A script to download and scale svg icons from simple-icons.org, before converting them to png, and outputing a SassScript (CSS) fragment with background colour information

simple-icons-png.sh

#!/bin/bash

# sudo apt-get install jq librsvg2-bin imagemagick
# Move each vector image to the origin, scale, and move it back again
# Outputs a SIZExSIZE transparent png 
# Also outputs scss (Sassy CSS) fragments, unless "-q" is an input argument

SIZE=48
SCALE_FACTOR=0.65
ARGS=("$@")
NARGS=$#
SI=simple-icons
SI_URL=https://raw.githubusercontent.com/$SI/$SI/develop/_data/$SI.json
ICON_URL=https://simpleicons.org/icons

if [[ $NARGS -eq 0 ]]; then
  RED='\033[0;31m'
  NC='\033[0m' # No colour
  echo -en "${RED}error:${NC} "
  echo "  please provide space-delimited SVG icon names without extension. e.g:"
  echo "  bash simple-icons-png.sh strava bitbucket"
  echo "  If you don't want the scss colour information use -q (quiet):"
  echo "  bash simple-icons-png.sh strava bitbucket -q"
  echo "  ...or if an icon's simple-icons.json entry contains spaces, use quotes:"
  echo "  bash simple-icons-png.sh strava bitbucket \"Adobe Acrobat Reader\""
  exit -1
fi

function wget_scale_svg_png()
{
for N in "${ARGS[@]}"
do
  if [ "$N" == "-q" ]; then continue; fi
  S_="${N// /}"   # Remove spaces
  L_="${S_,,}"    # Lower case
  wget -q $ICON_URL/$L_.svg
  X=$(identify "$L_.svg" | awk -F ' ' '{print $3}' | awk -F 'x' '{print $1}')
  X=$((X / 2))
  SCALE_STR="translate(${X},${X}) scale(${SCALE_FACTOR}) translate(-${X},-${X})"
# Double quotes are needed due to SCALE_STR's use of ${X}
# The odd sed formation ensures only the first occurrence of > is replaced
  sed "0,/>/s//><g transform=\"${SCALE_STR}\">/" "$L_.svg" |
  sed 's/<\/svg>/<\/g><\/svg>/g' > ${L_}-${SCALE_FACTOR}.svg
  OUT=${L_}-${SIZE}.png   #OUT=${L_}-${SIZE}-${SCALE_FACTOR}.png
  rsvg-convert -h ${SIZE} ${L_}-${SCALE_FACTOR}.svg > $OUT
  convert $OUT -negate $OUT
  cp $OUT $OLDPWD
done
}


function scss_colour_out()
{
  wget -q $SI_URL
  for N in "${ARGS[@]}"
  do
    C=$(jq '.icons[] | select(.title | match('"\"$N\""';"i")) .hex' $SI.json)
    S_="${N// /}"   # Remove spaces
    L_="${S_,,}"    # Lower case
    C_="${C//\"/}"  # Remove quotes
    echo -e ".ico-$L_ { @include get-ico-image($L_); background-color: #$C_; }"
  done
}

cd `mktemp -d`

for N in "${ARGS[@]}"
do
  if [ "$N" == "-q" ]; then QUIET=1; fi
done

if [ -z "$QUIET" ]; then scss_colour_out; fi 

wget_scale_svg_png