"""

Add a ``figure-mpl`` directive that is a responsive version of ``figure``.

This implementation is very similar to ``.. figure::``, except it also allows a

``srcset=`` argument to be passed to the image tag, hence allowing responsive

resolution images.

There is no particular reason this could not be used standalone, but is meant

to be used with :doc:`/api/sphinxext_plot_directive_api`.

Note that the directory organization is a bit different than ``.. figure::``.

See the *FigureMpl* documentation below.

"""

import os

from os.path import relpath

from pathlib import PurePath, Path

import shutil

from docutils import nodes

from docutils.parsers.rst import directives

from docutils.parsers.rst.directives.images import Figure, Image

from sphinx.errors import ExtensionError

import matplotlib

class figmplnode(nodes.General, nodes.Element):

pass

class FigureMpl(Figure):

"""

Implements a directive to allow an optional hidpi image.

Meant to be used with the *plot_srcset* configuration option in conf.py,

and gets set in the TEMPLATE of plot_directive.py

e.g.::

.. figure-mpl:: plot_directive/some_plots-1.png

:alt: bar

:srcset: plot_directive/some_plots-1.png,

plot_directive/some_plots-1.2x.png 2.00x

:class: plot-directive

The resulting html (at ``some_plots.html``) is::

<img src="sphx_glr_bar_001_hidpi.png"

srcset="_images/some_plot-1.png,

_images/some_plots-1.2x.png 2.00x",

alt="bar"

class="plot_directive" />

Note that the handling of subdirectories is different than that used by the sphinx

figure directive::

.. figure-mpl:: plot_directive/nestedpage/index-1.png

:alt: bar

:srcset: plot_directive/nestedpage/index-1.png

plot_directive/nestedpage/index-1.2x.png 2.00x

:class: plot_directive

The resulting html (at ``nestedpage/index.html``)::

<img src="../_images/nestedpage-index-1.png"

srcset="../_images/nestedpage-index-1.png,

../_images/_images/nestedpage-index-1.2x.png 2.00x",

alt="bar"

class="sphx-glr-single-img" />

where the subdirectory is included in the image name for uniqueness.

"""

has_content = False

required_arguments = 1

optional_arguments = 2

final_argument_whitespace = False

option_spec = {

'alt': directives.unchanged,

'height': directives.length_or_unitless,

'width': directives.length_or_percentage_or_unitless,

'scale': directives.nonnegative_int,

'align': Image.align,

'class': directives.class_option,

'caption': directives.unchanged,

'srcset': directives.unchanged,

}

def run(self):

image_node = figmplnode()

imagenm = self.arguments[0]

image_node['alt'] = self.options.get('alt', '')

image_node['align'] = self.options.get('align', None)

image_node['class'] = self.options.get('class', None)

image_node['width'] = self.options.get('width', None)

image_node['height'] = self.options.get('height', None)

image_node['scale'] = self.options.get('scale', None)

image_node['caption'] = self.options.get('caption', None)

# we would like uri to be the highest dpi version so that

# latex etc will use that. But for now, lets just make

# imagenm... maybe pdf one day?

image_node['uri'] = imagenm

image_node['srcset'] = self.options.get('srcset', None)

return [image_node]

def _parse_srcsetNodes(st):

"""

parse srcset...

"""

entries = st.split(',')

srcset = {}

for entry in entries:

spl = entry.strip().split(' ')

if len(spl) == 1:

srcset[0] = spl[0]

elif len(spl) == 2:

mult = spl[1][:-1]

srcset[float(mult)] = spl[0]

else:

raise ExtensionError(f'srcset argument "{entry}" is invalid.')

return srcset

def _copy_images_figmpl(self, node):

# these will be the temporary place the plot-directive put the images eg:

# ../../../build/html/plot_directive/users/explain/artists/index-1.png

if node['srcset']:

srcset = _parse_srcsetNodes(node['srcset'])

else:

srcset = None

# the rst file's location: eg /Users/username/matplotlib/doc/users/explain/artists

docsource = PurePath(self.document['source']).parent

# get the relpath relative to root:

srctop = self.builder.srcdir

rel = relpath(docsource, srctop).replace('.', '').replace(os.sep, '-')

if len(rel):

rel += '-'

# eg: users/explain/artists

imagedir = PurePath(self.builder.outdir, self.builder.imagedir)

