#+TITLE: Polybar config (Deprecated)
#+setupfile: headers
#+OPTIONS: auto-id:t
#+HTML_HEAD_EXTRA: <meta name="description" content="Phundrak's polybar config" />
#+HTML_HEAD_EXTRA: <meta property="og:title" content="Phundrak's polybar config" />
#+HTML_HEAD_EXTRA: <meta property="og:description" content="Description of the polybar config file of Phundrak" />
#+PROPERTY: header-args :exports none
#+PROPERTY: header-args:emacs-lisp :tangle no :exports none
#+PROPERTY: header-args:conf-windows :tangle ~/.config/polybar/config :noweb yes :exports code :mkdirp yes

* Presentation
  :PROPERTIES:
  :CUSTOM_ID: Presentation-4e723f32
  :END:
  *Before proceeding, be  aware that I deprecated this polybar  config on August
  22nd, 2020, meaning I  won’t update it anymore unless I use  it again some day
  in the future. I will keep it on my website though.*

  Polybar is  a desktop utility  for displaying  various information in  form of
  bars for GNU/Linux systems. It is often  used as a replacement for native bars
  available in window managers,  such as i3. In my case, I  use two instances of
  polybar in  order to get  two bars displayed  on each screen.  The information
  displayed is either related to i3 itself, or it is system information, such as
  CPU or disk usage. More information will be given and explained below.

  If you want  to learn more about how  to configure Polybar, you can  go to its
  [[https://github.com/jaagr/polybar][official repository on Github]].

  #+BEGIN_EXPORT latex
  Be aware  that this PDF  documents suffers from a  couple of issues  with some
  characters such  as emojis. If you  wish to see everything  correctly, I would
  suggest  you to  take a  look at  the online  HTML version  of this  document.
  #+END_EXPORT

* General settings
  :PROPERTIES:
  :CUSTOM_ID: General_settings-e02fb78c
  :END:
  Some general settings are available for Polybar, and they are declared under
  the ~[settings]~ section.
  #+BEGIN_SRC conf-windows
  [settings]
  #+END_SRC
  Only one setting is used in this configuration though: the ability to relauch
  polybar on a configuration file rewrite.
  #+BEGIN_SRC conf-windows
    screenchange-reload = true
  #+END_SRC

  Some global settings are also available in order to adjust the
  ~_NET_WM_STRUT_PARTIAL~ top and bottom values:
  #+BEGIN_SRC conf-windows
    [global/wm]
    margin-top = 32
    margin-bottom = 22
  #+END_SRC

* Colors declaration for polybar
  :PROPERTIES:
  :CUSTOM_ID: Colors_declaration_for_polybar-75ee0b65
  :END:
  #+BEGIN_SRC conf-windows :exports none
    ; -*- mode: conf-windows -*-
  #+END_SRC
  Like most status  bars available, we can  declare custom colors to  be used in
  polybar. This  part of the configuration  file is declared with  the following
  header:
  #+BEGIN_SRC conf-windows
  [colors]
  #+END_SRC

  As I use pywal as a color scheme generator based on the color of my wallpaper,
  I need  to tell polybar  to fetch the  colors it will  use from xrdb.  If such
  color cannot  be used, other  colors will be  used as fallback  colors. First,
  let’s  declare  our  default  background  and  foreground  colors  with  their
  alternative option.
  #+BEGIN_SRC conf-windows
    background = ${xrdb:color1:#50000000}
    background-alt = ${xrdb:color2:#444}
    foreground = ${xrdb:color7:#dfdfdf}
    foreground-alt = ${xrdb:color6:#555}
  #+END_SRC

  Now, we can also declare our primary and secondary colors.
  #+BEGIN_SRC conf-windows
    primary = #ffb52a
    secondary = #e60053
  #+END_SRC

  Polybar is  also aware of  alerts sent  by window managers  such as i3  when a
  window  opens in  an unfocused  workspace. For  that, let’s  declare an  alert
  color.
  #+BEGIN_SRC conf-windows
    alert = #bd2c40
  #+END_SRC

* Declaration of the bars
  :PROPERTIES:
  :CUSTOM_ID: Declaration_of_the_bars-a95135a3
  :END:
  It is  possible in i3 to  declare as many bars  as we wish, and  each of these
  bars will be named. Naming the bar is done in its module declaration like so:
  #+BEGIN_SRC conf-windows :tangle no
  [bar/nameofthebar]
  #+END_SRC
  In my configuration, I use two of such bars, one atop of my screen, and one at
  the bottom.

