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Manual Modules MOCCA MOCCA Tags

Constraint

Basic PSR Aim Up-Vector Parent Clamp Spring

Constraint

Constraints enable you to limit how far an object can move during the animation relative to another object or objects. There are many different types of constraint available that allow you to limit an object's movement, all of which you'll find in this tag.

Much of what the tag can do is also possible using XPresso. The advantage of the tag is that its constraints execute faster than their XPresso equivalents. The tag is also faster to set up and easier to use in many cases compared with using XPresso. Last but not least, a few of the tag's constraints are simply not possible to achieve using XPresso.

You can activate multiple constraints in the tag and define several targets for each constraint. This means that usually one tag is all you need to constrain the object; unless, that is, you want to set the constraints to different priorities. The tag's constraints are evaluated in the following order:

1. Parent
   
2. PSR
   
3. Clamp
   
4. Spring
   
5. Aim
   
6. Up Vector
   

If the constraint has more than one target, the targets are evaluated from top to bottom.

Not only is the tag useful for character animation, it is also generally useful for anything that moves in the scene. Even still scenes can benefit from the use of constraints. For example, you can use constraints to arrange objects on top of an uneven surface.