Pillow/docs/reference/ImageDraw.rst

.. py:module:: PIL.ImageDraw
.. py:currentmodule:: PIL.ImageDraw

:py:mod:`~PIL.ImageDraw` Module
===============================

The :py:mod:`~PIL.ImageDraw` module provides simple 2D graphics for
:py:class:`~PIL.Image.Image` objects.  You can use this module to create new
images, annotate or retouch existing images, and to generate graphics on the
fly for web use.

For a more advanced drawing library for PIL, see the `aggdraw module`_.

.. _aggdraw module: https://github.com/pytroll/aggdraw

Example: Draw a gray cross over an image
----------------------------------------

::

    import sys
    from PIL import Image, ImageDraw

    with Image.open("hopper.jpg") as im:

        draw = ImageDraw.Draw(im)
        draw.line((0, 0) + im.size, fill=128)
        draw.line((0, im.size[1], im.size[0], 0), fill=128)

        # write to stdout
        im.save(sys.stdout, "PNG")


Concepts
--------

Coordinates
^^^^^^^^^^^

The graphics interface uses the same coordinate system as PIL itself, with (0,
0) in the upper left corner. Any pixels drawn outside of the image bounds will
be discarded.

Colors
^^^^^^

To specify colors, you can use numbers or tuples just as you would use with
:py:meth:`PIL.Image.new` or :py:meth:`PIL.Image.Image.putpixel`. For “1”,
“L”, and “I” images, use integers. For “RGB” images, use a 3-tuple containing
integer values. For “F” images, use integer or floating point values.

For palette images (mode “P”), use integers as color indexes. In 1.1.4 and
later, you can also use RGB 3-tuples or color names (see below). The drawing
layer will automatically assign color indexes, as long as you don’t draw with
more than 256 colors.

Color Names
^^^^^^^^^^^

See :ref:`color-names` for the color names supported by Pillow.

Fonts
^^^^^

PIL can use bitmap fonts or OpenType/TrueType fonts.

Bitmap fonts are stored in PIL's own format, where each font typically consists
of two files, one named .pil and the other usually named .pbm. The former
contains font metrics, the latter raster data.

To load a bitmap font, use the load functions in the :py:mod:`~PIL.ImageFont`
module.

To load a OpenType/TrueType font, use the truetype function in the
:py:mod:`~PIL.ImageFont` module. Note that this function depends on third-party
libraries, and may not available in all PIL builds.

Example: Draw Partial Opacity Text
----------------------------------

::

    from PIL import Image, ImageDraw, ImageFont

    # get an image
    with Image.open("Pillow/Tests/images/hopper.png").convert("RGBA") as base:

        # make a blank image for the text, initialized to transparent text color
        txt = Image.new("RGBA", base.size, (255, 255, 255, 0))

        # get a font
        fnt = ImageFont.truetype("Pillow/Tests/fonts/FreeMono.ttf", 40)
        # get a drawing context
        d = ImageDraw.Draw(txt)

        # draw text, half opacity
        d.text((10, 10), "Hello", font=fnt, fill=(255, 255, 255, 128))
        # draw text, full opacity
        d.text((10, 60), "World", font=fnt, fill=(255, 255, 255, 255))

        out = Image.alpha_composite(base, txt)

        out.show()

Example: Draw Multiline Text
----------------------------

::

    from PIL import Image, ImageDraw, ImageFont

    # create an image
    out = Image.new("RGB", (150, 100), (255, 255, 255))

    # get a font
    fnt = ImageFont.truetype("Pillow/Tests/fonts/FreeMono.ttf", 40)
    # get a drawing context
    d = ImageDraw.Draw(out)

    # draw multiline text
    d.multiline_text((10, 10), "Hello\nWorld", font=fnt, fill=(0, 0, 0))

    out.show()


Functions
---------

.. py:method:: Draw(im, mode=None)

    Creates an object that can be used to draw in the given image.

    Note that the image will be modified in place.

    :param im: The image to draw in.
    :param mode: Optional mode to use for color values.  For RGB
        images, this argument can be RGB or RGBA (to blend the
        drawing into the image).  For all other modes, this argument
        must be the same as the image mode.  If omitted, the mode
        defaults to the mode of the image.

Attributes
----------

.. py:attribute:: ImageDraw.fill
    :type: bool
    :value: False

    Selects whether :py:attr:`ImageDraw.ink` should be used as a fill or outline color.

