surface: redesign state

include/wlr/types/wlr_surface.h

@@ -8,57 +8,32 @@
 #include <wayland-server.h>
 #include <wlr/types/wlr_output.h>
 
-#define WLR_SURFACE_INVALID_BUFFER 1
-#define WLR_SURFACE_INVALID_SURFACE_DAMAGE 2
-#define WLR_SURFACE_INVALID_BUFFER_DAMAGE 4
-#define WLR_SURFACE_INVALID_OPAQUE_REGION 8
-#define WLR_SURFACE_INVALID_INPUT_REGION 16
-#define WLR_SURFACE_INVALID_TRANSFORM 32
-#define WLR_SURFACE_INVALID_SCALE 64
-#define WLR_SURFACE_INVALID_SUBSURFACE_POSITION 128
-#define WLR_SURFACE_INVALID_FRAME_CALLBACK_LIST 256
+enum wlr_surface_state_field {
+	WLR_SURFACE_STATE_BUFFER = 1,
+	WLR_SURFACE_STATE_SURFACE_DAMAGE = 2,
+	WLR_SURFACE_STATE_BUFFER_DAMAGE = 4,
+	WLR_SURFACE_STATE_OPAQUE_REGION = 8,
+	WLR_SURFACE_STATE_INPUT_REGION = 16,
+	WLR_SURFACE_STATE_TRANSFORM = 32,
+	WLR_SURFACE_STATE_SCALE = 64,
+	WLR_SURFACE_STATE_FRAME_CALLBACK_LIST = 128,
+};
 
 struct wlr_surface_state {
-	uint32_t invalid;
-	struct wl_resource *buffer;
-	struct wl_listener buffer_destroy_listener;
-	int32_t sx, sy;
+	uint32_t committed; // enum wlr_surface_state_field
+
+	struct wl_resource *buffer_resource;
+	int32_t dx, dy; // relative to previous position
 	pixman_region32_t surface_damage, buffer_damage;
 	pixman_region32_t opaque, input;
 	enum wl_output_transform transform;
 	int32_t scale;
-	int width, height;
-	int buffer_width, buffer_height;
-
-	struct {
-		int32_t x, y;
-	} subsurface_position;
-
-	struct wl_list frame_callback_list; // wl_surface.frame
-};
-
-struct wlr_subsurface {
-	struct wl_resource *resource;
-	struct wlr_surface *surface;
-	struct wlr_surface *parent;
-
-	struct wlr_surface_state *cached;
-	bool has_cache;
-
-	bool synchronized;
-	bool reordered;
-
-	struct wl_list parent_link;
-	struct wl_list parent_pending_link;
-
-	struct wl_listener surface_destroy;
-	struct wl_listener parent_destroy;
+	struct wl_list frame_callback_list; // wl_resource
 
-	struct {
-		struct wl_signal destroy;
-	} events;
+	int width, height; // in surface-local coordinates
+	int buffer_width, buffer_height;
 
-	void *data;
+	struct wl_listener buffer_destroy;
 };
 
 struct wlr_surface {
@@ -71,7 +46,28 @@ struct wlr_surface {
 	 * or something went wrong with uploading the buffer.
 	 */
 	struct wlr_buffer *buffer;
-	struct wlr_surface_state *current, *pending;
+	/**
+	 * The buffer position, in surface-local units.
+	 */
+	int sx, sy;
+	/**
+	 * The last commit's buffer damage, in buffer-local coordinates. This
+	 * contains both the damage accumulated by the client via
+	 * `wlr_surface_state.surface_damage` and `wlr_surface_state.buffer_damage`.
+	 * If the buffer has changed its size or moved, the whole buffer is
+	 * damaged.
+	 *
+	 * This region needs to be scaled and transformed into output coordinates,
+	 * just like the buffer's texture.
+	 */
+	pixman_region32_t buffer_damage;
+	/**
+	 * `current` contains the current, committed surface state. `pending`
+	 * accumulates state changes from the client between commits and shouldn't
+	 * be accessed by the compositor directly. `previous` contains the state of
+	 * the previous commit.
+	 */
+	struct wlr_surface_state current, pending, previous;
 	const char *role; // the lifetime-bound role or null
 
 	struct {
@@ -94,6 +90,36 @@ struct wlr_surface {
 	void *data;
 };
 
