gistfile1.lua

-- configuration - edit to your liking
wp_index = 1
wp_timeout  = 10
wp_path = "/path/to/wallpapers/"
wp_files = { "01.jpg", "02.jpg", "03.jpg" }
 
-- setup the timer
wp_timer = timer { timeout = wp_timeout }
wp_timer:connect_signal("timeout", function()
 
  -- set wallpaper to current index for all screens
  for s = 1, screen.count() do
    gears.wallpaper.maximized(wp_path .. wp_files[wp_index], s, true)
  end
 
  -- stop the timer (we don't need multiple instances running at the same time)
  wp_timer:stop()
 
  -- get next random index
  wp_index = math.random( 1, #wp_files)
 
  --restart the timer
  wp_timer.timeout = wp_timeout
  wp_timer:start()
end)
 
-- initial start when rc.lua is first run
wp_timer:start()