6/1 3/1 2/1 1/1 2/3 1/2 | J J J / .' .' | J | F / / .' | | F J / .' .' 1/3 | | J F / / .' .-' | F | J / .' .' .-' | F F F / / .' .-' 1/4 | J J J / .' .' .-' _.-' | J | F / / .' .-' _.-' 1/5 | | F J / .' .' .-' _.-' _.--' | | J F / / .' .-' _.-' _.--' 1/6 | F | J / .' .' .-' _.-' _.--' __.--' 1/7 | F F F / / .' .-' _.-' _.--' __.--' __..--' _.-' _.--' __.--' __..--' 1/8 _.--' __.--' __..--' __..--'' __.--' __..--' __..--'' __..--' __..--'' __..--'' -------------------------- 0 ...and if the line slopes the other way use L instead of F.
Source: https://ascii.co.uk/art/lines