compositor: add a doc note for weston_view::parent_view

It is used by sub-surfaces only, for fetching the root view's
weston_layer.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-By: Giulio Camuffo <giuliocamuffo@gmail.com>

diff --git a/src/compositor.h b/src/compositor.h
index 47b6036..a90ede6 100644 (file)
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -759,6 +759,8 @@ struct weston_view {
        struct wl_list link;
        struct weston_layer_entry layer_link;
        struct weston_plane *plane;
+
+       /* For weston_layer inheritance from another view */
        struct weston_view *parent_view;
 
        pixman_region32_t clip;          /* See weston_view_damage_below() */