add wlr_layer_surface_surface_at

Adds wlr_layer_surface_surface_at, this is consistent with the other
shell implementations, and simplifies handling in compositors.

include/wlr/types/wlr_layer_shell.h

@@ -113,4 +113,12 @@ struct wlr_layer_surface *wlr_layer_surface_from_wlr_surface(
 void wlr_layer_surface_for_each_surface(struct wlr_layer_surface *surface,
 		wlr_surface_iterator_func_t iterator, void *user_data);
 
+/**
+ * Find a surface within this layer-surface tree at the given surface-local
+ * coordinates. Returns the surface and coordinates in the leaf surface
+ * coordinate system or NULL if no surface is found at that location.
+ */
+struct wlr_surface *wlr_layer_surface_surface_at(
+		struct wlr_layer_surface *surface, double sx, double sy,
+		double *sub_x, double *sub_y);
 #endif

rootston/desktop.c

@@ -641,30 +641,17 @@ static struct wlr_surface *layer_surface_at(struct roots_output *output,
 		struct wl_list *layer, double ox, double oy, double *sx, double *sy) {
 	struct roots_layer_surface *roots_surface;
 	wl_list_for_each_reverse(roots_surface, layer, link) {
-		struct wlr_surface *wlr_surface;
+		double _sx = ox - roots_surface->geo.x;
-		double _sx, _sy;
+		double _sy = oy - roots_surface->geo.y;
-		struct wlr_xdg_popup *popup;
+
-		wl_list_for_each(popup, &roots_surface->layer_surface->popups, link) {
+		struct wlr_surface *sub = wlr_layer_surface_surface_at(
-			wlr_surface = popup->base->surface;
+			roots_surface->layer_surface, _sx, _sy, sx, sy);
-			 _sx = ox - roots_surface->geo.x - popup->geometry.x;
+
-			 _sy = oy - roots_surface->geo.y - popup->geometry.y;
+		if (sub) {
-			if (wlr_surface_point_accepts_input(wlr_surface, _sx, _sy)) {
+			return sub;
-				*sx = _sx;
-				*sy = _sy;
-				return wlr_surface;
-			}
-			// TODO: popups can have popups
-		}
-		// TODO: Test subsurfaces
-		wlr_surface = roots_surface->layer_surface->surface;
-		 _sx = ox - roots_surface->geo.x;
-		 _sy = oy - roots_surface->geo.y;
-		if (wlr_surface_point_accepts_input(wlr_surface, _sx, _sy)) {
-			*sx = _sx;
-			*sy = _sy;
-			return wlr_surface;
 		}
 	}
+
 	return NULL;
 }
 

types/wlr_layer_shell.c

@@ -531,3 +531,25 @@ void wlr_layer_surface_for_each_surface(struct wlr_layer_surface *surface,
 		wlr_surface_iterator_func_t iterator, void *user_data) {
 	layer_surface_for_each_surface(surface, 0, 0, iterator, user_data);
 }
+
+struct wlr_surface *wlr_layer_surface_surface_at(
+		struct wlr_layer_surface *surface, double sx, double sy,
+		double *sub_x, double *sub_y) {
+	struct wlr_xdg_popup *popup_state;
+	wl_list_for_each(popup_state, &surface->popups, link) {
+		struct wlr_xdg_surface *popup = popup_state->base;
+
+		double popup_sx = popup_state->geometry.x - popup->geometry.x;
+		double popup_sy = popup_state->geometry.y - popup->geometry.y;
+
+		struct wlr_surface *sub = wlr_xdg_surface_surface_at(popup,
+			sx - popup_sx,
+			sy - popup_sy,
+			sub_x, sub_y);
+		if (sub != NULL) {
+			return sub;
+		}
+	}
+
+	return wlr_surface_surface_at(surface->surface, sx, sy, sub_x, sub_y);
+}