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Using Motion Math (PB only)
Using Motion Math (PB only)
Use Motion Math to write and run scripts that use a special language and mathematical
equations to generate keyframes. Motion Math can create complex changes for any
property, using scripts included with the Production Bundle or scripts that you write.
Motion Math scripts create motion or effects by applying mathematical equations to
specified layers, properties, and other values and then automatically generating
keyframes. Even a basic equation can simplify the creation of complex effects that might
otherwise require painstakingly specifying individual keyframes. More complex manipula-
tions of keyframes using Motion Math requires a basic understanding of how formulas
work, how approximate values will be derived from the formula, and how these values will
affect the keyframes to which they are assigned.
Scripts are written in the Motion Math language, a simplified version of the widely used
C programming language. The Motion Math language provides these basic programming
tools: assignments, if statements, loops, and numerous math functions, including those
for trigonometry, the natural logarithm, and vectors.
Using Expressions instead of Motion Math (PB only)
Many of the effects created using Motion Math can now be created using Expressions. For
example, instead of running the Copy Values script to link different properties, simply click
the Expression's pick whip, and drag it from one property to another. For information on
expressions, see "Using expressions" on page 244.
For some effects, however, it may be easier to use Motion Math. For example, to
synchronize audio and property changes, you may find it more efficient to use the Motion
Math script Layeraud.mm than to write your own expression. Also, the Scale All Layers
script makes it easy to automatically scale and position objects correctly, whereas to
replicate the effect using expressions requires two separate expressions for each layer.
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Index
Index
Using Motion Math (PB only)
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