# eg: /Users/username/matplotlib/doc/build/html/_images/users/explain/artists

Path(imagedir).mkdir(parents=True, exist_ok=True)

# copy all the sources to the imagedir:

if srcset:

for src in srcset.values():

# the entries in srcset are relative to docsource's directory

abspath = PurePath(docsource, src)

name = rel + abspath.name

shutil.copyfile(abspath, imagedir / name)

else:

abspath = PurePath(docsource, node['uri'])

name = rel + abspath.name

shutil.copyfile(abspath, imagedir / name)

return imagedir, srcset, rel

def visit_figmpl_html(self, node):

imagedir, srcset, rel = _copy_images_figmpl(self, node)

# /doc/examples/subd/plot_1.rst

docsource = PurePath(self.document['source'])

# /doc/

# make sure to add the trailing slash:

srctop = PurePath(self.builder.srcdir, '')

# examples/subd/plot_1.rst

relsource = relpath(docsource, srctop)

# /doc/build/html

desttop = PurePath(self.builder.outdir, '')

# /doc/build/html/examples/subd

dest = desttop / relsource

# ../../_images/ for dirhtml and ../_images/ for html

imagerel = PurePath(relpath(imagedir, dest.parent)).as_posix()

if self.builder.name == "dirhtml":

imagerel = f'..{imagerel}'

# make uri also be relative...

nm = PurePath(node['uri'][1:]).name

uri = f'{imagerel}/{rel}{nm}'

img_attrs = {'src': uri, 'alt': node['alt']}

# make srcset str. Need to change all the prefixes!

maxsrc = uri

if srcset:

maxmult = -1

srcsetst = ''

for mult, src in srcset.items():

nm = PurePath(src[1:]).name

# ../../_images/plot_1_2_0x.png

path = f'{imagerel}/{rel}{nm}'

srcsetst += path

if mult == 0:

srcsetst += ', '

else:

srcsetst += f' {mult:1.2f}x, '

if mult > maxmult:

maxmult = mult

maxsrc = path

# trim trailing comma and space...

img_attrs['srcset'] = srcsetst[:-2]

if node['class'] is not None:

img_attrs['class'] = ' '.join(node['class'])

for style in ['width', 'height', 'scale']:

if node[style]:

if 'style' not in img_attrs:

img_attrs['style'] = f'{style}: {node[style]};'

else:

img_attrs['style'] += f'{style}: {node[style]};'

# <figure class="align-default" id="id1">

# <a class="reference internal image-reference" href="_images/index-1.2x.png">

# <img alt="_images/index-1.2x.png"

# src="_images/index-1.2x.png" style="width: 53%;" />

# </a>

# <figcaption>

# <p><span class="caption-text">Figure caption is here....</span>

# <a class="headerlink" href="#id1" title="Permalink to this image">#</a></p>

# </figcaption>

# </figure>

self.body.append(

self.starttag(

node, 'figure',

CLASS=f'align-{node["align"]}' if node['align'] else 'align-center'))

self.body.append(

self.starttag(node, 'a', CLASS='reference internal image-reference',

href=maxsrc) +

self.emptytag(node, 'img', **img_attrs) +

'</a>\n')

if node['caption']:

self.body.append(self.starttag(node, 'figcaption'))

self.body.append(self.starttag(node, 'p'))

self.body.append(self.starttag(node, 'span', CLASS='caption-text'))

self.body.append(node['caption'])

self.body.append('</span></p></figcaption>\n')

self.body.append('</figure>\n')

def visit_figmpl_latex(self, node):

if node['srcset'] is not None:

imagedir, srcset = _copy_images_figmpl(self, node)

maxmult = -1

# choose the highest res version for latex:

maxmult = max(srcset, default=-1)

node['uri'] = PurePath(srcset[maxmult]).name

self.visit_figure(node)

def depart_figmpl_html(self, node):

pass

def depart_figmpl_latex(self, node):

self.depart_figure(node)

def figurempl_addnode(app):

app.add_node(figmplnode,

html=(visit_figmpl_html, depart_figmpl_html),

latex=(visit_figmpl_latex, depart_figmpl_latex))

def setup(app):

app.add_directive("figure-mpl", FigureMpl)

figurempl_addnode(app)

metadata = {'parallel_read_safe': True, 'parallel_write_safe': True,

'version': matplotlib.__version__}

return metadata