Game Development Reference
The Foam Effect
At the most basic level, the Foam effect creates bubbles. If you're
like me, you've never ever needed bubbles in a professional setting
before. I'm sure it can come in handy often—for bathtub scenes
for animations on TV shows for kids, visual fl atulence jokes, bub-
bling soda, or boiling cauldrons.
There is a limit to how helpful bubbles can be. But the Foam
effect is far more important and useful than for just creating
bubbles. The Foam effect is one of my favorites in After Effects
because of how intuitive and versatile it is. We can use it to
make snow or a multitude of other effects because it allows us to
replace the bubbles with textures of our own. It is more power-
ful than any of the other particle generators in After Effects, after
Particle Playground. But Foam renders far more quickly and is
much easier to set up than Particle Playground. I can honestly
say that the Foam effect is my natural particle effect of choice in
Open the Foam.aep project from the Chapter 16 folder of the
exercise fi les. This project contains a few comps because I really
want to convey how versatile this effect can be. We'll start out in
the Using Foam comp, which demonstrates the Foam effect in its
native habitat (as foamy bubbles).
The Using Foam comp contains a shot of a little kid in the
bathtub, as well as a solid layer (Fig. 16.25).
The Foam effect completely replaces the content of the layer
to which it's applied, so it's usually a good idea to apply this to a
solid. So, apply the Foam effect to the blue solid layer. The good
news is that Foam autoanimates. Preview this comp to watch
bubbles fl y out all over the place. The bad news here is that the
Figure 16.25 The kid in the tub
layer in the Using Foam comp.