First, a screenshot of my latest level. I love the bridge model, which I bought off renderosity.com with some other high-quality, very reasonably priced artwork.
Here is another shot, showing off the water receiving sunlight shadows from the pillar :
Last time I left off with EMBM water, to get per-pixel perturbations. These look better than per-vertex, but how good they look really depends on the texture you use.
First I tried using 'refraction' or 'water' filters in various 2d art tools to generate something, but that doesn't look good, because you want just a normal map from a heightfield, not a pre-refracted texture.
I found that a simple multi-octave noise texture did the job. Here is what I'm using for the waves right now.
First, the water itself, tiled across the mesh :
Next, the height map used to generate the normal map below :
Finally, the refraction bump map itself - stretched up perpendicular to the water flow direction, to make it look like transverse waves :
Lastly, here is a cool shot with very clear water. This looks nice, but for more realism, you want to 'fog' what's under the water. I'll talk about that next time.