layout.h"
@@ -32,5 +33,8 @@ struct cmd_results *cmd_fullscreen(int argc, char **argv) {
 
 	view_set_fullscreen(view, wants_fullscreen);
 
+	struct sway_container *workspace = container_parent(container, C_WORKSPACE);
+	arrange_and_commit(workspace->parent);
+
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }

sway/commands/gaps.c

@@ -31,21 +31,19 @@ struct cmd_results *cmd_gaps(int argc, char **argv) {
 
 		if (strcmp(argv[1], "on") == 0) {
 			config->edge_gaps = true;
-			arrange_root();
 		} else if (strcmp(argv[1], "off") == 0) {
 			config->edge_gaps = false;
-			arrange_root();
 		} else if (strcmp(argv[1], "toggle") == 0) {
 			if (!config->active) {
 				return cmd_results_new(CMD_INVALID, "gaps",
 					"Cannot toggle gaps while not running.");
 			}
 			config->edge_gaps = !config->edge_gaps;
-			arrange_root();
 		} else {
 			return cmd_results_new(CMD_INVALID, "gaps",
 				"gaps edge_gaps on|off|toggle");
 		}
+		arrange_and_commit(&root_container);
 	} else {
 		int amount_idx = 0; // the current index in argv
 		enum gaps_op op = GAPS_OP_SET;
@@ -120,13 +118,13 @@ struct cmd_results *cmd_gaps(int argc, char **argv) {
 					"gaps inner|outer <amount>");
 			}
 			return cmd_results_new(CMD_INVALID, "gaps",
-				"gaps inner|outer all|workspace|current set|plus|minus <amount>"); 
+				"gaps inner|outer all|workspace|current set|plus|minus <amount>");
 		}
 
 		if (amount_idx == 0) { // gaps <amount>
 			config->gaps_inner = val;
 			config->gaps_outer = val;
-			arrange_root();
+			arrange_and_commit(&root_container);
 			return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 		}
 		// Other variants. The middle-length variant (gaps inner|outer <amount>)
@@ -150,14 +148,14 @@ struct cmd_results *cmd_gaps(int argc, char **argv) {
 				break;
 			}
 		}
- 
+
 		if (scope == GAPS_SCOPE_ALL) {
 			if (inner) {
 				config->gaps_inner = total;
 			} else {
 				config->gaps_outer = total;
 			}
-			arrange_root();
+			arrange_and_commit(&root_container);
 		} else {
 			struct sway_container *c =
 				config->handler_context.current_container;
@@ -171,11 +169,7 @@ struct cmd_results *cmd_gaps(int argc, char **argv) {
 				c->gaps_outer = total;
 			}
 
-			if (c->parent) {
+			arrange_and_commit(c->parent ? c->parent : &root_container);
-				arrange_children_of(c->parent);
-			} else {
-				arrange_root();
-			}
 		}
 	}
 

sway/commands/layout.c

@@ -49,7 +49,7 @@ struct cmd_results *cmd_layout(int argc, char **argv) {
 	}
 
 	container_notify_subtree_changed(parent);
-	arrange_children_of(parent);
+	arrange_and_commit(parent);
 
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }

sway/commands/move.c

@@ -5,8 +5,10 @@
 #include <wlr/types/wlr_output_layout.h>
 #include <wlr/util/log.h>
 #include "sway/commands.h"
+#include "sway/desktop/transaction.h"
 #include "sway/input/seat.h"
 #include "sway/output.h"
+#include "sway/tree/arrange.h"
 #include "sway/tree/container.h"
 #include "sway/tree/layout.h"
 #include "sway/tree/workspace.h"
@@ -88,6 +90,7 @@ static struct cmd_results *cmd_move_container(struct sway_container *current,
 		}
 		free(ws_name);
 		struct sway_container *old_parent = current->parent;
+		struct sway_container *old_ws = container_parent(current, C_WORKSPACE);
 		struct sway_container *destination = seat_get_focus_inactive(
 				config->handler_context.seat, ws);
 		container_move_to(current, destination);
@@ -96,6 +99,15 @@ static struct cmd_results *cmd_move_container(struct sway_container *current,
 		seat_set_focus(config->handler_context.seat, focus);
 		container_reap_empty(old_parent);
 		container_reap_empty(destination->parent);
+
+		// TODO: Ideally we would arrange the surviving parent after reaping,
+		// but container_reap_empty does not return it, so we arrange the
+		// workspace instead.
+		struct sway_transaction *txn = transaction_create();
+		arrange_windows(old_ws, txn);
+		arrange_windows(destination->parent, txn);
+		transaction_commit(txn);
+
 		return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 	} else if (strcasecmp(argv[1], "to") == 0
 			&& strcasecmp(argv[2], "output") == 0) {
@@ -121,10 +133,20 @@ static struct cmd_results *cmd_move_container(struct sway_container *current,
 			focus = destination->children->items[0];
 		}
 		struct sway_container *old_parent = current->parent;
+		struct sway_container *old_ws = container_parent(current, C_WORKSPACE);
 		container_move_to(current, focus);
 		seat_set_focus(config->handler_context.seat, old_parent);
 		container_reap_empty(old_parent);
 		container_reap_empty(focus->parent);
+
+		// TODO: Ideally we would arrange the surviving parent after reaping,
+		// but container_reap_empty does not return it, so we arrange the
+		// workspace instead.
+		struct sway_transaction *txn = transaction_create();
+		arrange_windows(old_ws, txn);
+		arrange_windows(focus->parent, txn);
+		transaction_commit(txn);
+
 		return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 	}
 	return cmd_results_new(CMD_INVALID, "move", expected_syntax);
@@ -152,6 +174,37 @@ static struct cmd_results *cmd_move_workspace(struct sway_container *current,
 		current = container_parent(current, C_WORKSPACE);
 	}
 	container_move_to(current, destination);
+
+	struct sway_transaction *txn = transaction_create();
+	arrange_windows(source, txn);
+	arrange_windows(destination, txn);
+	transaction_commit(txn);
+
+	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
+}
+
+static struct cmd_results *move_in_direction(struct sway_container *container,
+		enum movement_direction direction, int move_amt) {
+	if (container->type == C_WORKSPACE) {
+		return cmd_results_new(CMD_FAILURE, "move",
+				"Cannot move workspaces in a direction");
+	}
+	// For simplicity, we'll arrange the entire workspace. The reason for this
+	// is moving the container might reap the old parent, and container_move
+	// does not return a surviving parent.
+	// TODO: Make container_move return the surviving parent so we can arrange
+	// just that.
+	struct sway_container *old_ws = container_parent(container, C_WORKSPACE);
+	container_move(container, direction, move_amt);
+	struct sway_container *new_ws = container_parent(container, C_WORKSPACE);
+
+	struct sway_transaction *txn = transaction_create();
+	arrange_windows(old_ws, txn);
+	if (new_ws != old_ws) {
+		arrange_windows(new_ws, txn);
+	}
+	transaction_commit(txn);
+
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }
 
@@ -173,13 +226,13 @@ struct cmd_results *cmd_move(int argc, char **argv) {
 	}
 
 	if (strcasecmp(argv[0], "left") == 0) {
-		container_move(current, MOVE_LEFT, move_amt);
+		return move_in_direction(current, MOVE_LEFT, move_amt);
 	} else if (strcasecmp(argv[0], "right") == 0) {
-		container_move(current, MOVE_RIGHT, move_amt);
+		return move_in_direction(current, MOVE_RIGHT, move_amt);
 	} else if (strcasecmp(argv[0], "up") == 0) {
-		container_move(current, MOVE_UP, move_amt);
+		return move_in_direction(current, MOVE_UP, move_amt);
 	} else if (strcasecmp(argv[0], "down") == 0) {
-		container_move(current, MOVE_DOWN, move_amt);
+		return move_in_direction(current, MOVE_DOWN, move_amt);
 	} else if (strcasecmp(argv[0], "container") == 0
 			|| strcasecmp(argv[0], "window") == 0) {
 		return cmd_move_container(current, argc, argv);

sway/commands/reload.c

@@ -12,6 +12,6 @@ struct cmd_results *cmd_reload(int argc, char **argv) {
 	}
 
 	load_swaybars();
-	arrange_root();
+	arrange_and_commit(&root_container);
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }

sway/commands/resize.c

@@ -182,7 +182,7 @@ static void resize_tiled(int amount, enum resize_axis axis) {
 		}
 	}
 
-	arrange_children_of(parent->parent);
+	arrange_and_commit(parent->parent);
 }
 
 static void resize(int amount, enum resize_axis axis, enum resize_unit unit) {

sway/commands/smart_gaps.c

@@ -16,13 +16,14 @@ struct cmd_results *cmd_smart_gaps(int argc, char **argv) {
 
 	if (strcmp(argv[0], "on") == 0) {
 		config->smart_gaps = true;
-		arrange_root();
 	} else if (strcmp(argv[0], "off") == 0) {
 		config->smart_gaps = false;
-		arrange_root();
 	} else {
 		return cmd_results_new(CMD_INVALID, "smart_gaps",
 			"Expected 'smart_gaps <on|off>' ");
 	}
+
+	arrange_and_commit(&root_container);
+
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }

sway/commands/split.c

@@ -16,7 +16,7 @@ static struct cmd_results *do_split(int layout) {
 	}
 	struct sway_container *parent = container_split(con, layout);
 	container_create_notify(parent);
-	arrange_children_of(parent);
+	arrange_and_commit(parent->parent);
 
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }

sway/commands/swap.c

@@ -1,6 +1,8 @@
 #include <strings.h>
 #include <wlr/util/log.h>
 #include "sway/commands.h"
+#include "sway/desktop/transaction.h"
+#include "sway/tree/arrange.h"
 #include "sway/tree/layout.h"
 #include "sway/tree/view.h"
 #include "stringop.h"
@@ -76,5 +78,15 @@ struct cmd_results *cmd_swap(int argc, char **argv) {
 	}
 
 	container_swap(current, other);
+
+	struct sway_transaction *txn = transaction_create();
+	arrange_windows(current->parent, txn);
+
+	if (other->parent != current->parent) {
+		arrange_windows(other->parent, txn);
+	}
+
+	transaction_commit(txn);
+
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }

sway/config.c

@@ -531,7 +531,7 @@ static int detect_brace_on_following_line(FILE *file, char *line,
 		} while (peeked && strlen(peeked) == 0);
 
 		if (peeked && strlen(peeked) == 1 && peeked[0] == '{') {
-			fseek(file, position, SEEK_SET); 
+			fseek(file, position, SEEK_SET);
 		} else {
 			lines = 0;
 		}
@@ -735,6 +735,6 @@ void config_update_font_height(bool recalculate) {
 	}
 
 	if (config->font_height != prev_max_height) {
-		arrange_root();
+		arrange_and_commit(&root_container);
 	}
 }

sway/desktop/desktop.c

@@ -7,7 +7,8 @@ void desktop_damage_surface(struct wlr_surface *surface, double lx, double ly,
 	for (int i = 0; i < root_container.children->length; ++i) {
 		struct sway_container *cont = root_container.children->items[i];
 		if (cont->type == C_OUTPUT) {
-			output_damage_surface(cont->sway_output, lx - cont->x, ly - cont->y,
+			output_damage_surface(cont->sway_output,
+				lx - cont->current.swayc_x, ly - cont->current.swayc_y,
 				surface, whole);
 		}
 	}

sway/desktop/layer_shell.c

@@ -176,7 +176,7 @@ void arrange_layers(struct sway_output *output) {
 				sizeof(struct wlr_box)) != 0) {
 		wlr_log(L_DEBUG, "Usable area changed, rearranging output");
 		memcpy(&output->usable_area, &usable_area, sizeof(struct wlr_box));
-		arrange_output(output->swayc);
+		arrange_and_commit(output->swayc);
 	}
 
 	// Arrange non-exlusive surfaces from top->bottom

sway/desktop/output.c

@@ -6,6 +6,7 @@
 #include <wayland-server.h>
 #include <wlr/render/wlr_renderer.h>
 #include <wlr/types/wlr_box.h>
+#include <wlr/types/wlr_buffer.h>
 #include <wlr/types/wlr_matrix.h>
 #include <wlr/types/wlr_output_damage.h>
 #include <wlr/types/wlr_output_layout.h>
@@ -69,6 +70,7 @@ struct render_data {
 	struct root_geometry root_geo;
 	struct sway_output *output;
 	pixman_region32_t *damage;
+	struct sway_view *view;
 	float alpha;
 };
 
@@ -100,8 +102,8 @@ static bool get_surface_box(struct root_geometry *geo,
 	wlr_box_rotated_bounds(&box, geo->rotation, &rotated_box);
 
 	struct wlr_box output_box = {
-		.width = output->swayc->width,
+		.width = output->swayc->current.swayc_width,
-		.height = output->swayc->height,
+		.height = output->swayc->current.swayc_height,
 	};
 
 	struct wlr_box intersection;
@@ -124,10 +126,10 @@ static void output_view_for_each_surface(struct sway_view *view,
 		struct root_geometry *geo, wlr_surface_iterator_func_t iterator,
 		void *user_data) {
 	struct render_data *data = user_data;
-	geo->x = view->x - data->output->swayc->x;
+	geo->x = view->swayc->current.view_x - data->output->swayc->current.swayc_x;
-	geo->y = view->y - data->output->swayc->y;
+	geo->y = view->swayc->current.view_y - data->output->swayc->current.swayc_y;
-	geo->width = view->surface->current->width;
+	geo->width = view->swayc->current.view_width;
-	geo->height = view->surface->current->height;
+	geo->height = view->swayc->current.view_height;
 	geo->rotation = 0; // TODO
 
 	view_for_each_surface(view, iterator, user_data);
@@ -153,8 +155,8 @@ static void unmanaged_for_each_surface(struct wl_list *unmanaged,
 	wl_list_for_each(unmanaged_surface, unmanaged, link) {
 		struct wlr_xwayland_surface *xsurface =
 			unmanaged_surface->wlr_xwayland_surface;
-		double ox = unmanaged_surface->lx - output->swayc->x;
+		double ox = unmanaged_surface->lx - output->swayc->current.swayc_x;
-		double oy = unmanaged_surface->ly - output->swayc->y;
+		double oy = unmanaged_surface->ly - output->swayc->current.swayc_y;
 
 		surface_for_each_surface(xsurface->surface, ox, oy, geo,
 			iterator, user_data);
@@ -241,13 +243,13 @@ static void render_surface_iterator(struct wlr_surface *surface, int sx, int sy,
 	float alpha = data->alpha;
 
 	struct wlr_texture *texture = wlr_surface_get_texture(surface);
-	if (texture == NULL) {
+	if (!texture) {
 		return;
 	}
 
 	struct wlr_box box;
 	bool intersects = get_surface_box(&data->root_geo, data->output, surface,
-		sx, sy, &box);
+			sx, sy, &box);
 	if (!intersects) {
 		return;
 	}
@@ -341,64 +343,107 @@ static void render_view_surfaces(struct sway_view *view,
 	struct render_data data = {
 		.output = output,
 		.damage = damage,
+		.view = view,
 		.alpha = alpha,
 	};
 	output_view_for_each_surface(
 			view, &data.root_geo, render_surface_iterator, &data);
 }
 