** Top bar declaration
   :PROPERTIES:
   :CUSTOM_ID: Declaration_of_the_bars-Top_bar_declaration-fc0cd977
   :END:
   As unimaginative as it  might seem, I went for a rather  explicit name for my
   bars. The top one is simply named ~top~, as shown below.
   #+BEGIN_SRC conf-windows
   [bar/top]
   #+END_SRC

*** Positioning
    :PROPERTIES:
    :CUSTOM_ID: Declaration_of_the_bars-Top_bar_declaration-Positioning-2505760c
    :END:
    We need  to set on which  screen the bar is  to be displayed. Indeed,  it is
    possible  to display  a bar  on  only one  specific  screen if  we wish  to.
    Actually, it  is even the  default behavior of polybar,  but as we  will see
    later with the  launching script, it is possible to  launch bars on multiple
    outputs at  the same  time. Here, we  simply get the  value of  the variable
    ~monitor~ from the launch environment.
    #+NAME: monitor-bar
    #+BEGIN_SRC conf-windows
    monitor = ${env:MONITOR}
    #+END_SRC

    We have a few position-related variables that need to be set. We can specify
    whether or  not we want our  bar at the bottom  of the screen —which  is the
    default behavior  of polybar—,  its width,  its height,  the radius  for the
    rounding of its corners and whether the bar should be centered or not. In my
    case, my  bars are  rather small  height-wise, and it  occupies most  of the
    width of my screens.  There is some gaps between this bar  and the border of
    the screen, but this is due to a border around the bar itself which acts not
    only on the width of the bar itself, but also on its height.
    #+BEGIN_SRC conf-windows
      bottom = false
      border-size = 5
      <<position-bar-top>>
    #+END_SRC

    #+NAME: position-bar-top
    #+BEGIN_SRC conf-windows :exports none :tangle no
      width = 100%
      height = 22
      radius = 10.0
      fixed-center = true
    #+END_SRC
    We also want to add some padding to our bar so our modules are not too close
    to its edges, especially due to the rounding of the top bar.
    #+NAME: padding-bar
    #+BEGIN_SRC conf-windows
      padding-left = 2
      padding-right = 4
    #+END_SRC

    Each module will  have some padding around it, so  that modules aren’t glued
    together and instead have some room to breathe. The padding on the left is a
    bit less than the padding on the right for aesthetic reasons.
    #+NAME: module-margin-bar
    #+BEGIN_SRC conf-windows
      module-margin-left = 1
      module-margin-right = 2
    #+END_SRC

    The top bar doesn’t include any system tray, so let’s disable that.
    #+BEGIN_SRC conf-windows
      tray-position = none
    #+END_SRC

*** Colors and display
    :PROPERTIES:
    :CUSTOM_ID: Declaration_of_the_bars-Top_bar_declaration-Colors_and_display-30f12652
    :END:
    As  explained above,  we declared  some global  variables when  it comes  to
    colors, and this is where they will be used. The bar’s background will be of
    the same color  as the main background color declared  earlier, and the same
    goes for the foreground.
    #+NAME: bar-colors
    #+BEGIN_SRC conf-windows
      background = ${colors.background}
      foreground = ${colors.foreground}
    #+END_SRC

    If we wanted, we could also declare a default color for the underlines under
    the various modules that  will be included in the bar, but  in our case this
    variable is unused. So  we will simply add this commented  line as a memento
    this  is  possible,  but  it  won’t   have  any  effect  with  this  current
    configuration of polybar. Same  goes for the border around the  bar, it is a
    useless  variable in  this  configuration since  we want  the  border to  be
    transparent.
    #+NAME: line-border-color
    #+BEGIN_SRC conf-windows
      line-color = #f00
      ; border-color = #00000000
    #+END_SRC

    Although the variable for the default line  color is not used, we still have
    to set the default width of the  underline of our modules. By default, their
    underline will be three pixels thick.
    #+NAME: line-size-bar
    #+BEGIN_SRC conf-windows
      line-size = 3
    #+END_SRC

*** Fonts and locale
    :PROPERTIES:
    :CUSTOM_ID: Declaration_of_the_bars-Top_bar_declaration-Fonts_and_locale-70a25466
    :END:
    Now we can  chose which font fill be  used in order to display  text in this
    bar, as well as the locale we want. The locale will be useful for displaying
    information such as  date and time, which  is a module we will  have in this
    top bar. First, the declaration of the locale is done like so:
    #+NAME: locale-bar
    #+BEGIN_SRC conf-windows
      locale = ja_JP.UTF-8
    #+END_SRC

    Now, we can declare  the fonts we want to use in Polybar.  It is possible to
    declare several of  them, the first one  is the one which  gets the absolute
    priority, and  the next ones  with a larger  index are fallback  fonts. Font
    declaration accepts the fontconfig format  as well as possible offset[fn:1].
    Five fonts are used in my polybar config:
    #+NAME: fonts-polybar
    | Font         | fontconfig                                         | Vertical offset | Why it’s used         |
    |--------------+----------------------------------------------------+-----------------+-----------------------|
    | Fira Sans    | Fira Sans Book:style=Book:pixelsize=10             |               1 | Text display          |
    | IPA Mincho   | IPAMincho:style=regular:pixelsize=6                |               0 | Japanese text display |
    | Unifont      | unifont:fontformat=truetype:size=6:antialias=false |               0 | Fallback font         |
    | NotoEmoji    | NotoEmoji:style=Book:scale=16                      |               0 | Emoji display         |
    | Siji         | Siji:pixelsize=8                                   |               0 | Symbol display        |
    | Default font | fixed:pixelsize=8                                  |               0 | Fallback font         |

