we have to choose on purpose one area to show as more land types as possible. 
For ex., (0,63,0)---(0,130,0)
           ..         ..
         (7,63,0)---(7,130,0)
 this rectangular has been chosen to shown because it has contained almost all 7 types of land use.

the problem is : the transition rule is still too simple.

If you like, you could help to make it more complex.

