terminal colors tools and tutorial

在 terminal 和 vim 配色时，常会用到颜色名字或者对应的数字，一种方式就是查看网页，如 256 COLORS - CHEAT SHEET，另一种方便的方式，直接在命令行中输出颜色面板和名字，方便配色时引用。

检查当前 Terminal 是否支持 24bit 色彩

可以使用以下脚本，在命令行中运行一下，看输出的结果，可以判断当前 terminal 对 truecolors (24bit)支持的情况。

awk 'BEGIN{
    s="/\\/\\/\\/\\/\\"; s=s s s s s s s s;
    for (colnum = 0; colnum<77; colnum++) {
        r = 255-(colnum*255/76);
        g = (colnum*510/76);
        b = (colnum*255/76);
        if (g>255) g = 510-g;
        printf "\033[48;2;%d;%d;%dm", r,g,b;
        printf "\033[38;2;%d;%d;%dm", 255-r,255-g,255-b;
        printf "%s\033[0m", substr(s,colnum+1,1);
    }
    printf "\n";
}'

如下是在iTerm.app中的运行结果：

如下图是在Terminal.app中的运行结果，目前应该是只支持 256 色，相比而言，iTerm.app的色彩支持更好：

Terminal escape sequences 说明

The ANSI/VT100 terminals and terminal emulators are not just able to display black and white text ; they can display colors and formatted texts thanks to escape sequences. Those sequences are composed of the Escape character (often represented by "^[" or "<Esc>") followed by some other characters: "<Esc>[FormatCodem".

In Bash, the <Esc> character can be obtained with the following syntaxes:

1. \e
2. \033
3. \x1B

Foreground (text)

For using one of the 256 colors on the foreground (text color), the control sequence is "<Esc>[38;5;ColorNumberm" where ColorNumber is one of the following colors:

Background

For using one of the 256 colors on the background, the control sequence is "<Esc>[48;5;ColorNumberm" where ColorNumber is one of the following colors:

详细说明可参考 Bash Colors 和 ANSI escape code。

24bit true colour

24bit 彩色通过 RBG 方式明确指定，其中 fg 为 38，bg 为 48。

printf "\x1b[${fg};2;${red};${green};${blue}m\n"
printf "\x1b[${bg};2;${red};${green};${blue}m\n"

以下结果输出为白色的则表示不支持 24bit 颜色，如下图是在 iTerm.app 中输出的真彩结果：

24bit true colors support in neovim and vim

1. neovim - since commit 8dd415e887923f99ab5daaeba9f0303e173dd1aa; need to set termguicolors to enable true color.
2. vim - (from 7.4.1770) since commit 8a633e3427b47286869aa4b96f2bfc1fe65b25cd; need to set termguicolors to enable true color.

打印 256 色到控制台

如下脚本，会输出 256 色示例到控制台，显示对应颜色和色号：

 curl -s https://gist.githubusercontent.com/HaleTom/89ffe32783f89f403bba96bd7bcd1263/raw/ | bash

控制台输出如下图：

上面输出的结果中第一行的 16 色(3/4bit)分别对应 8 个背景色和 8 个前景色，可以参考文章说明：table for 16-color terminal escape sequences

ANSI 16 colors escape codes

8 背景色和 8 前景色以及粗细字体组合:

bash 前景色和背景色 256 色输出示例

#!/bin/bash

for i in {0..255}; do printf '\e[48;5;%dm%3d ' $i $i; (((i+3) % 18)) || printf '\e[0m\n\t'; done

printf '\e[0m\n'
printf '\n\t'

for i in {0..255}; do printf '\x1b[38;5;%dm%3d ' $i $i; (((i+3) % 18)) || printf '\x1b[0m\n\t'; done
printf '\n'

zsh 中前景色和背景色设置模式说明

 man zshmisc

上述命令输出内容摘录与前景色后景色设置有关的部分说明如下：

# Visual effects
    # %B (%b)
        # Start (stop) boldface mode.

    # %E     Clear to end of line.

    # %U (%u)
        # Start (stop) underline mode.

    # %S (%s)
        # Start (stop) standout mode.

    # %F (%f)
        # Start (stop) using a different foreground colour, if supported by the terminal.  The colour may be  specified  two  ways:
        # either as a numeric argument, as normal, or by a sequence in braces following the %F, for example %F{red}.  In the latter
        # case the values allowed are as described for the fg zle_highlight attribute; see  Character  Highlighting  in  zshzle(1).
        # This means that numeric colours are allowed in the second format also.

