TYPE: POP
TITLE: Drag POP

The Drag POP applies drag forces on the particles. Drag is applied
in the opposite direction to the velocity. The drag applied is proportional 
to the particle's speed and drag coefficient. To help visualize the effect 
of this operator, turn on the template flag to view the acceleration guides.

This POP modifies the following attributes: accel.

Parameters:
    Activation       - Turns the POP on and off		/activate
    Source Group     - Subset of points to act on
    Apply to Linear Velocity  - Apply drag to the linear velocity of
                                the particles
    Apply to Angular Velocity - Apply drag to the angular velocity of
                                the particles
    Scale            - Overall scaling factor		/scale
    Ignore Mass      - Ignore particle mass 
    Override Mass    - Override particle mass
    Mass             - Mass to use for override		/mass
    Override Drag    - Override particle drag
    Drag             - Drag to use for override		/drag

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