.. py:attribute:: ImageDraw.font

    The current default font.

    Can be set per instance::

        from PIL import ImageDraw, ImageFont
        draw = ImageDraw.Draw(image)
        draw.font = ImageFont.truetype("Tests/fonts/FreeMono.ttf")

    Or globally for all future ImageDraw instances::

        from PIL import ImageDraw, ImageFont
        ImageDraw.ImageDraw.font = ImageFont.truetype("Tests/fonts/FreeMono.ttf")

.. py:attribute:: ImageDraw.fontmode

    The current font drawing mode.

    Set to ``"1"`` to disable antialiasing or ``"L"`` to enable it.

.. py:attribute:: ImageDraw.ink
    :type: int

    The internal representation of the current default color.

Methods
-------

.. py:method:: ImageDraw.getfont()

    Get the current default font, :py:attr:`ImageDraw.font`.

    If the current default font is ``None``,
    it is initialized with :py:func:`.ImageFont.load_default`.

    :returns: An image font.

.. py:method:: ImageDraw.arc(xy, start, end, fill=None, width=0)

    Draws an arc (a portion of a circle outline) between the start and end
    angles, inside the given bounding box.

    :param xy: Two points to define the bounding box. Sequence of ``[(x0, y0),
        (x1, y1)]`` or ``[x0, y0, x1, y1]``, where ``x1 >= x0`` and ``y1 >=
        y0``.
    :param start: Starting angle, in degrees. Angles are measured from 3
        o'clock, increasing clockwise.
    :param end: Ending angle, in degrees.
    :param fill: Color to use for the arc.
    :param width: The line width, in pixels.

        .. versionadded:: 5.3.0

.. py:method:: ImageDraw.bitmap(xy, bitmap, fill=None)

    Draws a bitmap (mask) at the given position, using the current fill color
    for the non-zero portions. The bitmap should be a valid transparency mask
    (mode “1”) or matte (mode “L” or “RGBA”).

    This is equivalent to doing ``image.paste(xy, color, bitmap)``.

    To paste pixel data into an image, use the
    :py:meth:`~PIL.Image.Image.paste` method on the image itself.

.. py:method:: ImageDraw.chord(xy, start, end, fill=None, outline=None, width=1)

    Same as :py:meth:`~PIL.ImageDraw.ImageDraw.arc`, but connects the end points
    with a straight line.

    :param xy: Two points to define the bounding box. Sequence of ``[(x0, y0),
        (x1, y1)]`` or ``[x0, y0, x1, y1]``, where ``x1 >= x0`` and ``y1 >=
        y0``.
    :param outline: Color to use for the outline.
    :param fill: Color to use for the fill.
    :param width: The line width, in pixels.

        .. versionadded:: 5.3.0

.. py:method:: ImageDraw.ellipse(xy, fill=None, outline=None, width=1)

    Draws an ellipse inside the given bounding box.

    :param xy: Two points to define the bounding box. Sequence of either
        ``[(x0, y0), (x1, y1)]`` or ``[x0, y0, x1, y1]``, where ``x1 >= x0``
        and ``y1 >= y0``.
    :param outline: Color to use for the outline.
    :param fill: Color to use for the fill.
    :param width: The line width, in pixels.

        .. versionadded:: 5.3.0

.. py:method:: ImageDraw.line(xy, fill=None, width=0, joint=None)

    Draws a line between the coordinates in the ``xy`` list.
    The coordinate pixels are included in the drawn line.

    :param xy: Sequence of either 2-tuples like ``[(x, y), (x, y), ...]`` or
               numeric values like ``[x, y, x, y, ...]``.
    :param fill: Color to use for the line.
    :param width: The line width, in pixels.

        .. versionadded:: 1.1.5

        .. note:: This option was broken until version 1.1.6.
    :param joint: Joint type between a sequence of lines. It can be ``"curve"``, for rounded edges, or :data:`None`.

        .. versionadded:: 5.3.0

.. py:method:: ImageDraw.pieslice(xy, start, end, fill=None, outline=None, width=1)

    Same as arc, but also draws straight lines between the end points and the
    center of the bounding box.

