Specifications

Chapter 12 Tasks and Expressions 213
Using Numeric Operators In some cases, you may want to combine multiple values. For instance, in the
previous example, you may change the expression so that the modulation
wheel modulates the value of the cue’s Opacity tween track by entering the
following expression into its formula dialog box:
This expression combines the value of the ModWheel input with the value
coming from the tween track itself by using the TweenValue identifier, which
provides the enclosing tween track’s current value. Since both values are in the
range 0 through 1, multiplying them in this way will work as desired.
Alternatively, you may want to combine the two values so that the opacity can
be controlled by either the tween track or the modulation wheel. This can be
accomplished by changing the formula to
TweenValue + ModWheel
Now the resulting image will appear on stage if the tween track or the external
input says so. Note that if both the tween track and the input are at their
maximum value, the result of the expression will be 2. However, the opacity
Enter an expression for a tween
track by clicking its formula
button (see page 202).