creating sea water weaves

Hi all,

I would like to create some weaves (seen from the front view).
I have started out using a paint opperator, then I created a box
and added some more points to it. I think i need that for the sine
to work correctly. Or having 4 controle point would do the trick?

I think i need a math-expression so I adjusted the sine..
but do i need to add math-expresion to the controle_points?
i have tried few things but can get the sea bed water effect
im looking for :-(

any advice?