+static void render_saved_view(struct sway_view *view,
+		struct sway_output *output, pixman_region32_t *damage, float alpha) {
+	struct wlr_output *wlr_output = output->wlr_output;
+
+	int width, height;
+	struct wlr_texture *texture =
+		transaction_get_saved_texture(view, &width, &height);
+	if (!texture) {
+		return;
+	}
+	struct wlr_box box = {
+		.x = view->swayc->current.view_x - output->swayc->current.swayc_x,
+		.y = view->swayc->current.view_y - output->swayc->current.swayc_y,
+		.width = width,
+		.height = height,
+	};
+
+	struct wlr_box output_box = {
+		.width = output->swayc->current.swayc_width,
+		.height = output->swayc->current.swayc_height,
+	};
+
+	struct wlr_box intersection;
+	bool intersects = wlr_box_intersection(&output_box, &box, &intersection);
+	if (!intersects) {
+		return;
+	}
+
+	scale_box(&box, wlr_output->scale);
+
+	float matrix[9];
+	wlr_matrix_project_box(matrix, &box, WL_OUTPUT_TRANSFORM_NORMAL, 0,
+		wlr_output->transform_matrix);
+
+	render_texture(wlr_output, damage, texture, &box, matrix, alpha);
+}
+
 /**
  * Render a view's surface and left/bottom/right borders.
  */
 static void render_view(struct sway_output *output, pixman_region32_t *damage,
 		struct sway_container *con, struct border_colors *colors) {
 	struct sway_view *view = con->sway_view;
-	render_view_surfaces(view, output, damage, view->swayc->alpha);
+	if (view->swayc->instructions->length) {
+		render_saved_view(view, output, damage, view->swayc->alpha);
+	} else {
+		render_view_surfaces(view, output, damage, view->swayc->alpha);
+	}
 
 	struct wlr_box box;
 	float output_scale = output->wlr_output->scale;
 	float color[4];
+	struct sway_container_state *state = &con->current;
 
-	if (view->border != B_NONE) {
+	if (state->border != B_NONE) {
-		if (view->border_left) {
+		if (state->border_left) {
 			memcpy(&color, colors->child_border, sizeof(float) * 4);
 			premultiply_alpha(color, con->alpha);
-			box.x = con->x;
+			box.x = state->swayc_x;
-			box.y = view->y;
+			box.y = state->view_y;
-			box.width = view->border_thickness;
+			box.width = state->border_thickness;
-			box.height = view->height;
+			box.height = state->view_height;
 			scale_box(&box, output_scale);
 			render_rect(output->wlr_output, damage, &box, color);
 		}
 
-		if (view->border_right) {
+		if (state->border_right) {
-			if (con->parent->children->length == 1
+			if (state->parent->current.children->length == 1
-					&& con->parent->layout == L_HORIZ) {
+					&& state->parent->current.layout == L_HORIZ) {
 				memcpy(&color, colors->indicator, sizeof(float) * 4);
 			} else {
 				memcpy(&color, colors->child_border, sizeof(float) * 4);
 			}
 			premultiply_alpha(color, con->alpha);
-			box.x = view->x + view->width;
+			box.x = state->view_x + state->view_width;
-			box.y = view->y;
+			box.y = state->view_y;
-			box.width = view->border_thickness;
+			box.width = state->border_thickness;
-			box.height = view->height;
+			box.height = state->view_height;
 			scale_box(&box, output_scale);
 			render_rect(output->wlr_output, damage, &box, color);
 		}
 
-		if (view->border_bottom) {
+		if (state->border_bottom) {
-			if (con->parent->children->length == 1
+			if (state->parent->current.children->length == 1
-					&& con->parent->layout == L_VERT) {
+					&& con->current.parent->current.layout == L_VERT) {
 				memcpy(&color, colors->indicator, sizeof(float) * 4);
 			} else {
 				memcpy(&color, colors->child_border, sizeof(float) * 4);
 			}
 			premultiply_alpha(color, con->alpha);
-			box.x = con->x;
+			box.x = state->swayc_x;
-			box.y = view->y + view->height;
+			box.y = state->view_y + state->view_height;
-			box.width = con->width;
+			box.width = state->swayc_width;
-			box.height = view->border_thickness;
+			box.height = state->border_thickness;
 			scale_box(&box, output_scale);
 			render_rect(output->wlr_output, damage, &box, color);
 		}
@@ -422,11 +467,13 @@ static void render_titlebar(struct sway_output *output,
 		struct wlr_texture *marks_texture) {
 	struct wlr_box box;
 	float color[4];
-	struct sway_view *view = con->type == C_VIEW ? con->sway_view : NULL;
+	struct sway_container_state *state = &con->current;
 	float output_scale = output->wlr_output->scale;
-	enum sway_container_layout layout = con->parent->layout;
+	enum sway_container_layout layout = state->parent->current.layout;
-	bool is_last_child =
+	list_t *children = state->parent->current.children;
-		con->parent->children->items[con->parent->children->length - 1] == con;
+	bool is_last_child = children->items[children->length - 1] == con;
+	double output_x = output->swayc->current.swayc_x;
+	double output_y = output->swayc->current.swayc_y;
 
 	// Single pixel bar above title
 	memcpy(&color, colors->border, sizeof(float) * 4);
@@ -443,9 +490,9 @@ static void render_titlebar(struct sway_output *output,
 	bool connects_sides = false;
 	if (layout == L_HORIZ || layout == L_VERT ||
 			(layout == L_STACKED && is_last_child)) {
-		if (view) {
+		if (con->type == C_VIEW) {
-			left_offset = view->border_left * view->border_thickness;
+			left_offset = state->border_left * state->border_thickness;
-			right_offset = view->border_right * view->border_thickness;
+			right_offset = state->border_right * state->border_thickness;
 			connects_sides = true;
 		}
 	}
@@ -479,10 +526,9 @@ static void render_titlebar(struct sway_output *output,
 		struct wlr_box texture_box;
 		wlr_texture_get_size(marks_texture,
 			&texture_box.width, &texture_box.height);
-		texture_box.x = (x - output->swayc->x + width - TITLEBAR_H_PADDING)
+		texture_box.x = (x - output_x + width - TITLEBAR_H_PADDING)
 			* output_scale - texture_box.width;
-		texture_box.y = (y - output->swayc->y + TITLEBAR_V_PADDING)
+		texture_box.y = (y - output_y + TITLEBAR_V_PADDING) * output_scale;
-			* output_scale;
 
 		float matrix[9];
 		wlr_matrix_project_box(matrix, &texture_box,
@@ -503,10 +549,8 @@ static void render_titlebar(struct sway_output *output,
 		struct wlr_box texture_box;
 		wlr_texture_get_size(title_texture,
 			&texture_box.width, &texture_box.height);
-		texture_box.x = (x - output->swayc->x + TITLEBAR_H_PADDING)
+		texture_box.x = (x - output_x + TITLEBAR_H_PADDING) * output_scale;
-			* output_scale;
+		texture_box.y = (y - output_y + TITLEBAR_V_PADDING) * output_scale;
-		texture_box.y = (y - output->swayc->y + TITLEBAR_V_PADDING)
-			* output_scale;
 
 		float matrix[9];
 		wlr_matrix_project_box(matrix, &texture_box,
@@ -566,15 +610,15 @@ static void render_titlebar(struct sway_output *output,
 		// Left pixel in line with bottom bar
 		box.x = x;
 		box.y = y + container_titlebar_height() - TITLEBAR_BORDER_THICKNESS;
-		box.width = view->border_thickness * view->border_left;
+		box.width = state->border_thickness * state->border_left;
 		box.height = TITLEBAR_BORDER_THICKNESS;
 		scale_box(&box, output_scale);
 		render_rect(output->wlr_output, output_damage, &box, color);
 
 		// Right pixel in line with bottom bar
-		box.x = x + width - view->border_thickness * view->border_right;
+		box.x = x + width - state->border_thickness * state->border_right;
 		box.y = y + container_titlebar_height() - TITLEBAR_BORDER_THICKNESS;
-		box.width = view->border_thickness * view->border_right;
+		box.width = state->border_thickness * state->border_right;
 		box.height = TITLEBAR_BORDER_THICKNESS;
 		scale_box(&box, output_scale);
 		render_rect(output->wlr_output, output_damage, &box, color);
@@ -587,8 +631,8 @@ static void render_titlebar(struct sway_output *output,
 static void render_top_border(struct sway_output *output,
 		pixman_region32_t *output_damage, struct sway_container *con,
 		struct border_colors *colors) {
-	struct sway_view *view = con->sway_view;
+	struct sway_container_state *state = &con->current;
-	if (!view->border_top) {
+	if (!state->border_top) {
 		return;
 	}
 	struct wlr_box box;
@@ -598,10 +642,10 @@ static void render_top_border(struct sway_output *output,
 	// Child border - top edge
 	memcpy(&color, colors->child_border, sizeof(float) * 4);
 	premultiply_alpha(color, con->alpha);
-	box.x = con->x;
+	box.x = state->swayc_x;
-	box.y = con->y;
+	box.y = state->swayc_y;
-	box.width = con->width;
+	box.width = state->swayc_width;
-	box.height = view->border_thickness;
+	box.height = state->border_thickness;
 	scale_box(&box, output_scale);
 	render_rect(output->wlr_output, output_damage, &box, color);
 }
@@ -621,30 +665,34 @@ static void render_container_simple(struct sway_output *output,
 	struct sway_seat *seat = input_manager_current_seat(input_manager);
 	struct sway_container *focus = seat_get_focus(seat);
 
-	for (int i = 0; i < con->children->length; ++i) {
+	for (int i = 0; i < con->current.children->length; ++i) {
-		struct sway_container *child = con->children->items[i];
+		struct sway_container *child = con->current.children->items[i];
 
 		if (child->type == C_VIEW) {
+			struct sway_view *view = child->sway_view;
 			struct border_colors *colors;
 			struct wlr_texture *title_texture;
 			struct wlr_texture *marks_texture;
+			struct sway_container_state *state = &child->current;
+
 			if (focus == child || parent_focused) {
 				colors = &config->border_colors.focused;
 				title_texture = child->title_focused;
-				marks_texture = child->sway_view->marks_focused;
+				marks_texture = view->marks_focused;
 			} else if (seat_get_focus_inactive(seat, con) == child) {
 				colors = &config->border_colors.focused_inactive;
 				title_texture = child->title_focused_inactive;
-				marks_texture = child->sway_view->marks_focused_inactive;
+				marks_texture = view->marks_focused_inactive;
 			} else {
 				colors = &config->border_colors.unfocused;
 				title_texture = child->title_unfocused;
-				marks_texture = child->sway_view->marks_unfocused;
+				marks_texture = view->marks_unfocused;
 			}
 
-			if (child->sway_view->border == B_NORMAL) {
+			if (state->border == B_NORMAL) {
-				render_titlebar(output, damage, child, child->x, child->y,
+				render_titlebar(output, damage, child, state->swayc_x,
-						child->width, colors, title_texture, marks_texture);
+						state->swayc_y, state->swayc_width, colors,
+						title_texture, marks_texture);
 			} else {
 				render_top_border(output, damage, child, colors);
 			}
@@ -662,83 +710,23 @@ static void render_container_simple(struct sway_output *output,
 static void render_container_tabbed(struct sway_output *output,
 		pixman_region32_t *damage, struct sway_container *con,
 		bool parent_focused) {
-	if (!con->children->length) {
+	if (!con->current.children->length) {
 		return;
 	}
 	struct sway_seat *seat = input_manager_current_seat(input_manager);
 	struct sway_container *focus = seat_get_focus(seat);
-	struct sway_container *current = seat_get_active_child(seat, con);
+	struct sway_container *current = seat_get_active_current_child(seat, con);
-	struct border_colors *current_colors = NULL;
+	struct border_colors *current_colors = &config->border_colors.unfocused;
+	struct sway_container_state *pstate = &con->current;
 
 	// Render tabs
-	for (int i = 0; i < con->children->length; ++i) {
+	for (int i = 0; i < con->current.children->length; ++i) {
-		struct sway_container *child = con->children->items[i];
+		struct sway_container *child = con->current.children->items[i];
+		struct sway_view *view = child->type == C_VIEW ? child->sway_view : NULL;
+		struct sway_container_state *cstate = &child->current;
 		struct border_colors *colors;
 		struct wlr_texture *title_texture;
 		struct wlr_texture *marks_texture;
-		struct sway_view *view =
-			child->type == C_VIEW ? child->sway_view : NULL;
-
-		if (focus == child || parent_focused) {
-			colors = &config->border_colors.focused;
-			title_texture = child->title_focused;
-			marks_texture = view ? view->marks_focused : NULL;
-		} else if (child == current) {
-			colors = &config->border_colors.focused_inactive;
-			title_texture = child->title_focused_inactive;
-			marks_texture = view ? view->marks_focused : NULL;
-		} else {
-			colors = &config->border_colors.unfocused;
-			title_texture = child->title_unfocused;
-			marks_texture = view ? view->marks_unfocused : NULL;
-		}
-
-		int tab_width = con->width / con->children->length;
-		int x = con->x + tab_width * i;
-		// Make last tab use the remaining width of the parent
-		if (i == con->children->length - 1) {
-			tab_width = con->width - tab_width * i;
-		}
-
-		render_titlebar(output, damage, child, x, child->y, tab_width, colors,
-				title_texture, marks_texture);
-
-		if (child == current) {
-			current_colors = colors;
-		}
-	}
-
-	// Render surface and left/right/bottom borders
-	if (current->type == C_VIEW) {
-		render_view(output, damage, current, current_colors);
-	} else {
-		render_container(output, damage, current,
-				parent_focused || current == focus);
-	}
-}
-
-/**
- * Render a container's children using the L_STACKED layout.
- */
-static void render_container_stacked(struct sway_output *output,
-		pixman_region32_t *damage, struct sway_container *con,
-		bool parent_focused) {
-	if (!con->children->length) {
-		return;
-	}
-	struct sway_seat *seat = input_manager_current_seat(input_manager);
-	struct sway_container *focus = seat_get_focus(seat);
-	struct sway_container *current = seat_get_active_child(seat, con);
-	struct border_colors *current_colors = NULL;
-
-	// Render titles
-	for (int i = 0; i < con->children->length; ++i) {
-		struct sway_container *child = con->children->items[i];
-		struct border_colors *colors;
-		struct wlr_texture *title_texture;
-		struct wlr_texture *marks_texture;
-		struct sway_view *view =
-			child->type == C_VIEW ? child->sway_view : NULL;
 
 		if (focus == child || parent_focused) {
 			colors = &config->border_colors.focused;
@@ -754,8 +742,14 @@ static void render_container_stacked(struct sway_output *output,
 			marks_texture = view ? view->marks_unfocused : NULL;
 		}
 
-		int y = con->y + container_titlebar_height() * i;
+		int tab_width = pstate->swayc_width / pstate->children->length;
-		render_titlebar(output, damage, child, child->x, y, child->width,
+		int x = pstate->swayc_x + tab_width * i;
+		// Make last tab use the remaining width of the parent
+		if (i == pstate->children->length - 1) {
+			tab_width = pstate->swayc_width - tab_width * i;
+		}
+
+		render_titlebar(output, damage, child, x, cstate->swayc_y, tab_width,
 				colors, title_texture, marks_texture);
 
 		if (child == current) {
@@ -764,18 +758,78 @@ static void render_container_stacked(struct sway_output *output,
 	}
 
 	// Render surface and left/right/bottom borders
-	if (current->type == C_VIEW) {
+	if (current) {
-		render_view(output, damage, current, current_colors);
+		if (current->type == C_VIEW) {
-	} else {
+			render_view(output, damage, current, current_colors);
-		render_container(output, damage, current,
+		} else {
-				parent_focused || current == focus);
+			render_container(output, damage, current,
+					parent_focused || current == focus);
+		}
+	}
+}
+
+/**
+ * Render a container's children using the L_STACKED layout.
+ */
+static void render_container_stacked(struct sway_output *output,
+		pixman_region32_t *damage, struct sway_container *con,
+		bool parent_focused) {
+	if (!con->current.children->length) {
+		return;
+	}
+	struct sway_seat *seat = input_manager_current_seat(input_manager);
+	struct sway_container *focus = seat_get_focus(seat);
+	struct sway_container *current = seat_get_active_current_child(seat, con);
+	struct border_colors *current_colors = &config->border_colors.unfocused;
+	struct sway_container_state *pstate = &con->current;
+
+	// Render titles
+	for (int i = 0; i < con->current.children->length; ++i) {
+		struct sway_container *child = con->current.children->items[i];
+		struct sway_view *view = child->type == C_VIEW ? child->sway_view : NULL;
+		struct sway_container_state *cstate = &child->current;
+		struct border_colors *colors;
+		struct wlr_texture *title_texture;
+		struct wlr_texture *marks_texture;
+
+		if (focus == child || parent_focused) {
+			colors = &config->border_colors.focused;
+			title_texture = child->title_focused;
+			marks_texture = view ? view->marks_focused : NULL;
+		} else if (child == current) {
+			colors = &config->border_colors.focused_inactive;
+			title_texture = child->title_focused_inactive;
+			marks_texture = view ? view->marks_focused_inactive : NULL;
+		} else {
+			colors = &config->border_colors.unfocused;
+			title_texture = child->title_unfocused;
+			marks_texture = view ? view->marks_unfocused : NULL;
+		}
+
+		int y = pstate->swayc_y + container_titlebar_height() * i;
+		render_titlebar(output, damage, child, cstate->swayc_x, y,
+				cstate->swayc_width, colors, title_texture, marks_texture);
+
+		if (child == current) {
+			current_colors = colors;
+		}
+	}
+
+	// Render surface and left/right/bottom borders
+	if (current) {
+		if (current->type == C_VIEW) {
+			render_view(output, damage, current, current_colors);
+		} else {
+			render_container(output, damage, current,
+					parent_focused || current == focus);
+		}
 	}
 }
 
 static void render_container(struct sway_output *output,
 		pixman_region32_t *damage, struct sway_container *con,
 		bool parent_focused) {
-	switch (con->layout) {
+	switch (con->current.layout) {
 	case L_NONE:
 	case L_HORIZ:
 	case L_VERT:
@@ -812,10 +866,11 @@ static void render_floating_container(struct sway_output *soutput,
 			marks_texture = view->marks_unfocused;
 		}
 
