scene: Add layer_shell_v1 helper

This helper behaves similar to the xdg_shell helper, and additionally
provides a little assistance for positioning and exclusive_zone
management.

1 files changed, 38 insertions, 0 deletions

diff --git a/include/wlr/types/wlr_scene.h b/include/wlr/types/wlr_scene.h
index a77eb6c2..86775399 100644
--- a/include/wlr/types/wlr_scene.h
+++ b/include/wlr/types/wlr_scene.h
@@ -26,6 +26,7 @@
 struct wlr_output;
 struct wlr_output_layout;
 struct wlr_xdg_surface;
+struct wlr_layer_surface_v1;
 
 enum wlr_scene_node_type {
 	WLR_SCENE_NODE_ROOT,
@@ -136,6 +137,19 @@ struct wlr_scene_output {
 	bool prev_scanout;
 };
 
+/** A layer shell scene helper */
+struct wlr_scene_layer_surface_v1 {
+	struct wlr_scene_node *node;
+	struct wlr_layer_surface_v1 *layer_surface;
+
+	// private state
+
+	struct wl_listener tree_destroy;
+	struct wl_listener layer_surface_destroy;
+	struct wl_listener layer_surface_map;
+	struct wl_listener layer_surface_unmap;
+};
+
 typedef void (*wlr_scene_node_iterator_func_t)(struct wlr_scene_node *node,
 	int sx, int sy, void *data);
 
@@ -354,4 +368,28 @@ struct wlr_scene_node *wlr_scene_subsurface_tree_create(
 struct wlr_scene_node *wlr_scene_xdg_surface_create(
 	struct wlr_scene_node *parent, struct wlr_xdg_surface *xdg_surface);
 
+/**
+ * Add a node displaying a layer_surface_v1 and all of its sub-surfaces to the
+ * scene-graph.
+ *
+ * The origin of the returned scene-graph node will match the top-left corner
+ * of the layer surface.
+ */
+struct wlr_scene_layer_surface_v1 *wlr_scene_layer_surface_v1_create(
+	struct wlr_scene_node *parent, struct wlr_layer_surface_v1 *layer_surface);
+
+/**
+ * Configure a layer_surface_v1, position its scene node in accordance to its
+ * current state, and update the remaining usable area.
+ *
+ * full_area represents the entire area that may be used by the layer surface
+ * if its exclusive_zone is -1, and is usually the output dimensions.
+ * usable_area represents what remains of full_area that can be used if
+ * exclusive_zone is >= 0. usable_area is updated if the surface has a positive
+ * exclusive_zone, so that it can be used for the next layer surface.
+ */
+void wlr_scene_layer_surface_v1_configure(
+	struct wlr_scene_layer_surface_v1 *scene_layer_surface,
+	const struct wlr_box *full_area, struct wlr_box *usable_area);
+
 #endif