    #+NAME: font-ws-config
    #+HEADER: :var text="font"
    #+BEGIN_SRC emacs-lisp :var table=fonts-polybar :cache yes
      (setq counter 0)
      (mapconcat (lambda (font)
                   (setq counter (+ 1 counter))
                   (format "%s-%d = %s;%s"
                           text
                           (- counter 1)
                           (nth 1 font)
                           (nth 2 font)))
                 table
                 "\n")
    #+END_SRC

    #+RESULTS[567cfb5e5a0bdfb0eca90846c8292b7d3fd585ea]: font-ws-config
    : font-0 = Fira Sans Book:style=Book:pixelsize=10;1
    : font-1 = IPAMincho:style=regular:pixelsize=6;0
    : font-2 = unifont:fontformat=truetype:size=6:antialias=false;0
    : font-3 = NotoEmoji:style=Book:scale=16;0
    : font-4 = Siji:pixelsize=8;0
    : font-5 = fixed:pixelsize=8;0

    Here’s the font configuration:
    #+BEGIN_SRC conf-windows
      <<font-ws-config(text="font",table=fonts-polybar)>>
    #+END_SRC

    Note that only Fira Sans get a small  offset due to the size of the font and
    the height of the bar itself.

*** Modules
    :PROPERTIES:
    :CUSTOM_ID: Declaration_of_the_bars-Top_bar_declaration-Modules-18979638
    :END:
    Finally, arguably one of the most  important parts of our bar configuration:
    the module selection. Modules can be  positioned in three different parts of
    our bar: to  the right, in middle or  to the left. On the left,  we want our
    workspace  indicator for  i3. In  the  middle, we’ll  get the  title of  the
    focused window, and to the left we’ll have the date and time.
    #+NAME: modules-generate
    #+BEGIN_SRC emacs-lisp :var table=top-modules :results value :cache yes
      (setq right '()
            center '()
            left '())
      (dolist (module table)
        (let* ((module-name (nth 0 module))
               (module-layout (nth 1 module)))
          (message "%S" module-layout)
          (add-to-list (cond
                        ((string= "left" module-layout) 'left)
                        ((string= "center" module-layout) 'center)
                        (t 'right))
                       module-name)))
      (concat (concat "modules-left = "
                      (mapconcat #'identity left " ")
                      "\n")
              (concat "modules-center = "
                      (mapconcat #'identity center " ")
                      "\n")
              (concat "modules-right = "
                      (mapconcat #'identity right " ")
                      "\n"))
    #+END_SRC

    #+RESULTS[90b932dc0fd32501e1513f14059b92de09a7b59e]: modules-generate
    : modules-left = i3
    : modules-center = xwindow
    : modules-right = date

    Here is the list of modules used:
    #+NAME: top-modules
    | Module name | Position | Brief description          |
    |-------------+----------+----------------------------|
    | i3          | left     | i3 workspace indicator     |
    | xwindow     | center   | Name of the focused window |
    | date        | right    | Date and time              |

    #+BEGIN_SRC conf-windows :cache yes
      <<modules-generate(table=top-modules)>>
    #+END_SRC

    Each module will be described in details later in this document.

** Bottom bar declaration
   :PROPERTIES:
   :CUSTOM_ID: Declaration_of_the_bars-Bottom_bar_declaration-8504b5ec
   :END:
   As  described above,  we will  once again  have to  declare our  bar with  an
   equally unimaginative but explicit name.
   #+BEGIN_SRC conf-windows
   [bar/bottom]
   #+END_SRC

*** Positioning
    :PROPERTIES:
    :CUSTOM_ID: Declaration_of_the_bars-Bottom_bar_declaration-Positioning-b1883756
    :END:
    The  variables are  the same  as above,  but two  of them  will be  slightly
    modified:
    #+BEGIN_SRC conf-windows
      bottom = true
      border-size = 0
      <<position-bar-bottom>>
    #+END_SRC

    #+NAME: position-bar-bottom
    #+BEGIN_SRC conf-windows :exports none :tangle no
      width = 100%
      height = 22
      radius = 0.0
      fixed-center = true
    #+END_SRC

    When it comes to the bottom bar, I prefer to have it fit my outputs, without
    any margin around  it. And of course, I  have to declare it as  being at the
    bottom of the  screen, hence these modifications. As regards  the padding of
    our modules, their own margins, and the screen output, they aren’t modified.
    #+BEGIN_SRC conf-windows
      <<padding-bar>>
      <<module-margin-bar>>
      <<monitor-bar>>
    #+END_SRC

    However, we do display  the system tray on this bottom bar  at its right. It
    has no padding and  it is not detached from the bar (this  allows the bar to
    be displayed under the icons of the system tray), and their maximum size was
    chosen so they are well visible without being too big.
    #+BEGIN_SRC conf-windows
      tray-position = right
      tray-padding = 0
      tray-detached = false
      tray-maxsize = 15
    #+END_SRC

