asaaki/README.md

## README.md

      
    Raw
  

              README.md
            
          
    (Forked fork, that works on macos, too)
Makes little scrolly text jiffs in Flywheel colors.
Prerequisites


macos: brew install fontconfig imagemagick gifsicle
Linux: sudo apt install fontconfig imagemagick gifsicle

Usage

Usage: ./yolo.sh [options] <message>

Options:

  -h                Show this help message

  -o <output.gif>   Path to output gif. Default: output.<random>.gif

  -c <color>        Choose color set, valid options are:
                    red, orange, yellow, green, blue, purple,
                    pink, black, white.  Default: black

  -d <delay>        Delay between frames. Default: 6

  -s <step>         How many pixels to step each frame. Default: 10

  -H <height>       Image height (and also the width). Default: 128

  -f <font name>    The font name. Default: helvetica

  -w                Force white text color

  -t                Force transparent background

  -r                CREATE RAINBOW ANIMATION! (only stacking multiple
                    single color GIFs into one; incl. black + white)

Examples

$ yolo.sh -c purple -o awesome.gif "That's awesome!"

Changes


RAINBOWS! YAY!
add option to use transparent background — yay!
default output file will include a short random hash, so you can quickly generate multiple scrollers without overwriting the previously generated one, because you forgot to set a different output file name.
print the output file name after generation
tries to open the file (on macos with Safari, on Linux with xdg-open)


## yolo.sh
#!/usr/bin/env bash

contains() {
  local e
  for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
  return 1
}

usage() {
  if [ "$1" != "" ]; then
    echo -e "Error: $1\n" >&2
  fi
  echo "Usage: $0 [options] <message>"
  echo
  echo "Options:"
  echo
  echo "  -h                Show this help message"
  echo
  echo "  -o <output.gif>   Path to output gif. Default: output.<random>.gif"
  echo
  echo "  -c <color>        Choose color set, valid options are:"
  echo "                    red, orange, yellow, green, blue, purple,"
  echo "                    pink, black, white.  Default: black"
  echo
  echo "  -d <delay>        Delay between frames. Default: 6"
  echo
  echo "  -s <step>         How many pixels to step each frame. Default: 10"
  echo
  echo "  -H <height>       Image height (and also the width). Default: 128"
  echo
  echo "  -f <font name>    The font name. Default: helvetica"
  echo
  echo "  -w                Force white text color"
  echo
  echo "  -t                Force transparent background"
  echo
  echo "  -r                CREATE RAINBOW ANIMATION! (only stacking multiple"
  echo "                    single color GIFs into one; incl. black + white)"
  exit 1
}

# Make a "unique" prefix for this run
PREFIX="$(head -c 32 /dev/urandom  | shasum | cut -b 1-10)"

VALID_COLORS=("red" "orange" "yellow" "green" "blue" "purple" "pink" "black" "white")
COLOR="black"
OUTPUT="output.$PREFIX.gif"
FONT_NAME="helvetica"
FORCE_WHITE_TEXT=0
FORCE_TRANSPARENT_BACKGROUND=0
SPEED=16
DELAY=6
HEIGHT=128
SKIP_OUTPUT_OPEN=0
RAINBOW_MODE=0

while getopts ":c:o:f:s:d:H:hwtrn" opt; do
  case $opt in
    h)
      usage
      ;;
    n)
      SKIP_OUTPUT_OPEN=1
      ;;
    r)
      RAINBOW_MODE=1
      ;;
    w)
      FORCE_WHITE_TEXT=1
      ;;
    t)
      FORCE_TRANSPARENT_BACKGROUND=1
      ;;
    c)
      if contains "$OPTARG" "${VALID_COLORS[@]}"; then
        COLOR="$OPTARG"
      else
        usage "Invalid color: $OPTARG"
      fi
      ;;
    o)
      OUTPUT="$OPTARG"
      ;;
    H)
      HEIGHT="$OPTARG"
      ;;
    f)
      FONT_NAME="$OPTARG"
      ;;
    d)
      DELAY="$OPTARG"
      ;;
    s)
      SPEED="$OPTARG"
      ;;
    \?)
      usage "Invalid option: -$OPTARG"
      ;;
    :)
      usage "Option -$OPTARG requires an argument."
      exit 1
      ;;
  esac
done

shift $((OPTIND - 1))