    # %K (%k)
        # Start (stop) using a different bacKground colour.  The syntax is identical to that for %F and %f.

    # %{...%}
        # Include  a  string  as  a  literal  escape sequence.  The string within the braces should not change the cursor position.
        # Brace pairs can nest.

        # A positive numeric argument between the % and the { is treated as described for %G below.

    # %G  Within a %{...%} sequence, include a `glitch': that is, assume that a single character width will  be  output.   This  is
        # useful  when outputting characters that otherwise cannot be correctly handled by the shell, such as the alternate charac-
        # ter set on some terminals.  The characters in question can be included within a %{...%} sequence together with the appro-
        # priate  number  of  %G sequences to indicate the correct width.  An integer between the `%' and `G' indicates a character
        # width other than one.  Hence %{seq%2G%} outputs seq and assumes it takes up the width of two standard characters.

        # Multiple uses of %G accumulate in the obvious fashion; the position of the %G is unimportant.  Negative integers are  not
        # handled.

        # Note that when prompt truncation is in use it is advisable to divide up output into single characters within each %{...%}
        # group so that the correct truncation point can be found.

zsh 前景色和背景色 256 色输出示例

#!/usr/bin/env zsh

# You can switch foreground and background colors with the standout mode %S (%s).
# As you can see, it does not matter in which order the colors and modes (works the same for boldface and underline modes) are set.
# You can set a foreground color with %F{color} before or after starting standout mode with %S, it is just used as background after %S until you stop standout mode with %s.
print -P $'\t unchanged output colors'
print -P $'\t%f%k default colors %S standout mode %s'
print -P $'\t%F{blue}%K{red} blue on red %f%k'
print -P $'\t%S%F{blue}%K{red} red on blue %s blue on red %f%k'
print -P $'\t%K{default}%F{blue}%Sdefault background on blue %s%f%k'
print -P $'\t%K{red}%F{default}%S red on default foreground %f%k%s'

powerlevel9k 输出前景色和背景色

上面这个前景色和背景色输出示例，在oh-my-zsh主题powerlevel9k中有个帮助方法，可以用来查看类似的效果，命令如下所示：

 getColorCode foreground
 getColorCode background

上述二个命令输出截图部分如下：

scripts source code

下面是一些在命令行控制台输出颜色的 bash 或者 zsh 脚本源码。

#!/usr/bin/env bash

# prints a color table of 8bg * 8fg * 2 states (regular/bold)
echo
echo Table for 16-color terminal escape sequences.
echo Replace ESC with \\033 in bash.
echo
echo "Background | Foreground colors"
echo "---------------------------------------------------------------------"
for((bg=40;bg<=47;bg++)); do
    for((bold=0;bold<=1;bold++)) do
        echo -en "\033[0m"" ESC[${bg}m   | "
        for((fg=30;fg<=37;fg++)); do
            if [ $bold == "0" ]; then
                echo -en "\033[${bg}m\033[${fg}m [${fg}m  "
            else
                echo -en "\033[${bg}m\033[1;${fg}m [1;${fg}m"
            fi
        done
        echo -e "\033[0m"
    done
    echo "--------------------------------------------------------------------- "
done
echo

#!/usr/bin/env bash

# Tom Hale, 2016. MIT Licence.
# Print out 256 colours, with each number printed in its corresponding colour
# See http://askubuntu.com/questions/821157/print-a-256-color-test-pattern-in-the-terminal/821163#821163

set -eu # Fail on errors or undeclared variables

printable_colours=256

# Return a colour that contrasts with the given colour
# Bash only does integer division, so keep it integral
function contrast_colour {
    local r g b luminance
    colour="$1"

    if (( colour < 16 )); then # Initial 16 ANSI colours
        (( colour == 0 )) && printf "15" || printf "0"
        return
    fi

    # Greyscale # rgb_R = rgb_G = rgb_B = (number - 232) * 10 + 8
    if (( colour > 231 )); then # Greyscale ramp
        (( colour < 244 )) && printf "15" || printf "0"
        return
    fi

    # All other colours:
    # 6x6x6 colour cube = 16 + 36*R + 6*G + B  # Where RGB are [0..5]
    # See http://stackoverflow.com/a/27165165/5353461

    # r=$(( (colour-16) / 36 ))
    g=$(( ((colour-16) % 36) / 6 ))
    # b=$(( (colour-16) % 6 ))

    # If luminance is bright, print number in black, white otherwise.
    # Green contributes 587/1000 to human perceived luminance - ITU R-REC-BT.601
    (( g > 2)) && printf "0" || printf "15"
    return

