lolboat.rb

require "gosu"

class Character
  def initialize(window)
    @window = window
    @sprite = Gosu::Image.new(@window, "sprite.gif", false)

    @x, @y = 100, @window.floor
    @counter = 0
    @angle   = 0
    @speed   = 1

    @rolling_duration = 25

    @movement = :halt
    @action   = :walking
    @modes = {
      :halt    => :movement,
      :left    => :movement,
      :right   => :movement,
      :walking => :action,
      :rolling => :action
    }
  end

  def update
    self.send(@action)
    @counter += 1
  end

  def draw
    @sprite.draw_rot(@x, @y, 1, @angle)
  end

  def set_mode(mode)
    cur_name  = "@#{@modes[mode]}"
    cur = instance_variable_get(cur_name)
    engage_name = "engage_#{mode}".to_sym
    send(engage_name) if cur != mode and respond_to? engage_name
    instance_variable_set(cur_name, mode)
  end

  def walking
    return if @rolling_lock
    move(@movement)
  end

  def engage_rolling
    @rolling_lock      = true
    @rolling_direction = @movement
    @rolling_counter   = 0
    @speed = 1.5
  end

  def rolling
    if @rolling_counter >= @rolling_duration and @angle < 10
      @speed = 1
      @angle = 0
      @rolling_lock = false
      set_mode(:walking)
      return
    end

    roll_speed = 5 * Math.sin(@rolling_counter * 0.01) + 6
    @angle += @rolling_direction == :right ? roll_speed : roll_speed * -1
    @angle %= 360

    @rolling_counter += 1

    move(@rolling_direction)
  end

  def move(direction)
    if direction == :left
      @x -= @speed
    elsif direction == :right
      @x += @speed
    end
  end
end

class Game < Gosu::Window
  attr_accessor :floor

  def initialize
    super 1024, 800, false
    self.caption = "Character Testing"

    @floor = 500
    @character = Character.new(self)
    @roll_key_prev_state = false
  end

  def update
    @character.set_mode(:left)  if button_down? Gosu::KbLeft
    @character.set_mode(:right) if button_down? Gosu::KbRight
    @character.set_mode(:halt)  unless button_down? Gosu::KbLeft or button_down? Gosu::KbRight

    temp = button_down? Gosu::KbRightShift
    @character.set_mode(:rolling) if @roll_key_prev_state and !temp
    @roll_key_prev_state = temp

    @character.update
  end

  def draw
    @character.draw
  end

  def button_down(id)
    close if id == Gosu::KbEscape or id == Gosu::KbQ
  end
end

window = Game.new
window.show