implement wlr-layer-shell

libswc/compositor.c

@@ -434,6 +434,45 @@ static const struct view_impl view_impl = {
 	.move = move,
 };
 
+static void
+restack_view_for_layer(struct compositor_view *view, bool raise)
+{
+	struct compositor_view *other;
+	struct wl_list *insert_after = &compositor.views;
+	bool found_same = false;
+
+	wl_list_for_each (other, &compositor.views, link) {
+		if (other == view)
+			continue;
+
+		if (other->stack_layer > view->stack_layer) {
+			insert_after = &other->link;
+			continue;
+		}
+
+		if (other->stack_layer == view->stack_layer) {
+			found_same = true;
+			insert_after = raise ? other->link.prev : &other->link;
+			break;
+		}
+
+		insert_after = other->link.prev;
+		break;
+	}
+
+	if (!found_same && !raise && insert_after == &compositor.views) {
+		insert_after = compositor.views.prev;
+		if (insert_after == &view->link)
+			insert_after = insert_after->prev;
+	}
+
+	if (insert_after == &view->link)
+		insert_after = insert_after->prev;
+
+	wl_list_remove(&view->link);
+	wl_list_insert(insert_after, &view->link);
+}
+
 struct compositor_view *
 compositor_create_view(struct surface *surface)
 {
@@ -450,6 +489,8 @@ compositor_create_view(struct surface *surface)
 	view->window = NULL;
 	view->parent = NULL;
 	view->visible = false;
+	view->always_top = false;
+	view->stack_layer = STACK_LAYER_NORMAL;
 	view->extents.x1 = 0;
 	view->extents.y1 = 0;
 	view->extents.x2 = 0;
@@ -461,6 +502,7 @@ compositor_create_view(struct surface *surface)
 	wl_signal_init(&view->destroy_signal);
 	surface_set_view(surface, &view->base);
 	wl_list_insert(&compositor.views, &view->link);
+	restack_view_for_layer(view, true);
 
 	return view;
 }
@@ -538,6 +580,34 @@ compositor_view_hide(struct compositor_view *view)
 	}
 }
 
+void
+raise_window_top(struct compositor_view *view)
+{
+	view->stack_layer = STACK_LAYER_OVERLAY;
+	restack_view_for_layer(view, true);
+	damage_view(view);
+	update(&view->base);
+}
+
+void
+compositor_view_set_stack_layer(struct compositor_view *view, uint32_t layer, bool raise)
+{
+	if (view->stack_layer == layer) {
+		if (raise) {
+			restack_view_for_layer(view, true);
+			damage_view(view);
+			update(&view->base);
+		}
+		return;
+	}
+
+	damage_view(view);
+	view->stack_layer = layer;
+	restack_view_for_layer(view, raise);
+	damage_view(view);
+	update(&view->base);
+}
+
 void
 compositor_view_set_border_width(struct compositor_view *view, uint32_t width)
 {

libswc/compositor.h

@@ -55,6 +55,8 @@ struct compositor_view {
 
 	/* Whether or not the view is visible (mapped). */
 	bool visible;
+	bool always_top;
+	uint32_t stack_layer;
 
 	/* The box that the surface covers (including it's border). */
 	pixman_box32_t extents;
@@ -87,6 +89,18 @@ void compositor_view_set_parent(struct compositor_view *view, struct compositor_
 void compositor_view_show(struct compositor_view *view);
 void compositor_view_hide(struct compositor_view *view);
 
+void raise_window_top(struct compositor_view *view);
+
+enum compositor_stack_layer {
+	STACK_LAYER_BACKGROUND = 0,
+	STACK_LAYER_BOTTOM = 1,
+	STACK_LAYER_NORMAL = 2,
+	STACK_LAYER_TOP = 3,
+	STACK_LAYER_OVERLAY = 4,
+};
+
+void compositor_view_set_stack_layer(struct compositor_view *view, uint32_t layer, bool raise);
+
 void compositor_view_set_border_color(struct compositor_view *view, uint32_t color);
 void compositor_view_set_border_width(struct compositor_view *view, uint32_t width);
 

libswc/internal.h

@@ -47,6 +47,7 @@ struct swc {
 	struct swc_drm *const drm;
 	struct wl_global *data_device_manager;
 	struct wl_global *kde_decoration_manager;
+	struct wl_global *layer_shell;
 	struct wl_global *panel_manager;
 	struct wl_global *shell;
 	struct wl_global *subcompositor;