-		if (con->sway_view->border == B_NORMAL) {
+		if (con->current.border == B_NORMAL) {
-			render_titlebar(soutput, damage, con, con->x, con->y, con->width,
+			render_titlebar(soutput, damage, con, con->current.swayc_x,
-					colors, title_texture, marks_texture);
+					con->current.swayc_y, con->current.swayc_width, colors,
-		} else if (con->sway_view->border != B_NONE) {
+					title_texture, marks_texture);
+		} else if (con->current.border != B_NONE) {
 			render_top_border(soutput, damage, con, colors);
 		}
 		render_view(soutput, damage, con, colors);
@@ -826,17 +881,18 @@ static void render_floating_container(struct sway_output *soutput,
 
 static void render_floating(struct sway_output *soutput,
 		pixman_region32_t *damage) {
-	for (int i = 0; i < root_container.children->length; ++i) {
+	for (int i = 0; i < root_container.current.children->length; ++i) {
-		struct sway_container *output = root_container.children->items[i];
+		struct sway_container *output =
-		for (int j = 0; j < output->children->length; ++j) {
+			root_container.current.children->items[i];
-			struct sway_container *workspace = output->children->items[j];
+		for (int j = 0; j < output->current.children->length; ++j) {
-			struct sway_workspace *ws = workspace->sway_workspace;
+			struct sway_container *ws = output->current.children->items[j];
-			if (!workspace_is_visible(workspace)) {
+			if (!workspace_is_visible(ws)) {
 				continue;
 			}
-			for (int k = 0; k < ws->floating->children->length; ++k) {
+			list_t *floating =
-				struct sway_container *floater =
+				ws->current.ws_floating->current.children;
-					ws->floating->children->items[k];
+			for (int k = 0; k < floating->length; ++k) {
+				struct sway_container *floater = floating->items[k];
 				render_floating_container(soutput, damage, floater);
 			}
 		}
@@ -850,7 +906,7 @@ static struct sway_container *output_get_active_workspace(
 		seat_get_focus_inactive(seat, output->swayc);
 	if (!focus) {
 		// We've never been to this output before
-		focus = output->swayc->children->items[0];
+		focus = output->swayc->current.children->items[0];
 	}
 	struct sway_container *workspace = focus;
 	if (workspace->type != C_WORKSPACE) {
@@ -891,8 +947,9 @@ static void render_output(struct sway_output *output, struct timespec *when,
 	}
 
 	struct sway_container *workspace = output_get_active_workspace(output);
+	struct sway_view *fullscreen_view = workspace->current.ws_fullscreen;
 
-	if (workspace->sway_workspace->fullscreen) {
+	if (fullscreen_view) {
 		float clear_color[] = {0.0f, 0.0f, 0.0f, 1.0f};
 
 		int nrects;
@@ -903,10 +960,9 @@ static void render_output(struct sway_output *output, struct timespec *when,
 		}
 
 		// TODO: handle views smaller than the output
-		render_view_surfaces(
+		render_view_surfaces(fullscreen_view, output, damage, 1.0f);
-				workspace->sway_workspace->fullscreen, output, damage, 1.0f);
 
-		if (workspace->sway_workspace->fullscreen->type == SWAY_VIEW_XWAYLAND) {
+		if (fullscreen_view->type == SWAY_VIEW_XWAYLAND) {
 			render_unmanaged(output, damage,
 				&root_container.sway_root->xwayland_unmanaged);
 		}
@@ -1022,11 +1078,11 @@ static void send_frame_done(struct sway_output *output, struct timespec *when) {
 	};
 
 	struct sway_container *workspace = output_get_active_workspace(output);
-	if (workspace->sway_workspace->fullscreen) {
+	if (workspace->current.ws_fullscreen) {
 		send_frame_done_container_iterator(
-			workspace->sway_workspace->fullscreen->swayc, &data);
+			workspace->current.ws_fullscreen->swayc, &data);
 
-		if (workspace->sway_workspace->fullscreen->type == SWAY_VIEW_XWAYLAND) {
+		if (workspace->current.ws_fullscreen->type == SWAY_VIEW_XWAYLAND) {
 			send_frame_done_unmanaged(&data,
 				&root_container.sway_root->xwayland_unmanaged);
 		}
@@ -1168,6 +1224,16 @@ void output_damage_from_view(struct sway_output *output,
 	output_damage_view(output, view, false);
 }
 
+// Expecting an unscaled box in layout coordinates
+void output_damage_box(struct sway_output *output, struct wlr_box *_box) {
+	struct wlr_box box;
+	memcpy(&box, _box, sizeof(struct wlr_box));
+	box.x -= output->swayc->current.swayc_x;
+	box.y -= output->swayc->current.swayc_y;
+	scale_box(&box, output->wlr_output->scale);
+	wlr_output_damage_add_box(output->damage, &box);
+}
+
 static void output_damage_whole_container_iterator(struct sway_container *con,
 		void *data) {
 	struct sway_output *output = data;
@@ -1182,10 +1248,10 @@ static void output_damage_whole_container_iterator(struct sway_container *con,
 void output_damage_whole_container(struct sway_output *output,
 		struct sway_container *con) {
 	struct wlr_box box = {
-		.x = con->x - output->wlr_output->lx,
+		.x = con->current.swayc_x - output->wlr_output->lx,
-		.y = con->y - output->wlr_output->ly,
+		.y = con->current.swayc_y - output->wlr_output->ly,
-		.width = con->width,
+		.width = con->current.swayc_width,
-		.height = con->height,
+		.height = con->current.swayc_height,
 	};
 	scale_box(&box, output->wlr_output->scale);
 	wlr_output_damage_add_box(output->damage, &box);
@@ -1209,18 +1275,20 @@ static void handle_destroy(struct wl_listener *listener, void *data) {
 	wl_list_remove(&output->destroy.link);
 	output->wlr_output->data = NULL;
 	free(output);
+
+	arrange_and_commit(&root_container);
 }
 
 static void handle_mode(struct wl_listener *listener, void *data) {
 	struct sway_output *output = wl_container_of(listener, output, mode);
 	arrange_layers(output);
-	arrange_output(output->swayc);
+	arrange_and_commit(output->swayc);
 }
 
 static void handle_transform(struct wl_listener *listener, void *data) {
 	struct sway_output *output = wl_container_of(listener, output, transform);
 	arrange_layers(output);
-	arrange_output(output->swayc);
+	arrange_and_commit(output->swayc);
 }
 
 static void handle_scale_iterator(struct sway_container *view, void *data) {
@@ -1230,8 +1298,8 @@ static void handle_scale_iterator(struct sway_container *view, void *data) {
 static void handle_scale(struct wl_listener *listener, void *data) {
 	struct sway_output *output = wl_container_of(listener, output, scale);
 	arrange_layers(output);
-	arrange_output(output->swayc);
 	container_descendants(output->swayc, C_VIEW, handle_scale_iterator, NULL);
+	arrange_and_commit(output->swayc);
 }
 
 void handle_new_output(struct wl_listener *listener, void *data) {
@@ -1296,5 +1364,5 @@ void output_enable(struct sway_output *output) {
 	output->damage_destroy.notify = damage_handle_destroy;
 
 	arrange_layers(output);
-	arrange_root();
+	arrange_and_commit(&root_container);
 }

sway/desktop/transaction.c

@@ -0,0 +1,415 @@
+#define _POSIX_C_SOURCE 200809L
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <wlr/types/wlr_buffer.h>
+#include <wlr/types/wlr_linux_dmabuf.h>
+#include "sway/debug.h"
+#include "sway/desktop/transaction.h"
+#include "sway/output.h"
+#include "sway/tree/container.h"
+#include "sway/tree/view.h"
+#include "sway/tree/workspace.h"
+#include "list.h"
+#include "log.h"
+
+/**
+ * How long we should wait for views to respond to the configure before giving
+ * up and applying the transaction anyway.
+ */
+#define TIMEOUT_MS 200
+
+/**
+ * If enabled, sway will always wait for the transaction timeout before
+ * applying it, rather than applying it when the views are ready. This allows us
+ * to observe the rendered state while a transaction is in progress.
+ */
+#define TRANSACTION_DEBUG false
+
+struct sway_transaction {
+	struct wl_event_source *timer;
+	list_t *instructions;   // struct sway_transaction_instruction *
+	size_t num_waiting;
+	size_t num_configures;
+	struct timespec create_time;
+	struct timespec commit_time;
+};
+
+struct sway_transaction_instruction {
+	struct sway_transaction *transaction;
+	struct sway_container *container;
+	struct sway_container_state state;
+	struct wlr_buffer *saved_buffer;
+	int saved_buffer_width, saved_buffer_height;
+	uint32_t serial;
+	bool ready;
+};
+
+struct sway_transaction *transaction_create() {
+	struct sway_transaction *transaction =
+		calloc(1, sizeof(struct sway_transaction));
+	transaction->instructions = create_list();
+	if (server.debug_txn_timings) {
+		clock_gettime(CLOCK_MONOTONIC, &transaction->create_time);
+	}
+	return transaction;
+}
+
+static void remove_saved_view_buffer(
+		struct sway_transaction_instruction *instruction) {
+	if (instruction->saved_buffer) {
+		wlr_buffer_unref(instruction->saved_buffer);
+		instruction->saved_buffer = NULL;
+	}
+}
+
+static void save_view_buffer(struct sway_view *view,
+		struct sway_transaction_instruction *instruction) {
+	if (!sway_assert(instruction->saved_buffer == NULL,
+				"Didn't expect instruction to have a saved buffer already")) {
+		remove_saved_view_buffer(instruction);
+	}
+	if (view->surface && wlr_surface_has_buffer(view->surface)) {
+		instruction->saved_buffer = wlr_buffer_ref(view->surface->buffer);
+		instruction->saved_buffer_width = view->surface->current->width;
+		instruction->saved_buffer_height = view->surface->current->height;
+	}
+}
+
+static void transaction_destroy(struct sway_transaction *transaction) {
+	// Free instructions
+	for (int i = 0; i < transaction->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			transaction->instructions->items[i];
+		struct sway_container *con = instruction->container;
+		for (int j = 0; j < con->instructions->length; ++j) {
+			if (con->instructions->items[j] == instruction) {
+				list_del(con->instructions, j);
+				break;
+			}
+		}
+		if (con->destroying && !con->instructions->length) {
+			container_free(con);
+		}
+		remove_saved_view_buffer(instruction);
+		free(instruction);
+	}
+	list_free(transaction->instructions);
+
+	if (transaction->timer) {
+		wl_event_source_remove(transaction->timer);
+	}
+	free(transaction);
+}
+
+static void copy_pending_state(struct sway_container *container,
+		struct sway_container_state *state) {
+	state->layout = container->layout;
+	state->swayc_x = container->x;
+	state->swayc_y = container->y;
+	state->swayc_width = container->width;
+	state->swayc_height = container->height;
+	state->has_gaps = container->has_gaps;
+	state->current_gaps = container->current_gaps;
+	state->gaps_inner = container->gaps_inner;
+	state->gaps_outer = container->gaps_outer;
+	state->parent = container->parent;
+
+	if (container->type == C_VIEW) {
+		struct sway_view *view = container->sway_view;
+		state->view_x = view->x;
+		state->view_y = view->y;
+		state->view_width = view->width;
+		state->view_height = view->height;
+		state->is_fullscreen = view->is_fullscreen;
+		state->border = view->border;
+		state->border_thickness = view->border_thickness;
+		state->border_top = view->border_top;
+		state->border_left = view->border_left;
+		state->border_right = view->border_right;
+		state->border_bottom = view->border_bottom;
+	} else if (container->type == C_WORKSPACE) {
+		state->ws_fullscreen = container->sway_workspace->fullscreen;
+		state->ws_floating = container->sway_workspace->floating;
+		state->children = create_list();
+		list_cat(state->children, container->children);
+	} else {
+		state->children = create_list();
+		list_cat(state->children, container->children);
+	}
+}
+
+static bool transaction_has_container(struct sway_transaction *transaction,
+		struct sway_container *container) {
+	for (int i = 0; i < transaction->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			transaction->instructions->items[i];
+		if (instruction->container == container) {
+			return true;
+		}
+	}
+	return false;
+}
+
+void transaction_add_container(struct sway_transaction *transaction,
+		struct sway_container *container) {
+	if (transaction_has_container(transaction, container)) {
+		return;
+	}
+	struct sway_transaction_instruction *instruction =
+		calloc(1, sizeof(struct sway_transaction_instruction));
+	instruction->transaction = transaction;
+	instruction->container = container;
+
+	copy_pending_state(container, &instruction->state);
+
+	if (container->type == C_VIEW) {
+		save_view_buffer(container->sway_view, instruction);
+	}
+	list_add(transaction->instructions, instruction);
+}
+
+/**
+ * Apply a transaction to the "current" state of the tree.
+ */
+static void transaction_apply(struct sway_transaction *transaction) {
+	wlr_log(L_DEBUG, "Applying transaction %p", transaction);
+	if (server.debug_txn_timings) {
+		struct timespec now;
+		clock_gettime(CLOCK_MONOTONIC, &now);
+		struct timespec *create = &transaction->create_time;
+		struct timespec *commit = &transaction->commit_time;
+		float ms_arranging = (commit->tv_sec - create->tv_sec) * 1000 +
+			(commit->tv_nsec - create->tv_nsec) / 1000000.0;
+		float ms_waiting = (now.tv_sec - commit->tv_sec) * 1000 +
+			(now.tv_nsec - commit->tv_nsec) / 1000000.0;
+		float ms_total = ms_arranging + ms_waiting;
+		wlr_log(L_DEBUG, "Transaction %p: %.1fms arranging, %.1fms waiting, "
+				"%.1fms total (%.1f frames if 60Hz)", transaction,
+				ms_arranging, ms_waiting, ms_total, ms_total / (1000 / 60));
+	}
+
+	// Apply the instruction state to the container's current state
+	for (int i = 0; i < transaction->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			transaction->instructions->items[i];
+		struct sway_container *container = instruction->container;
+
+		// Damage the old and new locations
+		struct wlr_box old_box = {
+			.x = container->current.swayc_x,
+			.y = container->current.swayc_y,
+			.width = container->current.swayc_width,
+			.height = container->current.swayc_height,
+		};
+		struct wlr_box new_box = {
+			.x = instruction->state.swayc_x,
+			.y = instruction->state.swayc_y,
+			.width = instruction->state.swayc_width,
+			.height = instruction->state.swayc_height,
+		};
+		for (int j = 0; j < root_container.children->length; ++j) {
+			struct sway_container *output = root_container.children->items[j];
+			output_damage_box(output->sway_output, &old_box);
+			output_damage_box(output->sway_output, &new_box);
+		}
+
+		// There are separate children lists for each instruction state, the
+		// container's current state and the container's pending state
+		// (ie. con->children). The list itself needs to be freed here.
+		// Any child containers which are being deleted will be cleaned up in
+		// transaction_destroy().
+		list_free(container->current.children);
+
+		memcpy(&container->current, &instruction->state,
+				sizeof(struct sway_container_state));
+	}
+}
+
+/**
+ * For simplicity, we only progress the queue if it can be completely flushed.
+ */
+static void transaction_progress_queue() {
+	// We iterate this list in reverse because we're more likely to find a
+	// waiting transactions at the end of the list.
+	for (int i = server.transactions->length - 1; i >= 0; --i) {
+		struct sway_transaction *transaction = server.transactions->items[i];
+		if (transaction->num_waiting) {
+			return;
+		}
+	}
+	for (int i = 0; i < server.transactions->length; ++i) {
+		struct sway_transaction *transaction = server.transactions->items[i];
+		transaction_apply(transaction);
+		transaction_destroy(transaction);
+	}
+	server.transactions->length = 0;
+}
+
+static int handle_timeout(void *data) {
+	struct sway_transaction *transaction = data;
+	wlr_log(L_DEBUG, "Transaction %p timed out (%li waiting)",
+			transaction, transaction->num_waiting);
+	transaction->num_waiting = 0;
+	transaction_progress_queue();
+	return 0;
+}
+
+static bool should_configure(struct sway_container *con,
+		struct sway_transaction_instruction *instruction) {
+	if (con->type != C_VIEW) {
+		return false;
+	}
+	if (con->destroying) {
+		return false;
+	}
+	// The settled dimensions are what size the view will be once any pending
+	// configures have applied (excluding the one we might be configuring now).
+	// If these match the dimensions that this transaction wants then we don't
+	// need to configure it.
+	int settled_width = con->current.view_width;
+	int settled_height = con->current.view_height;
+	if (con->instructions->length) {
+		struct sway_transaction_instruction *last_instruction =
+			con->instructions->items[con->instructions->length - 1];
+		settled_width = last_instruction->state.view_width;
+		settled_height = last_instruction->state.view_height;
+	}
+	if (settled_width == instruction->state.view_width &&
+			settled_height == instruction->state.view_height) {
+		return false;
+	}
+	return true;
+}
+
+void transaction_commit(struct sway_transaction *transaction) {
+	wlr_log(L_DEBUG, "Transaction %p committing with %i instructions",
+			transaction, transaction->instructions->length);
+	transaction->num_waiting = 0;
+	for (int i = 0; i < transaction->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			transaction->instructions->items[i];
+		struct sway_container *con = instruction->container;
+		if (should_configure(con, instruction)) {
+			instruction->serial = view_configure(con->sway_view,
+					instruction->state.view_x,
+					instruction->state.view_y,
+					instruction->state.view_width,
+					instruction->state.view_height);
+			++transaction->num_waiting;
+
+			// From here on we are rendering a saved buffer of the view, which
+			// means we can send a frame done event to make the client redraw it
+			// as soon as possible. Additionally, this is required if a view is
+			// mapping and its default geometry doesn't intersect an output.
+			struct timespec when;
+			wlr_surface_send_frame_done(con->sway_view->surface, &when);
+		}
+		list_add(con->instructions, instruction);
+	}
+	transaction->num_configures = transaction->num_waiting;
+	if (server.debug_txn_timings) {
+		clock_gettime(CLOCK_MONOTONIC, &transaction->commit_time);
+	}
+	if (server.transactions->length || transaction->num_waiting) {
+		list_add(server.transactions, transaction);
+	} else {
+		// There are no other transactions in progress, and this one has nothing
+		// to wait for, so we can skip the queue.
+		wlr_log(L_DEBUG, "Transaction %p has nothing to wait for", transaction);
+		transaction_apply(transaction);
+		transaction_destroy(transaction);
+		return;
+	}
+
+	if (transaction->num_waiting) {
+		// Set up a timer which the views must respond within
+		transaction->timer = wl_event_loop_add_timer(server.wl_event_loop,
+				handle_timeout, transaction);
+		wl_event_source_timer_update(transaction->timer, TIMEOUT_MS);
+	}
+
+	// The debug tree shows the pending/live tree. Here is a good place to
+	// update it, because we make a transaction every time we change the pending
+	// tree.
+	update_debug_tree();
+}
+
+static void set_instruction_ready(
+		struct sway_transaction_instruction *instruction) {
+	instruction->ready = true;
+	struct sway_transaction *transaction = instruction->transaction;
+
+	if (server.debug_txn_timings) {
+		struct timespec now;
+		clock_gettime(CLOCK_MONOTONIC, &now);
+		struct timespec *start = &transaction->commit_time;
+		float ms = (now.tv_sec - start->tv_sec) * 1000 +
+			(now.tv_nsec - start->tv_nsec) / 1000000.0;
+		wlr_log(L_DEBUG, "Transaction %p: %li/%li ready in %.1fms (%s)",
+				transaction,
+				transaction->num_configures - transaction->num_waiting + 1,
+				transaction->num_configures, ms,
+				instruction->container->name);
+
+	}
+
+	// If all views are ready, apply the transaction.
+	// If the transaction has timed out then its num_waiting will be 0 already.
+	if (transaction->num_waiting > 0 && --transaction->num_waiting == 0) {
+#if !TRANSACTION_DEBUG
+		wlr_log(L_DEBUG, "Transaction %p is ready", transaction);
+		wl_event_source_timer_update(transaction->timer, 0);
+		transaction_progress_queue();
+#endif
+	}
+}
+
+/**
+ * Mark all of the view's instructions as ready up to and including the
+ * instruction at the given index. This allows the view to skip a configure.
+ */
+static void set_instructions_ready(struct sway_view *view, int index) {
+	for (int i = 0; i <= index; ++i) {
+		struct sway_transaction_instruction *instruction =
+			view->swayc->instructions->items[i];
+		set_instruction_ready(instruction);
+	}
+}
+
+void transaction_notify_view_ready(struct sway_view *view, uint32_t serial) {
+	for (int i = 0; i < view->swayc->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			view->swayc->instructions->items[i];
+		if (instruction->serial == serial && !instruction->ready) {
+			set_instructions_ready(view, i);
+			return;
+		}
+	}
+}
+
+void transaction_notify_view_ready_by_size(struct sway_view *view,
+		int width, int height) {
+	for (int i = 0; i < view->swayc->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			view->swayc->instructions->items[i];
+		if (!instruction->ready && instruction->state.view_width == width &&
+				instruction->state.view_height == height) {
+			set_instructions_ready(view, i);
+			return;
+		}
+	}
+}
+
+struct wlr_texture *transaction_get_saved_texture(struct sway_view *view,
+		int *width, int *height) {
+	struct sway_transaction_instruction *instruction =
+		view->swayc->instructions->items[0];
+	if (!instruction->saved_buffer) {
+		return NULL;
+	}
+	*width = instruction->saved_buffer_width;
+	*height = instruction->saved_buffer_height;
+	return instruction->saved_buffer->texture;
+}

