Super event sensor

#:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=
# Simple Event Sensor
# Version: 1.10
# Author : LiTTleDRAgo
#:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=
#
# Instruction :
#  
# Set the event name to : <Sensor(RANGE)>
# example :
#            <Sensor4>
#
# If player is in event sensor range, Self switch A (default) will turned ON
#
#:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=:=

class Game_Event < Game_Character
 #-----------------------------------------------------------------------
  SENSOR_SELF_SWITCH = 'A'
 #-----------------------------------------------------------------------
  alias drago64c_update update
  def update
    sensor_updating unless @unsensor
    drago64c_update  
  end

  def sensor_updating
    @event.name =~ /<Sensor(\d+)>/i
    s = [$1.to_i,[$game_map.map_id,@id,SENSOR_SELF_SWITCH],[]]
    s[2] = [(($game_player.x-self.x).abs + ($game_player.y-self.y).abs <=
          s[0]), $game_self_switches[s[1]]] if s[0] > 0
    return unless s[0] > 0 && s[2][0] != s[2][1]
    $game_self_switches[s[1]], $game_map.need_refresh = s[2][0], true
  end
end