diff --git a/home/.config/shell/aliases b/home/.config/shell/aliases index 18911f1..9db8d44 100755 --- a/home/.config/shell/aliases +++ b/home/.config/shell/aliases @@ -217,7 +217,6 @@ alias path='echo -e ${PATH//:/\\n}' # Print each PATH entry on a separate line alias unsudo='sudo -k' # Reset sudo timeout (sudo will require password) alias vimwiki='vim -c VimwikiIndex' # Open vimwiki index alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"' -alias colors-256='curl -s https://gist.githubusercontent.com/HaleTom/89ffe32783f89f403bba96bd7bcd1263/raw/ | bash' # Show color table alias tty-clock='tty-clock -Ssc' # Terminal clock screensaver alias rick='curl -s -L https://raw.githubusercontent.com/ItsDrike/rickrollrc/master/roll.sh| bash' # Terminal rickroll diff --git a/home/.local/bin/scripts/colors-256 b/home/.local/bin/scripts/colors-256 new file mode 100755 index 0000000..109fba1 --- /dev/null +++ b/home/.local/bin/scripts/colors-256 @@ -0,0 +1,102 @@ +#!/bin/bash + +# # Print out 256 colors, with each number printed in its corresponding colour +# +# This file is uploaded on +# It was originally intended to be used as an alias that curled this URL and piped it into bash, however +# this is very unsafe as the owner can change the content of this gist at his convenience, meaning it was +# a potential security vulnerability. This is a script version of this alias to avoid this issue. +# +# The copyright for this file belongs to the original author: Tom Hale, 2016 +# This file was released under MIT license + +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 + 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 +} + +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