Animation menu > Constraints > Orientation Constraint
An Orientation constraint causes an objectÆs orientation to follow the orientation of an object or averaged orientation of several objects.
An Orientation-constrained object can be any rotatable object. When constrained, it will inherit its rotation from a target object. Once constrained, you can not rotate the object manually, you may move or scale the object as long as its not constrained in a manner that affects the objectÆs position or scale controller.
The target object can be any type of object. The rotation of a target object drives the constrained object. Targets can be animated using any of the standard translation, rotation, and scale tools.
A constrained object can be influenced by several target objects. When using multiple targets, each target has a weight value that defines the degree by which it influences the constrained object, relative to other targets.
Using Weight is meaningful (and available) only with multiple targets. A value of 0 means the target has no influence. Any value greater than 0 causes the target to influence the constrained object relative to other targets' Weight settings. For example, a target with a Weight value of 80 will have twice the influence of a target with a Weight value of 40.
Procedures
To assign an Orientation constraint:
Select the object you want to constrain.
Choose Animation menu > Constraints > Orientation Constraint.
Select target object.
To access the Orientation constraintÆs parameters through the Motion panel:
Select the Orientation-constrained object.
On the Motion panel > Rotation list, double-click Orientation Controller.
The Orientation constraint parameters are located on the Orientation Constraint rollout.
To edit weight values:
Select the constrained object.
Open the Motion panel > Orientation Constraint rollout.
Click a target from the list.
Use the Weight spinner or enter a numerical value to set the weight value.
To animate weight values:
Select the constrained object.
Open the Motion panel > Orientation Constraint rollout, and choose a target from the list.
Turn on the Animate button.
Use the Weight spinner or enter a numerical value to set the weight value.
Interface
Once you assign an Orientation constraint, you can access its properties via the Orientation Constraint rollout in the Motion panel. In this rollout you can add or delete targets, assign weighting, assign and animate target weight values, and adjust other, related parameters.
Note: When you assign an Orientation constraint via the Animation menu, the software assigns a Rotation List controller to your object. In the Rotation List rollout list you will find Orientation Constraint, which is the constraint you assigned. To view the Orientation Constraint rollout, double-click Orientation Constraint entry in the list.
Add Orientation Target: Adds new target objects that influence the constrained object.
Add World as Target: Aligns the constrained object to the world axis. You can weight the amount of influence that the world target has on the constrained object as you would any other target object.
Delete Orientation Target: Removes targets. Once a target is removed, it will no longer influence the constrained object.
Weight: Assigns and animates weight values for each target.
Keep Initial Offset: Preserves the original orientation of the constrained object. When you turn off Keep Initial Offset, the object adjusts itself to match the orientation of its target or targets. Default=off.