+struct wlr_subsurface_state {
+	int32_t x, y;
+};
+
+struct wlr_subsurface {
+	struct wl_resource *resource;
+	struct wlr_surface *surface;
+	struct wlr_surface *parent;
+
+	struct wlr_subsurface_state current, pending;
+
+	struct wlr_surface_state cached;
+	bool has_cache;
+
+	bool synchronized;
+	bool reordered;
+
+	struct wl_list parent_link;
+	struct wl_list parent_pending_link;
+
+	struct wl_listener surface_destroy;
+	struct wl_listener parent_destroy;
+
+	struct {
+		struct wl_signal destroy;
+	} events;
+
+	void *data;
+};
+
 typedef void (*wlr_surface_iterator_func_t)(struct wlr_surface *surface,
 	int sx, int sy, void *data);
 

rootston/cursor.c

@@ -200,8 +200,8 @@ static void roots_cursor_update_position(
 	case ROOTS_CURSOR_ROTATE:
 		view = roots_seat_get_focus(seat);
 		if (view != NULL) {
-			int ox = view->x + view->wlr_surface->current->width/2,
-				oy = view->y + view->wlr_surface->current->height/2;
+			int ox = view->x + view->wlr_surface->current.width/2,
+				oy = view->y + view->wlr_surface->current.height/2;
 			int ux = cursor->offs_x - ox,
 				uy = cursor->offs_y - oy;
 			int vx = cursor->cursor->x - ox,
@@ -239,12 +239,12 @@ static void roots_cursor_press_button(struct roots_cursor *cursor,
 			break;
 		case BTN_RIGHT:
 			edges = 0;
-			if (sx < view->wlr_surface->current->width/2) {
+			if (sx < view->wlr_surface->current.width/2) {
 				edges |= WLR_EDGE_LEFT;
 			} else {
 				edges |= WLR_EDGE_RIGHT;
 			}
-			if (sy < view->wlr_surface->current->height/2) {
+			if (sy < view->wlr_surface->current.height/2) {
 				edges |= WLR_EDGE_TOP;
 			} else {
 				edges |= WLR_EDGE_BOTTOM;

rootston/desktop.c

@@ -69,8 +69,8 @@ enum roots_deco_part view_get_deco_part(struct roots_view *view, double sx,
 		return ROOTS_DECO_PART_NONE;
 	}
 
-	int sw = view->wlr_surface->current->width;
-	int sh = view->wlr_surface->current->height;
+	int sw = view->wlr_surface->current.width;
+	int sh = view->wlr_surface->current.height;
 	int bw = view->border_width;
 	int titlebar_h = view->titlebar_height;
 
@@ -558,7 +558,7 @@ static bool view_at(struct roots_view *view, double lx, double ly,
 	double view_sx = lx - view->x;
 	double view_sy = ly - view->y;
 
-	struct wlr_surface_state *state = view->wlr_surface->current;
+	struct wlr_surface_state *state = &view->wlr_surface->current;
 	struct wlr_box box = {
 		.x = 0, .y = 0,
 		.width = state->width, .height = state->height,

rootston/output.c

@@ -44,8 +44,8 @@ struct layout_data {
 static void get_layout_position(struct layout_data *data, double *lx, double *ly,
 		const struct wlr_surface *surface, int sx, int sy) {
 	double _sx = sx, _sy = sy;
-	rotate_child_position(&_sx, &_sy, surface->current->width,
-		surface->current->height, data->width, data->height, data->rotation);
+	rotate_child_position(&_sx, &_sy, surface->current.width,
+		surface->current.height, data->width, data->height, data->rotation);
 	*lx = data->x + _sx;
 	*ly = data->y + _sy;
 }
@@ -55,8 +55,8 @@ static void surface_for_each_surface(struct wlr_surface *surface,
 		wlr_surface_iterator_func_t iterator, void *user_data) {
 	layout_data->x = lx;
 	layout_data->y = ly;
-	layout_data->width = surface->current->width;
-	layout_data->height = surface->current->height;
+	layout_data->width = surface->current.width;
+	layout_data->height = surface->current.height;
 	layout_data->rotation = rotation;
 
 	wlr_surface_for_each_surface(surface, iterator, user_data);
@@ -67,8 +67,8 @@ static void view_for_each_surface(struct roots_view *view,
 		void *user_data) {
 	layout_data->x = view->x;
 	layout_data->y = view->y;
-	layout_data->width = view->wlr_surface->current->width;
-	layout_data->height = view->wlr_surface->current->height;
+	layout_data->width = view->wlr_surface->current.width;
+	layout_data->height = view->wlr_surface->current.height;
 	layout_data->rotation = view->rotation;
 
 	switch (view->type) {
@@ -146,16 +146,19 @@ static bool surface_intersect_output(struct wlr_surface *surface,
 	double ox = lx, oy = ly;
 	wlr_output_layout_output_coords(output_layout, wlr_output, &ox, &oy);
 
