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Spinners, Heartbeats, Progress, Waiting, Idle, Loading Indicators

Various character sequences that can be used to show a program is working, and
has not stalled.  That is the program is still working (looping), or is waiting
for some input of some kind.  Generally when you have no definate 'progress' so
you don’t know how much longer it would take...

I generally only show sequences of at least 4+ characters...

Many of the following spinners I figured out myself, especially the longer
'clock' and 'cycle' sequences, and are not found in any of the other sources of
spinners I know about...

Some other sources, including...
  https://stackoverflow.com/questions/2685435/cooler-ascii-spinners
  https://gist.github.com/ellemenno/9489706
  https://github.com/sindresorhus/cli-spinners/blob/HEAD/spinners.json
  https://github.com/sindresorhus/cli-spinners/blob/master/spinners.json

It looks as is many of these copy from each other, which is hardly surprising.
Some are also designed to be multi-character.

WARNING: Some of these 'library' defined spinner providers run the spinner in
a seperate process, which means they are not truely telling the user if the
main program has stalled, only it is still present on the system, creating
a false expectation.

NOTE: If the terminal is a remote ssh connection, then network delays can
cause some fast (or longer) clocks to behave slightly erratic, as changes
become grouped.

Anthony Thyssen, July 2020

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Using a Spinner

To really see or understand what many of these look like you need to
demonstrate them.  This is especially true of some of longer 'Braille'
sequences.

Perl Spinner/Heartbeat demonstrator (Unicode complaint)

  perl -CO -Mutf8 -e '$|=1; $c=" ▏▎▍▌▋▊▉█";
    while(1){ for $i ($c=~/(.)/g) {
      print "  $i\r"; select(undef,undef,undef,.1+1/length($c)); } };'


Python version (no time delay)

  =======8<--------
  while True:
    for i in '-≺‹⟨|⟩›≻':
      print('\b' + i, end='')
  =======8<--------

If there are many choices for a unicode character in a Spinner,
it is often best to select from the same unicode block
for widest glyph simularities in different fonts.

A Reference for unicode characters
   https://antofthy.gitlab.io/info/data/utf8-demo.txt


Shell usage example (not unicode complient)...

  =======8<--------
  spinner='-\|/';
  spinlen=${#spinner}
  timeout=30    # timeout in seconds

  printf -v start '%(%s)T' -1  # save the start time
  while true; do
    # wait for some contition
    # if finished...
    #   printf "Condition has been met\r"  # success, and clean wait line
    #   break
    # fi

    # Timeout check
    printf -v elapsed '%(%s)T' -1  # current time
    elapsed=$(( elapsed - start )) # elapsed time
    if (( elapsed > timeout )); then
      echo "Timeout waiting for contition"  # timeout, and clean wait line
      break
    fi

    # Wait line with spinner...
    char=$(( (char+1)%spinlen ))
    printf "Waiting... %c %d sec\r" "${spinner:$char:1}" $elapsed
    sleep .2   # loop sleep, minimum spin rate
  done
  =======8<--------

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ASCII Spinner/Heartbeat Character Sequences

Replace each character with next, in a loop
A patrol is the same sequence going forward then reverse


Spinning Line         "-\|/"     (for coding use... "-\\|/")
(This was made famous by Sun Workstations Boot sequence)

Pulsing Circle:       ".oOo"
Balloon:              " .oO@*"

Flip line:            "__\|/__"          (for coding "__\\|/__")
Flip line (patrol):   "__\|/____/|\__"   (for coding "__\\|/____/|\\__")

Folding Over:         "-<|>-"       patrol:  "->|<--<|>-"
Pacman Muncher:       "->|>-"

Bat and Ball:         "dqpb"

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Unicode Spinner/Heartbeat Character Sequences

Unicode Spinning Line        "─╲│╱"    but really, just use ASCII version!

Flip Line Quote:             "_-`'´-_"    I think it could be better!