    # Uncomment the below for more precise luminance calculations

    # # Calculate percieved brightness
    # # See https://www.w3.org/TR/AERT#color-contrast
    # # and http://www.itu.int/rec/R-REC-BT.601
    # # Luminance is in range 0..5000 as each value is 0..5
    # luminance=$(( (r * 299) + (g * 587) + (b * 114) ))
    # (( $luminance > 2500 )) && printf "0" || printf "15"
}

# Print a coloured block with the number of that colour
function print_colour {
    local colour="$1" contrast
    contrast=$(contrast_colour "$1")
    printf "\e[48;5;%sm" "$colour"                # Start block of colour
    printf "\e[38;5;%sm%3d" "$contrast" "$colour" # In contrast, print number
    printf "\e[0m "                               # Reset colour
}

# Starting at $1, print a run of $2 colours
function print_run {
    local i
    printf "  "
    for (( i = "$1"; i < "$1" + "$2" && i < printable_colours; i++ )) do
        print_colour "$i"
    done
    printf "  "
}

# Print blocks of colours
function print_blocks {
    local start="$1" i
    local end="$2" # inclusive
    local block_cols="$3"
    local block_rows="$4"
    local blocks_per_line="$5"
    local block_length=$((block_cols * block_rows))

    # Print sets of blocks
    for (( i = start; i <= end; i += (blocks_per_line-1) * block_length )) do
        printf "\n" # Space before each set of blocks
        # For each block row
        for (( row = 0; row < block_rows; row++ )) do
            # Print block columns for all blocks on the line
            for (( block = 0; block < blocks_per_line; block++ )) do
                print_run $(( i + (block * block_length) )) "$block_cols"
            done
            (( i += block_cols )) # Prepare to print the next row
            printf "\n"
        done
    done
}

printf "\n"
print_run 0 16 # The first 16 colours are spread over the whole spectrum
printf "\n"
print_blocks 16 231 6 6 3 # 6x6x6 colour cube between 16 and 231 inclusive
print_blocks 232 255 12 2 1 # Not 50, but 24 Shades of Grey

#!/usr/bin/env bash

for i in {0..255} ; do printf "\x1b[38;5;${i}mcolour${i}\x1b[0m\n"; done

printf '\e[0m\n'

for i in {0..255} ; do printf "\e[48;5;${i}mcolour${i}\e[0m\n"; done

#!/usr/bin/env bash

# This program is free software. It comes without any warranty, to
# the extent permitted by applicable law. You can redistribute it
# and/or modify it under the terms of the Do What The Fuck You Want
# To Public License, Version 2, as published by Sam Hocevar. See
# http://sam.zoy.org/wtfpl/COPYING for more details.

for fgbg in 38 48 ; do #Foreground/Background
    for color in {0..255} ; do #Colors
        #Display the color
        echo -en "\e[${fgbg};5;${color}m ${color}\t\e[0m"
        #Display 10 colors per lines
        if [ $((($color + 1) % 10)) == 0 ] ; then
            echo #New line
        fi
    done
    echo #New line
done

exit 0

#!/usr/bin/env bash

# This program is free software. It comes without any warranty, to
# the extent permitted by applicable law. You can redistribute it
# and/or modify it under the terms of the Do What The Fuck You Want
# To Public License, Version 2, as published by Sam Hocevar. See
# http://sam.zoy.org/wtfpl/COPYING for more details.

#Background
for clbg in {40..47} {100..107} 49 ; do
    #Foreground
    for clfg in {30..37} {90..97} 39 ; do
        #Formatting
        for attr in 0 1 2 4 5 7 ; do
            #Print the result
            echo -en "\e[${attr};${clbg};${clfg}m ^[${attr};${clbg};${clfg}m \e[0m"
        done
        echo #Newline
    done
done

exit 0

#!/usr/bin/env zsh

for code ({000..255}) print -P -- "$code: %F{$code}This is how your text would look like%f"
for code ({000..255}) print -P -- "$code: %K{$code}This is how your background would look like%k"

