WIP: Atomic layout updates ground work

include/sway/desktop/transaction.h

@@ -0,0 +1,56 @@
+#ifndef _SWAY_TRANSACTION_H
+#define _SWAY_TRANSACTION_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 {
+	struct wl_event_source *timer;
+	list_t *instructions;   // struct sway_transaction_instruction *
+	list_t *damage;         // struct wlr_box *
+	size_t num_waiting;
+};
+
+/**
+ * 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);
+
+/**
+ * Add a box to be damaged when the transaction is applied.
+ * The box should be in layout coordinates.
+ */
+void transaction_add_damage(struct sway_transaction *transaction,
+		struct wlr_box *box);
+
+/**
+ * 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);
+
+#endif

include/sway/output.h

@@ -40,6 +40,8 @@ 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/tree/arrange.h

@@ -1,18 +1,33 @@
 #ifndef _SWAY_ARRANGE_H
 #define _SWAY_ARRANGE_H
+#include "sway/desktop/transaction.h"
 
 struct sway_container;
 
-// Determine the root container's geometry, then iterate to everything below
-void arrange_root(void);
-
-// Determine the output's geometry, then iterate to everything below
-void arrange_output(struct sway_container *output);
+/**
+ * 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.
+ */
+void arrange_windows(struct sway_container *container,
+		struct sway_transaction *transaction);
 
-// Determine the workspace's geometry, then iterate to everything below
-void arrange_workspace(struct sway_container *workspace);
+/**
+ * Arrange layout for the given container and commit the transaction.
+ *
+ * This function is a wrapper around arrange_windows, and handles creating and
+ * committing the transaction for you. Use this function if you're only doing
+ * one arrange operation.
+ */
+void arrange_and_commit(struct sway_container *container);
 
-// Arrange layout for all the children of the given workspace/container
-void arrange_children_of(struct sway_container *parent);
+// These functions are temporary and are only here to make everything compile.
+// They are wrappers around arrange_and_commit.
+void arrange_root(void);
+void arrange_output(struct sway_container *container);
+void arrange_workspace(struct sway_container *container);
+void arrange_children_of(struct sway_container *container);
 
 #endif

include/sway/tree/container.h

@@ -54,6 +54,28 @@ 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;
+
+	//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;
+};
+
 struct sway_container {
 	union {
 		// TODO: Encapsulate state for other node types as well like C_CONTAINER
@@ -69,6 +91,8 @@ struct sway_container {
 	 */
 	size_t id;
 
+	struct sway_container_state pending;
+
 	char *name;            // The view's title (unformatted)
 	char *formatted_title; // The title displayed in the title bar
 
@@ -246,4 +270,9 @@ 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.
+ */
+struct wlr_box *container_get_box(struct sway_container *container);
+
 #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,
-		int height);
+	uint32_t (*configure)(struct sway_view *view, double lx, double ly,
+			int width, int height);
 	void (*set_activated)(struct sway_view *view, bool activated);
 	void (*set_fullscreen)(struct sway_view *view, bool fullscreen);
 	bool (*wants_floating)(struct sway_view *view);
@@ -70,6 +70,12 @@ struct sway_view {
 
 	list_t *executed_criteria; // struct criteria *
 	list_t *marks;             // char *
+	list_t *instructions;      // struct sway_transaction_instruction *
+
+	// If saved_texture is set, the main surface of the view will render this
+	// texture instead of its own. This is used while waiting for transactions
+	// to complete.
+	struct wlr_texture *saved_texture;
 
 	struct wlr_texture *marks_focused;
 	struct wlr_texture *marks_focused_inactive;
@@ -103,8 +109,6 @@ 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 {
@@ -119,8 +123,6 @@ 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 {
@@ -138,9 +140,6 @@ 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 {
@@ -212,7 +211,7 @@ 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);
 
 /**

sway/desktop/output.c

@@ -69,6 +69,7 @@ struct render_data {
 	struct root_geometry root_geo;
 	struct sway_output *output;
 	pixman_region32_t *damage;
+	struct sway_view *view;
 	float alpha;
 };
 
@@ -108,6 +109,38 @@ static bool get_surface_box(struct root_geometry *geo,
 	return wlr_box_intersection(&output_box, &rotated_box, &intersection);
 }
 
+static bool get_view_box(struct root_geometry *geo,
+		struct sway_output *output, struct sway_view *view, int sx, int sy,
+		struct wlr_box *surface_box) {
+	int sw = view->width;
+	int sh = view->height;
+
+	double _sx = sx, _sy = sy;
+	rotate_child_position(&_sx, &_sy, sw, sh, geo->width, geo->height,
+		geo->rotation);
+
+	struct wlr_box box = {
+		.x = geo->x + _sx,
+		.y = geo->y + _sy,
+		.width = sw,
+		.height = sh,
+	};
+	if (surface_box != NULL) {
+		memcpy(surface_box, &box, sizeof(struct wlr_box));
+	}
+
+	struct wlr_box rotated_box;
+	wlr_box_rotated_bounds(&box, geo->rotation, &rotated_box);
+
+	struct wlr_box output_box = {
+		.width = output->swayc->width,
+		.height = output->swayc->height,
+	};
+
+	struct wlr_box intersection;
+	return wlr_box_intersection(&output_box, &rotated_box, &intersection);
+}
+
 static void surface_for_each_surface(struct wlr_surface *surface,
 		double ox, double oy, struct root_geometry *geo,
 		wlr_surface_iterator_func_t iterator, void *user_data) {
@@ -225,13 +258,26 @@ static void render_surface_iterator(struct wlr_surface *surface, int sx, int sy,
 	pixman_region32_t *output_damage = data->damage;
 	float alpha = data->alpha;
 
-	if (!wlr_surface_has_buffer(surface)) {
-		return;
+	struct wlr_texture *texture = NULL;
+	struct wlr_box box;
+	bool intersects;
+
+	// If this is the main surface of a view, render the saved_texture instead
+	// if it exists. It exists when we are mid-transaction.
+	if (data->view && data->view->saved_texture &&
+			data->view->surface == surface) {
+		texture = data->view->saved_texture;
+		intersects = get_view_box(&data->root_geo, data->output, data->view,
+				sx, sy, &box);
+	} else {
+		if (!wlr_surface_has_buffer(surface)) {
+			return;
+		}
+		texture = surface->texture;
+		intersects = get_surface_box(&data->root_geo, data->output, surface,
+				sx, sy, &box);
 	}
 
-	struct wlr_box box;
-	bool intersects = get_surface_box(&data->root_geo, data->output, surface,
-		sx, sy, &box);
 	if (!intersects) {
 		return;
 	}
@@ -244,8 +290,7 @@ static void render_surface_iterator(struct wlr_surface *surface, int sx, int sy,
 	wlr_matrix_project_box(matrix, &box, transform, rotation,
 		wlr_output->transform_matrix);
 
-	render_texture(wlr_output, output_damage, surface->texture, &box, matrix,
-		alpha);
+	render_texture(wlr_output, output_damage, texture, &box, matrix, alpha);
 }
 
 static void render_layer(struct sway_output *output,
@@ -315,6 +360,7 @@ 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(
@@ -1105,6 +1151,16 @@ 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->x;
+	box.y -= output->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;