Simple Frogger game in Ruby 2d

frogger.rb

require 'ruby2d'

GRID_SIZE = 80

set width: GRID_SIZE * 12
set height: GRID_SIZE * 9

frogger = Square.new(size: GRID_SIZE, color: 'olive', y: Window.height - GRID_SIZE, x: GRID_SIZE * 4)
trucks = []; boats = []; motorbikes = []; bicycles = []
game_state = :in_progress

on :key_down do |event|
  case event.key
  when 'left' then frogger.x -= GRID_SIZE
  when 'right' then frogger.x += GRID_SIZE
  when 'up' then frogger.y -= GRID_SIZE
  when 'down' then frogger.y += GRID_SIZE
  end
end

update do
  if game_state == :lost
    text ||= Text.new('YOU LOST, SORRY', x: 200, y: Window.height / 2, size: 72, color: 'red')
    Window.set(background: 'gray')
  elsif game_state == :won
    text ||= Text.new('YOU WON, YAY', x: 200, y: Window.height / 2, size: 72, color: 'blue')
    Window.set(background: 'gray')
  else
    if Window.frames % 110 == 0
      bicycles.push(Rectangle.new(width: GRID_SIZE * 1, height: GRID_SIZE, y: (GRID_SIZE * 7), x: 0 - (GRID_SIZE * 2), color: 'blue'))
    end

    if Window.frames % 110 == 0
      trucks.push(Rectangle.new(width: GRID_SIZE * 2, height: GRID_SIZE, y: (GRID_SIZE * 5), x: Window.width, color: 'purple'))
    end

    if Window.frames % 90 == 0
      boats.push(Rectangle.new(width: GRID_SIZE * 1.5, height: GRID_SIZE, y: (GRID_SIZE * 3), x: 0 - (GRID_SIZE * 2), color: 'orange'))
    end

    if Window.frames % 60 == 0
      motorbikes.push(Rectangle.new(width: GRID_SIZE * 0.8, height: GRID_SIZE, y: (GRID_SIZE * 1), x: Window.width, color: 'red'))
    end

    bicycles.each { |bicycle| bicycle.x += 2 }
    trucks.each { |truck| truck.x -= 3 }
    boats.each { |boat| boat.x += 4 }
    motorbikes.each { |motorbike| motorbike.x -= 2 }

    if (trucks + boats + motorbikes + bicycles).any? { |truck| truck.contains?(frogger.x + (frogger.width / 2), frogger.y + (frogger.height / 2))}
      game_state = :lost
    end

    if frogger.y == 0
      game_state = :won
    end
  end
end

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