sway/desktop/xdg_shell.c

@@ -8,6 +8,7 @@
 #include "sway/input/input-manager.h"
 #include "sway/input/seat.h"
 #include "sway/server.h"
+#include "sway/tree/arrange.h"
 #include "sway/tree/container.h"
 #include "sway/tree/layout.h"
 #include "sway/tree/view.h"
@@ -87,18 +88,14 @@ static const char *get_string_prop(struct sway_view *view, enum sway_view_prop p
 	}
 }
 
-static void configure(struct sway_view *view, double lx, double ly, int width,
+static uint32_t configure(struct sway_view *view, double lx, double ly,
-		int height) {
+		int width, int height) {
 	struct sway_xdg_shell_view *xdg_shell_view =
 		xdg_shell_view_from_view(view);
 	if (xdg_shell_view == NULL) {
-		return;
+		return 0;
 	}
-
+	return wlr_xdg_toplevel_set_size(view->wlr_xdg_surface, width, height);
-	xdg_shell_view->pending_width = width;
-	xdg_shell_view->pending_height = height;
-	wlr_xdg_toplevel_set_size(view->wlr_xdg_surface, width, height);
-	view_update_position(view, lx, ly);
 }
 
 static void set_activated(struct sway_view *view, bool activated) {
@@ -166,10 +163,6 @@ static void destroy(struct sway_view *view) {
 	if (xdg_shell_view == NULL) {
 		return;
 	}
-	wl_list_remove(&xdg_shell_view->destroy.link);
-	wl_list_remove(&xdg_shell_view->map.link);
-	wl_list_remove(&xdg_shell_view->unmap.link);
-	wl_list_remove(&xdg_shell_view->request_fullscreen.link);
 	free(xdg_shell_view);
 }
 
@@ -189,18 +182,16 @@ static void handle_commit(struct wl_listener *listener, void *data) {
 	struct sway_xdg_shell_view *xdg_shell_view =
 		wl_container_of(listener, xdg_shell_view, commit);
 	struct sway_view *view = &xdg_shell_view->view;
-	if (view->swayc && container_is_floating(view->swayc)) {
+	struct wlr_xdg_surface *xdg_surface = view->wlr_xdg_surface;
-		int width = view->wlr_xdg_surface->geometry.width;
+
-		int height = view->wlr_xdg_surface->geometry.height;
+	if (!view->swayc) {
-		if (!width && !height) {
+		return;
-			width = view->wlr_xdg_surface->surface->current->width;
-			height = view->wlr_xdg_surface->surface->current->height;
-		}
-		view_update_size(view, width, height);
-	} else {
-		view_update_size(view, xdg_shell_view->pending_width,
-				xdg_shell_view->pending_height);
 	}
+
+	if (view->swayc->instructions->length) {
+		transaction_notify_view_ready(view, xdg_surface->configure_serial);
+	}
+
 	view_update_title(view, false);
 	view_damage_from(view);
 }
@@ -215,8 +206,13 @@ static void handle_new_popup(struct wl_listener *listener, void *data) {
 static void handle_unmap(struct wl_listener *listener, void *data) {
 	struct sway_xdg_shell_view *xdg_shell_view =
 		wl_container_of(listener, xdg_shell_view, unmap);
+	struct sway_view *view = &xdg_shell_view->view;
 
-	view_unmap(&xdg_shell_view->view);
+	if (!sway_assert(view->surface, "Cannot unmap unmapped view")) {
+		return;
+	}
+
+	view_unmap(view);
 
 	wl_list_remove(&xdg_shell_view->commit.link);
 	wl_list_remove(&xdg_shell_view->new_popup.link);
@@ -234,8 +230,17 @@ static void handle_map(struct wl_listener *listener, void *data) {
 		view->natural_width = view->wlr_xdg_surface->surface->current->width;
 		view->natural_height = view->wlr_xdg_surface->surface->current->height;
 	}
+
 	view_map(view, view->wlr_xdg_surface->surface);
 
+	if (xdg_surface->toplevel->client_pending.fullscreen) {
+		view_set_fullscreen(view, true);
+		struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
+		arrange_and_commit(ws);
+	} else {
+		arrange_and_commit(view->swayc->parent);
+	}
+
 	xdg_shell_view->commit.notify = handle_commit;
 	wl_signal_add(&xdg_surface->surface->events.commit,
 		&xdg_shell_view->commit);
@@ -243,16 +248,22 @@ static void handle_map(struct wl_listener *listener, void *data) {
 	xdg_shell_view->new_popup.notify = handle_new_popup;
 	wl_signal_add(&xdg_surface->events.new_popup,
 		&xdg_shell_view->new_popup);
-
-	if (xdg_surface->toplevel->client_pending.fullscreen) {
-		view_set_fullscreen(view, true);
-	}
 }
 
 static void handle_destroy(struct wl_listener *listener, void *data) {
 	struct sway_xdg_shell_view *xdg_shell_view =
 		wl_container_of(listener, xdg_shell_view, destroy);
-	view_destroy(&xdg_shell_view->view);
+	struct sway_view *view = &xdg_shell_view->view;
+	if (!sway_assert(view->swayc == NULL || view->swayc->destroying,
+				"Tried to destroy a mapped view")) {
+		return;
+	}
+	wl_list_remove(&xdg_shell_view->destroy.link);
+	wl_list_remove(&xdg_shell_view->map.link);
+	wl_list_remove(&xdg_shell_view->unmap.link);
+	wl_list_remove(&xdg_shell_view->request_fullscreen.link);
+	view->wlr_xdg_surface = NULL;
+	view_destroy(view);
 }
 
 static void handle_request_fullscreen(struct wl_listener *listener, void *data) {
@@ -261,6 +272,7 @@ static void handle_request_fullscreen(struct wl_listener *listener, void *data)
 	struct wlr_xdg_toplevel_set_fullscreen_event *e = data;
 	struct wlr_xdg_surface *xdg_surface =
 		xdg_shell_view->view.wlr_xdg_surface;
+	struct sway_view *view = &xdg_shell_view->view;
 
 	if (!sway_assert(xdg_surface->role == WLR_XDG_SURFACE_ROLE_TOPLEVEL,
 				"xdg_shell requested fullscreen of surface with role %i",
@@ -271,7 +283,10 @@ static void handle_request_fullscreen(struct wl_listener *listener, void *data)
 		return;
 	}
 
-	view_set_fullscreen(&xdg_shell_view->view, e->fullscreen);
+	view_set_fullscreen(view, e->fullscreen);
+
+	struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
+	arrange_and_commit(ws);
 }
 
 void handle_xdg_shell_surface(struct wl_listener *listener, void *data) {

sway/desktop/xdg_shell_v6.c

@@ -3,9 +3,10 @@
 #include <stdlib.h>
 #include <wayland-server.h>
 #include <wlr/types/wlr_xdg_shell_v6.h>
+#include "sway/server.h"
+#include "sway/tree/arrange.h"
 #include "sway/tree/container.h"
 #include "sway/tree/layout.h"
-#include "sway/server.h"
 #include "sway/tree/view.h"
 #include "sway/input/seat.h"
 #include "sway/input/input-manager.h"
@@ -86,18 +87,15 @@ static const char *get_string_prop(struct sway_view *view, enum sway_view_prop p
 	}
 }
 
-static void configure(struct sway_view *view, double lx, double ly, int width,
+static uint32_t configure(struct sway_view *view, double lx, double ly,
-		int height) {
+		int width, int height) {
 	struct sway_xdg_shell_v6_view *xdg_shell_v6_view =
 		xdg_shell_v6_view_from_view(view);
 	if (xdg_shell_v6_view == NULL) {
-		return;
+		return 0;
 	}
-
+	return wlr_xdg_toplevel_v6_set_size(
-	xdg_shell_v6_view->pending_width = width;
+			view->wlr_xdg_surface_v6, width, height);
-	xdg_shell_v6_view->pending_height = height;
-	wlr_xdg_toplevel_v6_set_size(view->wlr_xdg_surface_v6, width, height);
-	view_update_position(view, lx, ly);
 }
 
 static void set_activated(struct sway_view *view, bool activated) {
@@ -161,10 +159,6 @@ static void destroy(struct sway_view *view) {
 	if (xdg_shell_v6_view == NULL) {
 		return;
 	}
-	wl_list_remove(&xdg_shell_v6_view->destroy.link);
-	wl_list_remove(&xdg_shell_v6_view->map.link);
-	wl_list_remove(&xdg_shell_v6_view->unmap.link);
-	wl_list_remove(&xdg_shell_v6_view->request_fullscreen.link);
 	free(xdg_shell_v6_view);
 }
 