*** Colors and display
    :PROPERTIES:
    :CUSTOM_ID: Declaration_of_the_bars-Bottom_bar_declaration-Colors_and_display-854aae82
    :END:
    Nothing  changes from  the top  bar, all  the variables  stay with  the same
    values. See [[#Declaration_of_the_bars-Bottom_bar_declaration-Colors_and_display-854aae82][Colors and display]] of the top bar for more information.
    #+BEGIN_SRC conf-windows
      <<bar-colors>>
      <<line-border-color>>
      <<line-size-bar>>
    #+END_SRC

*** Fonts and locale
    :PROPERTIES:
    :CUSTOM_ID: Declaration_of_the_bars-Bottom_bar_declaration-Fonts_and_locale-67459d62
    :END:
    Again, nothing changes  from the top bar,  so for more info  on what’s going
    on, see [[#Declaration_of_the_bars-Top_bar_declaration-Fonts_and_locale-70a25466][Fonts and locale]] of the top bar.
    #+BEGIN_SRC conf-windows
      <<locale-bar>>
      <<font-ws-config(text="font",table=fonts-polybar)>>
    #+END_SRC

*** Modules
    :PROPERTIES:
    :CUSTOM_ID: Declaration_of_the_bars-Bottom_bar_declaration-Modules-702b21fc
    :END:
    Now, we can get to something interesting  again: modules. This bar has a lot
    more modules than  the top bar. Here is  the list of the modules  we have on
    the bottom bar:
    #+NAME: table-modules-bottom
    | Module name    | Position | Brief description               |
    |----------------+----------+---------------------------------|
    | mpd            | left     | MPD status indicator            |
    | filesystem     | right    | Free storage in our filesystem  |
    | wlan           | right    | Name of the active WiFi network |
    | eth            | right    | Local address on Ethernet       |
    | volume         | right    | System volume                   |
    | backlight-acpi | right    | Screen backlight                |
    | cpu            | right    | CPU usage                       |
    | memory         | right    | RAM usage                       |
    | temperature    | right    | CPU temperature                 |
    | custom-battery | right    | Battery usage                   |

    Here’s the corresponding configuration:
    #+ATTR_LATEX: :options breaklines
    #+BEGIN_SRC conf-windows
      <<modules-generate(table=table-modules-bottom)>>
    #+END_SRC
    All these modules will be explained below.

    As you may have noticed, no modules  will be displayed in the middle of this
    bar.

* Modules
  :PROPERTIES:
  :CUSTOM_ID: Modules-2e1a51bc
  :END:
  Before we begin to  describe the different modules, I would  like to point out
  something that will be repeated multiple times  if I don’t talk about it right
  now: for each module, it is  possible to declare the foreground and background
  color of  the prefix of the  modules, as well  as the underline color  and the
  padding of the module. I like these parameters to be rather consistent, so the
  code block you  will see below will  often be reused. The colors  refer to the
  colors declared earlier, and the padding is minimal.
  #+NAME: mod-prefix-col
  #+BEGIN_SRC conf-windows :tangle no
    format-prefix-foreground = ${colors.foreground-alt}
    format-prefix-underline = ${colors.secondary}
    format-underline = ${colors.secondary}
    format-padding = 1
  #+END_SRC

** Hardware
   :PROPERTIES:
   :CUSTOM_ID: Modules-Hardware-26426ebd
   :END:
*** Battery
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-Battery-299f2e42
    :END:
    This  module allows  the user  to  get a  battery widget  among the  polybar
    modules that will also send a notification  to the user if the battery level
    drops below a certain value. This module relies on ~polybar-another-battery~
    ([[https://github.com/drdeimos/polybar_another_battery][link]]) and its generated binary ~polybar-ab~ which should be in the ~$PATH~.

    The  first line  of the  module declaration  lets the  user name  the module
    however they want. In this case, the name is ~custom-battery~.
    #+BEGIN_SRC conf-windows
      [module/custom-battery]
    #+END_SRC

    Since it is not  a core module, we have to declare it  as a custom script so
    polybar knows what to do with it.
    #+BEGIN_SRC conf-windows
      type = custom/script
    #+END_SRC

    We now can specify the script execution,  and whether or not the script will
    be continuously outputting  something. In our case, the answer  to this last
    question is yes.
    #+BEGIN_SRC conf-windows
      exec = polybar-ab -polybar -thr 10
      tail = true
    #+END_SRC
    The ~-thr 10~ specifies the threshold for polybar-ab at which it should warn
    the user about the battery level of the computer.

    Of course, users on desktop computers  won’t need this module which is aimed
    at laptop users. Feel free to remove it if you do not need it.

