As a wave nears the shore its bottom begins to be effected by that in several ways. The first is that the orb of energy I described last night is lifted up so that more of it becomes exposed above the surface of the water. The wave "grows" in size because more of it is revealed by the lower level of the water about it's feet.
The second effect from the shallow water is s slowing of the bottom of the moving orb. This causes that orb to lean forward at a greater angle. As the whole system grows unstable the water from the back of the wave beginning to rush over the front. Below is a wave doing that. .
The cascade of water over the top has begun, when it hits the face of the wave it explodes into foam. Here's what that looks like close up.
The back of the wave is visible in this picture, below that the water becomes more aerated and then turns to foam. Below is a diagram of the surface of the water. As I explained last night, most of this water is a skin over the forces below, being stretched more than moved by the force of the rolling orb hidden beneath it. Oh, do do da day!