    :param xy: Two points to define the bounding box. Sequence of ``[(x0, y0),
        (x1, y1)]`` or ``[x0, y0, x1, y1]``, where ``x1 >= x0`` and ``y1 >=
        y0``.
    :param start: Starting angle, in degrees. Angles are measured from 3
        o'clock, increasing clockwise.
    :param end: Ending angle, in degrees.
    :param fill: Color to use for the fill.
    :param outline: Color to use for the outline.
    :param width: The line width, in pixels.

        .. versionadded:: 5.3.0

.. py:method:: ImageDraw.point(xy, fill=None)

    Draws points (individual pixels) at the given coordinates.

    :param xy: Sequence of either 2-tuples like ``[(x, y), (x, y), ...]`` or
               numeric values like ``[x, y, x, y, ...]``.
    :param fill: Color to use for the point.

.. py:method:: ImageDraw.polygon(xy, fill=None, outline=None, width=1)

    Draws a polygon.

    The polygon outline consists of straight lines between the given
    coordinates, plus a straight line between the last and the first
    coordinate. The coordinate pixels are included in the drawn polygon.

    :param xy: Sequence of either 2-tuples like ``[(x, y), (x, y), ...]`` or
               numeric values like ``[x, y, x, y, ...]``.
    :param fill: Color to use for the fill.
    :param outline: Color to use for the outline.
    :param width: The line width, in pixels.


.. py:method:: ImageDraw.regular_polygon(bounding_circle, n_sides, rotation=0, fill=None, outline=None, width=1)

    Draws a regular polygon inscribed in ``bounding_circle``,
    with ``n_sides``, and rotation of ``rotation`` degrees.

    :param bounding_circle: The bounding circle is a tuple defined
        by a point and radius.
        (e.g. ``bounding_circle=(x, y, r)`` or ``((x, y), r)``).
        The polygon is inscribed in this circle.
    :param n_sides: Number of sides
        (e.g. ``n_sides=3`` for a triangle, ``6`` for a hexagon).
    :param rotation: Apply an arbitrary rotation to the polygon
        (e.g. ``rotation=90``, applies a 90 degree rotation).
    :param fill: Color to use for the fill.
    :param outline: Color to use for the outline.
    :param width: The line width, in pixels.


.. py:method:: ImageDraw.rectangle(xy, fill=None, outline=None, width=1)

    Draws a rectangle.

    :param xy: Two points to define the bounding box. Sequence of either
            ``[(x0, y0), (x1, y1)]`` or ``[x0, y0, x1, y1]``, where ``x1 >= x0`` and
            ``y1 >= y0``. The bounding box is inclusive of both endpoints.
    :param fill: Color to use for the fill.
    :param outline: Color to use for the outline.
    :param width: The line width, in pixels.

        .. versionadded:: 5.3.0

.. py:method:: ImageDraw.rounded_rectangle(xy, radius=0, fill=None, outline=None, width=1, corners=None)

    Draws a rounded rectangle.

    :param xy: Two points to define the bounding box. Sequence of either
            ``[(x0, y0), (x1, y1)]`` or ``[x0, y0, x1, y1]``, where ``x1 >= x0`` and
            ``y1 >= y0``. The bounding box is inclusive of both endpoints.
    :param radius: Radius of the corners.
    :param fill: Color to use for the fill.
    :param outline: Color to use for the outline.
    :param width: The line width, in pixels.
    :param corners: A tuple of whether to round each corner,
                    ``(top_left, top_right, bottom_right, bottom_left)``.
                    Keyword-only argument.

    .. versionadded:: 8.2.0

.. py:method:: ImageDraw.shape(shape, fill=None, outline=None)

    .. warning:: This method is experimental.

    Draw a shape.

.. py:method:: ImageDraw.text(xy, text, fill=None, font=None, anchor=None, spacing=4, align="left", direction=None, features=None, language=None, stroke_width=0, stroke_fill=None, embedded_color=False)

    Draws the string at the given position.

    :param xy: The anchor coordinates of the text.
    :param text: String to be drawn. If it contains any newline characters,
                 the text is passed on to
                 :py:meth:`~PIL.ImageDraw.ImageDraw.multiline_text`.
    :param fill: Color to use for the text.
    :param font: An :py:class:`~PIL.ImageFont.ImageFont` instance.
    :param anchor: The text anchor alignment. Determines the relative location of
                   the anchor to the text. The default alignment is top left.
                   See :ref:`text-anchors` for valid values. This parameter is
                   ignored for non-TrueType fonts.

