8. Quadtrees and Octrees.   

The following is covered:

      Introduction  
      Quadtrees  
      Constructing a Quadtree  
      Retrieving a Quadtree image  
      Advantages of Quadtrees  
      Disadvantages of Quadtrees  
      Octrees  
      How Octrees work  
      Advantages of Octrees  
      Disadvantages of Octrees  
      What Octrees are used for  
      Source code  
      References