http://nekogata.hatenablog.com/entry/2013/02/09/233540 より

yabai_game_player.rb

# -*- coding: utf-8 -*-
class Player
  module MovingMode
    def self.create(velocity)
      return lambda{ |direction, position|
        case direction
        when :up
          position[:y] -= velocity[:y]
        when :down
          position[:y] += velocity[:y]
        when :left
          position[:x] -= velocity[:x]
        when :right
          position[:x] += velocity[:x]
        end
        return position
      }
    end
  end

  attr_reader :position
  def initialize(position)
    @position = position
    to_normal_mode
  end

  def to_normal_mode
    @moving_mode = MovingMode.create({x:10, y:10})
  end

  def to_fast_mode
    @moving_mode = MovingMode.create({x:20, y:20})
  end

  def to_kani_mode
    @moving_mode = MovingMode.create({x:40, y:5})
  end

  def to_nechigae_mode
    @moving_mode = MovingMode.create({x:-10, y:-10})
  end

  def move(direction)
    @position = @moving_mode.call(direction, @position)
  end
end

player = Player.new(:x => 100, :y => 100)
player.move(:up)
p player.position # => {:x => 100, :y => 90}

player.to_fast_mode #ここで倍速モードに
player.move(:down)
p player.position # => {:x => 100, :y => 110}

player.to_kani_mode
player.move(:up)
player.move(:left)
p player.position # => {:x => 60, :y => 105}

player.to_nechigae_mode
player.move(:up)
p player.position # => {:x => 50, :y => 105}