Here is the foam texture I have been using in my testing. It works even better if you warp it by the waves scalar multiplied by whatever amplitude looks good. Use it was breakup for a surface layer masked by the smooth wake mask.
I guess this works, though not as accurately as I'd want. Obviously, it won't work if you're backing up into the floor of the scalar.
Edit this was supposed to be a reply to another topic. Oi.
Cool! Thanks, Jordan!