Folding Over:                "-≺‹⟨|⟩›≻"       patrol:  "-≻›⟩|⟨‹≺-≺‹⟨|⟩›≻"
Pacman Muncher:              "-≻›⟩›≻-"

Quarter Circle Spinner:      "◟◜◝◞"
Extended Circle Spinner:     "◜◠◝◞◡◟"
Corner Circle Spinner:       "◴◷◶◵"
Half Circle Spinner:         "◐◓◑◒"        small in some fonts
Half Circle Flip:            "◡⊙◠⊙"
Ellipses:                    " ․‥…"

Rain Circle:                 " ⋅∘○⨀"
Pulsing Circle               "◌○⊙●⊙○"
Pulsing Dot:                 "⋅∙●∙"
Pulsing Heart:               "⋅•❤•"
Pulsing Line:                "❘❙❚❙❘"
Pulsing Heart:               "❘❙❚❤❚❙❘"     depends on font
Pulsing Square:              "▪◼█◼▪"

Corner Spinner:              "⌞⌜⌝⌟"
Large Corner Spinner:        "⎿⎾⏋⏌"
Corner Box Spinner:          "◰◳◲◱"
Triangle Spinner:            "◣◤◥◢"
Triangle Pulse Spinner:      "▫◸◤◸▫◹◥◹▫◿◢◿▫◺◣◺"
Triangle Pulse Spinner2:     "■◤◸◤■◥◹◥■◢◿◢■◣◺◣"

Moving Horizontal Bar:       "⎽⎼―⎻⎺ "       patrol: "⎽⎼―⎻⎺⎻―⎼"
Moving Vertical Bar:         "▏⎢⎪⎥▕ "       patrol: "▏⎢⎪⎥▕⎥⎪⎢"
Tone Bar:                    "˩˨˧˦˥"        patrol: "˩˨˧˦˥˦˧˨"
Rising Vertical Bar:         "ˌ╷❘ﺍ╵ˈ"

Growth & Decay:              "․|†¥∨⌄"
Pulsing Star:                "⋅˖+⟡✧⟡+˖"
Pulsing Plus:                "⋅˖+┼╋┼+˖"
Bouncing Bubble:             "'°º¤ø,¸¸,ø¤º°'"
Mathematical Equals:         "−=≡"
Mathematical Compares:       "≑≒≑≓"
Arrow Spinner:               "←↖↑↗→↘↓↙"
Dingbat Arrow Patrol:        "➵➴➵➶"    bold:   "➸➷➸➹"

Noise Fading:                "█▓▒░ "
Quarter Block Spinner:       "▘▝▗▖"
Half Block Spinner:          "▄▌▀▐"
Quarter Block Worm:          "▘▀▝▐▗▄▖▌"
Diagonally Moving Block:     " ▖◼▝ ▗◼▘"

Box Bar Horizontal:          " ▏▎▍▌▋▊▉█"    patrol: " ▏▎▍▌▋▊▉█▉▊▋▌▍▎▏"
Box Bar Vertical:            " ▁▂▃▄▅▆▇█"    patrol: " ▁▂▃▄▅▆▇█▇▆▅▄▃▂▁"
(with some reverse video these can be made fancier)

Half Line Spinner:           "╷╴╵╶"
Half Line Spinner Bold:      "╻╸╹╺"
Half Line Spinner Pulsed:    "╷╴╹╶"
Pulsing Half Line Spinner:   "╷╴╵╶╻╸╹╺"
Moving Line:                 "╴━╶ "
Rotating Moving Line:        "╴━╶╷┃╵╶━╴╵┃╷"
Wind-shield Wiper Patrol:    "╷╴╵╶╷╷╷╶╵╴╷╷"
Pipe Spinner:                "┤┘┴└├┌┬┐"
Pipe Spinner Bold:           "┫┛┻┗┣┏┳┓"
Pipe Spinner Mixed:          "┤┙┚┴┖┕├┍┎┬┒┑"
Two Handed Clock (16):       "╹┖╿┚┕╺┍╼╽┎╻┒┙╾┑╸"
Two Handed Cycle (20):       "╹┖╿┚╹╺┍╼┕╺╻┒╽┎╻╸┙╾┑╸"

---
NOTE: Braille Glyphs work well as spinners, but the glyphs are not good when
used with most True Type fonts as 'Braille Space', ('⠀') is not blank, but a
set of empty circles, making the use of them, even as braille, problematical!