#!/usr/bin/env zsh

################################################################
# vim:ft=zsh ts=2 sw=2 sts=2 et fenc=utf-8
# Color functions
# This file holds some color-functions for
# the powerlevel9k-ZSH-theme
# https://github.com/bhilburn/powerlevel9k
################################################################

typeset -gAh __P9K_COLORS
# https://jonasjacek.github.io/colors/
# use color names by default to allow dark/light themes to adjust colors based on names
__P9K_COLORS=(
  black             000
  red               001
  green             002
  yellow            003
  blue              004
  magenta           005
  cyan              006
  white             007
  grey              008
  maroon            009
  lime              010
  olive             011
  navy              012
  fuchsia           013
  purple            013
  aqua              014
  teal              014
  silver            015
  grey0             016
  navyblue          017
  darkblue          018
  blue3             019
  blue3             020
  blue1             021
  darkgreen         022
  deepskyblue4      023
  deepskyblue4      024
  deepskyblue4      025
  dodgerblue3       026
  dodgerblue2       027
  green4            028
  springgreen4      029
  turquoise4        030
  deepskyblue3      031
  deepskyblue3      032
  dodgerblue1       033
  green3            034
  springgreen3      035
  darkcyan          036
  lightseagreen     037
  deepskyblue2      038
  deepskyblue1      039
  green3            040
  springgreen3      041
  springgreen2      042
  cyan3             043
  darkturquoise     044
  turquoise2        045
  green1            046
  springgreen2      047
  springgreen1      048
  mediumspringgreen 049
  cyan2             050
  cyan1             051
  darkred           052
  deeppink4         053
  purple4           054
  purple4           055
  purple3           056
  blueviolet        057
  orange4           058
  grey37            059
  mediumpurple4     060
  slateblue3        061
  slateblue3        062
  royalblue1        063
  chartreuse4       064
  darkseagreen4     065
  paleturquoise4    066
  steelblue         067
  steelblue3        068
  cornflowerblue    069
  chartreuse3       070
  darkseagreen4     071
  cadetblue         072
  cadetblue         073
  skyblue3          074
  steelblue1        075
  chartreuse3       076
  palegreen3        077
  seagreen3         078
  aquamarine3       079
  mediumturquoise   080
  steelblue1        081
  chartreuse2       082
  seagreen2         083
  seagreen1         084
  seagreen1         085
  aquamarine1       086
  darkslategray2    087
  darkred           088
  deeppink4         089
  darkmagenta       090
  darkmagenta       091
  darkviolet        092
  purple            093
  orange4           094
  lightpink4        095
  plum4             096
  mediumpurple3     097
  mediumpurple3     098
  slateblue1        099
  yellow4           100
  wheat4            101
  grey53            102
  lightslategrey    103
  mediumpurple      104
  lightslateblue    105
  yellow4           106
  darkolivegreen3   107
  darkseagreen      108
  lightskyblue3     109
  lightskyblue3     110
  skyblue2          111
  chartreuse2       112
  darkolivegreen3   113
  palegreen3        114
  darkseagreen3     115
  darkslategray3    116
  skyblue1          117
  chartreuse1       118
  lightgreen        119
  lightgreen        120
  palegreen1        121
  aquamarine1       122
  darkslategray1    123
  red3              124
  deeppink4         125
  mediumvioletred   126
  magenta3          127
  darkviolet        128
  purple            129
  darkorange3       130
  indianred         131
  hotpink3          132
  mediumorchid3     133
  mediumorchid      134
  mediumpurple2     135
  darkgoldenrod     136
  lightsalmon3      137
  rosybrown         138
  grey63            139
  mediumpurple2     140
  mediumpurple1     141
  gold3             142
  darkkhaki         143
  navajowhite3      144
  grey69            145
  lightsteelblue3   146
  lightsteelblue    147
  yellow3           148
  darkolivegreen3   149
  darkseagreen3     150
  darkseagreen2     151
  lightcyan3        152
  lightskyblue1     153
  greenyellow       154
  darkolivegreen2   155
  palegreen1        156
  darkseagreen2     157
  darkseagreen1     158
  paleturquoise1    159
  red3              160
  deeppink3         161
  deeppink3         162
  magenta3          163
  magenta3          164
  magenta2          165
  darkorange3       166
  indianred         167
  hotpink3          168
  hotpink2          169
  orchid            170
  mediumorchid1     171
  orange3           172
  lightsalmon3      173
  lightpink3        174
  pink3             175
  plum3             176
  violet            177
  gold3             178
  lightgoldenrod3   179
  tan               180
  mistyrose3        181
  thistle3          182
  plum2             183
  yellow3           184
  khaki3            185
  lightgoldenrod2   186
  lightyellow3      187
  grey84            188
  lightsteelblue1   189
  yellow2           190
  darkolivegreen1   191
  darkolivegreen1   192
  darkseagreen1     193
  honeydew2         194
  lightcyan1        195
  red1              196
  deeppink2         197
  deeppink1         198
  deeppink1         199
  magenta2          200
  magenta1          201
  orangered1        202
  indianred1        203
  indianred1        204
  hotpink           205
  hotpink           206
  mediumorchid1     207
  darkorange        208
  salmon1           209
  lightcoral        210
  palevioletred1    211
  orchid2           212
  orchid1           213
  orange1           214
  sandybrown        215
  lightsalmon1      216
  lightpink1        217
  pink1             218
  plum1             219
  gold1             220
  lightgoldenrod2   221
  lightgoldenrod2   222
  navajowhite1      223
  mistyrose1        224
  thistle1          225
  yellow1           226
  lightgoldenrod1   227
  khaki1            228
  wheat1            229
  cornsilk1         230
  grey100           231
  grey3             232
  grey7             233
  grey11            234
  grey15            235
  grey19            236
  grey23            237
  grey27            238
  grey30            239
  grey35            240
  grey39            241
  grey42            242
  grey46            243
  grey50            244
  grey54            245
  grey58            246
  grey62            247
  grey66            248
  grey70            249
  grey74            250
  grey78            251
  grey82            252
  grey85            253
  grey89            254
  grey93            255
)

