Duplicating an Animation by Using the Pick Whip
Now, you need to lighten the view through the window. To do this, you'll use the pick whip to duplicate the animation you just created. You can use the pick whip to create expressions that link the values of one property or effect to another.
- Press the Home key to go to the beginning of the time ruler.
- Select the Window Lit layer and press T to reveal its Opacity property.
- Alt-click (Mac OS: Option-click) the Opacity stopwatch for the Window Lit layer to add an expression for the default Opacity value, 100%. The words transform.opacity appear in the time ruler for the Window Lit layer (see Figure 9).
- With the transform.opacity expression selected in the time ruler, click the pick whip icon on the Window Lit Expression: Opacity line and drag it to the Opacity property name in the Background Lit layer (see Figure 10). When you release the mouse, the pick whip snaps, and the expression in the Window Lit layer's time ruler now reads as follows:
thisComp. layer("Background Lit").transform.opacity
This means that the Opacity value for the Background Lit layer (0%) replaces the previous Opacity value (100%) for the Window Lit layer.
- Drag the current-time indicator from 0:00 to 5:00. Notice that the Opacity values for the two layers match.
- Press the Home key and then the spacebar to preview the animation again. Notice that the sky outside the window lightens as the room inside the window does.
- Press the spacebar to stop playback.
- Hide the Window Lit and Background Lit layers' properties to keep the Timeline panel tidy for your next task.
- Choose File > Save to save your project.