text: #define _POSIX_C_SOURCE 200809L
  #include <assert.h>
  #include <stdlib.h>
  #include <strings.h>
  #include <time.h>
  #include <wayland-server-core.h>
  #include <wlr/backend/drm.h>
  #include <wlr/render/wlr_renderer.h>
  #include <wlr/types/wlr_buffer.h>
  #include <wlr/types/wlr_drm_lease_v1.h>
  #include <wlr/types/wlr_matrix.h>
  #include <wlr/types/wlr_output_damage.h>
  #include <wlr/types/wlr_output_layout.h>
  #include <wlr/types/wlr_output.h>
  #include <wlr/types/wlr_presentation_time.h>
  #include <wlr/types/wlr_surface.h>
  #include <wlr/util/region.h>
  #include "config.h"
  #include "log.h"
  #include "sway/config.h"
  #include "sway/desktop/transaction.h"
  #include "sway/input/input-manager.h"
  #include "sway/input/seat.h"
  #include "sway/layers.h"
  #include "sway/output.h"
  #include "sway/server.h"
  #include "sway/surface.h"
  #include "sway/tree/arrange.h"
  #include "sway/tree/container.h"
  #include "sway/tree/root.h"
  #include "sway/tree/view.h"
  #include "sway/tree/workspace.h"
  
  struct sway_output *output_by_name_or_id(const char *name_or_id) {
  	for (int i = 0; i < root->outputs->length; ++i) {
  		struct sway_output *output = root->outputs->items[i];
  		char identifier[128];
  		output_get_identifier(identifier, sizeof(identifier), output);
  		if (strcasecmp(identifier, name_or_id) == 0
  				|| strcasecmp(output->wlr_output->name, name_or_id) == 0) {
  			return output;
  		}
  	}
  	return NULL;
  }
  
  struct sway_output *all_output_by_name_or_id(const char *name_or_id) {
  	struct sway_output *output;
  	wl_list_for_each(output, &root->all_outputs, link) {
  		char identifier[128];
  		output_get_identifier(identifier, sizeof(identifier), output);
  		if (strcasecmp(identifier, name_or_id) == 0
  				|| strcasecmp(output->wlr_output->name, name_or_id) == 0) {
  			return output;
  		}
  	}
  	return NULL;
  }
  
  struct surface_iterator_data {
  	sway_surface_iterator_func_t user_iterator;
  	void *user_data;
  
  	struct sway_output *output;
  	struct sway_view *view;
  	double ox, oy;
  	int width, height;
  };
  
  static bool get_surface_box(struct surface_iterator_data *data,
  		struct wlr_surface *surface, int sx, int sy,
  		struct wlr_box *surface_box) {
  	struct sway_output *output = data->output;
  
  	if (!wlr_surface_has_buffer(surface)) {
  		return false;
  	}
  
  	int sw = surface->current.width;
  	int sh = surface->current.height;
  
  	struct wlr_box box = {
  		.x = floor(data->ox + sx),
  		.y = floor(data->oy + sy),
  		.width = sw,
  		.height = sh,
  	};
  	if (surface_box != NULL) {
  		memcpy(surface_box, &box, sizeof(struct wlr_box));
  	}
  
  	struct wlr_box output_box = {
  		.width = output->width,
  		.height = output->height,
  	};
  
  	struct wlr_box intersection;
  	return wlr_box_intersection(&intersection, &output_box, &box);
  }
  
  static void output_for_each_surface_iterator(struct wlr_surface *surface,
  		int sx, int sy, void *_data) {
  	struct surface_iterator_data *data = _data;
  
  	struct wlr_box box;
  	bool intersects = get_surface_box(data, surface, sx, sy, &box);
  	if (!intersects) {
  		return;
  	}
  
  	data->user_iterator(data->output, data->view, surface, &box,
  		data->user_data);
  }
  
  void output_surface_for_each_surface(struct sway_output *output,
  		struct wlr_surface *surface, double ox, double oy,
  		sway_surface_iterator_func_t iterator, void *user_data) {
  	struct surface_iterator_data data = {
  		.user_iterator = iterator,
  		.user_data = user_data,
  		.output = output,
  		.view = NULL,
  		.ox = ox,
  		.oy = oy,
  		.width = surface->current.width,
  		.height = surface->current.height,
  	};
  
  	wlr_surface_for_each_surface(surface,
  		output_for_each_surface_iterator, &data);
  }
  
