Game Development Reference
Open up the Smear.aep project from the Chapter 7 folder. This
contains a comp with a rocket image. We'll be using Smear to dis-
tort the trail of fi re coming out of the exhaust of the rocket. I've
already created two masks for you on this layer: an elliptical mask
that will be the source mask and a rectangular mask that we'll use
as a boundary mask (Fig. 7.78).
Figure 7.78 The two masks on
the Rocket layer in the Rocket
Next apply the Smear effect. Before you worry about what's
going on, fi rst change the Source Mask value to Mask 1, and the
Boundary Mask value to Mask 2.
The Smear effect allows you to deform the portion of the layer
inside the source mask in three basic ways: moving, scaling, and
rotating. When you fi rst apply the Smear effect, you might have
noticed an additional shape that matches the shape of the source
mask. This area is like a smear controller, as the pixels in the
source mask will be pulled towards the pixels in the smear con-
troller. The position of this smear controller can be adjusted by
the Mask Offset property (Fig. 7.79).
Use Mask Offset to move the pixels in the source mask. Use
Mask Rotation to rotate the pixels in the source mask. And use
Mask Scale to adjust the scale of the pixels in the source mask.
Notice, however, that these properties only work to the degree
that you've increased the Percent value. Think of the Percent
value as the master distortion control in this effect. The Elasticity
and Interpolation Method parameters (which we covered in the
Reshape effect, earlier in this chapter) are also here to help you
customize your distortions (Fig. 7.80).