Window

class Game < Chingu::Window
  def initialize
    super
    self.input = { :escape => :exit }

  end

  def update
    super
    self.caption = "FPS: #{self.fps}"
  end
end

Game Objects

class Player < Chingu::GameObject
  def initialize
    super
    self.x, self.y = 200, 200
    self.image = Image["ship.png"]
    self.input = {
        :holding_left  => :move_left,
        :holding_right => :move_right }
  end

  def move_left;  @x -= 3; end
  def move_right; @x += 3; end
end

Player.create

Collision Trait

class Asteroid < Chingu::GameObject
  traits :bounding_circle,
         :collision_detection
end

# in your gamestate or window
def update
  Player.each_collision(Asteroid) do |p,a|
    p.destroy
  end
end

Saving/Loading

class Level < Chingu::GameState
  def initialize
    load_game_objects

    self.input = {:s => :save_game_objects}
  end
end

Put it all together!