  void output_view_for_each_surface(struct sway_output *output,
  		struct sway_view *view, sway_surface_iterator_func_t iterator,
  		void *user_data) {
  	struct surface_iterator_data data = {
  		.user_iterator = iterator,
  		.user_data = user_data,
  		.output = output,
  		.view = view,
  		.ox = view->container->surface_x - output->lx
  			- view->geometry.x,
  		.oy = view->container->surface_y - output->ly
  			- view->geometry.y,
  		.width = view->container->current.content_width,
  		.height = view->container->current.content_height,
  	};
  
  	view_for_each_surface(view, output_for_each_surface_iterator, &data);
  }
  
  void output_view_for_each_popup_surface(struct sway_output *output,
  		struct sway_view *view, sway_surface_iterator_func_t iterator,
  		void *user_data) {
  	struct surface_iterator_data data = {
  		.user_iterator = iterator,
  		.user_data = user_data,
  		.output = output,
  		.view = view,
  		.ox = view->container->surface_x - output->lx
  			- view->geometry.x,
  		.oy = view->container->surface_y - output->ly
  			- view->geometry.y,
  		.width = view->container->current.content_width,
  		.height = view->container->current.content_height,
  	};
  
  	view_for_each_popup_surface(view, output_for_each_surface_iterator, &data);
  }
  
  void output_layer_for_each_surface(struct sway_output *output,
  		struct wl_list *layer_surfaces, sway_surface_iterator_func_t iterator,
  		void *user_data) {
  	struct sway_layer_surface *layer_surface;
  	wl_list_for_each(layer_surface, layer_surfaces, link) {
  		struct wlr_layer_surface_v1 *wlr_layer_surface_v1 =
  			layer_surface->layer_surface;
  		struct wlr_surface *surface = wlr_layer_surface_v1->surface;
  		struct surface_iterator_data data = {
  			.user_iterator = iterator,
  			.user_data = user_data,
  			.output = output,
  			.view = NULL,
  			.ox = layer_surface->geo.x,
  			.oy = layer_surface->geo.y,
  			.width = surface->current.width,
  			.height = surface->current.height,
  		};
  		wlr_layer_surface_v1_for_each_surface(wlr_layer_surface_v1,
  			output_for_each_surface_iterator, &data);
  	}
  }
  
  void output_layer_for_each_toplevel_surface(struct sway_output *output,
  		struct wl_list *layer_surfaces, sway_surface_iterator_func_t iterator,
  		void *user_data) {
  	struct sway_layer_surface *layer_surface;
  	wl_list_for_each(layer_surface, layer_surfaces, link) {
  		struct wlr_layer_surface_v1 *wlr_layer_surface_v1 =
  			layer_surface->layer_surface;
  		output_surface_for_each_surface(output, wlr_layer_surface_v1->surface,
  			layer_surface->geo.x, layer_surface->geo.y, iterator,
  			user_data);
  	}
  }
  
  
  void output_layer_for_each_popup_surface(struct sway_output *output,
  		struct wl_list *layer_surfaces, sway_surface_iterator_func_t iterator,
  		void *user_data) {
  	struct sway_layer_surface *layer_surface;
  	wl_list_for_each(layer_surface, layer_surfaces, link) {
  		struct wlr_layer_surface_v1 *wlr_layer_surface_v1 =
  			layer_surface->layer_surface;
  		struct wlr_surface *surface = wlr_layer_surface_v1->surface;
  		struct surface_iterator_data data = {
  			.user_iterator = iterator,
  			.user_data = user_data,
  			.output = output,
  			.view = NULL,
  			.ox = layer_surface->geo.x,
  			.oy = layer_surface->geo.y,
  			.width = surface->current.width,
  			.height = surface->current.height,
  		};
  		wlr_layer_surface_v1_for_each_popup_surface(wlr_layer_surface_v1,
  			output_for_each_surface_iterator, &data);
  	}
  }
  