# Find our font before we do anything.
FONT_PATH="$( fc-match "${FONT_NAME}" -f'%{file}' )"
if [ "$FONT_PATH" == "" ]; then
  usage "Could not find '${FONT_NAME}' font. Is it installed?"
else
  echo "Using ${FONT_PATH} for ${FONT_NAME} font."
fi

MESSAGE="$*"
if [ "$MESSAGE" == "" ]; then
  usage "A message is required."
fi

if [ "$RAINBOW_MODE" == 1 ]; then
  colors=("red" "orange" "yellow" "green" "blue" "purple" "black" "white")
  declare -a files
  for color in ${colors[@]}; do
    echo "Generate color $color ..."
    file="rainbow.step.$color.gif"
    files+=($file)
    $0 -d "$DELAY" -s "$SPEED" -H "$HEIGHT" -f "$FONT_NAME" -c "$color" -t -n -o $file "$MESSAGE"
  done
  COMBINED="rainbow.$PREFIX.gif"
  convert ${files[@]} $COMBINED
  gifsicle -b -O3 -Okeep-empty -k16 $COMBINED
  echo "Final rainbow file: $COMBINED"
  exit 0
fi

case $COLOR in
  red)
    FILL="#e40303"
    BACKGROUND="#4c0000"
    ;;
  orange)
    FILL="#ff8c00"
    BACKGROUND="#562b00"
    ;;
  yellow)
    FILL="#ffed00"
    BACKGROUND="#565100"
    ;;
  green)
    FILL="#008026"
    BACKGROUND="#002705"
    ;;
  blue)
    FILL="#004dff"
    BACKGROUND="#001456"
    ;;
  purple)
    FILL="#750787"
    BACKGROUND="#23012a"
    ;;
  pink)
    FILL="#851252"
    BACKGROUND="#e0368c"
    ;;
  black)
    FILL="#111111"
    BACKGROUND="#ffffff"
    ;;
  white)
    FILL="#ffffff"
    BACKGROUND="#111111"
    ;;
esac

if [ "$FORCE_WHITE_TEXT" == 1 ]; then
  FILL="#ffffff"
fi

if [ "$FORCE_TRANSPARENT_BACKGROUND" == 1 ]; then
  echo "Using transparent background"
  BACKGROUND="transparent"
fi

# Generate image from text input
convert \
  -background "$BACKGROUND" \
  -fill "$FILL" \
  -font "$FONT_PATH" \
  -density 200 \
  -pointsize 100 \
  "label:${MESSAGE}" \
  "/tmp/${PREFIX}_label.png"

# Resize to 128px high
convert \
  -resize x${HEIGHT} \
  "/tmp/${PREFIX}_label.png" \
  "/tmp/${PREFIX}_sized.png"

# Add padding
WIDTH="$(identify -format "%[fx:w]" "/tmp/${PREFIX}_sized.png")"
CANVAS_SIZE=$((WIDTH + HEIGHT + HEIGHT + (HEIGHT / 4))) # HEIGHT in front, HEIGHT / 4 in back
# convert "/tmp/${PREFIX}_sized.png" -bordercolor $BACKGROUND -border ${HEIGHT}x0 "/tmp/${PREFIX}_padded.png"
convert \
  "/tmp/${PREFIX}_sized.png" \
  -gravity center \
  -background $BACKGROUND \
  -extent $CANVAS_SIZE \
  "/tmp/${PREFIX}_padded.png"

# Generate individual frames

STEP=$((HEIGHT / (64 / SPEED)))
OFFSET=0
I=0
LIMIT=$((CANVAS_SIZE - HEIGHT))
while [[ "$OFFSET" -lt "$LIMIT" ]]; do
  convert \
    "/tmp/${PREFIX}_padded.png" \
    -crop "${HEIGHT}x${HEIGHT}+${OFFSET}+0!" \
    "$(printf "/tmp/${PREFIX}_frame_%05d.png" $I)"
  I=$((I + 1))
  OFFSET=$((OFFSET + STEP))
done

# Compile to gif
convert \
  -delay "$DELAY" \
  -loop 0 \
  -dispose previous \
  "/tmp/${PREFIX}_frame_*.png" \
  "$OUTPUT"