Braille Circling Dot:        "⡀⠄⠂⠁⠈⠐⠠⢀"
Braille Circling Hole:       "⢿⣻⣽⣾⣷⣯⣟⡿"
Braille Twin Circling Dots:  "⡈⠔⠢⢁"
Braille Two Dots Take Turns: "⢄⢂⢁⡈⡐⡠"

Braille Bouncing Dot:        "⡀⠄⠂⠁⠁⠂⠄"    right-side:  "⢀⠠⠐⠈⠈⠐⠠"
Braille Bounce Side-Side:    "⡀⠄⠂⠁⠈⠐⠠⢀⠠⠐⠈⠁⠂⠄"
Braille Bouncing Ball:       "⣤⠶⠛⠛⠶"      yes there is a 'pause' at the top
Braille Climber:             "⣀⡠⠤⠢⠒⠊⠉⠑⠒⠔⠤⢄"
Braille Coveyer Belt:        "⣸⢼⢺⢹⡏⡗⡧⣇"
Braille Up-Down Belt:        "⣸⢼⢺⢹⢺⢼⣸⣇⡧⡗⡏⡗⡧⣇"

___Braille 6 dot___
Braille 6 Worm:              "⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏"
Braille 6 Bounce Worm:       "⠄⠆⠇⠋⠙⠸⠰⠠⠰⠸⠙⠋⠇⠆"
Braille Zigzag Worm:         "⠋⠙⠚⠞⠖⠦⠴⠲⠳⠓"
Braille Zigzag Stop:         "⠋⠙⠚⠒⠂⠂⠒⠲⠴⠦⠖⠒⠐⠐⠒⠓"
Braille 6 Step Left:         "⠁⠉⠙⠚⠒⠂⠂⠒⠲⠴⠤⠄⠄⠤⠴⠲⠒⠂⠂⠒⠚⠙⠉⠁"
Braille 6 Step Right:        "⠈⠉⠋⠓⠒⠐⠐⠒⠖⠦⠤⠠⠠⠤⠦⠖⠒⠐⠐⠒⠓⠋⠉⠈"
Braille 6 Step Both (30):    "⠁⠁⠉⠙⠚⠒⠂⠂⠒⠲⠴⠤⠄⠄⠤⠠⠠⠤⠦⠖⠒⠐⠐⠒⠓⠋⠉⠈⠈⠉"
Braille Two Dot Clock (36):  "⠂⠃⠊⠒⠢⠆⠃⠁⠉⠑⠡⠅⠊⠉⠈⠘⠨⠌⠒⠑⠘⠐⠰⠔⠢⠡⠨⠰⠠⠤⠆⠅⠌⠔⠤⠄"
Braille Two Dot Cycle (42):  "⠂⠃⠊⠒⠢⠆⠂⠁⠉⠑⠡⠅⠃⠁⠈⠘⠨⠌⠊⠉⠈⠐⠰⠔⠒⠑⠘⠐⠠⠤⠢⠡⠨⠰⠠⠄⠆⠅⠌⠔⠤⠄"


