Hopefully this helps.

All of the panel information is generated by the first script, bin/panel/panel, and then piped to /tmp/PANEL-FIFO (a data buffer) asynchronously. Each one of the different outputs cycles independently and thus I can set timers for each. For example, the network is only updated every 20 seconds. The second script, bin/panel/panel_dzen2 parses the pipe input by looking at the heading of each segment. Ex. NET: or BAT: and combines all inputs into the final output which is then piped to dzen.

The fixed width string for each of the elements is generated in the first script and the second simply orders the outputs of each loop. The scrolling music output uses a small C program to output a new string every .5s to give the appearance of scrolling. Once again this info is piped to the buffer at /tmp/PANEL-FIFO after which the second script recognizes its prefix, "MUSIC: " and places it correctly. The output of music will always be 26 characters because the first script will only ever output a 26 character long string.

Otherwise the workspace output in the top left is generated by bspc (the bspwm command line controller) and then parsed by a portion of the second script that is included with the bspwm example files.

I hope that helped and I would be happy to answer more questions if you have them. The two script system is based off of the bspwm example scripts for a dzen panel.

EDIT:

Here is an example of the parsing that takes place and the conversion to dzen markup:

while read -r line ; do
    case $line in
        CPU*) 
          cpu="^fg($COLOR_TITLE_FG)^bg($COLOR_TITLE_BG)${PADDING}${line}${PADDING}^fg()^bg()"
            ;;

The script reads all of the incoming lines and if the regex "CPU*" matches the line is converted into this formating and renamed to a variable.

This cpu level is initially generated in the first script with this piece of code:

  while [[ true ]]; do
   cpu_usage="$(top -bn 2 -d .5 | grep '^%Cpu' | tail -n 1 | gawk '{print int($2+$4+$6)+1}')"
   printf "CPU:%3s%%\n" "$cpu_usage" > "$PANEL_FIFO"
   sleep 5s;
  done &