+	ox += surface->sx;
+	oy += surface->sy;
+
 	if (box != NULL) {
 		box->x = ox * wlr_output->scale;
 		box->y = oy * wlr_output->scale;
-		box->width = surface->current->width * wlr_output->scale;
-		box->height = surface->current->height * wlr_output->scale;
+		box->width = surface->current.width * wlr_output->scale;
+		box->height = surface->current.height * wlr_output->scale;
 	}
 
 	struct wlr_box layout_box = {
 		.x = lx, .y = ly,
-		.width = surface->current->width, .height = surface->current->height,
+		.width = surface->current.width, .height = surface->current.height,
 	};
 	wlr_box_rotated_bounds(&layout_box, rotation, &layout_box);
 	return wlr_output_layout_intersects(output_layout, wlr_output, &layout_box);
@@ -223,7 +226,7 @@ static void render_surface(struct wlr_surface *surface, int sx, int sy,
 
 	float matrix[9];
 	enum wl_output_transform transform =
-		wlr_output_transform_invert(surface->current->transform);
+		wlr_output_transform_invert(surface->current.transform);
 	wlr_matrix_project_box(matrix, &box, transform, rotation,
 		output->wlr_output->transform_matrix);
 
@@ -247,8 +250,8 @@ static void get_decoration_box(struct roots_view *view,
 	double sx = deco_box.x - view->x;
 	double sy = deco_box.y - view->y;
 	rotate_child_position(&sx, &sy, deco_box.width, deco_box.height,
-		view->wlr_surface->current->width,
-		view->wlr_surface->current->height, view->rotation);
+		view->wlr_surface->current.width,
+		view->wlr_surface->current.height, view->rotation);
 	double x = sx + view->x;
 	double y = sy + view->y;
 
@@ -692,15 +695,21 @@ static void damage_from_surface(struct wlr_surface *surface, int sx, int sy,
 	int center_x = box.x + box.width/2;
 	int center_y = box.y + box.height/2;
 
+	enum wl_output_transform transform =
+		wlr_output_transform_invert(surface->current.transform);
+
 	pixman_region32_t damage;
 	pixman_region32_init(&damage);
-	pixman_region32_copy(&damage, &surface->current->surface_damage);
-	wlr_region_scale(&damage, &damage, wlr_output->scale);
-	if (ceil(wlr_output->scale) > surface->current->scale) {
+	pixman_region32_copy(&damage, &surface->buffer_damage);
+	wlr_region_transform(&damage, &damage, transform,
+		surface->current.buffer_width, surface->current.buffer_height);
+	wlr_region_scale(&damage, &damage,
+		wlr_output->scale / (float)surface->current.scale);
+	if (ceil(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(wlr_output->scale) - surface->current->scale);
+			ceil(wlr_output->scale) - surface->current.scale);
 	}
 	pixman_region32_translate(&damage, box.x, box.y);
 	wlr_region_rotated_bounds(&damage, &damage, rotation, center_x, center_y);

rootston/wl_shell.c

@@ -158,8 +158,8 @@ static void handle_surface_commit(struct wl_listener *listener, void *data) {
 
 	view_apply_damage(view);
 
-	int width = wlr_surface->current->width;
-	int height = wlr_surface->current->height;
+	int width = wlr_surface->current.width;
+	int height = wlr_surface->current.height;
 	view_update_size(view, width, height);
 
 	double x = view->x;
@@ -236,8 +236,8 @@ void handle_wl_shell_surface(struct wl_listener *listener, void *data) {
 		return;
 	}
 	view->type = ROOTS_WL_SHELL_VIEW;
-	view->width = surface->surface->current->width;
-	view->height = surface->surface->current->height;
+	view->width = surface->surface->current.width;
+	view->height = surface->surface->current.height;
 
 	view->wl_shell_surface = surface;
 	view->roots_wl_shell_surface = roots_surface;

rootston/xwayland.c

@@ -206,8 +206,8 @@ static void handle_surface_commit(struct wl_listener *listener, void *data) {
 
 	view_apply_damage(view);
 
-	int width = wlr_surface->current->width;
-	int height = wlr_surface->current->height;
+	int width = wlr_surface->current.width;
+	int height = wlr_surface->current.height;
 	view_update_size(view, width, height);
 
 	double x = view->x;
@@ -233,8 +233,8 @@ static void handle_map(struct wl_listener *listener, void *data) {
 
 	view->x = surface->x;
 	view->y = surface->y;
-	view->width = surface->surface->current->width;
-	view->height = surface->surface->current->height;
+	view->width = surface->surface->current.width;
+	view->height = surface->surface->current.height;
 
 	roots_surface->surface_commit.notify = handle_surface_commit;
 	wl_signal_add(&surface->surface->events.commit,

types/data_device/wlr_drag.c

@@ -341,8 +341,8 @@ static void drag_icon_handle_surface_destroy(struct wl_listener *listener,
 static void drag_icon_handle_surface_commit(struct wlr_surface *surface,
 		void *role_data) {
 	struct wlr_drag_icon *icon = role_data;
-	icon->sx += icon->surface->current->sx;
-	icon->sy += icon->surface->current->sy;
+	icon->sx += icon->surface->current.dx;
+	icon->sy += icon->surface->current.dy;
 
 	drag_icon_set_mapped(icon, wlr_surface_has_buffer(surface));
 }