how to determine the bezier surface' control point

i define the point array as
ctrlPoint[4][m][3]or ctrlPoint[n][4][3],there is no problem,but i define the array as ctrlPoint[5][5][3],the picture are not right,i want to use bezier suface to express terrain,there are many control points,so i want to know the method of define the terrain control point,who will help me?3x!

bezier pathes are made with 16 control points (4x4). You might want to have a look for hermite curves instead as they are easier to join up, and therefore make it slightly easier to do terrain. As for the points, they could be generated using fractals.