====== thrower ======

Fires creeper-creating sand particles toward a pre-determined position. Used by [[ixe:features:units:thrower|Thrower]].

__**Arguments**__

  ?fire_mode (int)
  :Fire mode (only responds to a value of 1; all others turn off the thrower)
  ?fire_delay (int)
  :Time between shots in game frames
  ?fire_particle_count (int)
  :Number of sand particles fired per shot
  ?fire_amt_per_particle (float)
  :Amount of creeper spawned by each sand particle (negative values spawn anticreeper)
  ?fire_pos (Vector2)
  :Map position sand particles are fired toward
  ?fire_force (float)
  :Velocity at which sand particles are fired
  ?fire_force_variance (float)
  :Maximum random deviation of fire_force
  ?fire_spread (float)
  :Maximum random deviation of fire_pos in map pixels
  ?particle_color (Vector4)
  :Color of fired sand particles
  ?particle_color2 (Vector4)
  :Color of fired sand particles' glow aura (also affects particle_color)
  ?particle_damage (int)
  :Type of units damaged by collisions with fired sand particles; 0 = none, 1 = enemies, 2 = player units, 3 = all
  ?particle_damage_amt (int)
  :Damage sand particles inflict on units (values exceeding a limit of 0-255 are wrapped)
  ?particle_max_age (int)
  :Time before fired sand particles die and drop their payload in game frames (a value of 0 produces particles that don't have a time limit)
  ?particle_ignore_occupied (bool)
  :If true, fired sand particles pass through sands; if false, particles die and release their payload when colliding with sands