___Braille 8 dot___
Braille Worm:                "⠋⠙⠹⠸⢰⣰⣠⣄⣆⡆⠇⠏"
Braille Worm Uturn:          "⠋⠙⠹⠸⢰⣰⣠⣄⣆⡆⡖⠖⠚⠙⠋⠏⠇⡆⣆⣄⣠⣰⢰⢲⠲"
Braille Step Left (36):      "⠁⠉⠙⠚⠒⠂⠂⠒⠲⠴⠤⠄⠄⠤⢤⣠⣀⢀⢀⣀⣠⢤⠤⠄⠄⠤⠴⠲⠒⠂⠂⠒⠚⠙⠉⠁"
Braille Step Right (36):     "⠈⠉⠋⠓⠒⠐⠐⠒⠖⠦⠤⠠⠠⠤⡤⣄⣀⢀⢀⣀⣄⡤⠤⠠⠠⠤⠦⠖⠒⠐⠐⠒⠓⠋⠉⠈"
Braille Step Both (40):      "⠁⠁⠉⠙⠚⠒⠂⠂⠒⠲⠴⠤⠄⠄⠤⢤⣠⡀⡀⣀⢀⢀⣄⡤⠤⠠⠠⠤⠦⠖⠒⠐⠐⠒⠓⠋⠉⠈⠈⠉"
Braille Stacking Dots (40):  "⠀⡀⠄⠂⠁⠈⠐⠠⢀⣀⢄⢂⢁⢈⢐⢠⣠⢤⢢⢡⢨⢰⣰⢴⢲⢱⢸⣸⢼⢺⢹⣹⢽⢻⣻⢿⣿⣶⣤⣀"
Braille Two Dot Clock (64):
   "⠂⠃⠊⠒⠢⢂⡂⠆⠃⠁⠉⠑⠡⢁⡁⠅⠊⠉⠈⠘⠨⢈⡈⠌⠒⠑⠘⠐⠰⢐⡐⠔⠢⠡⠨⠰⠠⢠⡠⠤⢂⢁⢈⢐⢠⢀⣀⢄⡂⡁⡈⡐⡠⣀⡀⡄⠆⠅⠌⠔⠤⢄⡄⠄"
Braille Two Dot Cycle (72):
   "⠂⠃⠊⠒⠢⢂⡂⠆⠂⠁⠉⠑⠡⢁⡁⠅⠃⠁⠈⠘⠨⢈⡈⠌⠊⠉⠈⠐⠰⢐⡐⠔⠒⠑⠘⠐⠠⢠⡠⠤⠢⠡⠨⠰⠠⢀⣀⢄⢂⢁⢈⢐⢠⢀⡀⡄⡂⡁⡈⡐⡠⣀⡀⠄⠆⠅⠌⠔⠤⢄⡄⠄"

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Special 2 Character, Braille "Dot Loading" Sequence...

  perl -CO -Mutf8 -e '$|=1;
    $c="⢀⠀⡀⠀⠄⠀⢂⠀⡂⠀⠅⠀⢃⠀⡃⠀⠍⠀⢋⠀⡋⠀⠍⠁⢋⠁⡋⠁⠍⠉⠋⠉⠋⠉";
    $c.="⠉⠙⠉⠙⠉⠩⠈⢙⠈⡙⢈⠩⡀⢙⠄⡙⢂⠩⡂⢘⠅⡘⢃⠨⡃⢐⠍⡐⢋⠠⡋⢀⠍⡁⢋⠁⡋⠁⠍⠉⠋⠉⠋⠉";
    $c.="⠉⠙⠉⠙⠉⠩⠈⢙⠈⡙⠈⠩⠀⢙⠀⡙⠀⠩⠀⢘⠀⡘⠀⠨⠀⢐⠀⡐⠀⠠⠀⢀⠀⡀";
    while(1){ for $i ($c=~/(..)/g) {
      print "  $i\r"; select(undef,undef,undef,.2); } };'

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Line Sequences

Sonar
   "    .    "
   "    o    "
   "   (O)   "
   "  (( ))  "
   " ((( ))) "
   "(((   )))"
   "((     ))"
   "(       )"
   "         "

Scrolling arrows and bouncing balls are straight forward to implement.
The individual characters interchangeable, So I only represent a example frame,
to give you the idea.  They are all reversable and you can mix and match as
needed.

   "▐ ⋅     ▌"
   "|  •    |"
   "(   ●   )"

   " ──▷       "
   "  ══➤      "
   "   ──➤     "
   "    ⋅•●    "
   "   ·⸫⸪>=-  "

   "··●········"

   "⠀⠀⠀⠀⠄⠀⠀⠀⠀⠀⣺"     braille dots falling into a stack (tetris-like)

   "▐⠀⠀⠁⠂⠄⡀⠄⠀⠀▌"     bluncing like a game "Pong" (bad with true type fonts)

   "______|\___"     shark fin swiming back and forth


Also see Bar Graphing, next...

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Bar Graphs and Progess Reporting...

These are not spinners, but use for generating horizontal bar graphs.
See Unicode percent script
  https://antofthy.gitlab.io/software/#percent_utf

ASCII Only     "-" "=", "#" "▒"   (single character graphs)
ASCII Seq      "-=#"              (not great)
Hash Chars     "░▒▓█"
Half chars     "▌█",
Quarter chars  "▖▌▛█"
Incremental    "▏▎▍▌▋▊▉█"   <--- the ideal 8 character increment
Braille chars  "⡀⡄⡆⡇⣇⣧⣷⣿"   braille character each 8 increments

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