Commit 8ccd0569 authored by Akira Yokosawa's avatar Akira Yokosawa Committed by Jonathan Corbet
Browse files

docs: sphinx/kfigure.py: Use inkscape(1) for SVG -> PDF conversion 



Using convert(1) of ImageMagick for SVG -> PDF conversion results in
PDFs containing raster (bitmap) images which sometimes look blurry.

Ideally speaking, SVG to PDF conversion should retain vector graphics
in SVG.

rsvg-convert(1) can do such conversions with regard to SVG files
generated by dot(1).

Unfortunately, rsvg-convert(1) does not cover some of SVG features
specific to Inkscape.
inkscape(1) of Inkscape naturally covers such SVG features.

So add a route in svg2pdf() so that inkscape(1) is used when it is
available.

Note:
    After this change, if you have Inkscape installed, ImageMagick nor
    librsvg are not required.

Signed-off-by: default avatarAkira Yokosawa <akiyks@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/3eea2a8d-c52d-ee07-cf7b-83784c6f6e4b@gmail.com


Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent ecf5fb58

Documentation/sphinx/kfigure.py

+48 −20
Original line number Diff line number Diff line
@@ -37,6 +37,7 @@ u""" 
    * SVG to PDF: To generate PDF, you need at least one of this tools:



      - ``convert(1)``: ImageMagick (https://www.imagemagick.org)

      - ``inkscape(1)``: Inkscape (https://inkscape.org/)



    List of customizations:
@@ -121,6 +122,11 @@ convert_cmd = None 
# librsvg's rsvg-convert(1) support

rsvg_convert_cmd = None



# Inkscape's inkscape(1) support

inkscape_cmd = None

# Inkscape prior to 1.0 uses different command options

inkscape_ver_one = False





def setup(app):

    # check toolchain first
@@ -169,11 +175,13 @@ def setupTools(app): 
    This function is called once, when the builder is initiated.

    """

    global dot_cmd, dot_Tpdf, convert_cmd, rsvg_convert_cmd   # pylint: disable=W0603

    global inkscape_cmd, inkscape_ver_one  # pylint: disable=W0603

    kernellog.verbose(app, "kfigure: check installed tools ...")



    dot_cmd = which('dot')

    convert_cmd = which('convert')

    rsvg_convert_cmd = which('rsvg-convert')

    inkscape_cmd = which('inkscape')



    if dot_cmd:

        kernellog.verbose(app, "use dot(1) from: " + dot_cmd)
@@ -190,12 +198,25 @@ def setupTools(app): 
    else:

        kernellog.warn(app, "dot(1) not found, for better output quality install "

                       "graphviz from https://www.graphviz.org")

    if inkscape_cmd:

        kernellog.verbose(app, "use inkscape(1) from: " + inkscape_cmd)

        inkscape_ver = subprocess.check_output([inkscape_cmd, '--version'])

        ver_one_ptn = b'Inkscape 1'

        inkscape_ver_one = re.search(ver_one_ptn, inkscape_ver)

        convert_cmd = None

        rsvg_convert_cmd = None

        dot_Tpdf = False



    else:

        if convert_cmd:

            kernellog.verbose(app, "use convert(1) from: " + convert_cmd)

        else:

            kernellog.warn(app,

            "convert(1) not found, for SVG to PDF conversion install "

                "Neither inkscape(1) nor convert(1) found.\n"

                "For SVG to PDF conversion, "

                "install either Inkscape (https://inkscape.org/) (preferred) or\n"

                "ImageMagick (https://www.imagemagick.org)")



        if rsvg_convert_cmd:

            kernellog.verbose(app, "use rsvg-convert(1) from: " + rsvg_convert_cmd)

            kernellog.verbose(app, "use 'dot -Tsvg' and rsvg-convert(1) for DOT -> PDF conversion")
@@ -203,8 +224,7 @@ def setupTools(app): 
        else:

            kernellog.verbose(app,

                "rsvg-convert(1) not found.\n"

            "  SVG -> PDF conversion by convert() can be poor quality.\n"

            "  Install librsvg (https://gitlab.gnome.org/GNOME/librsvg)")

                "  SVG rendering of convert(1) is done by ImageMagick-native renderer.")

            if dot_Tpdf:

                kernellog.verbose(app, "use 'dot -Tpdf' for DOT -> PDF conversion")

            else:
@@ -274,7 +294,7 @@ def convert_image(img_node, translator, src_fname=None): 
    elif in_ext == '.svg':



        if translator.builder.format == 'latex':

            if convert_cmd is None:

            if not inkscape_cmd and convert_cmd is None:

                kernellog.verbose(app,

                                  "no SVG to PDF conversion available / include SVG raw.")

                img_node.replace_self(file2literal(src_fname))
@@ -342,16 +362,24 @@ def dot2format(app, dot_fname, out_fname): 
    return bool(exit_code == 0)



def svg2pdf(app, svg_fname, pdf_fname):

    """Converts SVG to PDF with ``convert(1)`` command.

    """Converts SVG to PDF with ``inkscape(1)`` or ``convert(1)`` command.



    Uses ``convert(1)`` from ImageMagick (https://www.imagemagick.org) for

    conversion.  Returns ``True`` on success and ``False`` if an error occurred.

    Uses ``inkscape(1)`` from Inkscape (https://inkscape.org/) or ``convert(1)``

    from ImageMagick (https://www.imagemagick.org) for conversion.

    Returns ``True`` on success and ``False`` if an error occurred.



    * ``svg_fname`` pathname of the input SVG file with extension (``.svg``)

    * ``pdf_name``  pathname of the output PDF file with extension (``.pdf``)



    """

    cmd = [convert_cmd, svg_fname, pdf_fname]



    if inkscape_cmd:

        if inkscape_ver_one:

            cmd = [inkscape_cmd, '-o', pdf_fname, svg_fname]

        else:

            cmd = [inkscape_cmd, '-z', '--export-pdf=%s' % pdf_fname, svg_fname]



    # use stdout and stderr from parent

    exit_code = subprocess.call(cmd)

    if exit_code != 0: