Basic Relationships: Set-Driven Keys
A favorite feature for character riggers is the set-driven key (SDK). A set-driven key establishes a relationship for objects that lets you create controls that drive certain features of a character or an object in a scene.
Before you can use an SDK, you must create extra attributes and attach them to a character’s top node. These new attributes drive part of the character’s animation. The term character is used broadly here. For example, you can set up a vehicle so that an SDK turns its wheels.
Let’s start with a simple SDK relationship between two objects. You’ll create a relationship between a ball and a cone. As the ball moves up in the Y-axis, the cone spins in the X-axis. As the ball descends, the cone ...