Examples of edited pick-whip expressionsThe following are examples of pick-whip expressions that have been altered with simple functions. These expressions are easy to create and result in sophisticated effects that would otherwise require dozens of keyframes. Animating a clock Start with two layers: an hour hand and a minute hand. Set the anchor points for the hands at the center of the clock (see Setting and animating an anchor point). Set Rotation keyframes for the hour hand; select the Rotation property for the minute hand and choose Animation > Add Expression. Drag the pick whip to the hour hand's Rotation property. The following expression appears: this_comp.layer("hour hand").rotation To make the minute hand rotate 12 times faster than the hour hand, type "*12" at the end of the expression as follows: this_comp.layer("hour hand").rotation*12 Controlling blur by its horizontal position Start with one layer that is of smaller dimensions than the composition. Set Position keyframes for the layer and then apply the Fast Blur effect. Select the Fast Blur's Blurriness property in the Timeline window and choose Animation > Add Expression. Drag the pick whip to the Position property, and the following expression appears: position[0] If the blur is too intense, cut the blur amount by one-tenth by adding "/10" to the end of the expression as follows: position[0]/10 Successive scaling up of objects Start with three layers, positioned at the location you want them to stream in from. Create Scale keyframes for the first layer. For example, make Scale = 0 at 0 seconds and Scale = 100 at 6 seconds. Select the Scale property for the second layer and choose Animation > Add Expression. Drag the pick whip to the Scale property of the first layer. The following expression appears: this_comp.layer("layer name").scale To make the second layer scale 2 seconds later than the first, add the "value_at_time" function to the end of the expression, such as: this_comp.layer("layer name").scale.value_at_time(time-2) |