@@ -184,18 +178,15 @@ static void handle_commit(struct wl_listener *listener, void *data) {
 	struct sway_xdg_shell_v6_view *xdg_shell_v6_view =
 		wl_container_of(listener, xdg_shell_v6_view, commit);
 	struct sway_view *view = &xdg_shell_v6_view->view;
-	if (view->swayc && container_is_floating(view->swayc)) {
+	struct wlr_xdg_surface_v6 *xdg_surface_v6 = view->wlr_xdg_surface_v6;
-		int width = view->wlr_xdg_surface_v6->geometry.width;
+
-		int height = view->wlr_xdg_surface_v6->geometry.height;
+	if (!view->swayc) {
-		if (!width && !height) {
+		return;
-			width = view->wlr_xdg_surface_v6->surface->current->width;
-			height = view->wlr_xdg_surface_v6->surface->current->height;
-		}
-		view_update_size(view, width, height);
-	} else {
-		view_update_size(view, xdg_shell_v6_view->pending_width,
-				xdg_shell_v6_view->pending_height);
 	}
+	if (view->swayc->instructions->length) {
+		transaction_notify_view_ready(view, xdg_surface_v6->configure_serial);
+	}
+
 	view_update_title(view, false);
 	view_damage_from(view);
 }
@@ -210,8 +201,13 @@ static void handle_new_popup(struct wl_listener *listener, void *data) {
 static void handle_unmap(struct wl_listener *listener, void *data) {
 	struct sway_xdg_shell_v6_view *xdg_shell_v6_view =
 		wl_container_of(listener, xdg_shell_v6_view, unmap);
+	struct sway_view *view = &xdg_shell_v6_view->view;
 
-	view_unmap(&xdg_shell_v6_view->view);
+	if (!sway_assert(view->surface, "Cannot unmap unmapped view")) {
+		return;
+	}
+
+	view_unmap(view);
 
 	wl_list_remove(&xdg_shell_v6_view->commit.link);
 	wl_list_remove(&xdg_shell_v6_view->new_popup.link);
@@ -229,8 +225,17 @@ static void handle_map(struct wl_listener *listener, void *data) {
 		view->natural_width = view->wlr_xdg_surface_v6->surface->current->width;
 		view->natural_height = view->wlr_xdg_surface_v6->surface->current->height;
 	}
+
 	view_map(view, view->wlr_xdg_surface_v6->surface);
 
+	if (xdg_surface->toplevel->client_pending.fullscreen) {
+		view_set_fullscreen(view, true);
+		struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
+		arrange_and_commit(ws);
+	} else {
+		arrange_and_commit(view->swayc->parent);
+	}
+
 	xdg_shell_v6_view->commit.notify = handle_commit;
 	wl_signal_add(&xdg_surface->surface->events.commit,
 		&xdg_shell_v6_view->commit);
@@ -238,16 +243,18 @@ static void handle_map(struct wl_listener *listener, void *data) {
 	xdg_shell_v6_view->new_popup.notify = handle_new_popup;
 	wl_signal_add(&xdg_surface->events.new_popup,
 		&xdg_shell_v6_view->new_popup);
-
-	if (xdg_surface->toplevel->client_pending.fullscreen) {
-		view_set_fullscreen(view, true);
-	}
 }
 
 static void handle_destroy(struct wl_listener *listener, void *data) {
 	struct sway_xdg_shell_v6_view *xdg_shell_v6_view =
 		wl_container_of(listener, xdg_shell_v6_view, destroy);
-	view_destroy(&xdg_shell_v6_view->view);
+	struct sway_view *view = &xdg_shell_v6_view->view;
+	wl_list_remove(&xdg_shell_v6_view->destroy.link);
+	wl_list_remove(&xdg_shell_v6_view->map.link);
+	wl_list_remove(&xdg_shell_v6_view->unmap.link);
+	wl_list_remove(&xdg_shell_v6_view->request_fullscreen.link);
+	view->wlr_xdg_surface_v6 = NULL;
+	view_destroy(view);
 }
 
 static void handle_request_fullscreen(struct wl_listener *listener, void *data) {
@@ -256,6 +263,7 @@ static void handle_request_fullscreen(struct wl_listener *listener, void *data)
 	struct wlr_xdg_toplevel_v6_set_fullscreen_event *e = data;
 	struct wlr_xdg_surface_v6 *xdg_surface =
 		xdg_shell_v6_view->view.wlr_xdg_surface_v6;
+	struct sway_view *view = &xdg_shell_v6_view->view;
 
 	if (!sway_assert(xdg_surface->role == WLR_XDG_SURFACE_V6_ROLE_TOPLEVEL,
 				"xdg_shell_v6 requested fullscreen of surface with role %i",
@@ -266,7 +274,10 @@ static void handle_request_fullscreen(struct wl_listener *listener, void *data)
 		return;
 	}
 
-	view_set_fullscreen(&xdg_shell_v6_view->view, e->fullscreen);
+	view_set_fullscreen(view, e->fullscreen);
+
+	struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
+	arrange_and_commit(ws);
 }
 
 void handle_xdg_shell_v6_surface(struct wl_listener *listener, void *data) {

sway/desktop/xwayland.c

@@ -7,10 +7,12 @@
 #include <wlr/xwayland.h>
 #include "log.h"
 #include "sway/desktop.h"
+#include "sway/desktop/transaction.h"
 #include "sway/input/input-manager.h"
 #include "sway/input/seat.h"
 #include "sway/output.h"
 #include "sway/server.h"
+#include "sway/tree/arrange.h"
 #include "sway/tree/container.h"
 #include "sway/tree/layout.h"
 #include "sway/tree/view.h"
@@ -176,19 +178,18 @@ static uint32_t get_int_prop(struct sway_view *view, enum sway_view_prop prop) {
 	}
 }
 
-static void configure(struct sway_view *view, double lx, double ly, int width,
+static uint32_t configure(struct sway_view *view, double lx, double ly, int width,
 		int height) {
 	struct sway_xwayland_view *xwayland_view = xwayland_view_from_view(view);
 	if (xwayland_view == NULL) {
-		return;
+		return 0;
 	}
 	struct wlr_xwayland_surface *xsurface = view->wlr_xwayland_surface;
 
-	xwayland_view->pending_lx = lx;
-	xwayland_view->pending_ly = ly;
-	xwayland_view->pending_width = width;
-	xwayland_view->pending_height = height;
 	wlr_xwayland_surface_configure(xsurface, lx, ly, width, height);
+
+	// xwayland doesn't give us a serial for the configure
+	return 0;
 }
 
 static void set_activated(struct sway_view *view, bool activated) {
@@ -257,14 +258,6 @@ static void destroy(struct sway_view *view) {
 	if (xwayland_view == NULL) {
 		return;
 	}
-	wl_list_remove(&xwayland_view->destroy.link);
-	wl_list_remove(&xwayland_view->request_configure.link);
-	wl_list_remove(&xwayland_view->request_fullscreen.link);
-	wl_list_remove(&xwayland_view->set_title.link);
-	wl_list_remove(&xwayland_view->set_class.link);
-	wl_list_remove(&xwayland_view->set_window_type.link);
-	wl_list_remove(&xwayland_view->map.link);
-	wl_list_remove(&xwayland_view->unmap.link);
 	free(xwayland_view);
 }
 
@@ -285,22 +278,27 @@ static void handle_commit(struct wl_listener *listener, void *data) {
 		wl_container_of(listener, xwayland_view, commit);
 	struct sway_view *view = &xwayland_view->view;
 	struct wlr_xwayland_surface *xsurface = view->wlr_xwayland_surface;
-	if (view->swayc && container_is_floating(view->swayc)) {
+	struct wlr_surface_state *surface_state = xsurface->surface->current;
-		view_update_size(view, xsurface->width, xsurface->height);
+
-	} else {
+	if (view->swayc->instructions->length) {
-		view_update_size(view, xwayland_view->pending_width,
+		transaction_notify_view_ready_by_size(view,
-				xwayland_view->pending_height);
+				surface_state->width, surface_state->height);
 	}
-	view_update_position(view,
-			xwayland_view->pending_lx, xwayland_view->pending_ly);
 	view_damage_from(view);
 }
 
 static void handle_unmap(struct wl_listener *listener, void *data) {
 	struct sway_xwayland_view *xwayland_view =
 		wl_container_of(listener, xwayland_view, unmap);
+	struct sway_view *view = &xwayland_view->view;
+
+	if (!sway_assert(view->surface, "Cannot unmap unmapped view")) {
+		return;
+	}
+
+	view_unmap(view);
+
 	wl_list_remove(&xwayland_view->commit.link);
-	view_unmap(&xwayland_view->view);
 }
 
 static void handle_map(struct wl_listener *listener, void *data) {
@@ -322,12 +320,31 @@ static void handle_map(struct wl_listener *listener, void *data) {
 
 	if (xsurface->fullscreen) {
 		view_set_fullscreen(view, true);
+		struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
+		arrange_and_commit(ws);
+	} else {
+		arrange_and_commit(view->swayc->parent);
 	}
 }
 
 static void handle_destroy(struct wl_listener *listener, void *data) {
 	struct sway_xwayland_view *xwayland_view =
 		wl_container_of(listener, xwayland_view, destroy);
+	struct sway_view *view = &xwayland_view->view;
+
+	if (view->surface) {
+		view_unmap(view);
+		wl_list_remove(&xwayland_view->commit.link);
+	}
+
+	wl_list_remove(&xwayland_view->destroy.link);
+	wl_list_remove(&xwayland_view->request_configure.link);
+	wl_list_remove(&xwayland_view->request_fullscreen.link);
+	wl_list_remove(&xwayland_view->set_title.link);
+	wl_list_remove(&xwayland_view->set_class.link);
+	wl_list_remove(&xwayland_view->set_window_type.link);
+	wl_list_remove(&xwayland_view->map.link);
+	wl_list_remove(&xwayland_view->unmap.link);
 	view_destroy(&xwayland_view->view);
 }
 
@@ -343,10 +360,12 @@ static void handle_request_configure(struct wl_listener *listener, void *data) {
 		return;
 	}
 	if (container_is_floating(view->swayc)) {
-		configure(view, view->x, view->y, ev->width, ev->height);
+		configure(view, view->swayc->current.view_x,
+				view->swayc->current.view_y, ev->width, ev->height);
 	} else {
-		configure(view, view->x, view->y,
+		configure(view, view->swayc->current.view_x,
-			view->width, view->height);
+				view->swayc->current.view_y, view->swayc->current.view_width,
+				view->swayc->current.view_height);
 	}
 }
 
@@ -359,6 +378,9 @@ static void handle_request_fullscreen(struct wl_listener *listener, void *data)
 		return;
 	}
 	view_set_fullscreen(view, xsurface->fullscreen);
+
+	struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
+	arrange_and_commit(ws);
 }
 
 static void handle_set_title(struct wl_listener *listener, void *data) {

sway/input/seat.c

@@ -830,6 +830,18 @@ struct sway_container *seat_get_active_child(struct sway_seat *seat,
 	return NULL;
 }
 
+struct sway_container *seat_get_active_current_child(struct sway_seat *seat,
+		struct sway_container *container) {
+	struct sway_container *child = seat_get_active_child(seat, container);
+	if (child) {
+		return child;
+	}
+	if (container->current.children->length == 1) {
+		return container->current.children->items[0];
+	}
+	return NULL;
+}
+
 struct sway_container *seat_get_focus(struct sway_seat *seat) {
 	if (!seat->has_focus) {
 		return NULL;

sway/meson.build

@@ -12,6 +12,7 @@ sway_sources = files(
 	'desktop/desktop.c',
 	'desktop/layer_shell.c',
 	'desktop/output.c',
+	'desktop/transaction.c',
 	'desktop/xdg_shell_v6.c',
 	'desktop/xdg_shell.c',
 	'desktop/xwayland.c',

sway/server.c

@@ -19,6 +19,7 @@
 #include <wlr/types/wlr_xdg_output.h>
 #include <wlr/util/log.h>
 // TODO WLR: make Xwayland optional
+#include "list.h"
 #include "sway/config.h"
 #include "sway/input/input-manager.h"
 #include "sway/server.h"
@@ -114,6 +115,14 @@ bool server_init(struct sway_server *server) {
 		return false;
 	}
 
+	const char *debug = getenv("SWAY_DEBUG");
+	if (debug != NULL && strcmp(debug, "txn_timings") == 0) {
+		server->debug_txn_timings = true;
+	}
+	server->destroying_containers = create_list();
+
+	server->transactions = create_list();
+
 	input_manager = input_manager_create(server);
 	return true;
 }
@@ -121,6 +130,8 @@ bool server_init(struct sway_server *server) {
 void server_fini(struct sway_server *server) {
 	// TODO: free sway-specific resources
 	wl_display_destroy(server->wl_display);
+	list_free(server->destroying_containers);
+	list_free(server->transactions);
 }
 
 void server_run(struct sway_server *server) {

sway/tree/arrange.c

@@ -5,7 +5,6 @@
 #include <string.h>
 #include <wlr/types/wlr_output.h>
 #include <wlr/types/wlr_output_layout.h>
-#include "sway/debug.h"
 #include "sway/tree/arrange.h"
 #include "sway/tree/container.h"
 #include "sway/tree/layout.h"
@@ -17,7 +16,253 @@
 
 struct sway_container root_container;
 