  #if HAVE_XWAYLAND
  void output_unmanaged_for_each_surface(struct sway_output *output,
  		struct wl_list *unmanaged, sway_surface_iterator_func_t iterator,
  		void *user_data) {
  	struct sway_xwayland_unmanaged *unmanaged_surface;
  	wl_list_for_each(unmanaged_surface, unmanaged, link) {
  		struct wlr_xwayland_surface *xsurface =
  			unmanaged_surface->wlr_xwayland_surface;
  		double ox = unmanaged_surface->lx - output->lx;
  		double oy = unmanaged_surface->ly - output->ly;
  
  		output_surface_for_each_surface(output, xsurface->surface, ox, oy,
  			iterator, user_data);
  	}
  }
  #endif
  
  void output_drag_icons_for_each_surface(struct sway_output *output,
  		struct wl_list *drag_icons, sway_surface_iterator_func_t iterator,
  		void *user_data) {
  	struct sway_drag_icon *drag_icon;
  	wl_list_for_each(drag_icon, drag_icons, link) {
  		double ox = drag_icon->x - output->lx;
  		double oy = drag_icon->y - output->ly;
  
  		if (drag_icon->wlr_drag_icon->mapped) {
  			output_surface_for_each_surface(output,
  				drag_icon->wlr_drag_icon->surface, ox, oy,
  				iterator, user_data);
  		}
  	}
  }
  
  static void for_each_surface_container_iterator(struct sway_container *con,
  		void *_data) {
  	if (!con->view || !view_is_visible(con->view)) {
  		return;
  	}
  
  	struct surface_iterator_data *data = _data;
  	output_view_for_each_surface(data->output, con->view,
  		data->user_iterator, data->user_data);
  }
  
  static void output_for_each_surface(struct sway_output *output,
  		sway_surface_iterator_func_t iterator, void *user_data) {
  	if (output_has_opaque_overlay_layer_surface(output)) {
  		goto overlay;
  	}
  
  	struct surface_iterator_data data = {
  		.user_iterator = iterator,
  		.user_data = user_data,
  		.output = output,
  		.view = NULL,
  	};
  
  	struct sway_workspace *workspace = output_get_active_workspace(output);
  	struct sway_container *fullscreen_con = root->fullscreen_global;
  	if (!fullscreen_con) {
  		if (!workspace) {
  			return;
  		}
  		fullscreen_con = workspace->current.fullscreen;
  	}
  	if (fullscreen_con) {
  		for_each_surface_container_iterator(fullscreen_con, &data);
  		container_for_each_child(fullscreen_con,
  			for_each_surface_container_iterator, &data);
  
  		// TODO: Show transient containers for fullscreen global
  		if (fullscreen_con == workspace->current.fullscreen) {
  			for (int i = 0; i < workspace->current.floating->length; ++i) {
  				struct sway_container *floater =
  					workspace->current.floating->items[i];
  				if (container_is_transient_for(floater, fullscreen_con)) {
  					for_each_surface_container_iterator(floater, &data);
  				}
  			}
  		}
  #if HAVE_XWAYLAND
  		output_unmanaged_for_each_surface(output, &root->xwayland_unmanaged,
  			iterator, user_data);
  #endif
  	} else {
  		output_layer_for_each_surface(output,
  			&output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BACKGROUND],
  			iterator, user_data);
  		output_layer_for_each_surface(output,
  			&output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM],
  			iterator, user_data);
  
  		workspace_for_each_container(workspace,
  			for_each_surface_container_iterator, &data);
  
  #if HAVE_XWAYLAND
  		output_unmanaged_for_each_surface(output, &root->xwayland_unmanaged,
  			iterator, user_data);
  #endif
  		output_layer_for_each_surface(output,
  			&output->layers[ZWLR_LAYER_SHELL_V1_LAYER_TOP],
  			iterator, user_data);
  	}
  
  overlay:
  	output_layer_for_each_surface(output,
  		&output->layers[ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY],
  		iterator, user_data);
  	output_drag_icons_for_each_surface(output, &root->drag_icons,
  		iterator, user_data);
  }
  
  static int scale_length(int length, int offset, float scale) {
  	return round((offset + length) * scale) - round(offset * scale);
  }
  
  void scale_box(struct wlr_box *box, float scale) {
  	box->width = scale_length(box->width, box->x, scale);
  	box->height = scale_length(box->height, box->y, scale);
  	box->x = round(box->x * scale);
  	box->y = round(box->y * scale);
  }
  
  struct sway_workspace *output_get_active_workspace(struct sway_output *output) {
  	struct sway_seat *seat = input_manager_current_seat();
  	struct sway_node *focus = seat_get_active_tiling_child(seat, &output->node);
  	if (!focus) {
  		if (!output->workspaces->length) {
  			return NULL;
  		}
  		return output->workspaces->items[0];
  	}
  	return focus->sway_workspace;
  }
  
