TYPE: POP
TITLE: Location POP

The Location POP births particles from a given location in space. Local
variables are usable in parameters denoted with a *.

Parameters:
Location
    System               - Coordinate system to use:
        Cartesian        - Specify the location with x, y and z coordinates
        Cylindrical      - Specify the location with radius, theta and z 
                           coordinates (where theta is the angle between the 
                           x and y axes)
        Polar            - Specify the location with radius, theta and phi 
                           coordinates (where phi is the angle between the 
                           x and z axes)
    *Coordinates          - Birth location                                  /loc
Birth
    Impulse Activation   - Turns impulse birthing on and off    /impulseactivate
    Impulse Birth Rate   - Number of particles to birth per cook    /impulserate
    Constant Activation  - Turns constant birthing on and off  /constantactivate
    Constant Birth Rate  - How many particles to birth per second  /constantrate
    Birth Group          - Group to contain birthed points
    Preserve Group       - Add particles to group instead of replacing.
    *Life Expectancy     - How long the particle will live in seconds      /life
    *Life Variance       - Variance of life expectancy in second        /lifevar
Attributes
    *Velocity            - Used to set or add to velocity      /velx /vely /velz
    *Variance            - Variance of set or added velocity   /varx /vary /varz
    Ellipsoid Distribution - Distribute the velocities in a spheroid of size 
                           determined by Variance, rather than a cube.
    Add ID Attributes    - Add ID and parent attributes
    Add Generation Attribute - Add generation attribute
    Add Origin Attribute - Add origin attribute
    *Origin Index        - Index as used in origin                  /originindex
    Add Speed Attribute  - Add speed attribute (length of velocity vector)

Local Variables
    BBX BBY BBZ    - bounding box           
    TX TY TZ       - position 

See Also: Source, Split, Stream
