how do you make a loop run in reverse?

[rahulreddy24 at hotmail.com]

So i have a set of for loops that create this :

***************************************
***   ***   ***   ***   ***   ***   ***   
***   ***   ***   ***   ***   ***   ***   
   ***   ***   ***   ***   ***   ***   ***
   ***   ***   ***   ***   ***   ***   ***
***************************************
                  
                 *
                ***
               *****
              *******
             *********

but i want to nest all the loops under one BIG loop that'll run in reverse to make this:

***************************************
***   ***   ***   ***   ***   ***   ***   
***   ***   ***   ***   ***   ***   ***   
   ***   ***   ***   ***   ***   ***   ***
   ***   ***   ***   ***   ***   ***   ***
***************************************
                  
                 *
                ***
               *****
              *******
             *********
              *******
               *****
                ***
                 *
***************************************
   ***   ***   ***   ***   ***   ***   ***
   ***   ***   ***   ***   ***   ***   ***
***   ***   ***   ***   ***   ***   ***   
***   ***   ***   ***   ***   ***   ***   
***************************************

Is this possible?