Apple Shake 4 - Manual (Page 815)

Chapter 27 Warping and Morphing Images 815
Shake uses the seed value as the basis for generating a random value. Using the same
seed value results in the same random value being generated, so that your image
doesn’t change every time you re-render. Use a single value for a static result, or use
the expression “time” to create a pattern of random values that changes over time.
For more information on using random numbers in expressions, see “ Reference Tables
for Functions, Variables, and Expressions ” on page 941.
xAmplitude, yAmplitude
The amount of randomization in pixel distance.
xOffset, yOffset
An offset to the random pattern.
Turbulate
The Turbulate node is similar to the Randomize node, except that it passes a continuous
field of noise over the image, rather than just randomly stirring the pixels around. This
is a processor-intensive node.
Parameters
This node displays the following controls in the Parameters tab:
overSampling
The actual number of samples per pixel equals this number squared. For better
antialiasing, increase the number.
detail
The amount of fractal detail. The higher the number, the more iterations of fractal
noise. This can be very processor-intensive.
xNoiseScale, yNoiseScale
The scale of the waves.
xAmplitude, yAmplitude
The amount of randomization in pixel distance.
xOffset, yOffset
Lets you offset the effect on the image.
seed
When Shake generates a random pattern of values, you need to make sure for
purposes of compositing that you can recreate the same random pattern a second
time. In other words, you want to be able to create different random patterns,
evaluating each one until you find the one that works best, but then you don’t want
that particular random pattern to change again.