  bool output_has_opaque_overlay_layer_surface(struct sway_output *output) {
  	struct sway_layer_surface *sway_layer_surface;
  	wl_list_for_each(sway_layer_surface,
  			&output->layers[ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY], link) {
  		struct wlr_surface *wlr_surface = sway_layer_surface->layer_surface->surface;
  		pixman_box32_t output_box = {
  			.x2 = output->width,
  			.y2 = output->height,
  		};
  		pixman_region32_t surface_opaque_box;
  		pixman_region32_init(&surface_opaque_box);
  		pixman_region32_copy(&surface_opaque_box, &wlr_surface->opaque_region);
  		pixman_region32_translate(&surface_opaque_box,
  			sway_layer_surface->geo.x, sway_layer_surface->geo.y);
  		pixman_region_overlap_t contains =
  			pixman_region32_contains_rectangle(&surface_opaque_box, &output_box);
  		pixman_region32_fini(&surface_opaque_box);
  
  		if (contains == PIXMAN_REGION_IN) {
  			return true;
  		}
  	}
  	return false;
  }
  
  struct send_frame_done_data {
  	struct timespec when;
  	int msec_until_refresh;
  };
  
  static void send_frame_done_iterator(struct sway_output *output,
  		struct sway_view *view, struct wlr_surface *surface,
  		struct wlr_box *box, void *user_data) {
  	int view_max_render_time = 0;
  	if (view != NULL) {
  		view_max_render_time = view->max_render_time;
  	}
  
  	struct send_frame_done_data *data = user_data;
  
  	int delay = data->msec_until_refresh - output->max_render_time
  			- view_max_render_time;
  
  	if (output->max_render_time == 0 || view_max_render_time == 0 || delay < 1) {
  		wlr_surface_send_frame_done(surface, &data->when);
  	} else {
  		struct sway_surface *sway_surface = surface->data;
  		wl_event_source_timer_update(sway_surface->frame_done_timer, delay);
  	}
  }
  
  static void send_frame_done(struct sway_output *output, struct send_frame_done_data *data) {
  	output_for_each_surface(output, send_frame_done_iterator, data);
  }
  
  static void count_surface_iterator(struct sway_output *output,
  		struct sway_view *view, struct wlr_surface *surface,
  		struct wlr_box *box, void *data) {
  	size_t *n = data;
  	(*n)++;
  }
  
  static bool scan_out_fullscreen_view(struct sway_output *output,
  		struct sway_view *view) {
  	struct wlr_output *wlr_output = output->wlr_output;
  	struct sway_workspace *workspace = output->current.active_workspace;
  	if (!sway_assert(workspace, "Expected an active workspace")) {
  		return false;
  	}
  
  	if (!wl_list_empty(&view->saved_buffers)) {
  		return false;
  	}
  
  	for (int i = 0; i < workspace->current.floating->length; ++i) {
  		struct sway_container *floater =
  			workspace->current.floating->items[i];
  		if (container_is_transient_for(floater, view->container)) {
  			return false;
  		}
  	}
  
  #if HAVE_XWAYLAND
  	if (!wl_list_empty(&root->xwayland_unmanaged)) {
  		return false;
  	}
  #endif
  
  	if (!wl_list_empty(&output->layers[ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY])) {
  		return false;
  	}
  	if (!wl_list_empty(&root->drag_icons)) {
  		return false;
  	}
  
  	struct wlr_surface *surface = view->surface;
  	if (surface == NULL) {
  		return false;
  	}
  	size_t n_surfaces = 0;
  	output_view_for_each_surface(output, view,
  		count_surface_iterator, &n_surfaces);
  	if (n_surfaces != 1) {
  		return false;
  	}
  
  	if (surface->buffer == NULL) {
  		return false;
  	}
  
  	if ((float)surface->current.scale != wlr_output->scale ||
  			surface->current.transform != wlr_output->transform) {
  		return false;
  	}
  
  	wlr_output_attach_buffer(wlr_output, &surface->buffer->base);
  	if (!wlr_output_test(wlr_output)) {
  		return false;
  	}
  
  	wlr_presentation_surface_sampled_on_output(server.presentation, surface,
  		wlr_output);
  
  	return wlr_output_commit(wlr_output);
  }
  
  static int output_repaint_timer_handler(void *data) {
  	struct sway_output *output = data;
  	if (output->wlr_output == NULL) {
  		return 0;
  	}
  
  	output->wlr_output->frame_pending = false;
  
  	struct sway_workspace *workspace = output->current.active_workspace;
  	if (workspace == NULL) {
  		return 0;
  	}
  
