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 of 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.
Subscribe to 'Painting on Location' Forum for artists, Questions and Answers.
Painting on Location Join PoL Forum from waves
Questions about waves? Join the Painting on Location Forum
Comments?
Don Jusko