Periodic

Periodic mode adds a variation to layers or parameters, based on a periodic function. This oscillating function is similar to the generally better known Sine or Cosine functions.

Layer Time Offset

When selecting Periodic mode from the list, you will see a Frequency parameter that is set to 0.5 by default:

In the following example, we select a group of about 20 layers and start to time offset the one at the top of the stack:

The distance covered by the mouse defines a variation applied to every other layer, in one direction and then another.

We'll do the same operation, this time setting Frequency to 0.1:

You can see that the lower frequency produces a much more extended kind of wave. The layer you click on will cover 100% of the distance covered by the mouse, but the other layers will be weighted by a periodic function.

Signed Distribution

By default, you can see that the layers move to the left as well as to the right. This is because a periodic function is sometimes positive, sometimes negative.

By unchecking the Signed option, this function will no longer evolve between -1.0 and 1.0, but between 0.0 and 1.0.

This way, you can move your mouse to the right while ensuring that no layer is time offset before the first frame of the composition.

Quickly Change the Frequency Value, Live

It is difficult to predict the appearance of the wave in advance. That's why the Frequency value can be modified live:

While moving layers and without releasing the mouse button:

• Pressing the Up key will increase the Frequency value by 0.01
• Pressing the Down key will decrease the Frequency value by 0.01

Distribution Across Other Parameters

Periodic mode can be used to apply these variations over several parameters that are the same type.

In the example below, we click on the layer at the top of the stack, which will define it as the active layer, then press the Shift key before clicking on the lowest layer in the stack.

With this set of layers selected, we can modify the Position.Y parameter of the active layer, as displayed in the Inspector, in the Properties section.

The distance traveled by the active layer is reported on the other parameters according to a periodic function:

Changing the Active Layer

To define a new active layer, simply press the Ctrl/Cmd key, click on a layer to deselect it, then click again while holding Ctrl/Cmd to reselect it.

Changing the Position.Y value again will have a completely different effect.