How do I clip fish coming out of water?

Hi,

I've got a nice water graphic, with the wave effect applied.

I'd like to have fish jumping out. For this to look good, they'd need to look like they were coming out from behind the water that's between them and the viewer - in other words the image would need to be clipped by the waves.

If I create another wave graphic, then they could only come out of that one horizontal point.

How do I make fish look like they're coming out of the water?

In other words, from this graphic:

<img src="https://dl.dropboxusercontent.com/u/17914213/fish.png" border="0" />

I want to do this (notice the clipping on the lower part):

<img src="https://dl.dropboxusercontent.com/u/17914213/fish_out_of_water.png" border="0" />

Easiest way would be to use three layers, with two images for the waves: one in the foreground and one in the background. Place the fish on a layer between the two waves.

You can try blend modes too: scirra.com/manual/146/effects

I used the source out (or destination out I don't remember) to make the illusion of a character going through a door, with a empty sprite filled with color.

I've looked through the blend modes and don't see how they can be made to clip an object.

In the end, it is/was easier to split the graphics up and have them inhabit different Z-layers. But, that limits where the fish can come out of the water.