bash script to "snap" the current terminal emulator to an aspect ratio

snap.sh

#!/bin/bash

## bash script to "snap" the current terminal emulator to an aspect
## ratio maintaining either the width or the height. note that your
## terminal will actually snap to the closest size that has no
## partial character cells

ar="16/10"             ## set your aspect ratio here
ar=$(bc -l <<< "$ar")

calcs() {
    local success=false
    exec < /dev/tty
    local oldstty=$(stty -g)
    stty raw -echo min 0
    echo -e "\e[14t" >/dev/tty

    if IFS=';' read -r -d '\' -a color ; then
	h=${color[1]}; echo $h
	w=${color[2]%%t*}; echo $w
	success=true;    stty $oldstty
	return 0
    fi
    stty $oldstty
    return 0
    $success
}

## snap to aspect ratio maintaining width
snapx() {
    read -r -a p <<< $(calcs)
    if [ $? == 0 ]; then
	local h=${p[0]}; local w=${p[1]}
	echo -e "[4;$(printf %0.f $(bc -l <<< "$w / $ar"));${w}t"
	return 0
    fi
    return 1
}

## snap to aspect ratio maintaining height
snapy() {
    read -r -a p <<< $(calcs)
    if [ $? == 0 ]; then
	local h=${p[0]}; local w=${p[1]}
	echo -e "[4;${h};$(printf %0.f $(bc -l <<< "$h * $ar"))t"
	return 0
    fi
    return 1
}

case $0 in
    snapx|*/snapx)
	snapx
	exit $?
	;;
    snapy|*/snapy)
	snapy
	exit $?
	;;
    *)
	echo "Usage error: must be called as snapx or snapy" || exit 1
	;;
esac