  	struct sway_container *fullscreen_con = root->fullscreen_global;
  	if (!fullscreen_con) {
  		fullscreen_con = workspace->current.fullscreen;
  	}
  
  	if (fullscreen_con && fullscreen_con->view && !debug.noscanout) {
  		// Try to scan-out the fullscreen view
  		static bool last_scanned_out = false;
  		bool scanned_out =
  			scan_out_fullscreen_view(output, fullscreen_con->view);
  
  		if (scanned_out && !last_scanned_out) {
  			sway_log(SWAY_DEBUG, "Scanning out fullscreen view on %s",
  				output->wlr_output->name);
  		}
  		if (last_scanned_out && !scanned_out) {
  			sway_log(SWAY_DEBUG, "Stopping fullscreen view scan out on %s",
  				output->wlr_output->name);
  			output_damage_whole(output);
  		}
  		last_scanned_out = scanned_out;
  
  		if (scanned_out) {
  			return 0;
  		}
  	}
  
  	bool needs_frame;
  	pixman_region32_t damage;
  	pixman_region32_init(&damage);
  	if (!wlr_output_damage_attach_render(output->damage,
  			&needs_frame, &damage)) {
  		return 0;
  	}
  
  	if (needs_frame) {
  		struct timespec now;
  		clock_gettime(CLOCK_MONOTONIC, &now);
  
  		output_render(output, &now, &damage);
  	} else {
  		wlr_output_rollback(output->wlr_output);
  	}
  
  	pixman_region32_fini(&damage);
  
  	return 0;
  }
  
  static void damage_handle_frame(struct wl_listener *listener, void *user_data) {
  	struct sway_output *output =
  		wl_container_of(listener, output, damage_frame);
  	if (!output->enabled || !output->wlr_output->enabled) {
  		return;
  	}
  
  	// Compute predicted milliseconds until the next refresh. It's used for
  	// delaying both output rendering and surface frame callbacks.
  	int msec_until_refresh = 0;
  
  	if (output->max_render_time != 0) {
  		struct timespec now;
  		clockid_t presentation_clock
  			= wlr_backend_get_presentation_clock(server.backend);
  		clock_gettime(presentation_clock, &now);
  
  		const long NSEC_IN_SECONDS = 1000000000;
  		struct timespec predicted_refresh = output->last_presentation;
  		predicted_refresh.tv_nsec += output->refresh_nsec % NSEC_IN_SECONDS;
  		predicted_refresh.tv_sec += output->refresh_nsec / NSEC_IN_SECONDS;
  		if (predicted_refresh.tv_nsec >= NSEC_IN_SECONDS) {
  			predicted_refresh.tv_sec += 1;
  			predicted_refresh.tv_nsec -= NSEC_IN_SECONDS;
  		}
  
  		// If the predicted refresh time is before the current time then
  		// there's no point in delaying.
  		//
  		// We only check tv_sec because if the predicted refresh time is less
  		// than a second before the current time, then msec_until_refresh will
  		// end up slightly below zero, which will effectively disable the delay
  		// without potential disastrous negative overflows that could occur if
  		// tv_sec was not checked.
  		if (predicted_refresh.tv_sec >= now.tv_sec) {
  			long nsec_until_refresh
  				= (predicted_refresh.tv_sec - now.tv_sec) * NSEC_IN_SECONDS
  					+ (predicted_refresh.tv_nsec - now.tv_nsec);
  
  			// We want msec_until_refresh to be conservative, that is, floored.
  			// If we have 7.9 msec until refresh, we better compute the delay
  			// as if we had only 7 msec, so that we don't accidentally delay
  			// more than necessary and miss a frame.
  			msec_until_refresh = nsec_until_refresh / 1000000;
  		}
  	}
  
  	int delay = msec_until_refresh - output->max_render_time;
  
  	// If the delay is less than 1 millisecond (which is the least we can wait)
  	// then just render right away.
  	if (delay < 1) {
  		output_repaint_timer_handler(output);
  	} else {
  		output->wlr_output->frame_pending = true;
  		wl_event_source_timer_update(output->repaint_timer, delay);
  	}
  
