Waves break on an action line, action lines are adjacent and cross the force lines of wave movement.
The four steps of a wave. The face, the fall, the explosion and the
after ripples.

Lines off force go in the direction of the wave movement.
In this case the force lines are moving around the reef and rocks.

The fan brush can do a lot more then just blend and make grass strokes.

Next, Painting with these techniques.
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