shell-whiz-toolkit/shell_scripts/super_fun/rainbow.sh

clear;x=$(($COLUMNS/2));y=$(($LINES/2));c=0;n=1;a=90;while :;do bgc=$(($c%232 + 16));case "$a" in 0)xd=0;yd=-1;n=$(($n+1));; 90)xd=1;yd=0;; 180)xd=0;yd=1;n=$(($n+1));; 270)xd=-1;yd=0 ;; *) break ;; esac; for ((i=0;i < $n;i++));do if [[ $x -ge $COLUMNS || $x -le 0 || $y -ge $LINES || $y -le 0 ]]; then x=$(($COLUMNS/2));y=$(($LINES/2));n=1;a=0; continue ; fi ; printf "\033[%s;%sH\033[48;5;%sm \033[0m" $y $x $bgc ; x=$(( $x + $xd )); y=$(( $y + $yd )); done ; c=$(( $c + 1 )); a=$(( $(( $a + 90 )) % 360 )) ; sleep 0.001; done