  	// Send frame done to all visible surfaces
  	struct send_frame_done_data data = {0};
  	clock_gettime(CLOCK_MONOTONIC, &data.when);
  	data.msec_until_refresh = msec_until_refresh;
  	send_frame_done(output, &data);
  }
  
  void output_damage_whole(struct sway_output *output) {
  	// The output can exist with no wlr_output if it's just been disconnected
  	// and the transaction to evacuate it has't completed yet.
  	if (output && output->wlr_output && output->damage) {
  		wlr_output_damage_add_whole(output->damage);
  	}
  }
  
  static void damage_surface_iterator(struct sway_output *output,
  		struct sway_view *view, struct wlr_surface *surface,
  		struct wlr_box *_box, void *_data) {
  	bool *data = _data;
  	bool whole = *data;
  
  	struct wlr_box box = *_box;
  	scale_box(&box, output->wlr_output->scale);
  
  	if (pixman_region32_not_empty(&surface->buffer_damage)) {
  		pixman_region32_t damage;
  		pixman_region32_init(&damage);
  		wlr_surface_get_effective_damage(surface, &damage);
  		wlr_region_scale(&damage, &damage, output->wlr_output->scale);
  		if (ceil(output->wlr_output->scale) > surface->current.scale) {
  			// When scaling up a surface, it'll become blurry so we need to
  			// expand the damage region
  			wlr_region_expand(&damage, &damage,
  				ceil(output->wlr_output->scale) - surface->current.scale);
  		}
  		pixman_region32_translate(&damage, box.x, box.y);
  		wlr_output_damage_add(output->damage, &damage);
  		pixman_region32_fini(&damage);
  	}
  
  	if (whole) {
  		wlr_output_damage_add_box(output->damage, &box);
  	}
  
  	if (!wl_list_empty(&surface->current.frame_callback_list)) {
  		wlr_output_schedule_frame(output->wlr_output);
  	}
  }
  
  void output_damage_surface(struct sway_output *output, double ox, double oy,
  		struct wlr_surface *surface, bool whole) {
  	output_surface_for_each_surface(output, surface, ox, oy,
  		damage_surface_iterator, &whole);
  }
  
  void output_damage_from_view(struct sway_output *output,
  		struct sway_view *view) {
  	if (!view_is_visible(view)) {
  		return;
  	}
  	bool whole = false;
  	output_view_for_each_surface(output, view, damage_surface_iterator, &whole);
  }
  
  // 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->lx;
  	box.y -= output->ly;
  	scale_box(&box, output->wlr_output->scale);
  	wlr_output_damage_add_box(output->damage, &box);
  }
  
  static void damage_child_views_iterator(struct sway_container *con,
  		void *data) {
  	if (!con->view || !view_is_visible(con->view)) {
  		return;
  	}
  	struct sway_output *output = data;
  	bool whole = true;
  	output_view_for_each_surface(output, con->view, damage_surface_iterator,
  			&whole);
  }
  
  void output_damage_whole_container(struct sway_output *output,
  		struct sway_container *con) {
  	// Pad the box by 1px, because the width is a double and might be a fraction
  	struct wlr_box box = {
  		.x = con->current.x - output->lx - 1,
  		.y = con->current.y - output->ly - 1,
  		.width = con->current.width + 2,
  		.height = con->current.height + 2,
  	};
  	scale_box(&box, output->wlr_output->scale);
  	wlr_output_damage_add_box(output->damage, &box);
  	// Damage subsurfaces as well, which may extend outside the box
  	if (con->view) {
  		damage_child_views_iterator(con, output);
  	} else {
  		container_for_each_child(con, damage_child_views_iterator, output);
  	}
  }
  
  static void damage_handle_destroy(struct wl_listener *listener, void *data) {
  	struct sway_output *output =
  		wl_container_of(listener, output, damage_destroy);
  	if (!output->enabled) {
  		return;
  	}
  	output_disable(output);
  
  	wl_list_remove(&output->damage_destroy.link);
  	wl_list_remove(&output->damage_frame.link);
  
  	transaction_commit_dirty();
  }
  
  static void update_output_manager_config(struct sway_server *server) {
  	struct wlr_output_configuration_v1 *config =
  		wlr_output_configuration_v1_create();
  
  	struct sway_output *output;
  	wl_list_for_each(output, &root->all_outputs, link) {
  		if (output == root->noop_output) {
  			continue;
  		}
  		struct wlr_output_configuration_head_v1 *config_head =
  			wlr_output_configuration_head_v1_create(config, output->wlr_output);
  		struct wlr_box *output_box = wlr_output_layout_get_box(
  			root->output_layout, output->wlr_output);
  		// We mark the output enabled even if it is switched off by DPMS
  		config_head->state.enabled = output->current_mode != NULL && output->enabled;
  		config_head->state.mode = output->current_mode;
  		if (output_box) {
  			config_head->state.x = output_box->x;
  			config_head->state.y = output_box->y;
  		}
  	}
  
