Animate with generators
Parameter evolution over time
Now that we know more about parameters, let's see how to animate them.
In order to make a parameter evolve, you can use:
- A Generator, such as Current Time, Noise, Expression or Random
- Modifiers, such as Animator
Animator and Keyframes will be described in dedicated sections, so we are going to focus on Generators first.
Let's start with a simple Circle in a new composition and inspect it's Position param, in the Transform section:
By clicking on the Generator slot, we can add a Random generator by scrolling in the lower right box of the Quad menu.
The parameter values are now grayed out, indicating that they can no longer be edited manually, as the generator overwrites the original values and takes 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 will 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 values are defined for X and Y independently 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
You have just added a Random generator on the Position parameter, which has just taken control; but, you notice that this generator also has parameters with a generator slot and a button to add modifiers. It is therefore 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 contains an option to add both the curve and the generator that allows the layer to follow it.
To know more about Follow path, please refer to this generator documentation.