# Clean up!
rm /tmp/${PREFIX}_*.png

if [ "$SKIP_OUTPUT_OPEN" == 0 ]; then
  # Optimize it
  gifsicle -b -O3 -Okeep-empty -k16 "$OUTPUT"
  echo "Your GIF is ready: $OUTPUT"
  unameOut="$(uname -s)"
  case "${unameOut}" in
      Linux*)
        xdg-open $OUTPUT
        ;;
      Darwin*)
        open -a "Safari" "$OUTPUT"
        ;;
      CYGWIN*)
        ;;
      MINGW*)
        ;;
      *)
        ;;
  esac
fi
	#!/usr/bin/env bash

	contains() {
	local e
	for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
	return 1
	}

	usage() {
	if [ "$1" != "" ]; then
	echo -e "Error: $1\n" >&2
	fi
	echo "Usage: $0 [options] <message>"
	echo
	echo "Options:"
	echo
	echo " -h Show this help message"
	echo
	echo " -o <output.gif> Path to output gif. Default: output.<random>.gif"
	echo
	echo " -c <color> Choose color set, valid options are:"
	echo " red, orange, yellow, green, blue, purple,"
	echo " pink, black, white. Default: black"
	echo
	echo " -d <delay> Delay between frames. Default: 6"
	echo
	echo " -s <step> How many pixels to step each frame. Default: 10"
	echo
	echo " -H <height> Image height (and also the width). Default: 128"
	echo
	echo " -f <font name> The font name. Default: helvetica"
	echo
	echo " -w Force white text color"
	echo
	echo " -t Force transparent background"
	echo
	echo " -r CREATE RAINBOW ANIMATION! (only stacking multiple"
	echo " single color GIFs into one; incl. black + white)"
	exit 1
	}

	# Make a "unique" prefix for this run
	PREFIX="$(head -c 32 /dev/urandom \| shasum \| cut -b 1-10)"

	VALID_COLORS=("red" "orange" "yellow" "green" "blue" "purple" "pink" "black" "white")
	COLOR="black"
	OUTPUT="output.$PREFIX.gif"
	FONT_NAME="helvetica"
	FORCE_WHITE_TEXT=0
	FORCE_TRANSPARENT_BACKGROUND=0
	SPEED=16
	DELAY=6
	HEIGHT=128
	SKIP_OUTPUT_OPEN=0
	RAINBOW_MODE=0

	while getopts ":c:o:f:s:d:H:hwtrn" opt; do
	case $opt in
	h)
	usage
	;;
	n)
	SKIP_OUTPUT_OPEN=1
	;;
	r)
	RAINBOW_MODE=1
	;;
	w)
	FORCE_WHITE_TEXT=1
	;;
	t)
	FORCE_TRANSPARENT_BACKGROUND=1
	;;
	c)
	if contains "$OPTARG" "${VALID_COLORS[@]}"; then
	COLOR="$OPTARG"
	else
	usage "Invalid color: $OPTARG"
	fi
	;;
	o)
	OUTPUT="$OPTARG"
	;;
	H)
	HEIGHT="$OPTARG"
	;;
	f)
	FONT_NAME="$OPTARG"
	;;
	d)
	DELAY="$OPTARG"
	;;
	s)
	SPEED="$OPTARG"
	;;
	\?)
	usage "Invalid option: -$OPTARG"
	;;
	:)
	usage "Option -$OPTARG requires an argument."
	exit 1
	;;
	esac
	done

	shift $((OPTIND - 1))

	# Find our font before we do anything.
	FONT_PATH="$( fc-match "${FONT_NAME}" -f'%{file}' )"
	if [ "$FONT_PATH" == "" ]; then
	usage "Could not find '${FONT_NAME}' font. Is it installed?"
	else
	echo "Using ${FONT_PATH} for ${FONT_NAME} font."
	fi