                    .. note:: This parameter was present in earlier versions
                              of Pillow, but implemented only in version 8.0.0.

    :param spacing: If the text is passed on to
                    :py:meth:`~PIL.ImageDraw.ImageDraw.multiline_text`,
                    the number of pixels between lines.
    :param align: If the text is passed on to
                  :py:meth:`~PIL.ImageDraw.ImageDraw.multiline_text`,
                  ``"left"``, ``"center"`` or ``"right"``. Determines the relative alignment of lines.
                  Use the ``anchor`` parameter to specify the alignment to ``xy``.
    :param direction: Direction of the text. It can be ``"rtl"`` (right to
                      left), ``"ltr"`` (left to right) or ``"ttb"`` (top to bottom).
                      Requires libraqm.

                      .. versionadded:: 4.2.0

    :param features: A list of OpenType font features to be used during text
                     layout. This is usually used to turn on optional
                     font features that are not enabled by default,
                     for example ``"dlig"`` or ``"ss01"``, but can be also
                     used to turn off default font features, for
                     example ``"-liga"`` to disable ligatures or ``"-kern"``
                     to disable kerning.  To get all supported
                     features, see `OpenType docs`_.
                     Requires libraqm.

                     .. versionadded:: 4.2.0

    :param language: Language of the text. Different languages may use
                     different glyph shapes or ligatures. This parameter tells
                     the font which language the text is in, and to apply the
                     correct substitutions as appropriate, if available.
                     It should be a `BCP 47 language code`_.
                     Requires libraqm.

                     .. versionadded:: 6.0.0

    :param stroke_width: The width of the text stroke.

                     .. versionadded:: 6.2.0

    :param stroke_fill: Color to use for the text stroke. If not given, will default to
        the ``fill`` parameter.

        .. versionadded:: 6.2.0

    :param embedded_color: Whether to use font embedded color glyphs (COLR, CBDT, SBIX).

                    .. versionadded:: 8.0.0


.. py:method:: ImageDraw.multiline_text(xy, text, fill=None, font=None, anchor=None, spacing=4, align="left", direction=None, features=None, language=None, stroke_width=0, stroke_fill=None, embedded_color=False)

    Draws the string at the given position.

    :param xy: The anchor coordinates of the text.
    :param text: String to be drawn.
    :param fill: Color to use for the text.
    :param font: An :py:class:`~PIL.ImageFont.ImageFont` instance.

    :param anchor: The text anchor alignment. Determines the relative location of
                   the anchor to the text. The default alignment is top left.
                   See :ref:`text-anchors` for valid values. This parameter is
                   ignored for non-TrueType fonts.

                    .. note:: This parameter was present in earlier versions
                              of Pillow, but implemented only in version 8.0.0.

    :param spacing: The number of pixels between lines.
    :param align: ``"left"``, ``"center"`` or ``"right"``. Determines the relative alignment of lines.
                  Use the ``anchor`` parameter to specify the alignment to ``xy``.
    :param direction: Direction of the text. It can be ``"rtl"`` (right to
                      left), ``"ltr"`` (left to right) or ``"ttb"`` (top to bottom).
                      Requires libraqm.

                      .. versionadded:: 4.2.0

    :param features: A list of OpenType font features to be used during text
                     layout. This is usually used to turn on optional
                     font features that are not enabled by default,
                     for example ``"dlig"`` or ``"ss01"``, but can be also
                     used to turn off default font features, for
                     example ``"-liga"`` to disable ligatures or ``"-kern"``
                     to disable kerning.  To get all supported
                     features, see `OpenType docs`_.
                     Requires libraqm.

                     .. versionadded:: 4.2.0

    :param language: Language of the text. Different languages may use
                     different glyph shapes or ligatures. This parameter tells
                     the font which language the text is in, and to apply the
                     correct substitutions as appropriate, if available.
                     It should be a `BCP 47 language code`_.
                     Requires libraqm.

                     .. versionadded:: 6.0.0

    :param stroke_width: The width of the text stroke.

                     .. versionadded:: 6.2.0

    :param stroke_fill: Color to use for the text stroke. If not given, will default to
                        the ``fill`` parameter.

                     .. versionadded:: 6.2.0

    :param embedded_color: Whether to use font embedded color glyphs (COLR, CBDT, SBIX).

