Animating with Generators
Parameter evolution over time
In order to animate a parameter/make it evolve, you can use:
- A Generator, such as Current Time, Noise, Expression, or Random
- Modifiers, such as Animator
- Keyframes
We will go over Generators, as the Animator Modifier and Keyframes will be described in separate sections.
Let's start with a simple Circle in a new composition and look over its Position param, in the Transform section:
By clicking on the Generator slot and scrolling in the lower right box of the Quad menu, we can add a Random Generator.
Now the parameter values are grayed out which indicates that they can no longer be edited manually, as the Generator is overwriting the original values and is taking complete control of the parameter.
However, these original values are not lost because they are embedded in the parameter. If the Generator is disconnected or deleted, this data will reappear and be available to edit again.
Set the Minimum value to -250, the Maximum to 250, switch Varying to Time, and press Play in the Viewer.
Two random, separate values are defined for X and Y at each frame. The circle then "jumps" from one position to the other. To know more about the Random Generator, please refer to this section. Once these values are generated, you can modify them by adding Modifiers. You can do this by clicking on the button with a scientific flask icon, just next to the Generator button.
For more information about the concept of Modifiers, please refer to this section.
Generators can control other Generators
In the above example, a Random Generator was added onto the Position parameter and took control; but, this Generator also has its own parameters with a Generator slot and a button to add Modifiers. So it's also possible to control Generators with other Generators, and so on without limitations.
Automatic addition of Generators
Some actions in Autograph will automatically add a Generator to a parameter. For example, the "+" button on top of the stack will automatically create layers with Image Generators like a gradient, circle, or 2Dnoise.
Numerical Generators can also be added automatically, such as Follow path, which allows you to constrain layer movement on a curve. The Curve tool in the Viewer has an option to add both a curve and the Generator that allows the layer to follow it.
To know more about Follow path, please refer to this Generator documentation.