-void arrange_root() {
+static void apply_horiz_layout(struct sway_container *parent) {
+	size_t num_children = parent->children->length;
+	if (!num_children) {
+		return;
+	}
+	size_t parent_offset = 0;
+	if (parent->parent->layout == L_TABBED) {
+		parent_offset = container_titlebar_height();
+	} else if (parent->parent->layout == L_STACKED) {
+		parent_offset = container_titlebar_height() *
+			parent->parent->children->length;
+	}
+	size_t parent_height = parent->height - parent_offset;
+
+	// Calculate total width of children
+	double total_width = 0;
+	for (size_t i = 0; i < num_children; ++i) {
+		struct sway_container *child = parent->children->items[i];
+		if (child->width <= 0) {
+			if (num_children > 1) {
+				child->width = parent->width / (num_children - 1);
+			} else {
+				child->width = parent->width;
+			}
+		}
+		remove_gaps(child);
+		total_width += child->width;
+	}
+	double scale = parent->width / total_width;
+
+	// Resize windows
+	wlr_log(L_DEBUG, "Arranging %p horizontally", parent);
+	double child_x = parent->x;
+	for (size_t i = 0; i < num_children; ++i) {
+		struct sway_container *child = parent->children->items[i];
+		wlr_log(L_DEBUG,
+				"Calculating arrangement for %p:%d (will scale %f by %f)",
+				child, child->type, child->width, scale);
+		child->x = child_x;
+		child->y = parent->y + parent_offset;
+		child->width = floor(child->width * scale);
+		child->height = parent_height;
+		child_x += child->width;
+
+		// Make last child use remaining width of parent
+		if (i == num_children - 1) {
+			child->width = parent->x + parent->width - child->x;
+		}
+		add_gaps(child);
+	}
+}
+
+static void apply_vert_layout(struct sway_container *parent) {
+	size_t num_children = parent->children->length;
+	if (!num_children) {
+		return;
+	}
+	size_t parent_offset = 0;
+	if (parent->parent->layout == L_TABBED) {
+		parent_offset = container_titlebar_height();
+	} else if (parent->parent->layout == L_STACKED) {
+		parent_offset =
+			container_titlebar_height() * parent->parent->children->length;
+	}
+	size_t parent_height = parent->height + parent_offset;
+
+	// Calculate total height of children
+	double total_height = 0;
+	for (size_t i = 0; i < num_children; ++i) {
+		struct sway_container *child = parent->children->items[i];
+		if (child->height <= 0) {
+			if (num_children > 1) {
+				child->height = parent_height / (num_children - 1);
+			} else {
+				child->height = parent_height;
+			}
+		}
+		remove_gaps(child);
+		total_height += child->height;
+	}
+	double scale = parent_height / total_height;
+
+	// Resize
+	wlr_log(L_DEBUG, "Arranging %p vertically", parent);
+	double child_y = parent->y + parent_offset;
+	for (size_t i = 0; i < num_children; ++i) {
+		struct sway_container *child = parent->children->items[i];
+		wlr_log(L_DEBUG,
+				"Calculating arrangement for %p:%d (will scale %f by %f)",
+				child, child->type, child->height, scale);
+		child->x = parent->x;
+		child->y = child_y;
+		child->width = parent->width;
+		child->height = floor(child->height * scale);
+		child_y += child->height;
+
+		// Make last child use remaining height of parent
+		if (i == num_children - 1) {
+			child->height =
+				parent->y + parent_offset + parent_height - child->y;
+		}
+		add_gaps(child);
+	}
+}
+
+static void apply_tabbed_or_stacked_layout(struct sway_container *parent) {
+	if (!parent->children->length) {
+		return;
+	}
+	size_t parent_offset = 0;
+	if (parent->parent->layout == L_TABBED) {
+		parent_offset = container_titlebar_height();
+	} else if (parent->parent->layout == L_STACKED) {
+		parent_offset =
+			container_titlebar_height() * parent->parent->children->length;
+	}
+	size_t parent_height = parent->height - parent_offset;
+	for (int i = 0; i < parent->children->length; ++i) {
+		struct sway_container *child = parent->children->items[i];
+		remove_gaps(child);
+		child->x = parent->x;
+		child->y = parent->y + parent_offset;
+		child->width = parent->width;
+		child->height = parent_height;
+		add_gaps(child);
+	}
+}
+
+/**
+ * If a container has been deleted from the pending tree state, we must add it
+ * to the transaction so it can be freed afterwards. To do this, we iterate the
+ * server's destroying_containers list and add all of them. We may add more than
+ * what we need to, but this is easy and has no negative consequences.
+ */
+static void add_deleted_containers(struct sway_transaction *transaction) {
+	for (int i = 0; i < server.destroying_containers->length; ++i) {
+		struct sway_container *child = server.destroying_containers->items[i];
+		transaction_add_container(transaction, child);
+	}
+}
+
+static void arrange_children_of(struct sway_container *parent,
+		struct sway_transaction *transaction);
+
+static void arrange_floating(struct sway_container *floating,
+		struct sway_transaction *transaction) {
+	for (int i = 0; i < floating->children->length; ++i) {
+		struct sway_container *floater = floating->children->items[i];
+		if (floater->type == C_VIEW) {
+			view_autoconfigure(floater->sway_view);
+		} else {
+			arrange_children_of(floater, transaction);
+		}
+		transaction_add_container(transaction, floater);
+	}
+	transaction_add_container(transaction, floating);
+}
+
+static void arrange_children_of(struct sway_container *parent,
+		struct sway_transaction *transaction) {
+	if (config->reloading) {
+		return;
+	}
+	wlr_log(L_DEBUG, "Arranging layout for %p %s %fx%f+%f,%f", parent,
+		parent->name, parent->width, parent->height, parent->x, parent->y);
+
+	// Calculate x, y, width and height of children
+	switch (parent->layout) {
+	case L_HORIZ:
+		apply_horiz_layout(parent);
+		break;
+	case L_VERT:
+		apply_vert_layout(parent);
+		break;
+	case L_TABBED:
+	case L_STACKED:
+		apply_tabbed_or_stacked_layout(parent);
+		break;
+	case L_NONE:
+		apply_horiz_layout(parent);
+		break;
+	case L_FLOATING:
+		arrange_floating(parent, transaction);
+		break;
+	}
+
+	// Recurse into child containers
+	for (int i = 0; i < parent->children->length; ++i) {
+		struct sway_container *child = parent->children->items[i];
+		if (parent->has_gaps && !child->has_gaps) {
+			child->has_gaps = true;
+			child->gaps_inner = parent->gaps_inner;
+			child->gaps_outer = parent->gaps_outer;
+		}
+		if (child->type == C_VIEW) {
+			view_autoconfigure(child->sway_view);
+		} else {
+			arrange_children_of(child, transaction);
+		}
+		transaction_add_container(transaction, child);
+	}
+}
+
+static void arrange_workspace(struct sway_container *workspace,
+		struct sway_transaction *transaction) {
+	if (config->reloading) {
+		return;
+	}
+	struct sway_container *output = workspace->parent;
+	struct wlr_box *area = &output->sway_output->usable_area;
+	wlr_log(L_DEBUG, "Usable area for ws: %dx%d@%d,%d",
+			area->width, area->height, area->x, area->y);
+	remove_gaps(workspace);
+	workspace->width = area->width;
+	workspace->height = area->height;
+	workspace->x = output->x + area->x;
+	workspace->y = output->y + area->y;
+	add_gaps(workspace);
+	transaction_add_container(transaction, workspace);
+	wlr_log(L_DEBUG, "Arranging workspace '%s' at %f, %f", workspace->name,
+			workspace->x, workspace->y);
+	arrange_floating(workspace->sway_workspace->floating, transaction);
+	arrange_children_of(workspace, transaction);
+}
+
+static void arrange_output(struct sway_container *output,
+		struct sway_transaction *transaction) {
+	if (config->reloading) {
+		return;
+	}
+	const struct wlr_box *output_box = wlr_output_layout_get_box(
+			root_container.sway_root->output_layout,
+			output->sway_output->wlr_output);
+	output->x = output_box->x;
+	output->y = output_box->y;
+	output->width = output_box->width;
+	output->height = output_box->height;
+	transaction_add_container(transaction, output);
+	wlr_log(L_DEBUG, "Arranging output '%s' at %f,%f",
+			output->name, output->x, output->y);
+	for (int i = 0; i < output->children->length; ++i) {
+		struct sway_container *workspace = output->children->items[i];
+		arrange_workspace(workspace, transaction);
+	}
+}
+
+static void arrange_root(struct sway_transaction *transaction) {
 	if (config->reloading) {
 		return;
 	}
@@ -29,64 +274,43 @@ void arrange_root() {
 	root_container.y = layout_box->y;
 	root_container.width = layout_box->width;
 	root_container.height = layout_box->height;
+	transaction_add_container(transaction, &root_container);
 	for (int i = 0; i < root_container.children->length; ++i) {
 		struct sway_container *output = root_container.children->items[i];
-		arrange_output(output);
+		arrange_output(output, transaction);
 	}
 }
 
-void arrange_output(struct sway_container *output) {
+void arrange_windows(struct sway_container *container,
-	if (config->reloading) {
+		struct sway_transaction *transaction) {
-		return;
+	switch (container->type) {
+	case C_ROOT:
+		arrange_root(transaction);
+		break;
+	case C_OUTPUT:
+		arrange_output(container, transaction);
+		break;
+	case C_WORKSPACE:
+		arrange_workspace(container, transaction);
+		break;
+	case C_CONTAINER:
+		arrange_children_of(container, transaction);
+		transaction_add_container(transaction, container);
+		break;
+	case C_VIEW:
+		view_autoconfigure(container->sway_view);
+		transaction_add_container(transaction, container);
+		break;
+	case C_TYPES:
+		break;
 	}
-	if (!sway_assert(output->type == C_OUTPUT,
+	add_deleted_containers(transaction);
-			"called arrange_output() on non-output container")) {
-		return;
-	}
-
-	const struct wlr_box *output_box = wlr_output_layout_get_box(
-			root_container.sway_root->output_layout,
-			output->sway_output->wlr_output);
-	output->x = output_box->x;
-	output->y = output_box->y;
-	output->width = output_box->width;
-	output->height = output_box->height;
-	wlr_log(L_DEBUG, "Arranging output '%s' at %f,%f",
-			output->name, output->x, output->y);
-	
-	for (int i = 0; i < output->children->length; ++i) {
-		struct sway_container *workspace = output->children->items[i];
-		arrange_workspace(workspace);
-	}
-	container_damage_whole(output);
 }
 
-void arrange_workspace(struct sway_container *workspace) {
+void arrange_and_commit(struct sway_container *container) {
-	if (config->reloading) {
+	struct sway_transaction *transaction = transaction_create();
-		return;
+	arrange_windows(container, transaction);
-	}
+	transaction_commit(transaction);
-	if (!sway_assert(workspace->type == C_WORKSPACE,
-			"called arrange_workspace() on non-workspace container")) {
-		return;
-	}
-
-	struct sway_container *output = workspace->parent;
-	struct wlr_box *area = &output->sway_output->usable_area;
-	wlr_log(L_DEBUG, "Usable area for ws: %dx%d@%d,%d",
-			area->width, area->height, area->x, area->y);
-
-	remove_gaps(workspace);
-
-	workspace->width = area->width;
-	workspace->height = area->height;
-	workspace->x = output->x + area->x;
-	workspace->y = output->y + area->y;
-
-	add_gaps(workspace);
-
-	wlr_log(L_DEBUG, "Arranging workspace '%s' at %f, %f",
-			workspace->name, workspace->x, workspace->y);
-	arrange_children_of(workspace);
 }
 
 void remove_gaps(struct sway_container *c) {
@@ -126,211 +350,3 @@ void add_gaps(struct sway_container *c) {
 
 	wlr_log(L_DEBUG, "Adding gaps: %p", c);
 }
-
-static void apply_horiz_layout(struct sway_container *parent) {
-	size_t num_children = parent->children->length;
-	if (!num_children) {
-		return;
-	}
-	size_t parent_offset = 0;
-	if (parent->parent->layout == L_TABBED) {
-		parent_offset = container_titlebar_height();
-	} else if (parent->parent->layout == L_STACKED) {
-		parent_offset =
-			container_titlebar_height() * parent->parent->children->length;
-	}
-	size_t parent_height = parent->height - parent_offset;
-
-	// Calculate total width of children
-	double total_width = 0;
-	for (size_t i = 0; i < num_children; ++i) {
-		struct sway_container *child = parent->children->items[i];
-
-		if (child->width <= 0) {
-			if (num_children > 1) {
-				child->width = parent->width / (num_children - 1);
-			} else {
-				child->width = parent->width;
-			}
-		}
-		remove_gaps(child);
-		total_width += child->width;
-	}
-	double scale = parent->width / total_width;
-
-	// Resize windows
-	wlr_log(L_DEBUG, "Arranging %p horizontally", parent);
-	double child_x = parent->x;
-	struct sway_container *child;
-	for (size_t i = 0; i < num_children; ++i) {
-		child = parent->children->items[i];
-		wlr_log(L_DEBUG,
-				"Calculating arrangement for %p:%d (will scale %f by %f)",
-				child, child->type, child->width, scale);
-		child->x = child_x;
-		child->y = parent->y + parent_offset;
-		child->height = parent_height;
-
-		if (i == num_children - 1) {
-			// Make last child use remaining width of parent
-			child->width = parent->x + parent->width - child->x;
-		} else {
-			child->width = floor(child->width * scale);
-		}
-
-		child_x += child->width;
-
-		add_gaps(child);
-	}
-}
-
-static void apply_vert_layout(struct sway_container *parent) {
-	size_t num_children = parent->children->length;
-	if (!num_children) {
-		return;
-	}
-	size_t parent_offset = 0;
-	if (parent->parent->layout == L_TABBED) {
-		parent_offset = container_titlebar_height();
-	} else if (parent->parent->layout == L_STACKED) {
-		parent_offset =
-			container_titlebar_height() * parent->parent->children->length;
-	}
-	size_t parent_height = parent->height + parent_offset;
-
-	// Calculate total height of children
-	double total_height = 0;
-	for (size_t i = 0; i < num_children; ++i) {
-		struct sway_container *child = parent->children->items[i];
-
-		if (child->height <= 0) {
-			if (num_children > 1) {
-				child->height = parent_height / (num_children - 1);
-			} else {
-				child->height = parent_height;
-			}
-		}
-		remove_gaps(child);
-		total_height += child->height;
-	}
-	double scale = parent_height / total_height;
-
-	// Resize
-	wlr_log(L_DEBUG, "Arranging %p vertically", parent);
-	double child_y = parent->y + parent_offset;
-	struct sway_container *child;
-	for (size_t i = 0; i < num_children; ++i) {
-		child = parent->children->items[i];
-		wlr_log(L_DEBUG,
-				"Calculating arrangement for %p:%d (will scale %f by %f)",
-				child, child->type, child->height, scale);
-		child->x = parent->x;
-		child->y = child_y;
-		child->width = parent->width;
-
-		if (i == num_children - 1) {
-			// Make last child use remaining height of parent
-			child->height = parent->y + parent_offset + parent_height - child->y;
-		} else {
-			child->height = floor(child->height * scale);
-		}
-
-		child_y += child->height;
-
-		add_gaps(child);
-	}
-}
-
-static void apply_tabbed_or_stacked_layout(struct sway_container *parent) {
-	if (!parent->children->length) {
-		return;
-	}
-	size_t parent_offset = 0;
-	if (parent->parent->layout == L_TABBED) {
-		parent_offset = container_titlebar_height();
-	} else if (parent->parent->layout == L_STACKED) {
-		parent_offset =
-			container_titlebar_height() * parent->parent->children->length;
-	}
-	size_t parent_height = parent->height - parent_offset;
-	for (int i = 0; i < parent->children->length; ++i) {
-		struct sway_container *child = parent->children->items[i];
-		remove_gaps(child);
-		child->x = parent->x;
-		child->y = parent->y + parent_offset;
-		child->width = parent->width;
-		child->height = parent_height;
-		add_gaps(child);
-	}
-}
-
-void arrange_children_of(struct sway_container *parent) {
-	if (config->reloading) {
-		return;
-	}
-	if (!sway_assert(parent->type == C_WORKSPACE || parent->type == C_CONTAINER,
-			"container is a %s", container_type_to_str(parent->type))) {
-		return;
-	}
-
-	struct sway_container *workspace = parent;
-	if (workspace->type != C_WORKSPACE) {
-		workspace = container_parent(workspace, C_WORKSPACE);
-	}
-
-	if (workspace->sway_workspace->fullscreen) {
-		// Just arrange the fullscreen view and jump out
-		view_autoconfigure(workspace->sway_workspace->fullscreen);
-		return;
-	}
-
-	wlr_log(L_DEBUG, "Arranging layout for %p %s %fx%f+%f,%f", parent,
-		parent->name, parent->width, parent->height, parent->x, parent->y);
-
-	// Calculate x, y, width and height of children
-	switch (parent->layout) {
-	case L_HORIZ:
-		apply_horiz_layout(parent);
-		break;
-	case L_VERT:
-		apply_vert_layout(parent);
-		break;
-	case L_TABBED:
-	case L_STACKED:
-		apply_tabbed_or_stacked_layout(parent);
-		break;
-	default:
-		wlr_log(L_DEBUG, "TODO: arrange layout type %d", parent->layout);
-		apply_horiz_layout(parent);
-		break;
-	}
-
-	// Apply x, y, width and height to children and recurse if needed
-	for (int i = 0; i < parent->children->length; ++i) {
-		struct sway_container *child = parent->children->items[i];
-		if (parent->has_gaps && !child->has_gaps) {
-			child->has_gaps = true;
-			child->gaps_inner = parent->gaps_inner;
-			child->gaps_outer = parent->gaps_outer;
-		}
-		if (child->type == C_VIEW) {
-			view_autoconfigure(child->sway_view);
-		} else {
-			arrange_children_of(child);
-		}
-	}
-
-	// If container is a workspace, process floating containers too
-	if (parent->type == C_WORKSPACE) {
-		struct sway_workspace *ws = workspace->sway_workspace;
-		for (int i = 0; i < ws->floating->children->length; ++i) {
-			struct sway_container *child = ws->floating->children->items[i];
-			if (child->type != C_VIEW) {
-				arrange_children_of(child);
-			}
-		}
-	}
-
-	container_damage_whole(parent);
-	update_debug_tree();
-}

sway/tree/container.c

@@ -16,7 +16,6 @@
 #include "sway/ipc-server.h"
 #include "sway/output.h"
 #include "sway/server.h"
-#include "sway/tree/arrange.h"
 #include "sway/tree/layout.h"
 #include "sway/tree/view.h"
 #include "sway/tree/workspace.h"
@@ -113,9 +112,11 @@ struct sway_container *container_create(enum sway_container_type type) {
 	c->layout = L_NONE;
 	c->type = type;
 	c->alpha = 1.0f;
+	c->instructions = create_list();
 
 	if (type != C_VIEW) {
 		c->children = create_list();
+		c->current.children = create_list();
 	}
 
 	wl_signal_init(&c->events.destroy);
@@ -132,42 +133,67 @@ struct sway_container *container_create(enum sway_container_type type) {
 	return c;
 }
 