	MESSAGE="$*"
	if [ "$MESSAGE" == "" ]; then
	usage "A message is required."
	fi

	if [ "$RAINBOW_MODE" == 1 ]; then
	colors=("red" "orange" "yellow" "green" "blue" "purple" "black" "white")
	declare -a files
	for color in ${colors[@]}; do
	echo "Generate color $color ..."
	file="rainbow.step.$color.gif"
	files+=($file)
	$0 -d "$DELAY" -s "$SPEED" -H "$HEIGHT" -f "$FONT_NAME" -c "$color" -t -n -o $file "$MESSAGE"
	done
	COMBINED="rainbow.$PREFIX.gif"
	convert ${files[@]} $COMBINED
	gifsicle -b -O3 -Okeep-empty -k16 $COMBINED
	echo "Final rainbow file: $COMBINED"
	exit 0
	fi

	case $COLOR in
	red)
	FILL="#e40303"
	BACKGROUND="#4c0000"
	;;
	orange)
	FILL="#ff8c00"
	BACKGROUND="#562b00"
	;;
	yellow)
	FILL="#ffed00"
	BACKGROUND="#565100"
	;;
	green)
	FILL="#008026"
	BACKGROUND="#002705"
	;;
	blue)
	FILL="#004dff"
	BACKGROUND="#001456"
	;;
	purple)
	FILL="#750787"
	BACKGROUND="#23012a"
	;;
	pink)
	FILL="#851252"
	BACKGROUND="#e0368c"
	;;
	black)
	FILL="#111111"
	BACKGROUND="#ffffff"
	;;
	white)
	FILL="#ffffff"
	BACKGROUND="#111111"
	;;
	esac

	if [ "$FORCE_WHITE_TEXT" == 1 ]; then
	FILL="#ffffff"
	fi

	if [ "$FORCE_TRANSPARENT_BACKGROUND" == 1 ]; then
	echo "Using transparent background"
	BACKGROUND="transparent"
	fi

	# Generate image from text input
	convert \
	-background "$BACKGROUND" \
	-fill "$FILL" \
	-font "$FONT_PATH" \
	-density 200 \
	-pointsize 100 \
	"label:${MESSAGE}" \
	"/tmp/${PREFIX}_label.png"

	# Resize to 128px high
	convert \
	-resize x${HEIGHT} \
	"/tmp/${PREFIX}_label.png" \
	"/tmp/${PREFIX}_sized.png"

	# Add padding
	WIDTH="$(identify -format "%[fx:w]" "/tmp/${PREFIX}_sized.png")"
	CANVAS_SIZE=$((WIDTH + HEIGHT + HEIGHT + (HEIGHT / 4))) # HEIGHT in front, HEIGHT / 4 in back
	# convert "/tmp/${PREFIX}_sized.png" -bordercolor $BACKGROUND -border ${HEIGHT}x0 "/tmp/${PREFIX}_padded.png"
	convert \
	"/tmp/${PREFIX}_sized.png" \
	-gravity center \
	-background $BACKGROUND \
	-extent $CANVAS_SIZE \
	"/tmp/${PREFIX}_padded.png"

	# Generate individual frames

	STEP=$((HEIGHT / (64 / SPEED)))
	OFFSET=0
	I=0
	LIMIT=$((CANVAS_SIZE - HEIGHT))
	while [[ "$OFFSET" -lt "$LIMIT" ]]; do
	convert \
	"/tmp/${PREFIX}_padded.png" \
	-crop "${HEIGHT}x${HEIGHT}+${OFFSET}+0!" \
	"$(printf "/tmp/${PREFIX}_frame_%05d.png" $I)"
	I=$((I + 1))
	OFFSET=$((OFFSET + STEP))
	done

	# Compile to gif
	convert \
	-delay "$DELAY" \
	-loop 0 \
	-dispose previous \
	"/tmp/${PREFIX}_frame_*.png" \
	"$OUTPUT"

	# Clean up!
	rm /tmp/${PREFIX}_*.png

	if [ "$SKIP_OUTPUT_OPEN" == 0 ]; then
	# Optimize it
	gifsicle -b -O3 -Okeep-empty -k16 "$OUTPUT"
	echo "Your GIF is ready: $OUTPUT"
	unameOut="$(uname -s)"
	case "${unameOut}" in
	Linux*)
	xdg-open $OUTPUT
	;;
	Darwin*)
	open -a "Safari" "$OUTPUT"
	;;
	CYGWIN*)
	;;
	MINGW*)
	;;
	*)
	;;
	esac
	fi