  	wlr_output_manager_v1_set_configuration(server->output_manager_v1, config);
  }
  
  static void handle_destroy(struct wl_listener *listener, void *data) {
  	struct sway_output *output = wl_container_of(listener, output, destroy);
  	struct sway_server *server = output->server;
  	wl_signal_emit(&output->events.destroy, output);
  
  	if (output->enabled) {
  		output_disable(output);
  	}
  	output_begin_destroy(output);
  
  	wl_list_remove(&output->destroy.link);
  	wl_list_remove(&output->commit.link);
  	wl_list_remove(&output->mode.link);
  	wl_list_remove(&output->present.link);
  
  	transaction_commit_dirty();
  
  	update_output_manager_config(server);
  }
  
  static void handle_mode(struct wl_listener *listener, void *data) {
  	struct sway_output *output = wl_container_of(listener, output, mode);
  	if (!output->enabled && !output->enabling) {
  		struct output_config *oc = find_output_config(output);
  		if (output->wlr_output->current_mode != NULL &&
  				(!oc || oc->enabled)) {
  			// We want to enable this output, but it didn't work last time,
  			// possibly because we hadn't enough CRTCs. Try again now that the
  			// output has a mode.
  			sway_log(SWAY_DEBUG, "Output %s has gained a CRTC, "
  				"trying to enable it", output->wlr_output->name);
  			apply_output_config(oc, output);
  		}
  		return;
  	}
  	if (!output->enabled) {
  		return;
  	}
  	arrange_layers(output);
  	arrange_output(output);
  	transaction_commit_dirty();
  
  	update_output_manager_config(output->server);
  }
  
  static void update_textures(struct sway_container *con, void *data) {
  	container_update_title_textures(con);
  	container_update_marks_textures(con);
  }
  
  static void handle_commit(struct wl_listener *listener, void *data) {
  	struct sway_output *output = wl_container_of(listener, output, commit);
  	struct wlr_output_event_commit *event = data;
  
  	if (!output->enabled) {
  		return;
  	}
  
  	if (event->committed & WLR_OUTPUT_STATE_SCALE) {
  		output_for_each_container(output, update_textures, NULL);
  	}
  
  	if (event->committed & (WLR_OUTPUT_STATE_TRANSFORM | WLR_OUTPUT_STATE_SCALE)) {
  		arrange_layers(output);
  		arrange_output(output);
  		transaction_commit_dirty();
  
  		update_output_manager_config(output->server);
  	}
  }
  
  static void handle_present(struct wl_listener *listener, void *data) {
  	struct sway_output *output = wl_container_of(listener, output, present);
  	struct wlr_output_event_present *output_event = data;
  
  	if (!output->enabled || !output_event->presented) {
  		return;
  	}
  
  	output->last_presentation = *output_event->when;
  	output->refresh_nsec = output_event->refresh;
  }
  
  void handle_new_output(struct wl_listener *listener, void *data) {
  	struct sway_server *server = wl_container_of(listener, server, new_output);
  	struct wlr_output *wlr_output = data;
  	sway_log(SWAY_DEBUG, "New output %p: %s (non-desktop: %d)",
  			wlr_output, wlr_output->name, wlr_output->non_desktop);
  
  	if (wlr_output->non_desktop) {
  		sway_log(SWAY_DEBUG, "Not configuring non-desktop output");
  		if (server->drm_lease_manager) {
  			wlr_drm_lease_v1_manager_offer_output(server->drm_lease_manager,
  					wlr_output);
  		}
  		return;
  	}
  
  	if (!wlr_output_init_render(wlr_output, server->allocator,
  			server->renderer)) {
  		sway_log(SWAY_ERROR, "Failed to init output render");
  		return;
  	}
  
  	struct sway_output *output = output_create(wlr_output);
  	if (!output) {
  		return;
  	}
  	output->server = server;
  	output->damage = wlr_output_damage_create(wlr_output);
  
  	wl_signal_add(&wlr_output->events.destroy, &output->destroy);
  	output->destroy.notify = handle_destroy;
  	wl_signal_add(&wlr_output->events.commit, &output->commit);
  	output->commit.notify = handle_commit;
  	wl_signal_add(&wlr_output->events.mode, &output->mode);
  	output->mode.notify = handle_mode;
  	wl_signal_add(&wlr_output->events.present, &output->present);
  	output->present.notify = handle_present;
  	wl_signal_add(&output->damage->events.frame, &output->damage_frame);
  	output->damage_frame.notify = damage_handle_frame;
  	wl_signal_add(&output->damage->events.destroy, &output->damage_destroy);
  	output->damage_destroy.notify = damage_handle_destroy;
  
