Next EA bestseller

main.rb

#!/home/greg/.rvm/rubies/default/bin/ruby

require 'gosu'

# main class for the laser element in game
class Laser
  attr_reader :created_at, :x, :y, :created_by

  def initialize(window_size, angle, player)
    @window_size = window_size

    @image = Gosu::Image.new('./laser.png')

    @angle = angle
    # position = 0 (float)
    @x = @y = 0.0

    @created_at = Time.now
    @created_by = player
  end

  def warp(x, y)
    @x = x
    @y = y
  end

  def move
    @x += Gosu.offset_x(@angle, 10)
    @y += Gosu.offset_y(@angle, 10)
  end

  def valid?
    return false if @x >= @window_size[:x] || @y >= @window_size[:y]\
     || @x <= 0 || @y <= 0

    true
  end

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

# main player class, this is the spaceship flying around
class Player
  attr_reader :x, :y, :angle

  def initialize(window_size)
    @window_size = window_size

    @image = Gosu::Image.new('./player.png')

    # position, angle and velocity = 0 (float)
    @x = @y = @vel_x = @vel_y = @angle = 0.0
  end

  def warp(x, y)
    @x = x
    @y = y
  end

  def turn_left
    @angle -= 4.5
  end

  def turn_right
    @angle += 4.5
  end

  def accelerate
    @vel_x += Gosu.offset_x(@angle, 0.4)
    @vel_y += Gosu.offset_y(@angle, 0.4)
  end

  def de_accelerate
    @vel_x += Gosu.offset_x(@angle, -0.3)
    @vel_y += Gosu.offset_y(@angle, -0.3)
  end

  def move
    @x += @vel_x
    @y += @vel_y
    @x %= @window_size[:x]
    @y %= @window_size[:y]

    @vel_x *= 0.95
    @vel_y *= 0.95
  end

  def draw
    @image.draw_rot(@x, @y, 2, @angle)
  end

  # is the player ready to shoot another laser?
  def ready?(laser_pool)
    # the lasers that has been shot by this player
    my_lasers = laser_pool.select { |l| l.created_by == self }
    return true if my_lasers.empty?
    # return true if the last laser was shot more than 0.2 seconds ago
    true if my_lasers.last.created_at < Time.now - 0.2
  end

  # determine if the player was hit
  def hit?(lasers)
    return false if lasers.empty?

    laser_distance = lasers.reject { |l| l.created_by == self }.map do |l|
      Gosu.distance(x, y, l.x, l.y)
    end

    return false if laser_distance.min.nil?

    return [true, [x, y]] if laser_distance.min < 30.0

    false
  end
end

# main game window, inherits from gosu main window
class MainWindow < Gosu::Window
  def initialize
    @window_size = { x: 1280, y: 720 }

    # window size (x, y)
    super @window_size[:x], @window_size[:y]
    self.caption = 'Test Game'

    @player = Player.new(@window_size)
    # random start-pos
    @player.warp(rand * @window_size[:x], rand * @window_size[:y])

    @lasers = []

    @player2 = Player.new(@window_size)
    @player2.warp(*rand_pos)

    # background stuff
    @background_image = Gosu::Image.new('./battleground.jpg', tileable: true)

    @scores = { @player => 0, @player2 => 0 }
    @score_text = Gosu::Font.new(self, 'Arial', 40)
  end

  def rand_pos
    [rand * @window_size[:x], rand * @window_size[:y]]
  end

  def update
    # quit the game
    close if Gosu.button_down?(Gosu::KbEscape)

    @player.turn_left if button_down?(Gosu::KbA) || button_down?(Gosu::GpLeft)
    @player.turn_right if button_down?(Gosu::KbD) || button_down?(Gosu::GpRight)
    @player.accelerate if button_down?(Gosu::KbW) || button_down?(Gosu::GpUp)
    @player.de_accelerate if button_down?(Gosu::KbS) ||
                             button_down?(Gosu::GpDown)

    if button_down?(Gosu::KbSpace) || button_down?(Gosu::GpButton0)
      # can only create one laser per 0.2 seconds
      # check if last laser created was more than 0.2 seconds ago
      if @player.ready?(@lasers)
        @lasers << Laser.new(@window_size, @player.angle, @player)
        @lasers.last.warp(@player.x, @player.y)
      end
    end

    @player2.turn_left if button_down?(Gosu::KbLeft)
    @player2.turn_right if button_down?(Gosu::KbRight)
    @player2.accelerate if button_down?(Gosu::KbUp)
    @player2.de_accelerate if button_down?(Gosu::KbDown)

    if button_down?(Gosu::KbRightControl)
      # can only create one laser per 0.2 seconds
      # check if last laser created was more than 0.2 seconds ago
      if @player2.ready?(@lasers)
        @lasers << Laser.new(@window_size, @player2.angle, @player2)
        @lasers.last.warp(@player2.x, @player2.y)
      end
    end

    @player.move
    @player2.move
    @lasers.each(&:move)

    [@player, @player2].each do |p|
      hit_stat = p.hit?(@lasers)

      next if hit_stat == false

      @lasers.delete_if do |l|
        Gosu.distance(p.x, p.y, l.x, l.y) <= 30
      end

      p.warp(*rand_pos)
      @scores[p] += 1
    end
  end

  def draw
    @player.draw
    @player2.draw

    # remove laser if it hit someone
    @lasers.each do |b|
      if b.valid?
        b.draw
      else
        @lasers.delete_if do |b_|
          b_ == b
        end
      end
    end

    @background_image.draw(0, 0, 0)

    @score_text.draw("Player 1: #{@scores[@player]} \
 - Player 2: #{@scores[@player2]}", 10, 10, 10, 1, 1, 0xff_000000)
  end
end

window = MainWindow.new
window.show