This sets me up to do more adaptive colours with the prompt.

Colours now can use 24-bit colour sequences.

A script drives the generation of SGR codes...  Now I just have
to integrate this into `tcshrc.prompt.final`, for dynamic updating.
This commit is contained in:
2022-06-04 01:22:12 -04:00
parent 328c1c13e3
commit 856fd35085
2 changed files with 239 additions and 0 deletions

214
bin/__hex_to_ansi Executable file
View File

@ -0,0 +1,214 @@
#!/usr/bin/env bash
# This script will take an HTML compatible hex colour string and turn it into
# a terminal sequence for true colour and other formats which best approximate
# its colour value.
debug=0
if [ ${1} == "fg" ]
then
background=0
elif [ ${1} == "bg" ]
then
background=1
else
exit -1
fi
shift 1
use_8_bit=0
use_4_bit=0
use_3_bit=0
if [ ${1:0:5} == "ansi:" ]
then
selection=${1:5}
if (( ${selection} > 15 ))
then
exit -1
elif (( ${selection} >= 8 ))
then
use_4_bit=1
intensity_1_bit=1
legacy_3_bit=$(( ${selection} - 8 ))
else
use_3_bit=1
intensity_1_bit=0
legacy_3_bit=$(( ${selection} ))
fi
elif [ ${1:0:4} == "ext:" ]
then
use_8_bit=1
selection=${1:4}
if (( ${selection} > 255 ))
then
exit -1
else
ext_8_bit=${selection}
fi
else # Parse the hex and do the thing...
# First split off the red, green, and blue components...
red_hex=${1:0:2}
green_hex=${1:2:2}
blue_hex=${1:4:2}
# Convert to decimal...
red_dec=$((16#${red_hex}))
green_dec=$((16#${green_hex}))
blue_dec=$((16#${blue_hex}))
if (( ${debug} != 0 ))
then
echo "Red: $red_dec"
echo "Green: $green_dec"
echo "Blue: $blue_dec"
fi
# Now compute the rest of the stuff...
# We probably don't have to compute all the unused color states. We only have to compute
# the color state we're signed up for by CSHENV_TERMINAL_COLORS... but whatever...
# We round up by 128 points of colour, so that if we're above a certain intensity, we get the top
# bit set.
red_1_bit=$(( ( ( ${red_dec} + 128 ) >> 8 ) & 1 ))
green_1_bit=$(( ( ( ${green_dec} + 128 ) >> 8 ) & 1 ))
blue_1_bit=$(( ( ( ${blue_dec} + 128 ) >> 8 ) & 1 ))
intensity_1_bit=0
# If we can support an intensity bit, we'll turn that on too...
# But we're going to stop using bold to set the colour "intense"
# We'll use the 9x and 10x forms...
if (( ${red_dec} >= 192 || ${green_dec} >= 192 || ${blue_dec} >= 192 ))
then
intensity_1_bit=1
fi
if (( ${debug} != 0 ))
then
echo "Red bit: " $red_1_bit
echo "Green bit: " $green_1_bit
echo "Blue bit: " $blue_1_bit
echo "Intensity bit: " $intensity_1_bit
fi
# This lets us combine them for a legacy colour value in the legacy colour space...
legacy_3_bit=$(( ( ${blue_1_bit} << 2 ) + ( ${green_1_bit} << 1 ) + ( ${red_1_bit} ) ))
if (( ${debug} != 0 ))
then
echo "Legacy colour: " ${legacy_3_bit} " Intensity: " ${intensity_1_bit}
fi
# Now compute an extended colour cube placement (216 colours):
red_ext_val=$(( ${red_dec} * 6 / 256 ))
green_ext_val=$(( ${green_dec} * 6 / 256 ))
blue_ext_val=$(( ${blue_dec} * 6 / 256 ))
if (( ${debug} != 0 ))
then
echo "Red ext: " ${red_ext_val}
echo "Green ext: " ${green_ext_val}
echo "Blue ext: " ${blue_ext_val}
fi
ext_8_bit=$(( 16 + 36 * ${red_ext_val} + 6 * ${green_ext_val} + ${blue_ext_val} ))
if (( ${debug} ))
then
echo "Computed 216 color cube: " ${ext_8_bit}
fi
# Check for precise greyscale, which would replace the above:
# (Note that precise greyscale is implied by a user explicitly making ALL of RGB the
# same value, thus demanding greyscale, rather than a subtle tinting...)
if (( ${red_dec} == ${green_dec} && ${green_dec} == ${blue_dec} ))
then
ext_8_bit=$(( 232 + ${red_dec} * 24 / 256 ))
fi
if (( ${debug} ))
then
echo "Computed 256 color choice, after applying greyscale scan: " ${ext_8_bit}
fi
# Check for SPECIFIC white and black and grey:
# The half-saturation, no saturation, and full saturation values are mapped
# to specific points in the legacy set. (This may be ill-advised as a manually
# built reverse video terminal setting through colour mapping may make it so that
# we wind up in la-la land. Perhaps the better way is to find the head and tail
# points in the 6x6x6 colour cube.)
#
# TODO: Only map the head and tail of the colour cube.
if (( ${red_dec} == ${green_dec} && ${green_dec} == ${blue_dec} ))
then
if (( ${red_dec} == 0 ))
then
ext_8_bit=0
elif (( ${red_dec} == 255 ))
then
ext_8_bit=15
elif (( ${red_dec} == 128 ))
then
ext_8_bit=8
elif (( ${red_dec} == 192 ))
then
ext_8_bit=7
fi
fi
if (( ${debug} ))
then
echo "Computed 256 color choice, after applying white and black scan: " ${ext_8_bit}
fi
# We do NOT check for the base colours precisely. Since those 16 can be custom mapped by your terminal emulator, you just pass `ansi:0` thru
# `ansi:15` to select them by ID. Or use `ext:0` thru `ext:255` to select a specific extended colour. Otherwise, we now generate the true-colour
# result:
fi
# Must only be set if terminal colors are reduced...
if [[ -v CSHENV_TERMINAL_COLORS ]]
then
if (( ${CSHENV_TERMINAL_COLORS} == 256 ))
then
use_8_bit=1
elif (( ${CSHENV_TERMINAL_COLORS} == 16 ))
then
use_4_bit=1
elif (( ${CSHENV_TERMINAL_COLORS} == 8 ))
then
use_3_bit=1
else
exit -1
fi
fi
command_color=30
if (( ${use_3_bit} ))
then
basecolor=$(( ${command_color} ))
printf $(( ${basecolor} + ${legacy_3_bit} ))
elif (( ${use_4_bit} ))
then
command_color=$(( ${command_color} + ${intensity_1_bit} * 60 ))
basecolor=$(( ${command_color} + ${background}*10 ))
printf $(( ${basecolor} + ${legacy_3_bit} ))
elif (( ${use_8_bit} ))
then
basecolor=$(( 8 + ${command_color} + ${background}*10 ))
printf "${basecolor};5;${ext_8_bit}"
else
basecolor=$(( 8 + ${command_color} + ${background}*10 ))
printf "${basecolor};2;${red_dec};${green_dec};${blue_dec}"
fi
exit 0

