diff --git a/desktop-shell/shell.c b/desktop-shell/shell.c
index a8fb451f..53e0071a 100644
--- a/desktop-shell/shell.c
+++ b/desktop-shell/shell.c
@@ -344,7 +344,7 @@ get_panel_size(struct desktop_shell *shell,
 				     view->surface);
 	b = weston_coord_surface_to_global(view, tmp_s);
 
-	a.c = weston_coord_sub(b.c, a.c);
+	a = weston_coord_global_sub(b, a);
 	*width = a.c.x;
 	*height = a.c.y;
 }
@@ -2498,10 +2498,10 @@ desktop_surface_committed(struct weston_desktop_surface *desktop_surface,
 		from_g = weston_coord_surface_to_global(view, from_s);
 		to_g = weston_coord_surface_to_global(view, to_s);
 
-		offset.c = weston_coord_sub(to_g.c, from_g.c);
-		pos.c = weston_coord_add(
-			weston_view_get_pos_offset_global(view).c,
-			offset.c);
+		offset = weston_coord_global_sub(to_g, from_g);
+		pos = weston_coord_global_add(
+			weston_view_get_pos_offset_global(view),
+			offset);
 
 		weston_view_set_position(shsurf->view, pos);
 	}
diff --git a/include/libweston/matrix.h b/include/libweston/matrix.h
index 7b4adee1..2bee61fa 100644
--- a/include/libweston/matrix.h
+++ b/include/libweston/matrix.h
@@ -160,12 +160,26 @@ weston_coord_add(struct weston_coord a, struct weston_coord b)
 	return weston_coord(a.x + b.x, a.y + b.y);
 }
 
+static inline struct weston_coord_global __attribute__ ((warn_unused_result))
+weston_coord_global_add(struct weston_coord_global a,
+			struct weston_coord_global b)
+{
+	return (struct weston_coord_global){ .c = weston_coord_add(a.c, b.c) };
+}
+
 static inline struct weston_coord __attribute__ ((warn_unused_result))
 weston_coord_sub(struct weston_coord a, struct weston_coord b)
 {
 	return weston_coord(a.x - b.x, a.y - b.y);
 }
 
+static inline struct weston_coord_global __attribute__ ((warn_unused_result))
+weston_coord_global_sub(struct weston_coord_global a,
+			struct weston_coord_global b)
+{
+	return (struct weston_coord_global){ .c = weston_coord_sub(a.c, b.c) };
+}
+
 static inline struct weston_coord __attribute__ ((warn_unused_result))
 weston_coord_truncate(struct weston_coord in)
 {
diff --git a/kiosk-shell/kiosk-shell.c b/kiosk-shell/kiosk-shell.c
index 14bb78a5..960c4e91 100644
--- a/kiosk-shell/kiosk-shell.c
+++ b/kiosk-shell/kiosk-shell.c
@@ -820,10 +820,10 @@ desktop_surface_committed(struct weston_desktop_surface *desktop_surface,
 
 		from_g = weston_coord_surface_to_global(shsurf->view, from_s);
 		to_g = weston_coord_surface_to_global(shsurf->view, to_s);
-		offset.c = weston_coord_sub(to_g.c, from_g.c);
-		pos.c = weston_coord_add(
-			weston_view_get_pos_offset_global(shsurf->view).c,
-			offset.c);
+		offset = weston_coord_global_sub(to_g, from_g);
+		pos = weston_coord_global_add(
+			weston_view_get_pos_offset_global(shsurf->view),
+			offset);
 
 		weston_view_set_position(shsurf->view, pos);
 		weston_view_update_transform(shsurf->view);
diff --git a/libweston/compositor.c b/libweston/compositor.c
index c241ee35..b70878b9 100644
--- a/libweston/compositor.c
+++ b/libweston/compositor.c
@@ -6496,7 +6496,7 @@ weston_output_set_position(struct weston_output *output,
 		return;
 	}
 
-	output->move.c = weston_coord_sub(pos.c, output->pos.c);
+	output->move = weston_coord_global_sub(pos, output->pos);
 
 	if (output->move.c.x == 0 && output->move.c.y == 0)
 		return;