*** Filesystem
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-Filesystem-26f0a3c6
    :END:
    This module  allows to display  information about our  filesystem, including
    (and this  is what  I use  this module  for) displaying  the used  space and
    remaining space on different mount points. This module is an internal module
    to polybar, so let’s declare it as such:
    #+BEGIN_SRC conf-windows
      [module/filesystem]
      type = internal/fs
    #+END_SRC
    We can specify how  often the filesystem is to be  checked with the variable
    ~interval~. I prefer it  not to check it too often in order  to not ping too
    often  my drives,  but  I want  it  to be  often enough  so  it is  somewhat
    responsive. This is why I settled on a 20 seconds interval.
    #+BEGIN_SRC conf-windows
      interval = 20
    #+END_SRC

    We now have to indicate where  our different filesystems are mounted. In the
    case of my main computer /Marpa/,  I have two partitions, the root partition
    and  the home  partition. But  on my  travel laptop,  I only  have the  root
    partition, hence the usage of the  below Elisp code that determines based on
    the computer it is running whether or  not the second mount point to my home
    partition should be included.
    #+NAME: include-home-partition
    #+BEGIN_SRC emacs-lisp :tangle no :exports code
      (if (string= system-name "Marpa")
          "mount-1 = /home")
    #+END_SRC

    #+BEGIN_SRC conf-windows
      mount-0 = /
      <<include-home-partition()>>
    #+END_SRC

    Now we can  set the format of  our module. There are two  mains formats, one
    for mounted  and one for unmounted  mountpoints. For both, we’ll  simply use
    their label.
    #+BEGIN_SRC conf-windows
      format-mounted = <label-mounted>
      format-unmounted = <label-unmounted>
    #+END_SRC
    When it comes to  the mounted partition, we want to display  the name of the
    mountpoint and how used it is, both in terms of gigabytes and percentage.
    #+BEGIN_SRC conf-windows
      label-mounted = 💽 %mountpoint%: %used%/%total% (%percentage_used%%)
      label-mounted-foreground = ${colors.foreground}
      label-mounted-underline = ${colors.secondary}
    #+END_SRC

    If  the  volume is  unmounted  (which  should  be worrying  considering  the
    mountpoints chosen), then we’ll simply have a message telling us about that,
    and the foreground color will use the alternative foreground color described
    earlier.
    #+BEGIN_SRC conf-windows
      label-unmounted = %mountpoint% not mounted
      label-unmounted-foreground = ${colors.foreground-alt}
    #+END_SRC

*** Xbacklight
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-Xbacklight-2901c504
    :END:
    This module is used in order to display the level of brightness of a screen.
    It  is not  used  by itself,  but  rather  by other  modules,  such as  [[#Modules-Hardware-ACPI_backlight-9eaeaa79][ACPI
    backlight]]. First of  all, this module is an internal  module for xbacklight.
    It will  also display the  brightness percentage,  prefixed by a  sun emoji.
    Lastly, it will be underlined by a green line.
    #+BEGIN_SRC conf-windows
      [module/xbacklight]
      type = internal/xbacklight
      format = <label>
      label = %percentage%%
      format-prefix = "🌞 "
      format-underline = #9f78e1
    #+END_SRC

*** ACPI backlight
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-ACPI_backlight-9eaeaa79
    :END:
    This module  indicates the backlight  level of a  screen thanks to  the ACPI
    Linux module. There isn’t much to tell about the module itself other than it
    inherits the module  described above, [[#Modules-Hardware-Xbacklight-2901c504][xbacklight]]. It also  sets which driver
    should be used, in this case the ~intel_backlight~ driver.
    #+BEGIN_SRC conf-windows
      [module/backlight-acpi]
      inherit = module/xbacklight
      type = internal/backlight
      card = intel_backlight
    #+END_SRC

*** CPU
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-CPU-365dcb98
    :END:
    This module indicates how  much of the CPU is being used.  As shown below, I
    made it so  we can see the  load on each core.  The first thing to  do is to
    declare the module as an internal module dedicated to the CPU.
    #+BEGIN_SRC conf-windows
      [module/cpu]
      type = internal/cpu
    #+END_SRC

    Now, we can set the refresh rate in  seconds of the module. I like it at two
    seconds:
    #+BEGIN_SRC conf-windows
      interval = 2
    #+END_SRC

    Now, let’s  declare what will  be displayed. The  format will be  a computer
    emoji followed by ramp characters.
    #+BEGIN_SRC conf-windows
      format = <label> <ramp-coreload>
      format-prefix = "💻 "
      label = %percentage%%
      ramp-coreload-0 = ▁
      ramp-coreload-1 = ▂
      ramp-coreload-2 = ▃
      ramp-coreload-3 = ▄
      ramp-coreload-4 = ▅
      ramp-coreload-5 = ▆
      ramp-coreload-6 = ▇
      ramp-coreload-7 = █
    #+END_SRC

    Finally, this module will be underlined in red.
    #+BEGIN_SRC conf-windows
      format-underline = #f90000
    #+END_SRC

*** Memory
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-Memory-2f2f9475
    :END:
    Similarly to the CPU  module, it is possible for Polybar  to display the RAM
    load of  the computer. As  above, let’s declare  this module as  an internal
    module to Polybar:
    #+BEGIN_SRC conf-windows
      [module/memory]
      type = internal/memory
    #+END_SRC

    As the CPU module still, the refresh rate will be of two seconds.
    #+BEGIN_SRC conf-windows
      interval = 2
    #+END_SRC

