In real life, waves (as swells) travel as very shallow sine undulations. As they approach shallow water, they compress and steepen, as well as refract to match the bathymetry. So we are to this point so far, just without the compression. See the attached file below, though its still not accurate in the fact that the waves in this file actually "die off" in deep water. I am going to work on this next.
As swells get to even shallower water, they steepen further, with the leading edge of the wave front becoming steeper than the trailing edge forming a cusp like appearance, similar to sand dunes. I'm not sure how we can pull this off yet in TG2, but its very likely possible with extensive tests.
Of course, when the wave front's steepness becomes too great, it will break. Depending upon how fast this happens (which depends on the bathymetry's slope angle), it will roll, plunge with a tube, or spill. We can likely simulate the rolling and spilling, but the plunging will likely require serious work beyond what any of us have accomplished yet, and even require a 3D model to pull off.
Anyway, when waves break, the chaos generates whitewater. Waves break due to many factors, including wind chop "white caps", breaking waves over a shoal, or splashes due to blunt object impacts (like boats, pier posts, asteroids, etc). When the whitewater subsides, it leaves "soup", which is a stringy/matty looking weave of bubbles.
I've been trying to simulate "soup" near the coast, but unable to get it to fade off into deep water at this time. I have been able to get it to appear all over the entire water surface, but this is unrealistic unless the water is mega choppy.