TYPE: POP
TITLE: Attractor POP

The Attractor POP applies forces on the particles as determined by
the referenced attractor SOP. A SOP can be used as an attractor if it
has forces added to it. This can be done by using a Force SOP for metaballs 
or a Point SOP for face geometry types. 

This POP modifies the following attributes: accel.

Parameters:
    Activation              - Turns the POP on and off		/activate
    Source Group            - Subset of points to act on
Attractor
    Attractor Use           - How the attractor points affect particles
        All points                - All points affect each particle
        Single point per particle - Only one point affects each particle
                                    Each particle is assigned to one
                                    attractor point only.
    Geometry Source         - Specifies where the POP should get
                              the attractor Object and SOP
    SOP                     - Attractor SOP
    Ignore Transform Object - Transform geometry to transform object space
    Stop At Attractor       - Particle comes to a complete stop when it
                              reaches the attractor.
    Scale                   - Overall force scaling factor	/scale
    Show attractor radius in guide - Show the radius of effect as guide geo
    Show acceleration in guide - Show the applied acceleration as guide geo
Defaults
    Ignore Charge           - Ignore particle charge 
    Override Charge         - Override charge attribute
    Charge                  - Charge to use			/charge
    Ignore Mass             - Ignore particle mass 
    Override Mass           - Override particle mass
    Mass                    - Mass to use for override		/mass
Noise
    Seed       - Seed for random turbulence generator 		/seed
    Turbulence - # of iterations to add fractional noise	/turb
    Roughness  - Scale of noise added with each iteration	/rough
    Exponent   - Noise attenuation				/atten
    Frequency  - Spatial frequency of noise field	/freqx /freqy /freqz
    Amplitude  - Maximum value of noise field			/amp
    Offset     - Amount to shift noise		/offsetx /offsety /offsetz
    Noise Type - Noise type to generate	

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

See Also: Fan, Force, Wind