    Its format will be the percentage of used RAM, prefixed by a disk emoji.
    #+BEGIN_SRC conf-windows
      format = <label>
      format-prefix = "💿 "
      label = %gb_used%
    #+END_SRC

    Lastly, it will be underlined in green.
    #+BEGIN_SRC conf-windows
      format-underline = #4bffdc
    #+END_SRC

*** Wlan
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-Wlan-3457f36b
    :END:
    It is possible for  Polybar to display the name of  the current WiFi network
    the computer is  connected to. For that,  we first need to  declare the Wlan
    module as an internal module of Polybar.
    #+BEGIN_SRC conf-windows
      [module/wlan]
      type = internal/network
    #+END_SRC

    Now,  we should  set the  name  of the  interface.  As this  depends on  the
    hardware I  am using, I am  going to rely  on the machine’s hostname  and on
    some Elisp code to get this setting right.
    #+NAME: name-wlan-interface
    #+BEGIN_SRC emacs-lisp :exports code :tangle no
      (cond ((string= system-name "Marpa") "wlp8s0")
            ((string= system-name "gampo") "wlp3s0"))
    #+END_SRC

    #+BEGIN_SRC conf-windows
      interface = <<name-wlan-interface()>>
    #+END_SRC

    The name of the current WiFi network will be refreshed every three seconds.
    #+BEGIN_SRC conf-windows
      interval = 3.0
    #+END_SRC

    The format of the module when connected to a network will the the display of
    the antenna emoji,  followed by the name of the  network. When disconnected,
    the module will simply be empty.
    #+BEGIN_SRC conf-windows
      format-connected = <label-connected>
      format-connected-prefix = "📶 "
      label-connected = %essid%
    #+END_SRC

*** Ethernet
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-Ethernet-dc749304
    :END:
    Just like  any other module,  the ethernet module has  to be declared  as an
    internal module.
    #+BEGIN_SRC conf-windows
      [module/eth]
      type = internal/network
    #+END_SRC

    And  just like  the Wlan  module, it  requires an  interface which  can vary
    depending on the machine I am using, hence this piece of Elisp:
    #+NAME: name-eth-interface
    #+BEGIN_SRC emacs-lisp :exports code :tangle no
      (cond ((string= system-name "Marpa") "enp9s0")
            ((string= system-name "gampo") "enp0s25"))
    #+END_SRC

    #+BEGIN_SRC conf-windows
      interface = <<name-eth-interface()>>
    #+END_SRC

    The format of this  module will be the local address of  the computer on the
    network, and  it will be  prefixed by  a desktop computer  emoji. Meanwhile,
    when disconnected, the module won’t be visible.
    #+BEGIN_SRC conf-windows
      format-connected = <<label-connected>>
      format-connected-prefix = "🖥 "
      label-connected = %local_ip%
      format-disconnected =
    #+END_SRC

    The module will be underlined in green.
    #+BEGIN_SRC conf-windows
      format-connected-underline = #55aa55
    #+END_SRC

*** Volume
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-Volume-ebf9f7a4
    :END:
    The volume  module in Polybar  is linked to  its internal bindings  to ALSA.
    Let’s declare it accordingly.
    #+BEGIN_SRC conf-windows
      [module/volume]
      type = internal/alsa
    #+END_SRC

    Its format is quite  simple: if the audio is not muted,  it is then prefixed
    with a speaker emoji, followed by the volume percentage.
    #+BEGIN_SRC conf-windows
      format-volume = <label-volume>
      format-volume-prefix = "🔈 "
      label-volume = %percentage%%
    #+END_SRC

    If the audio is muted, then the only thing the user will see is the muted
    speaker emoji followed by the text “muted”.
    #+BEGIN_SRC conf-windows
      format-muted-prefix = "🔇 "
      label-muted = muted
    #+END_SRC

    In any case, it will be underlined in green.
    #+BEGIN_SRC conf-windows
      format-volume-underline = #55aa55
    #+END_SRC

*** Temperature
    :PROPERTIES:
    :CUSTOM_ID: Modules-Hardware-Temperature-a9f08cde
    :END:
    The temperature module checks the temperature of the CPU, and warns the user
    above a certain threshold of heat, in my case if my CPU is above 60°C.
    #+BEGIN_SRC conf-windows
      [module/temperature]
      type = internal/temperature
      thermal-zone = 0
      warn-temperature = 60
    #+END_SRC

    The  format  of  the  module  is  the  thermometer  emoji  followed  by  the
    temperature of  the CPU. If  the CPU becomes too  hot, the text  will change
    color for the secondary foreground color.
    #+BEGIN_SRC conf-windows
      format = <label>
      format-underline = #f50a4d
      format-warn = <label-warn>
      format-warn-underline = ${self.format-underline}
      format-prefix = "🌡 "
      format-warn-prefix = "🌡 "

      label = %temperature-c%
      label-warn = %temperature-c%
      label-warn-foreground = ${colors.secondary}
    #+END_SRC

