Water is more complex than one would think. There's water appearance (both surface and underwater), water physics, appearance of the stuff that is above the water surface, watched from under water etc.
I think it depends on the way you want to use it. Personally I use a simple underwater mode in my engine (reduced gravity). The sinus distortion of the screen is even very unrealistic, but I like it :) Oh yeah, and bubbles - they are very substancial.
Realistc water physics sound very hard to me because water with all it's reactions could be compared with an ordinary physics engine where every molecule is an individual entity. So I guess it must be simplified drasticly.
I think it depends on the way you want to use it. Personally I use a simple underwater mode in my engine (reduced gravity). The sinus distortion of the screen is even very unrealistic, but I like it :) Oh yeah, and bubbles - they are very substancial.
Realistc water physics sound very hard to me because water with all it's reactions could be compared with an ordinary physics engine where every molecule is an individual entity. So I guess it must be simplified drasticly.