Added two more terminal color related scripts.

term_colors/24-bit-color.sh

@@ -0,0 +1,100 @@
+#!/bin/bash
+# This file was originally taken from iterm2 https://github.com/gnachman/iTerm2/blob/master/tests/24-bit-color.sh
+#
+#   This file echoes a bunch of 24-bit color codes
+#   to the terminal to demonstrate its functionality.
+#   The foreground escape sequence is ^[38;2;<r>;<g>;<b>m
+#   The background escape sequence is ^[48;2;<r>;<g>;<b>m
+#   <r> <g> <b> range from 0 to 255 inclusive.
+#   The escape sequence ^[0m returns output to default
+
+setBackgroundColor()
+{
+    #printf '\x1bPtmux;\x1b\x1b[48;2;%s;%s;%sm' $1 $2 $3
+    printf '\x1b[48;2;%s;%s;%sm' $1 $2 $3
+}
+
+resetOutput()
+{
+    echo -en "\x1b[0m\n"
+}
+
+# Gives a color $1/255 % along HSV
+# Who knows what happens when $1 is outside 0-255
+# Echoes "$red $green $blue" where
+# $red $green and $blue are integers
+# ranging between 0 and 255 inclusive
+rainbowColor()
+{ 
+    let h=$1/43
+    let f=$1-43*$h
+    let t=$f*255/43
+    let q=255-t
+
+    if [ $h -eq 0 ]
+    then
+        echo "255 $t 0"
+    elif [ $h -eq 1 ]
+    then
+        echo "$q 255 0"
+    elif [ $h -eq 2 ]
+    then
+        echo "0 255 $t"
+    elif [ $h -eq 3 ]
+    then
+        echo "0 $q 255"
+    elif [ $h -eq 4 ]
+    then
+        echo "$t 0 255"
+    elif [ $h -eq 5 ]
+    then
+        echo "255 0 $q"
+    else
+        # execution should never reach here
+        echo "0 0 0"
+    fi
+}
+
+for i in `seq 0 127`; do
+    setBackgroundColor $i 0 0
+    echo -en " "
+done
+resetOutput
+for i in `seq 255 -1 128`; do
+    setBackgroundColor $i 0 0
+    echo -en " "
+done
+resetOutput
+
+for i in `seq 0 127`; do
+    setBackgroundColor 0 $i 0
+    echo -n " "
+done
+resetOutput
+for i in `seq 255 -1 128`; do
+    setBackgroundColor 0 $i 0
+    echo -n " "
+done
+resetOutput
+
+for i in `seq 0 127`; do
+    setBackgroundColor 0 0 $i
+    echo -n " "
+done
+resetOutput
+for i in `seq 255 -1 128`; do
+    setBackgroundColor 0 0 $i
+    echo -n " "
+done
+resetOutput
+
+for i in `seq 0 127`; do
+    setBackgroundColor `rainbowColor $i`
+    echo -n " "
+done
+resetOutput
+for i in `seq 255 -1 128`; do
+    setBackgroundColor `rainbowColor $i`
+    echo -n " "
+done
+resetOutput

term_colors/xterm-color-count.sh

@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+
+trap 'tput sgr0' exit		# Clean up even if user hits ^C
+
+function setfg () {
+    printf '\e[38;5;%dm' $1
+}
+function setbg () {
+    printf '\e[48;5;%dm' $1
+}
+function showcolors() {
+    # Given an integer, display that many colors
+    for ((i=0; i<$1; i++))
+    do
+	printf '%4d ' $i
+	setbg $i
+	tput el
+	tput sgr0
+	echo
+    done
+    tput sgr0 el
+}
+
+
+### Main starts here
+
+# First, test if terminal supports OSC 4 at all.
+printf '\e]4;%d;?\a' 0
+read -d $'\a' -s -t 0.1 </dev/tty
+if [ -z "$REPLY" ]
+then
+    # OSC 4 not supported, so we'll fall back to terminfo
+    max=$(tput colors)
+else
+    # OSC 4 is supported, so use it for a binary search
+    min=0
+    max=256
+    while [[ $((min+1)) -lt $max ]]
+    do
+	i=$(( (min+max)/2 ))
+	printf '\e]4;%d;?\a' $i
+	read -d $'\a' -s -t 0.1 </dev/tty
+	if [ -z "$REPLY" ]
+	then
+            max=$i
+	else
+	    min=$i
+	fi
+    done
+fi
+
+
+# If -v is given, show all the colors
+case ${1-none} in
+    none)
+	echo $max
+	;;
+    -v)
+	showcolors $max
+	;;
+    *)
+	if [[ "$1" -gt 0 ]]; then
+	    showcolors $1
+	else
+	    echo $max
+	fi
+	;;
+esac | less --raw-control-chars --QUIT-AT-EOF --no-init