module FM_World
  FM_VIEW_SWITCH    = 15
end

class Game_Event
  attr_accessor   :fm_event

  alias :init_public_members_fm_world_sigma :init_public_members
  def init_public_members
    init_public_members_fm_world_sigma
    @fm_event = false
  end

  alias :init_private_members_fm_world_sigma :init_private_members
  def init_private_members
    init_private_members_fm_world_sigma
    @through_original = @through
    @transparent_original = @transparent
  end

  alias :update_fm_world_sigma :update
  def update
    refresh_fm_state
    update_fm_world_sigma
  end

  def refresh_fm_state
    if @fm_event
      @through = !$game_variables[FM_World::FM_VIEW_SWITCH]
      @transparent = !$game_variables[FM_World::FM_VIEW_SWITCH]
    else
      @through = @through_original
      @transparent = @transparent_original
    end
  end
end

class Game_Interpreter
  alias :comment_call_fm_world_sigma :comment_call
  def comment_call
    call_fm_event
    comment_call_fm_world_sigma
  end

  def call_fm_event
    note.scan(/<fm>/i) do
      $game_map.events[event_id].fm_event = true
    end
  end
end