Optimize raycast performance (#15233)

by skipping nodes not on the ray with selection boxes smaller than 1x1x1 early on

src/nodedef.h

@@ -425,6 +425,8 @@ struct ContentFeatures
 	NodeBox node_box;
 	NodeBox selection_box;
 	NodeBox collision_box;
+	//! Whether any selection box extent is > BS/2.
+	bool has_big_selection_box;
 
 	// --- SOUND PROPERTIES ---
 
@@ -774,6 +776,9 @@ private:
 	 */
 	void fixSelectionBoxIntUnion();
 
+	//! Calculates ContentFeatures::&has_big_selection_box
+	void calcBigSelectionBox(content_t id, const ContentFeatures &def);
+
 	//! Features indexed by ID.
 	std::vector<ContentFeatures> m_content_features;