Color pattern maker

-- pastebin get uR8v94ss color
os.pullEvent = os.pullEventRaw
scr_x, scr_y = term.getSize()
seed = math.random(1, 255)
local function rollOver(input, max)
    return math.floor(input % max)
end
local function getColor(input)
    return 2^rollOver(input, 16)
end
term.setBackgroundColor(colors.black)
term.clear()
term.setCursorPos(1,1)
y = 0
bacColor = 1
scrollUp = true
while true do
    if scrollUp then
        term.scroll(1)
        term.setCursorPos(1,scr_y)
    else
        term.scroll(-1)
        term.setCursorPos(1,1)
    end
    for x = 1, scr_x do
        txtColor = getColor(bacColor + seed + y)
        bacColor = getColor((((x + y) - seed) + (y * (seed / 50))) + 100)
        term.setBackgroundColor(bacColor)
        term.setTextColor(txtColor)
        write("#")
    end
    y = y + 1

    if scrollUp then
        term.scroll(1)
        term.setCursorPos(1,scr_y)
    else
        term.scroll(-1)
        term.setCursorPos(1,1)
    end

    for x = 1, scr_x do
        txtColor = getColor(bacColor + seed + y)
        bacColor = getColor((((x - y) + seed) - (y + (seed * 100))) * 100)
        term.setBackgroundColor(bacColor)
        term.setTextColor(txtColor)
        write("#")
    end
    y = y + 1

    if y >= 512 then
        y = 0
        scrollUp = not scrollUp
        seed = math.random(1, 255)
    end
    sleep(0)
end