** Software
   :PROPERTIES:
   :CUSTOM_ID: Modules-Software-f6529189
   :END:
*** Window title
    :PROPERTIES:
    :CUSTOM_ID: Modules-Software-Window_title-3f931641
    :END:
    This module’s  aim is to  simply provide the  name of the  currently focused
    window given by Xorg. This module is  an internal module to polybar, that is
    to say it is  built-in, and is of the type ~xwindow~.  So, let’s declare the
    module  accordingly, including  the piece  of  common code  declared at  the
    beginning of the chapter:
    #+BEGIN_SRC conf-windows
      [module/xwindow]
      type = internal/xwindow
      <<mod-prefix-col>>
    #+END_SRC

    Now we  can take care of  the label, which is  the actual text that  will be
    displayed. In our case,  we want the label to be the title  of the current X
    window, hence  the value of ~label~,  and we don’t  want it to be  too long,
    though I’m not sure I’ve often seen window titles longer than 70 characters.
    #+BEGIN_SRC conf-windows
      label = %title%
      label-maxlen = 70
    #+END_SRC

*** i3
    :PROPERTIES:
    :CUSTOM_ID: Modules-Software-i3-db36ddfb
    :END:
    Now  comes the  module for  i3  interaction. Thanks  to this  module, it  is
    possible to show which workspaces are active and focused, and it is possible
    to change  workspaces by clicking on  the ones displayed in  the bar. First,
    let’s declare it; it is an internal module by the way.
    #+BEGIN_SRC conf-windows
      [module/i3]
      type = internal/i3
    #+END_SRC

    Now, let’s display only the workspaces  that are on the current output. This
    means if a workspace  is either inactive or on another  screen or output, it
    won’t be displayed.
    #+BEGIN_SRC conf-windows
      pin-workspaces = true
    #+END_SRC

    We also want our workspaces to be sorted by number rather than by output.
    #+BEGIN_SRC conf-windows
      index-sort = true
    #+END_SRC

    I don’t want  to be able to  scroll through the workspaces when  my mouse is
    hovering  the  module:  when it  happens,  most  of  the  time it  was  done
    accidentally. So let’s  deactivate that. However, I sometimes  like to click
    on them to switch from one another, so we’ll keep that activated.
    #+BEGIN_SRC conf-windows
      enable-scroll = false
      wrapping-scroll = false
      reverse-scroll = false
      enable-click = true
    #+END_SRC

    This parameters splits the workspaces’ name on ~:~. Let’s deactivate that.
    #+BEGIN_SRC conf-windows
      strip-wsnumbers = false
    #+END_SRC

    An on  the topic of workspaces’  name, ~fuzzy-match~ allows the  user to use
    fuzzy search  for workspaces’  name when  we will  be applying  custom names
    below. Not really useful since I  only use the default workspaces’ name, but
    it’s good to have it enabled by default.
    #+BEGIN_SRC conf-windows
      fuzzy-match = true
    #+END_SRC

    The label  format is described first  by its label,  but also by one  of its
    three possible modes: focused, visible or unfocused. These will be discussed
    later, but for now let’s simply set our format.
    #+begin_src conf-windows
      format = <label-state> <label-mode>
    #+end_src

    We  also wand  to set  the label  mode to  be whichever  mode the  workspace
    described by polybar is in. This label will also have a padding of 2 pixels,
    and the text will be written in white.
    #+begin_src conf-windows
      label-mode = %mode%
      label-mode-padding = 2
      label-mode-foreground = #000
    #+end_src

**** Workspace icons
     :PROPERTIES:
     :CUSTOM_ID: Modules-Software-i3-Workspace_icons-89237191
     :END:
     Now, let’s name our workspaces. We can give them whatever name we want them
     to have, but I just like the aesthetics of Japanese characters, so let’s go
     with the kanji equivalent of the number of the workspaces.
     #+NAME: ws-names
     | workspace number | name |
     |------------------+------|
     |                1 | 一   |
     |                2 | 二   |
     |                3 | 三   |
     |                4 | 四   |
     |                5 | 五   |
     |                6 | 六   |
     |                7 | 七   |
     |                8 | 八   |
     |                9 | 九   |
     |                0 | 十   |

     Here are the corresponding configuration lines:
     #+BEGIN_SRC conf-windows
     <<font-ws-config(text="ws",table=ws-names)>>
     #+END_SRC

     In case we create a workspace which isn’t  named from ~0~ to ~9~, I want it
     to appear as is.
     #+begin_src conf-windows
       ws-icon-default = %index%
     #+end_src

**** Focused workspaces
     :PROPERTIES:
     :CUSTOM_ID: Modules-Software-i3-Focused_workspaces-0ca3b93d
     :END:
     Now we can define the label itself. First, we will need to define the label
     when the workspace is focused. We’ll simply take the alternative background
     for the  focused label, and the  underline will be defined  from Xrdb’s 8th
     color, with yellow  as the fallback color.  It will also have  a two pixels
     padding. The text itself will be the dynamic icons declared above.
     #+begin_src conf-windows
       label-focused = %icon%
       label-focused-background = ${colors.background-alt}
       label-focused-underline = ${xrdb:color8:#ffff00}
       label-focused-padding = 2
     #+end_src

