AABB tree: document size, bbox and empty of the tree

note: we could rename root_bbox as simply bbox

AABB_tree/doc_tex/AABB_tree_ref/AABB_tree.tex

@@ -61,6 +61,15 @@ The class \ccRefName\ is a static data structure for efficient intersection and
 \ccMethod{void clear(void);}
 {Clears the AABB tree. }
 
+\ccMethod{Bounding_box root_bbox();}
+{Returns the root axis-aligned bounding box of the whole tree. }
+
+\ccMethod{size_t size();}
+{Returns the number of primitives in the tree. }
+
+\ccMethod{bool empty();}
+{Returns \ccc{true} iff tree contains no primitive. }
+
 % INTERSECTION TESTS
 \ccHeading{Intersection Tests}
 

AABB_tree/include/CGAL/AABB_tree.h

@@ -120,8 +120,6 @@ namespace CGAL {
         Point_and_primitive closest_point_and_primitive(const Point& q, const Point& hint) const;
         Point_and_primitive closest_point_and_primitive(const Point& q) const;
 
-        //////////////////////////////////////////////
-        //TODO: document this
         Bounding_box root_bbox() const { return m_p_root->bounding_box(); }
         bool is_empty() const { return m_data.empty(); }
         size_t size() const { return m_data.size(); }