-static void _container_destroy(struct sway_container *cont) {
+static void container_workspace_free(struct sway_workspace *ws) {
-	if (cont == NULL) {
+	list_foreach(ws->output_priority, free);
+	list_free(ws->output_priority);
+	ws->floating->destroying = true;
+	container_free(ws->floating);
+	free(ws);
+}
+
+void container_free(struct sway_container *cont) {
+	if (!sway_assert(cont->destroying,
+				"Tried to free container which wasn't marked as destroying")) {
 		return;
 	}
-
+	if (!sway_assert(cont->instructions->length == 0,
-	wl_signal_emit(&cont->events.destroy, cont);
+				"Tried to free container with pending instructions")) {
-
+		return;
-	struct sway_container *parent = cont->parent;
-	if (cont->children != NULL && cont->children->length) {
-		// remove children until there are no more, container_destroy calls
-		// container_remove_child, which removes child from this container
-		while (cont->children != NULL && cont->children->length > 0) {
-			struct sway_container *child = cont->children->items[0];
-			ipc_event_window(child, "close");
-			container_remove_child(child);
-			_container_destroy(child);
-		}
 	}
-	if (cont->marks) {
+	free(cont->name);
-		list_foreach(cont->marks, free);
-		list_free(cont->marks);
-	}
-	if (parent) {
-		parent = container_remove_child(cont);
-	}
-	if (cont->name) {
-		free(cont->name);
-	}
-
 	wlr_texture_destroy(cont->title_focused);
 	wlr_texture_destroy(cont->title_focused_inactive);
 	wlr_texture_destroy(cont->title_unfocused);
 	wlr_texture_destroy(cont->title_urgent);
 
+	for (int i = 0; i < server.destroying_containers->length; ++i) {
+		if (server.destroying_containers->items[i] == cont) {
+			list_del(server.destroying_containers, i);
+			break;
+		}
+	}
+
+	list_free(cont->instructions);
 	list_free(cont->children);
-	cont->children = NULL;
+	list_free(cont->current.children);
+
+	switch (cont->type) {
+	case C_ROOT:
+		break;
+	case C_OUTPUT:
+		break;
+	case C_WORKSPACE:
+		container_workspace_free(cont->sway_workspace);
+		break;
+	case C_CONTAINER:
+		break;
+	case C_VIEW:
+		{
+			struct sway_view *view = cont->sway_view;
+			view->swayc = NULL;
+			free(view->title_format);
+			view->title_format = NULL;
+
+			if (view->destroying) {
+				view_free(view);
+			}
+		}
+		break;
+	case C_TYPES:
+		sway_assert(false, "Didn't expect to see C_TYPES here");
+		break;
+	}
+
 	free(cont);
 }
 
@@ -184,7 +210,6 @@ static struct sway_container *container_workspace_destroy(
 	}
 
 	wlr_log(L_DEBUG, "destroying workspace '%s'", workspace->name);
-	ipc_event_window(workspace, "close");
 
 	struct sway_container *parent = workspace->parent;
 	if (!workspace_is_empty(workspace) && output) {
@@ -209,24 +234,6 @@ static struct sway_container *container_workspace_destroy(
 		}
 	}
 
-	struct sway_workspace *sway_workspace = workspace->sway_workspace;
-
-	// This emits the destroy event and also destroys the swayc.
-	_container_destroy(workspace);
-
-	// Clean up the floating container
-	sway_workspace->floating->parent = NULL;
-	_container_destroy(sway_workspace->floating);
-
-	list_foreach(sway_workspace->output_priority, free);
-	list_free(sway_workspace->output_priority);
-
-	free(sway_workspace);
-
-	if (output) {
-		output_damage_whole(output->sway_output);
-	}
-
 	return parent;
 }
 
@@ -263,11 +270,10 @@ static struct sway_container *container_output_destroy(
 					container_add_child(new_output, workspace);
 					ipc_event_workspace(workspace, NULL, "move");
 				} else {
-					container_workspace_destroy(workspace);
+					container_destroy(workspace);
 				}
 
 				container_sort_workspaces(new_output);
-				arrange_output(new_output);
 			}
 		}
 	}
@@ -280,14 +286,48 @@ static struct sway_container *container_output_destroy(
 	wl_list_remove(&output->sway_output->damage_frame.link);
 
 	output->sway_output->swayc = NULL;
+	output->sway_output = NULL;
 
 	wlr_log(L_DEBUG, "OUTPUT: Destroying output '%s'", output->name);
-	_container_destroy(output);
+
 	return &root_container;
 }
 
-static void container_root_finish(struct sway_container *con) {
+/**
-	wlr_log(L_ERROR, "TODO: destroy the root container");
+ * Implement the actual destroy logic, without reaping.
+ */
+static struct sway_container *container_destroy_noreaping(
+		struct sway_container *con) {
+	if (con == NULL) {
+		return NULL;
+	}
+	if (con->destroying) {
+		return NULL;
+	}
+
+	wl_signal_emit(&con->events.destroy, con);
+	ipc_event_window(con, "close");
+
+	// The below functions move their children to somewhere else.
+	if (con->type == C_OUTPUT) {
+		container_output_destroy(con);
+	} else if (con->type == C_WORKSPACE) {
+		// Workspaces will refuse to be destroyed if they're the last workspace
+		// on their output.
+		if (!container_workspace_destroy(con)) {
+			wlr_log(L_ERROR, "workspace doesn't want to destroy");
+			return NULL;
+		}
+	}
+
+	con->destroying = true;
+	list_add(server.destroying_containers, con);
+
+	if (!con->parent) {
+		return NULL;
+	}
+
+	return container_remove_child(con);
 }
 
 bool container_reap_empty(struct sway_container *con) {
@@ -303,13 +343,13 @@ bool container_reap_empty(struct sway_container *con) {
 	case C_WORKSPACE:
 		if (!workspace_is_visible(con) && workspace_is_empty(con)) {
 			wlr_log(L_DEBUG, "Destroying workspace via reaper");
-			container_workspace_destroy(con);
+			container_destroy_noreaping(con);
 			return true;
 		}
 		break;
 	case C_CONTAINER:
 		if (con->children->length == 0) {
-			_container_destroy(con);
+			container_destroy_noreaping(con);
 			return true;
 		}
 	case C_VIEW:
@@ -340,52 +380,27 @@ struct sway_container *container_flatten(struct sway_container *container) {
 		struct sway_container *child = container->children->items[0];
 		struct sway_container *parent = container->parent;
 		container_replace_child(container, child);
-		container_destroy(container);
+		container_destroy_noreaping(container);
 		container = parent;
 	}
 	return container;
 }
 
+/**
+ * container_destroy() is the first step in destroying a container. We'll emit
+ * events, detach it from the tree and mark it as destroying. The container will
+ * remain in memory until it's no longer used by a transaction, then it will be
+ * freed via container_free().
+ *
+ * This function just wraps container_destroy_noreaping(), then does reaping.
+ */
 struct sway_container *container_destroy(struct sway_container *con) {
-	if (con == NULL) {
+	struct sway_container *parent = container_destroy_noreaping(con);
+
+	if (!parent) {
 		return NULL;
 	}
 
-	struct sway_container *parent = con->parent;
-
-	switch (con->type) {
-		case C_ROOT:
-			container_root_finish(con);
-			break;
-		case C_OUTPUT:
-			// dont try to reap the root after this
-			container_output_destroy(con);
-			break;
-		case C_WORKSPACE:
-			// dont try to reap the output after this
-			container_workspace_destroy(con);
-			break;
-		case C_CONTAINER:
-			if (con->children->length) {
-				for (int i = 0; i < con->children->length; ++i) {
-					struct sway_container *child = con->children->items[0];
-					ipc_event_window(child, "close");
-					container_remove_child(child);
-					container_add_child(parent, child);
-				}
-			}
-			ipc_event_window(con, "close");
-			_container_destroy(con);
-			break;
-		case C_VIEW:
-			_container_destroy(con);
-			break;
-		case C_TYPES:
-			wlr_log(L_ERROR, "container_destroy called on an invalid "
-				"container");
-			break;
-	}
-
 	return container_reap_empty_recursive(parent);
 }
 
@@ -753,9 +768,6 @@ static void update_title_texture(struct sway_container *con,
 			"Unexpected type %s", container_type_to_str(con->type))) {
 		return;
 	}
-	if (!con->width) {
-		return;
-	}
 	struct sway_container *output = container_parent(con, C_OUTPUT);
 	if (!output) {
 		return;
@@ -917,13 +929,12 @@ void container_set_floating(struct sway_container *container, bool enable) {
 
 	struct sway_container *workspace = container_parent(container, C_WORKSPACE);
 	struct sway_seat *seat = input_manager_current_seat(input_manager);
-	container_damage_whole(container);
 
 	if (enable) {
 		container_remove_child(container);
 		container_add_child(workspace->sway_workspace->floating, container);
 		if (container->type == C_VIEW) {
-			view_autoconfigure(container->sway_view);
+			view_init_floating(container->sway_view);
 		}
 		seat_set_focus(seat, seat_get_focus_inactive(seat, container));
 		container_reap_empty_recursive(workspace);
@@ -939,8 +950,8 @@ void container_set_floating(struct sway_container *container, bool enable) {
 		container->is_sticky = false;
 		container_reap_empty_recursive(workspace->sway_workspace->floating);
 	}
-	arrange_workspace(workspace);
+
-	container_damage_whole(container);
+	ipc_event_window(container, "floating");
 }
 
 void container_set_geometry_from_floating_view(struct sway_container *con) {
@@ -969,3 +980,10 @@ bool container_is_floating(struct sway_container *container) {
 	}
 	return container->parent == workspace->sway_workspace->floating;
 }
+
+void container_get_box(struct sway_container *container, struct wlr_box *box) {
+	box->x = container->x;
+	box->y = container->y;
+	box->width = container->width;
+	box->height = container->height;
+}

sway/tree/layout.c

@@ -22,7 +22,7 @@ struct sway_container root_container;
 
 static void output_layout_handle_change(struct wl_listener *listener,
 		void *data) {
-	arrange_root();
+	arrange_and_commit(&root_container);
 }
 
 void layout_init(void) {
@@ -30,7 +30,9 @@ void layout_init(void) {
 	root_container.type = C_ROOT;
 	root_container.layout = L_NONE;
 	root_container.name = strdup("root");
+	root_container.instructions = create_list();
 	root_container.children = create_list();
+	root_container.current.children = create_list();
 	wl_signal_init(&root_container.events.destroy);
 
 	root_container.sway_root = calloc(1, sizeof(*root_container.sway_root));
@@ -57,18 +59,17 @@ static int index_child(const struct sway_container *child) {
 	return -1;
 }
 
-static void container_handle_fullscreen_reparent(struct sway_container *viewcon,
+static void container_handle_fullscreen_reparent(struct sway_container *con,
 		struct sway_container *old_parent) {
-	if (viewcon->type != C_VIEW || !viewcon->sway_view->is_fullscreen) {
+	if (con->type != C_VIEW || !con->sway_view->is_fullscreen) {
 		return;
 	}
-	struct sway_view *view = viewcon->sway_view;
+	struct sway_view *view = con->sway_view;
 	struct sway_container *old_workspace = old_parent;
 	if (old_workspace && old_workspace->type != C_WORKSPACE) {
 		old_workspace = container_parent(old_workspace, C_WORKSPACE);
 	}
-	struct sway_container *new_workspace = container_parent(view->swayc,
+	struct sway_container *new_workspace = container_parent(con, C_WORKSPACE);
-			C_WORKSPACE);
 	if (old_workspace == new_workspace) {
 		return;
 	}
@@ -79,15 +80,19 @@ static void container_handle_fullscreen_reparent(struct sway_container *viewcon,
 
 	// Mark the new workspace as fullscreen
 	if (new_workspace->sway_workspace->fullscreen) {
-		view_set_fullscreen_raw(
+		view_set_fullscreen(new_workspace->sway_workspace->fullscreen, false);
-				new_workspace->sway_workspace->fullscreen, false);
 	}
 	new_workspace->sway_workspace->fullscreen = view;
 	// Resize view to new output dimensions
 	struct sway_container *output = new_workspace->parent;
-	view_configure(view, 0, 0, output->width, output->height);
+	view->x = output->x;
-	view->swayc->width = output->width;
+	view->y = output->y;
-	view->swayc->height = output->height;
+	view->width = output->width;
+	view->height = output->height;
+	con->x = output->x;
+	con->y = output->y;
+	con->width = output->width;
+	con->height = output->height;
 }
 
 void container_insert_child(struct sway_container *parent,
@@ -189,18 +194,7 @@ void container_move_to(struct sway_container *container,
 	}
 	container_notify_subtree_changed(old_parent);
 	container_notify_subtree_changed(new_parent);
-	if (old_parent) {
+
-		if (old_parent->type == C_OUTPUT) {
-			arrange_output(old_parent);
-		} else {
-			arrange_children_of(old_parent);
-		}
-	}
-	if (new_parent->type == C_OUTPUT) {
-		arrange_output(new_parent);
-	} else {
-		arrange_children_of(new_parent);
-	}
 	// If view was moved to a fullscreen workspace, refocus the fullscreen view
 	struct sway_container *new_workspace = container;
 	if (new_workspace->type != C_WORKSPACE) {
@@ -215,7 +209,8 @@ void container_move_to(struct sway_container *container,
 			if (focus_ws->type != C_WORKSPACE) {
 				focus_ws = container_parent(focus_ws, C_WORKSPACE);
 			}
-			seat_set_focus(seat, new_workspace->sway_workspace->fullscreen->swayc);
+			seat_set_focus(seat,
+					new_workspace->sway_workspace->fullscreen->swayc);
 			if (focus_ws != new_workspace) {
 				seat_set_focus(seat, focus);
 			}
@@ -309,7 +304,6 @@ static void workspace_rejigger(struct sway_container *ws,
 	container_reap_empty_recursive(original_parent);
 	wl_signal_emit(&child->events.reparent, original_parent);
 	container_create_notify(new_parent);
-	arrange_workspace(ws);
 }
 
 static void move_out_of_tabs_stacks(struct sway_container *container,
@@ -320,11 +314,6 @@ static void move_out_of_tabs_stacks(struct sway_container *container,
 		wlr_log(L_DEBUG, "Changing layout of %zd", current->parent->id);
 		current->parent->layout = move_dir ==
 			MOVE_LEFT || move_dir == MOVE_RIGHT ? L_HORIZ : L_VERT;
-		if (current->parent->type == C_WORKSPACE) {
-			arrange_workspace(current->parent);
-		} else {
-			arrange_children_of(current->parent);
-		}
 		return;
 	}
 
@@ -340,11 +329,6 @@ static void move_out_of_tabs_stacks(struct sway_container *container,
 		container_flatten(new_parent->parent);
 	}
 	container_create_notify(new_parent);
-	if (is_workspace) {
-		arrange_workspace(new_parent->parent);
-	} else {
-		arrange_children_of(new_parent);
-	}
 	container_notify_subtree_changed(new_parent);
 }
 
@@ -368,10 +352,7 @@ void container_move(struct sway_container *container,
 
 	struct sway_container *new_parent = container_flatten(parent);
 	if (new_parent != parent) {
-		// Special case: we were the last one in this container, so flatten it
+		// Special case: we were the last one in this container, so leave
-		// and leave
-		arrange_children_of(new_parent);
-		update_debug_tree();
 		return;
 	}
 
