TYPE: POP
TITLE: RBDConstrain POP

The RBDConstrain POP applies forces to rigid body particles to maintain
a constraint, such as keeping a particle at a fixed location in space,
or keeping one particle at a fixed location relative to another
particle.

Parameters:
    Activation       - Turns the POP on and off		/activate
    Force Object     - Name of Force Object to override POP parameter values
    Group A          - Particles to use as the first object in the constraint
    Object A         - Use particle with this value for its instance attribute
                       as the first object in the constraint
    Group B          - Particles to use as the second object in the constraint
    Object B         - Use particle with this value for its instance attribute
                       as the second object in the constraint
    Constraint Type  - The type of constraint to apply
Point To Nail
    Nail Point       - Point in space to keep the particle	/nailptx /mailpty /nailptz
    Object Point     - Offset from particle center of mass
                       to keep located at the nail point	/nailobjx /nailobjy /nailobjz
Point To Point
    Object A Point   - Offset from object A center of mass
                       to connect to object B	/ptobjax /ptobjay /ptobjaz
    Object B Point   - Offset from object B center of mass
                       to connect to object A	/ptobjbx /ptobjby /ptobjbz
Rotation
    Rotation Vector  - Vector in world space to align with
                       object vector	/rotvecx /rotvecy /rotvecz
    Object Vector    - Vector in object space to align with
                       rotation vector	/rotobjx /rotobjy /rotobjz

Local Variables 
    Overview - The standard local variables are usable in this POP.  Please
               refer to the Houdini manual for more details.
