-- love2d bit operation test

bit = require("bit")

function love.load()
  tm = 0
  v = 0
end

function love.update(dt)
  tm = tm + dt
  local st = 0.2
  if tm >= st then
    tm = tm - st
    v = bit.band(v + 1, 0x0f)
  end
end

function love.draw()
  love.graphics.clear(0, 0.25, 0.5, 1.0)

  local s = ""
  for i=0,3 do
    local msk = bit.lshift(1, i)
    if bit.band(v, msk) == 0 then
      s = "0"..s
    else
      s = "1"..s
    end
  end

  love.graphics.print(s, 10, 40)
end

function love.keypressed(key, isrepeat)
  if key == "escape" then
    -- ESC to exit
    love.event.quit()
  end
end