  	output->repaint_timer = wl_event_loop_add_timer(server->wl_event_loop,
  		output_repaint_timer_handler, output);
  
  	struct output_config *oc = find_output_config(output);
  	apply_output_config(oc, output);
  	free_output_config(oc);
  
  	transaction_commit_dirty();
  
  	update_output_manager_config(server);
  }
  
  void handle_output_layout_change(struct wl_listener *listener,
  		void *data) {
  	struct sway_server *server =
  		wl_container_of(listener, server, output_layout_change);
  	update_output_manager_config(server);
  }
  
  static void output_manager_apply(struct sway_server *server,
  		struct wlr_output_configuration_v1 *config, bool test_only) {
  	// TODO: perform atomic tests on the whole backend atomically
  
  	struct wlr_output_configuration_head_v1 *config_head;
  	// First disable outputs we need to disable
  	bool ok = true;
  	wl_list_for_each(config_head, &config->heads, link) {
  		struct wlr_output *wlr_output = config_head->state.output;
  		struct sway_output *output = wlr_output->data;
  		if (!output->enabled || config_head->state.enabled) {
  			continue;
  		}
  		struct output_config *oc = new_output_config(output->wlr_output->name);
  		oc->enabled = false;
  
  		if (test_only) {
  			ok &= test_output_config(oc, output);
  		} else {
  			oc = store_output_config(oc);
  			ok &= apply_output_config(oc, output);
  		}
  	}
  
  	// Then enable outputs that need to
  	wl_list_for_each(config_head, &config->heads, link) {
  		struct wlr_output *wlr_output = config_head->state.output;
  		struct sway_output *output = wlr_output->data;
  		if (!config_head->state.enabled) {
  			continue;
  		}
  		struct output_config *oc = new_output_config(output->wlr_output->name);
  		oc->enabled = true;
  		if (config_head->state.mode != NULL) {
  			struct wlr_output_mode *mode = config_head->state.mode;
  			oc->width = mode->width;
  			oc->height = mode->height;
  			oc->refresh_rate = mode->refresh / 1000.f;
  		} else {
  			oc->width = config_head->state.custom_mode.width;
  			oc->height = config_head->state.custom_mode.height;
  			oc->refresh_rate =
  				config_head->state.custom_mode.refresh / 1000.f;
  		}
  		oc->x = config_head->state.x;
  		oc->y = config_head->state.y;
  		oc->transform = config_head->state.transform;
  		oc->scale = config_head->state.scale;
  
  		if (test_only) {
  			ok &= test_output_config(oc, output);
  		} else {
  			oc = store_output_config(oc);
  			ok &= apply_output_config(oc, output);
  		}
  	}
  
  	if (ok) {
  		wlr_output_configuration_v1_send_succeeded(config);
  	} else {
  		wlr_output_configuration_v1_send_failed(config);
  	}
  	wlr_output_configuration_v1_destroy(config);
  
  	if (!test_only) {
  		update_output_manager_config(server);
  	}
  }
  
  void handle_output_manager_apply(struct wl_listener *listener, void *data) {
  	struct sway_server *server =
  		wl_container_of(listener, server, output_manager_apply);
  	struct wlr_output_configuration_v1 *config = data;
  
  	output_manager_apply(server, config, false);
  }
  
  void handle_output_manager_test(struct wl_listener *listener, void *data) {
  	struct sway_server *server =
  		wl_container_of(listener, server, output_manager_test);
  	struct wlr_output_configuration_v1 *config = data;
  
  	output_manager_apply(server, config, true);
  }
  
  void handle_output_power_manager_set_mode(struct wl_listener *listener,
  		void *data) {
  	struct wlr_output_power_v1_set_mode_event *event = data;
  	struct sway_output *output = event->output->data;
  
  	struct output_config *oc = new_output_config(output->wlr_output->name);
  	switch (event->mode) {
  	case ZWLR_OUTPUT_POWER_V1_MODE_OFF:
  		oc->dpms_state = DPMS_OFF;
  		break;
  	case ZWLR_OUTPUT_POWER_V1_MODE_ON:
  		oc->dpms_state = DPMS_ON;
  		break;
  	}
  	oc = store_output_config(oc);
  	apply_output_config(oc, output);
  }
  