function termColors() {
  if [[ $POWERLEVEL9K_IGNORE_TERM_COLORS == true ]]; then
    return
  fi

  local term_colors

  if which tput &>/dev/null; then
    term_colors=$(tput colors)
  else
    term_colors=$(echotc Co)
  fi
  if (( ! $? && ${term_colors:-0} < 256 )); then
    print -P "%F{red}WARNING!%f Your terminal appears to support fewer than 256 colors!"
    print -P "If your terminal supports 256 colors, please export the appropriate environment variable"
    print -P "_before_ loading this theme in your \~\/.zshrc. In most terminal emulators, putting"
    print -P "%F{blue}export TERM=\"xterm-256color\"%f at the top of your \~\/.zshrc is sufficient."
  fi
}

# get the proper color code if it does not exist as a name.
function getColor() {
  # If Color is not numerical, try to get the color code.
  if [[ "$1" != <-> ]]; then
    1=$(getColorCode $1)
  fi
  echo -n "$1"
}

# empty paramenter resets (stops) background color
function backgroundColor() {
  echo -n "%K{$(getColor $1)}"
}

# empty paramenter resets (stops) foreground color
function foregroundColor() {
  echo -n "%F{$(getColor $1)}"
}

# Get numerical color codes. That way we translate ANSI codes
# into ZSH-Style color codes.
function getColorCode() {
  # Early exit: Check if given value is already numerical
  if [[ "$1" == <-> ]]; then
    # Pad color with zeroes
    echo -n "${(l:3::0:)1}"
    return
  fi

  local colorName="${1}"
  # Check if value is none with any case.
  if [[ "${(L)colorName}" == "none" ]]; then
      echo -n 'none'
  elif [[ "${colorName}" == "foreground"  ]]; then
      # for testing purposes in terminal
      # call via `getColorCode foreground`
      for i in "${([email protected])__P9K_COLORS}"; do
          print -P "$(foregroundColor $i)$(getColor $i) - $i%f"
      done
  elif [[ "${colorName}" == "background"  ]]; then
      # call via `getColorCode background`
      for i in "${([email protected])__P9K_COLORS}"; do
          print -P "$(backgroundColor $i)$(getColor $i) - $i%k"
      done
  else
      # Strip eventual "bg-" prefixes
      colorName=${colorName#bg-}
      # Strip eventual "fg-" prefixes
      colorName=${colorName#fg-}
      # Strip eventual "br" prefixes ("bright" colors)
      colorName=${colorName#br}
      echo -n $__P9K_COLORS[$colorName]
  fi
}

# Check if two colors are equal, even if one is specified as ANSI code.
function isSameColor() {
  if [[ "$1" == "NONE" || "$2" == "NONE" ]]; then
    return 1
  fi

  local color1=$(getColorCode "$1")
  local color2=$(getColorCode "$2")

  return $(( color1 != color2 ))
}

References

1. 256 COLORS - CHEAT SHEET
2. table for 16-color terminal escape sequences
3. Bash Colors
4. Xterm 256color chart SVG
5. Xterm 256color chart PNG
6. zsh 256colors: default background color as foreground color
7. colors.zsh of powerlevel9k
8. ANSI escape code
9. How to change the output color of echo in Linux
10. Print a 256-color test pattern in the terminal
11. Colours in terminal