View File

@ -4,6 +4,7 @@
set csi='['
# Legacy 3-bit ANSI Forms:
set ansi_bright='1'
set ansi_dim='0'
set ansi_color='m'
@ -34,6 +35,10 @@ set magenta="$csi$ansi_magenta$ansi_color"
set cyan="$csi$ansi_cyan$ansi_color"
set white="$csi$ansi_white$ansi_color"
# Bright and Dim rely upon the console's setting of colour intensity paired
# to boldness intensity. For better colour choices, it's better to use
# extended colours or true colours.
set dim_black="$csi$ansi_dim;$ansi_black$ansi_color"
@ -55,6 +60,26 @@ set bright_magenta="$csi$ansi_bright;$ansi_magenta$ansi_color"
set bright_cyan="$csi$ansi_bright;$ansi_cyan$ansi_color"
set bright_white="$csi$ansi_bright;$ansi_white$ansi_color"
# Also somewhat legacy are the extended colours... so I'm not implementing them.
# Instead, I'll use my script which does math on the 6 char hex string you use in
# colors...
#################################
# Extended 8-bit colour Support #
#################################
#######################
# True colour support #
#######################
# The idea behind a true colour variable is that you run: `color_from_hex ff0077` and it expands to
# a proper colour sequence for a 24-bit color. The shell script which computes these will also attempt to
# compute a rounded version of your color for use with 8-bit color and a weaker rounded form for use
# with 3 and 4 bit color.
# You process true colour by evaluating `__make_color_sequence` on the environment variable.
alias __make_color_sequence ${CSHENV_DIR}/bin/__hex_to_ansi
###########################
# vim:filetype=tcsh