bold="\033[1m"; normal="\033[0m"; red="\033[0;31m"
underline_on="\033[4m";underline_off="\033[24m";
blink_on="\033[5m"; blink_off="\033[25m"
invisible_on="\033[25h"; invisible_off="\033[25l"
erase_end_of_screen="\033[0J"
up_delete_line () { tput cuu1; tput el; }
line_4_delete_eol () { tput cup 4 0; echo -e "\033[0J"; }

#!/bin/sh
rm -f tstfil
rm -f tstfil2
rm -f tstfil3
# NOTE should make cursor invisible during display
echo "^[[40m"      # Set BG to black
clear              # goes with black
echo "^[[40m^[[1;37m" # Set FG (stars) to bold;white
knt=50             # Make 50 astronomic bodies
wid=`tput cols`    # Get width of display screen
base=`tput lines`  # Get bottom line of screen

# Create background scene of random stars
while [ $knt -gt 0 ]
do
  y=`expr $RANDOM % $wid`    # Create random y value
  x=`expr $RANDOM % $base`   # Create random x value
  tput cup $x $y             # Position for next astro body
  if [ `expr $knt % 8` == 0 ]
  then echo "^[[40m^[[1;31m¤^[[0m"        # Red Dwarf star
  else if [ `expr $knt % 10` == 0 ]
       then echo "^[[40m^[[1;32m§^[[0m"   # Green galaxy
       else echo "^[[40m^[[1;37m.^[[0m"   # Regular star
       fi
  fi
  knt=`expr $knt - 1`
done

# FIND text to display at end of script and COPY it to a file
txln=`egrep "^>" spactst2 | wc -l`
tail -$txln spactst2 > tstfil # Put history into a file

# Create file of lines with ">" 1st character removed & centered
while read line
do
   line=`echo ${line:1}`     # Drop 1st char in line (>)
   echo $line | \
   sed -e :a -e "s/^.\{1,$wid\}$/ &/;ta" -e 's/\( *\)\1/\1/' \
       >> tstfil2            # Output centered line to 2nd file
done < tstfil                # Input file
# Create "WIPE" file of spaces & with size to fit history display
for i in $(seq 1 $base)
do
   printf "%${wid}s\n" >> tstfil3  # Print line of spaces "$wid" wide
done

# Read successively more lines and as head moves up due to nl
# bump line start likewise
# NOTE: To prevent new lines merging with old ones this must start
#       above the very last screen line and the positioning of lines
#       using tput must be 1 above because of new line output.
echo "^[[40m^[[1;37m"        # Make FG white and bold
n=`wc -l tstfil2 | cut -d" " -f1` # Get lines in 2nd file
base=`expr $base - 1`        # Reset baseline prevents line push up 
for i in $(seq 1  $n)
do
   base=`expr $base - 1`     # Moves up another line 
   tput cup $base 0
   head -$i tstfil3          # Wipes current diplay of text plus 1
   tput cup $base 0
   head -$i tstfil2          # Text now 1 line longer
   sleep 2
done
echo "^[[0m"                 # Return to default colors
exit

>In the year 1492 ol' Big Chris hit the boards and sailed off
>on a quest thought as foolish to our parents.
>Traveling to the Moon is as likely..
>Yet today here we are with flags and streamers.
>We welcome a much slimmer Christopher Columbus and his
>bounty.
>Let us hope that we will be less critical of
>our explorers and scientists when they reach for the stars
>or the Yetti.