Wipe animation (CC)

-- pastebin get fVWPp88e wipe
local doWipe = function()
    local scr_x, scr_y = term.getSize()
    local cols = "f7"
    local length = scr_x/2
    local render = function(col1,col2,prog,forwards)
        term.setCursorPos(1,1)
        local screen = (col1:rep(prog)..col2:rep(length-prog)):rep(scr_x*scr_y):sub(1,(scr_x*scr_y))
        local line
        for a = forwards and 1 or scr_y, forwards and scr_y or 1, forwards and 1 or -1 do
            line = screen:sub((a-1)*scr_x+1,a*scr_x)
            term.setCursorPos(1,a)
            term.blit(("L"):rep(#line),line,line)
        end
    end
    local pos1 = 2
    local pos2 = pos1 - 1
    local forwards = true
    local reverse = false
    while true do
        for a = reverse and length or 1, reverse and 1 or length, reverse and -1 or 1 do
            render(cols:sub(pos1,pos1),cols:sub(pos2,pos2),a,forwards)
            sleep(0.0)
        end
           forwards = not forwards
        reverse = not reverse
        pos1 = (pos1 + 1)
        pos2 = (pos2 + 1)
        if pos1 > #cols then pos1 = 1 end
        if pos2 > #cols then pos2 = 1 end
    end
end
local mon = peripheral.find("monitor")
if mon then
    term.redirect(mon)
    mon.setTextScale(0.5)
end
doWipe()