I have an array that contains the state of certain cells. It looks like this.

Code:
   5                  
   4                  
   3   *   *   *   *      
y  2   *   *   *   *      
   1   *   *   *   *      
   0   *   *   *   *      
       0   1   2   3   4   5
            x
I am trying to rotate the array using this formula:

x' = (x * Cos deg.) - (y * Sin deg.)
y' = (x * Sin deg.) + y * (Cos deg.)

The code (VB .Net) uses Math.Cos & Math.Sin which produce double results. I think my problem happens when I convert the results to integer. Am I missing something?