                     .. versionadded:: 8.0.0

.. py:method:: ImageDraw.textlength(text, font=None, direction=None, features=None, language=None, embedded_color=False)

    Returns length (in pixels with 1/64 precision) of given text when rendered
    in font with provided direction, features, and language.

    This is the amount by which following text should be offset.
    Text bounding box may extend past the length in some fonts,
    e.g. when using italics or accents.

    The result is returned as a float; it is a whole number if using basic layout.

    Note that the sum of two lengths may not equal the length of a concatenated
    string due to kerning. If you need to adjust for kerning, include the following
    character and subtract its length.

    For example, instead of ::

        hello = draw.textlength("Hello", font)
        world = draw.textlength("World", font)
        hello_world = hello + world  # not adjusted for kerning
        assert hello_world == draw.textlength("HelloWorld", font)  # may fail

    use ::

        hello = draw.textlength("HelloW", font) - draw.textlength(
            "W", font
        )  # adjusted for kerning
        world = draw.textlength("World", font)
        hello_world = hello + world  # adjusted for kerning
        assert hello_world == draw.textlength("HelloWorld", font)  # True

    or disable kerning with (requires libraqm) ::

        hello = draw.textlength("Hello", font, features=["-kern"])
        world = draw.textlength("World", font, features=["-kern"])
        hello_world = hello + world  # kerning is disabled, no need to adjust
        assert hello_world == draw.textlength("HelloWorld", font, features=["-kern"])  # True

    .. versionadded:: 8.0.0

    :param text: Text to be measured. May not contain any newline characters.
    :param font: An :py:class:`~PIL.ImageFont.ImageFont` instance.
    :param direction: Direction of the text. It can be ``"rtl"`` (right to
                      left), ``"ltr"`` (left to right) or ``"ttb"`` (top to bottom).
                      Requires libraqm.
    :param features: A list of OpenType font features to be used during text
                     layout. This is usually used to turn on optional
                     font features that are not enabled by default,
                     for example ``"dlig"`` or ``"ss01"``, but can be also
                     used to turn off default font features, for
                     example ``"-liga"`` to disable ligatures or ``"-kern"``
                     to disable kerning.  To get all supported
                     features, see `OpenType docs`_.
                     Requires libraqm.
    :param language: Language of the text. Different languages may use
                     different glyph shapes or ligatures. This parameter tells
                     the font which language the text is in, and to apply the
                     correct substitutions as appropriate, if available.
                     It should be a `BCP 47 language code`_.
                     Requires libraqm.
    :param embedded_color: Whether to use font embedded color glyphs (COLR, CBDT, SBIX).
    :return: Width for horizontal, height for vertical text.

.. py:method:: ImageDraw.textbbox(xy, text, font=None, anchor=None, spacing=4, align="left", direction=None, features=None, language=None, stroke_width=0, embedded_color=False)

    Returns bounding box (in pixels) of given text relative to given anchor
    when rendered in font with provided direction, features, and language.
    Only supported for TrueType fonts.

    Use :py:meth:`textlength` to get the offset of following text with
    1/64 pixel precision. The bounding box includes extra margins for
    some fonts, e.g. italics or accents.

    .. versionadded:: 8.0.0

    :param xy: The anchor coordinates of the text.
    :param text: Text to be measured. If it contains any newline characters,
                 the text is passed on to
                 :py:meth:`~PIL.ImageDraw.ImageDraw.multiline_textbbox`.
    :param font: A :py:class:`~PIL.ImageFont.FreeTypeFont` instance.
    :param anchor: The text anchor alignment. Determines the relative location of
                   the anchor to the text. The default alignment is top left.
                   See :ref:`text-anchors` for valid values. This parameter is
                   ignored for non-TrueType fonts.
    :param spacing: If the text is passed on to
                    :py:meth:`~PIL.ImageDraw.ImageDraw.multiline_textbbox`,
                    the number of pixels between lines.
    :param align: If the text is passed on to
                  :py:meth:`~PIL.ImageDraw.ImageDraw.multiline_textbbox`,
                  ``"left"``, ``"center"`` or ``"right"``. Determines the relative alignment of lines.
                  Use the ``anchor`` parameter to specify the alignment to ``xy``.
    :param direction: Direction of the text. It can be ``"rtl"`` (right to
                      left), ``"ltr"`` (left to right) or ``"ttb"`` (top to bottom).
                      Requires libraqm.
    :param features: A list of OpenType font features to be used during text
                     layout. This is usually used to turn on optional
                     font features that are not enabled by default,
                     for example ``"dlig"`` or ``"ss01"``, but can be also
                     used to turn off default font features, for
                     example ``"-liga"`` to disable ligatures or ``"-kern"``
                     to disable kerning.  To get all supported
                     features, see `OpenType docs`_.
                     Requires libraqm.
    :param language: Language of the text. Different languages may use
                     different glyph shapes or ligatures. This parameter tells
                     the font which language the text is in, and to apply the
                     correct substitutions as appropriate, if available.
                     It should be a `BCP 47 language code`_.
                     Requires libraqm.
    :param stroke_width: The width of the text stroke.
    :param embedded_color: Whether to use font embedded color glyphs (COLR, CBDT, SBIX).
    :return: ``(left, top, right, bottom)`` bounding box