**** Visible workspaces
     :PROPERTIES:
     :CUSTOM_ID: Modules-Software-i3-Visible_workspaces-4be78e50
     :END:
     The  ~visible~  label is  related  to  the  ~focused~  labels since  it  is
     describing workspaces that can be seen, but are not currently focused, i.e.
     a workspace that  appears on another screen than the  one currently used so
     it is  visible, but it isn’t  focused. The difference with  the ~unfocused~
     workspaces is that  the latter are neither focused nor  visible. As you can
     see, we are simply using all of the declarations from above for the focused
     labels so we can ensure they appear the same way the focused labels do.
     #+begin_src conf-windows
       label-visible = ${self.label-focused}
       label-visible-background = ${self.label-focused-background}
       label-visible-underline = ${self.label-focused-underline}
       label-visible-padding = ${self.label-focused-padding}
     #+end_src

**** Unfocused workspaces
     :PROPERTIES:
     :CUSTOM_ID: Modules-Software-i3-Unfocused_workspaces-13063042
     :END:
     When it comes to the unfocused  label, there won’t be any custom background
     or underline, so  we’ll just copy the two remaining  lines from the focused
     labels for unfocused labels.
     #+begin_src conf-windows
       label-unfocused = %icon%
       label-unfocused-padding = 2
     #+end_src

**** Urgent workspaces
     :PROPERTIES:
     :CUSTOM_ID: Modules-Software-i3-Urgent_workspaces-ed2bd93c
     :END:
     Lastly, we get our urgent workspaces:  workspaces in which most of the time
     it’s just a popup that appeared  or a software that finally launched itself
     while working on something else on another workspace. To make it a bit more
     unique, let’s declare  its background as being the color  0 from xrdb, with
     some dark red as the fallback color. And as the other labels, the text will
     be the icon and it will have a two pixels padding.
     #+begin_src conf-windows
       label-urgent = %icon%
       label-urgent-background = ${xrdb:color0:#bd2c40}
       label-urgent-padding = 2
     #+end_src

*** Mpd
    :PROPERTIES:
    :CUSTOM_ID: Modules-Software-Mpd-4b1ec78e
    :END:
    Mpd is  a music server  for GNU/Linux  systems that interfaces  will several
    front-ends, including ncmpcpp (the main one I use), ncmpcpp and mpc. It also
    interfaces with polybar thanks to some built in commands.

    First, let’s declare our module as an internal module.
    #+BEGIN_SRC conf-windows
      [module/mpd]
      type = internal/mpd
    #+END_SRC

    The next  thing we  want to  do is  set the  label for  the module:  we will
    display both the title  and the name of the artist of  the song playing. The
    maximum length will be 70 characters.
    #+BEGIN_SRC conf-windows
      label-song = %title% - %artist%
      label-song-maxlen = 70
      label-song-ellipsis = true
    #+END_SRC

    While Mpd is  online, the format of  the module should be  the control icons
    and then the song label.
    #+BEGIN_SRC conf-windows
      format-online = <icon-prev> <toggle> <icon-next> <label-song>
      icon-prev = ⏭
      icon-stop = ⏹
      icon-play = ▶
      icon-pause = ⏸
      icon-next = ⏭
    #+END_SRC

    If Mpd is offline, then I would  like to display a short messages that tells
    the user so.
    #+BEGIN_SRC conf-windows
      format-offline = <label-offline>
      label-offline = 🎵 mpd is offline
    #+END_SRC

*** Date
    :PROPERTIES:
    :CUSTOM_ID: Modules-Software-Date-f7338626
    :END:
    This module is really  simple: it gives the current date.  It is an internal
    module, and as declared below, it updates every second:
    #+BEGIN_SRC conf-windows
      [module/date]
      type = internal/date
      interval = 1
    #+END_SRC

    The main  date and time format  is the standard one,  following the ISO-8601
    standard.
    #+BEGIN_SRC conf-windows
      date = %Y-%m-%d
      time = %H-%M-%S
    #+END_SRC

    It also has  an alternative format which I occasionally  use, which displays
    the date and time in the Japanese format.
    #+BEGIN_SRC conf-windows
      date-alt = %A %d, %B
      time-alt = %H:%M:%S
    #+END_SRC

    The format is quite simple: a clock emoji preceding the date and time.
    #+BEGIN_SRC conf-windows
      format-prefix = "🕑 "
      label = %date% %time%
    #+END_SRC

    This module is underlined in blue:
    #+BEGIN_SRC conf-windows
      format-underline = #0a6cf5
    #+END_SRC

* Footnotes
  :PROPERTIES:
  :CUSTOM_ID: Footnotes-62d05520
  :END:

[fn:1] [[https://github.com/polybar/polybar/wiki/Fonts][https://github.com/polybar/polybar/wiki/Fonts]]


#  LocalWords:  Siji pixelsize Fira Mincho IPAMincho Unifont unifont fontformat
#  LocalWords:  truetype antialias xwindow wlan eth acpi cpu