@@ -453,12 +434,9 @@ void container_move(struct sway_container *container,
 						wlr_log(L_DEBUG, "Hit limit, "
 								"promoting descendant to sibling");
 						// Special case
-						struct sway_container *old_parent = container->parent;
 						container_insert_child(current->parent, container,
 								index + (offs < 0 ? 0 : 1));
 						container->width = container->height = 0;
-						arrange_children_of(current->parent);
-						arrange_children_of(old_parent);
 						return;
 					}
 				} else {
@@ -492,14 +470,11 @@ void container_move(struct sway_container *container,
 				wlr_log(L_DEBUG, "Swapping siblings");
 				sibling->parent->children->items[index + offs] = container;
 				sibling->parent->children->items[index] = sibling;
-				arrange_children_of(sibling->parent);
 			} else {
 				wlr_log(L_DEBUG, "Promoting to sibling of cousin");
 				container_insert_child(sibling->parent, container,
 						index_child(sibling) + (offs > 0 ? 0 : 1));
 				container->width = container->height = 0;
-				arrange_children_of(sibling->parent);
-				arrange_children_of(old_parent);
 			}
 			sibling = NULL;
 			break;
@@ -513,8 +488,6 @@ void container_move(struct sway_container *container,
 						"(move dir: %d)", limit, move_dir);
 				container_insert_child(sibling, container, limit);
 				container->width = container->height = 0;
-				arrange_children_of(sibling);
-				arrange_children_of(old_parent);
 				sibling = NULL;
 			} else {
 				wlr_log(L_DEBUG, "Reparenting container (perpendicular)");
@@ -538,8 +511,6 @@ void container_move(struct sway_container *container,
 					container_add_child(sibling, container);
 				}
 				container->width = container->height = 0;
-				arrange_children_of(sibling);
-				arrange_children_of(old_parent);
 				sibling = NULL;
 			}
 			break;
@@ -864,7 +835,6 @@ struct sway_container *container_split(struct sway_container *child,
 		// Special case: this just behaves like splitt
 		child->prev_layout = child->layout;
 		child->layout = layout;
-		arrange_children_of(child);
 		return child;
 	}
 
@@ -882,7 +852,7 @@ struct sway_container *container_split(struct sway_container *child,
 
 	struct sway_seat *seat = input_manager_get_default_seat(input_manager);
 	bool set_focus = (seat_get_focus(seat) == child);
-	
+
 	add_gaps(cont);
 
 	if (child->type == C_WORKSPACE) {
@@ -912,7 +882,6 @@ struct sway_container *container_split(struct sway_container *child,
 	}
 
 	container_notify_subtree_changed(cont);
-	arrange_children_of(cont);
 	return cont;
 }
 
@@ -1050,9 +1019,6 @@ void container_swap(struct sway_container *con1, struct sway_container *con2) {
 		prev_workspace_name = stored_prev_name;
 	}
 
-	arrange_children_of(con1->parent);
-	arrange_children_of(con2->parent);
-
 	if (fs1 && con2->type == C_VIEW) {
 		view_set_fullscreen(con2->sway_view, true);
 	}

sway/tree/output.c

@@ -26,12 +26,9 @@ static void restore_workspaces(struct sway_container *output) {
 				j--;
 			}
 		}
-
-		arrange_output(other);
 	}
 
 	container_sort_workspaces(output);
-	arrange_output(output);
 }
 
 struct sway_container *output_create(

sway/tree/view.c

@@ -28,20 +28,22 @@ void view_init(struct sway_view *view, enum sway_view_type type,
 	wl_signal_init(&view->events.unmap);
 }
 
-void view_destroy(struct sway_view *view) {
+void view_free(struct sway_view *view) {
-	if (view == NULL) {
+	if (!sway_assert(view->surface == NULL, "Tried to free mapped view")) {
 		return;
 	}
-
+	if (!sway_assert(view->destroying,
-	if (view->surface != NULL) {
+				"Tried to free view which wasn't marked as destroying")) {
-		view_unmap(view);
+		return;
+	}
+	if (!sway_assert(view->swayc == NULL,
+				"Tried to free view which still has a swayc "
+				"(might have a pending transaction?)")) {
+		return;
 	}
-
 	list_free(view->executed_criteria);
 
-	for (int i = 0; i < view->marks->length; ++i) {
+	list_foreach(view->marks, free);
-		free(view->marks->items[i]);
-	}
 	list_free(view->marks);
 
 	wlr_texture_destroy(view->marks_focused);
@@ -49,8 +51,6 @@ void view_destroy(struct sway_view *view) {
 	wlr_texture_destroy(view->marks_unfocused);
 	wlr_texture_destroy(view->marks_urgent);
 
-	container_destroy(view->swayc);
-
 	if (view->impl->destroy) {
 		view->impl->destroy(view);
 	} else {
@@ -58,6 +58,27 @@ void view_destroy(struct sway_view *view) {
 	}
 }
 
+/**
+ * The view may or may not be involved in a transaction. For example, a view may
+ * unmap then attempt to destroy itself before we've applied the new layout. If
+ * an unmapping view is still involved in a transaction then it'll still have a
+ * swayc.
+ *
+ * If there's no transaction we can simply free the view. Otherwise the
+ * destroying flag will make the view get freed when the transaction is
+ * finished.
+ */
+void view_destroy(struct sway_view *view) {
+	if (!sway_assert(view->surface == NULL, "Tried to destroy a mapped view")) {
+		return;
+	}
+	view->destroying = true;
+
+	if (!view->swayc) {
+		view_free(view);
+	}
+}
+
 const char *view_get_title(struct sway_view *view) {
 	if (view->impl->get_string_prop) {
 		return view->impl->get_string_prop(view, VIEW_PROP_TITLE);
@@ -119,32 +140,33 @@ const char *view_get_shell(struct sway_view *view) {
 	return "unknown";
 }
 
-void view_configure(struct sway_view *view, double lx, double ly, int width,
+uint32_t view_configure(struct sway_view *view, double lx, double ly, int width,
 		int height) {
 	if (view->impl->configure) {
-		view->impl->configure(view, lx, ly, width, height);
+		return view->impl->configure(view, lx, ly, width, height);
 	}
+	return 0;
 }
 
-static void view_autoconfigure_floating(struct sway_view *view) {
+void view_init_floating(struct sway_view *view) {
 	struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
 	int max_width = ws->width * 0.6666;
 	int max_height = ws->height * 0.6666;
-	int width =
+	view->width =
 		view->natural_width > max_width ? max_width : view->natural_width;
-	int height =
+	view->height =
 		view->natural_height > max_height ? max_height : view->natural_height;
-	int lx = ws->x + (ws->width - width) / 2;
+	view->x = ws->x + (ws->width - view->width) / 2;
-	int ly = ws->y + (ws->height - height) / 2;
+	view->y = ws->y + (ws->height - view->height) / 2;
 
 	// If the view's border is B_NONE then these properties are ignored.
 	view->border_top = view->border_bottom = true;
 	view->border_left = view->border_right = true;
 
+	container_set_geometry_from_floating_view(view->swayc);
+
 	// Don't maximize floating windows
 	view_set_tiled(view, false);
-
-	view_configure(view, lx, ly, width, height);
 }
 
 void view_autoconfigure(struct sway_view *view) {
@@ -156,12 +178,14 @@ void view_autoconfigure(struct sway_view *view) {
 	struct sway_container *output = container_parent(view->swayc, C_OUTPUT);
 
 	if (view->is_fullscreen) {
-		view_configure(view, output->x, output->y, output->width, output->height);
+		view->x = output->x;
+		view->y = output->y;
+		view->width = output->width;
+		view->height = output->height;
 		return;
 	}
 
 	if (container_is_floating(view->swayc)) {
-		view_autoconfigure_floating(view);
 		return;
 	}
 
@@ -181,20 +205,22 @@ void view_autoconfigure(struct sway_view *view) {
 		}
 	}
 
+	struct sway_container *con = view->swayc;
+
 	view->border_top = view->border_bottom = true;
 	view->border_left = view->border_right = true;
 	if (config->hide_edge_borders == E_BOTH
 			|| config->hide_edge_borders == E_VERTICAL
 			|| (config->hide_edge_borders == E_SMART && !other_views)) {
-		view->border_left = view->swayc->x != ws->x;
+		view->border_left = con->x != ws->x;
-		int right_x = view->swayc->x + view->swayc->width;
+		int right_x = con->x + con->width;
 		view->border_right = right_x != ws->x + ws->width;
 	}
 	if (config->hide_edge_borders == E_BOTH
 			|| config->hide_edge_borders == E_HORIZONTAL
 			|| (config->hide_edge_borders == E_SMART && !other_views)) {
-		view->border_top = view->swayc->y != ws->y;
+		view->border_top = con->y != ws->y;
-		int bottom_y = view->swayc->y + view->swayc->height;
+		int bottom_y = con->y + con->height;
 		view->border_bottom = bottom_y != ws->y + ws->height;
 	}
 
@@ -205,45 +231,44 @@ void view_autoconfigure(struct sway_view *view) {
 	// In a tabbed or stacked container, the swayc's y is the top of the title
 	// area. We have to offset the surface y by the height of the title bar, and
 	// disable any top border because we'll always have the title bar.
-	if (view->swayc->parent->layout == L_TABBED) {
+	if (con->parent->layout == L_TABBED) {
 		y_offset = container_titlebar_height();
 		view->border_top = false;
-	} else if (view->swayc->parent->layout == L_STACKED) {
+	} else if (con->parent->layout == L_STACKED) {
-		y_offset = container_titlebar_height()
+		y_offset = container_titlebar_height() * con->parent->children->length;
-			* view->swayc->parent->children->length;
 		view->border_top = false;
 	}
 
 	switch (view->border) {
 	case B_NONE:
-		x = view->swayc->x;
+		x = con->x;
-		y = view->swayc->y + y_offset;
+		y = con->y + y_offset;
-		width = view->swayc->width;
+		width = con->width;
-		height = view->swayc->height - y_offset;
+		height = con->height - y_offset;
 		break;
 	case B_PIXEL:
-		x = view->swayc->x + view->border_thickness * view->border_left;
+		x = con->x + view->border_thickness * view->border_left;
-		y = view->swayc->y + view->border_thickness * view->border_top + y_offset;
+		y = con->y + view->border_thickness * view->border_top + y_offset;
-		width = view->swayc->width
+		width = con->width
 			- view->border_thickness * view->border_left
 			- view->border_thickness * view->border_right;
-		height = view->swayc->height - y_offset
+		height = con->height - y_offset
 			- view->border_thickness * view->border_top
 			- view->border_thickness * view->border_bottom;
 		break;
 	case B_NORMAL:
 		// Height is: 1px border + 3px pad + title height + 3px pad + 1px border
-		x = view->swayc->x + view->border_thickness * view->border_left;
+		x = con->x + view->border_thickness * view->border_left;
-		width = view->swayc->width
+		width = con->width
 			- view->border_thickness * view->border_left
 			- view->border_thickness * view->border_right;
 		if (y_offset) {
-			y = view->swayc->y + y_offset;
+			y = con->y + y_offset;
-			height = view->swayc->height - y_offset
+			height = con->height - y_offset
 				- view->border_thickness * view->border_bottom;
 		} else {
-			y = view->swayc->y + container_titlebar_height();
+			y = con->y + container_titlebar_height();
-			height = view->swayc->height - container_titlebar_height()
+			height = con->height - container_titlebar_height()
 				- view->border_thickness * view->border_bottom;
 		}
 		break;
@@ -251,8 +276,9 @@ void view_autoconfigure(struct sway_view *view) {
 
 	view->x = x;
 	view->y = y;
+	view->width = width;
+	view->height = height;
 	view_set_tiled(view, true);
-	view_configure(view, x, y, width, height);
 }
 
 void view_set_activated(struct sway_view *view, bool activated) {
@@ -268,8 +294,7 @@ void view_set_tiled(struct sway_view *view, bool tiled) {
 	}
 }
 
-// Set fullscreen, but without IPC events or arranging windows.
+void view_set_fullscreen(struct sway_view *view, bool fullscreen) {
-void view_set_fullscreen_raw(struct sway_view *view, bool fullscreen) {
 	if (view->is_fullscreen == fullscreen) {
 		return;
 	}
@@ -315,27 +340,17 @@ void view_set_fullscreen_raw(struct sway_view *view, bool fullscreen) {
 	} else {
 		workspace->sway_workspace->fullscreen = NULL;
 		if (container_is_floating(view->swayc)) {
-			view_configure(view, view->saved_x, view->saved_y,
+			view->x = view->saved_x;
-					view->saved_width, view->saved_height);
+			view->y = view->saved_y;
+			view->width = view->saved_width;
+			view->height = view->saved_height;
+			container_set_geometry_from_floating_view(view->swayc);
 		} else {
 			view->swayc->width = view->swayc->saved_width;
 			view->swayc->height = view->swayc->saved_height;
-			view_autoconfigure(view);
 		}
 	}
-}
 
-void view_set_fullscreen(struct sway_view *view, bool fullscreen) {
-	if (view->is_fullscreen == fullscreen) {
-		return;
-	}
-
-	view_set_fullscreen_raw(view, fullscreen);
-
-	struct sway_container *workspace =
-		container_parent(view->swayc, C_WORKSPACE);
-	arrange_workspace(workspace);
-	output_damage_whole(workspace->parent->sway_output);
 	ipc_event_window(view->swayc, "fullscreen_mode");
 }
 
@@ -365,6 +380,9 @@ static void view_get_layout_box(struct sway_view *view, struct wlr_box *box) {
 
 void view_for_each_surface(struct sway_view *view,
 		wlr_surface_iterator_func_t iterator, void *user_data) {
+	if (!view->surface) {
+		return;
+	}
 	if (view->impl->for_each_surface) {
 		view->impl->for_each_surface(view, iterator, user_data);
 	} else {
@@ -518,8 +536,6 @@ void view_map(struct sway_view *view, struct wlr_surface *wlr_surface) {
 
 	if (view->impl->wants_floating && view->impl->wants_floating(view)) {
 		container_set_floating(view->swayc, true);
-	} else {
-		arrange_children_of(cont->parent);
 	}
 
 	input_manager_set_focus(input_manager, cont);
@@ -531,42 +547,26 @@ void view_map(struct sway_view *view, struct wlr_surface *wlr_surface) {
 	container_notify_subtree_changed(view->swayc->parent);
 	view_execute_criteria(view);
 
-	container_damage_whole(cont);
 	view_handle_container_reparent(&view->container_reparent, NULL);
 }
 
 void view_unmap(struct sway_view *view) {
-	if (!sway_assert(view->surface != NULL, "cannot unmap unmapped view")) {
-		return;
-	}
-
 	wl_signal_emit(&view->events.unmap, view);
 
-	if (view->is_fullscreen) {
-		struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
-		ws->sway_workspace->fullscreen = NULL;
-	}
-
-	container_damage_whole(view->swayc);
-
 	wl_list_remove(&view->surface_new_subsurface.link);
 	wl_list_remove(&view->container_reparent.link);
 
-	struct sway_container *parent = container_destroy(view->swayc);
+	if (view->is_fullscreen) {
+		struct sway_container *ws = container_parent(view->swayc, C_WORKSPACE);
+		ws->sway_workspace->fullscreen = NULL;
+		container_destroy(view->swayc);
 
-	view->swayc = NULL;
+		arrange_and_commit(ws->parent);
-	view->surface = NULL;
-
-	if (view->title_format) {
-		free(view->title_format);
-		view->title_format = NULL;
-	}
-
-	if (parent->type == C_OUTPUT) {
-		arrange_output(parent);
 	} else {
-		arrange_children_of(parent);
+		struct sway_container *parent = container_destroy(view->swayc);
+		arrange_and_commit(parent);
 	}
+	view->surface = NULL;
 }
 
 void view_update_position(struct sway_view *view, double lx, double ly) {
@@ -940,7 +940,7 @@ void view_update_marks_textures(struct sway_view *view) {
 }
 
 bool view_is_visible(struct sway_view *view) {
-	if (!view->swayc) {
+	if (!view->swayc || view->swayc->destroying) {
 		return false;
 	}
 	struct sway_container *workspace =

sway/tree/workspace.c

@@ -425,11 +425,14 @@ bool workspace_switch(struct sway_container *workspace) {
 	}
 	seat_set_focus(seat, next);
 	struct sway_container *output = container_parent(workspace, C_OUTPUT);
-	arrange_output(output);
+	arrange_and_commit(output);
 	return true;
 }
 
 bool workspace_is_visible(struct sway_container *ws) {
+	if (ws->destroying) {
+		return false;
+	}
 	struct sway_container *output = container_parent(ws, C_OUTPUT);
 	struct sway_seat *seat = input_manager_current_seat(input_manager);
 	struct sway_container *focus = seat_get_focus_inactive(seat, output);