.. py:method:: ImageDraw.multiline_textbbox(xy, text, font=None, anchor=None, spacing=4, align="left", direction=None, features=None, language=None, stroke_width=0, embedded_color=False)

    Returns bounding box (in pixels) of given text relative to given anchor
    when rendered in font with provided direction, features, and language.
    Only supported for TrueType fonts.

    Use :py:meth:`textlength` to get the offset of following text with
    1/64 pixel precision. The bounding box includes extra margins for
    some fonts, e.g. italics or accents.

    .. versionadded:: 8.0.0

    :param xy: The anchor coordinates of the text.
    :param text: Text to be measured.
    :param font: A :py:class:`~PIL.ImageFont.FreeTypeFont` instance.
    :param anchor: The text anchor alignment. Determines the relative location of
                   the anchor to the text. The default alignment is top left.
                   See :ref:`text-anchors` for valid values. This parameter is
                   ignored for non-TrueType fonts.
    :param spacing: The number of pixels between lines.
    :param align: ``"left"``, ``"center"`` or ``"right"``. Determines the relative alignment of lines.
                  Use the ``anchor`` parameter to specify the alignment to ``xy``.
    :param direction: Direction of the text. It can be ``"rtl"`` (right to
                      left), ``"ltr"`` (left to right) or ``"ttb"`` (top to bottom).
                      Requires libraqm.
    :param features: A list of OpenType font features to be used during text
                     layout. This is usually used to turn on optional
                     font features that are not enabled by default,
                     for example ``"dlig"`` or ``"ss01"``, but can be also
                     used to turn off default font features, for
                     example ``"-liga"`` to disable ligatures or ``"-kern"``
                     to disable kerning.  To get all supported
                     features, see `OpenType docs`_.
                     Requires libraqm.
    :param language: Language of the text. Different languages may use
                     different glyph shapes or ligatures. This parameter tells
                     the font which language the text is in, and to apply the
                     correct substitutions as appropriate, if available.
                     It should be a `BCP 47 language code`_.
                     Requires libraqm.
    :param stroke_width: The width of the text stroke.
    :param embedded_color: Whether to use font embedded color glyphs (COLR, CBDT, SBIX).
    :return: ``(left, top, right, bottom)`` bounding box

.. py:method:: getdraw(im=None, hints=None)

    .. warning:: This method is experimental.

    A more advanced 2D drawing interface for PIL images,
    based on the WCK interface.

    :param im: The image to draw in.
    :param hints: An optional list of hints.
    :returns: A (drawing context, drawing resource factory) tuple.

.. py:method:: floodfill(image, xy, value, border=None, thresh=0)

    .. warning:: This method is experimental.

    Fills a bounded region with a given color.

    :param image: Target image.
    :param xy: Seed position (a 2-item coordinate tuple).
    :param value: Fill color.
    :param border: Optional border value.  If given, the region consists of
        pixels with a color different from the border color.  If not given,
        the region consists of pixels having the same color as the seed
        pixel.
    :param thresh: Optional threshold value which specifies a maximum
        tolerable difference of a pixel value from the 'background' in
        order for it to be replaced. Useful for filling regions of non-
        homogeneous, but similar, colors.

.. _BCP 47 language code: https://www.w3.org/International/articles/language-tags/
.. _OpenType docs: https://learn.microsoft.com/en-us/typography/opentype/spec/featurelist