William Marler shows how you can link the rotation property of one object to the colour of one or more other objects through the use of expression in After Effects.
In this tutorial, you’ll learn how to use expressions to link the rotation of one object to the color of multiple othersWilliam Marler – AEtuts.com
Using Expressions in After Effects, you are able to build the project in a way that can be edited to be flexible for different project scenarios. William walks through the basics of defining values in After Effects to make the code much neater visually. Understanding and using the After Effects Linear Interpolation expression is key in getting the right setup here.
Having some prior experience with expressions in After Effects will be useful, but isn’t essential for following along with this tutorial. Check out the tutorial for Changing Color in After Effects Based on an Object’s Rotation here.