DoW Encounter Rate

#==============================================================================
#    Update Encounter Percentage
#    Version: 1.0
#    Author: modern algebra (rmrk.net)
#    Date: April 29, 2010
#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#  Description:
#
#    This script allows you to dynamically alter the rate at which encounters
#   happen. It is useful particularly for making items or skills that can
#   reduce or increase the rate of encounters. What this script does is allow
#   you to specify a variable to control encounter rate, so you can use events
#   and common events to change the percentage of the default at which
#   encounters occur.
#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#  Instructions:
#
#    Paste this script into its own slot in the Script Editor (F11) above Main
#   but below Materials.
#
#    To set up which variable you want to control Encounter Rate, go to line 38
#   and set UEP_CONTROL_VARIABLE_ID to the ID of the variable you want.
#
#    The in-game value of the variable that you set will be the modified
#   percentage of encounters.
#    EX: If that variable is set to 100, then the encounter rate will not
#   change at all. If it's set to 50, then encounters will occur half as
#   frequently. If it's set to 200, then encounters will occur twice as
#   frequently. As a default measure, when that variable is set to 0, then it
#   will not alter encounter rate in any way. If you set the variable to
#   anything below 0 then no encounters will occur at all.
#==============================================================================

#\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
#  EDITABLE REGION
#||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
# The ID of the variable that controls how the encounter rate is updated
UEP_CONTROL_VARIABLE_ID = 20
#||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
#  END EDITABLE REGION
#//////////////////////////////////////////////////////////////////////////////
#==============================================================================
# ** Game Variables
#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#  Summary of Changes:
#    aliased method - []=
#==============================================================================

class Game_Variables
  #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  # * Set Variable
  #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  alias malg_upep_setvar_7uj1 []= unless $@
  def []= (var_id, *args)
    old_val = self[var_id]
    malg_upep_setvar_7uj1 (var_id, *args)
    # Scale Encounter percentage if this is the control variable
    if var_id == UEP_CONTROL_VARIABLE_ID && old_val != self[var_id]
      $game_player.calc_encounter_percent (old_val)
    end
  end
end

#==============================================================================
# ** Game Player
#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#  Summary of Changes:
#    aliased method - update_encounter, make_encounter_count
#    new method - calc_enc_percent
#==============================================================================

class Game_Player
  #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  # * Make Encounter Count
  #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  alias modern_ueper_mkencnt_5fv1 make_encounter_count unless $@
  def make_encounter_count (*args)
    modern_ueper_mkencnt_5fv1 (*args)
    calc_encounter_percent
  end
  #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  # * Update Encounter
  #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  alias malg_uep_updenc_6yj2 update_encounter unless $@
  def update_encounter (*args)
    variable = $game_variables[UEP_CONTROL_VARIABLE_ID]
    return if variable.nil? || variable < 0
    malg_uep_updenc_6yj2 (*args) # Run Original Method
  end
  #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  # * Calculate Encounter Percentage
  #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  def calc_encounter_percent (old_mod = 100)
    variable = $game_variables[UEP_CONTROL_VARIABLE_ID]
    return if variable.nil? || variable < 0 || old_mod < 0
    old_mod = 100 if old_mod == 0
    variable = 100 if variable == 0
    @encounter_count = (@encounter_count*(old_mod.to_f / variable.to_f)).to_i
  end
end