Jul 20, 2022 · Jul 21, 2022 · Jul 21, 2022 · Jul 21, 2022 · Jul 21, 2022
diff --git a/doc/users/next_whats_new/url_in_images_for_pdfs.rst b/doc/users/next_whats_new/url_in_images_for_pdfs.rst
 URL Support for Images in PDF Backend
 -------------------------------------

 The PDF backend can now generate clickable images if a URL is provided to the
 image. There are a few limitations worth noting though:

 * If parts of the image are clipped, the non-visible parts are still clickable.
 * If there are transforms applied to the image, the whole enclosing rectangle
  is clickable. However, if you use ``interpolation='none'`` for the image,
  only the transformed image area is clickable (depending on viewer support).
diff --git a/lib/matplotlib/backends/backend_pdf.py b/lib/matplotlib/backends/backend_pdf.py
    return r


 def_calculate_quad_point_coordinates(x, y, width, height, angle=0):
 def_calculate_rotated_quad_point_coordinates(x, y, width, height, angle):
    """
    Calculate the coordinates of rectangle when rotated by angle around x, y
    """

    angle = math.radians(-angle)
    angle = math.radians(angle)
    sin_angle = math.sin(angle)
    cos_angle = math.cos(angle)
    a = x + height * sin_angle
    width_cos = width * cos_angle
    width_sin = width * sin_angle
    a = x - height * sin_angle
    b = y + height * cos_angle
    c =x +width * cos_angle + height * sin_angle
    d =y - width * sin_angle + height * cos_angle
    e = x +width * cos_angle
    f = y- width * sin_angle
    c =a +width_cos
    d =b + width_sin
    e = x +width_cos
    f = y+ width_sin
    return ((x, y), (e, f), (c, d), (a, b))


 def_get_coordinates_of_block(x, y,width, height, angle=0):
 def_calculate_transformed_quad_point_coordinates(x, y,trans):
    """
    Get the coordinates of rotated rectangle and rectangle that covers the
    rotated rectangle.
    Calculate the coordinates of rectangle when transformed by trans
    positioned at x, y
    """
    tr1, tr2, tr3, tr4, tr5, tr6 = trans
    # Conceptual code
    # width = 1
    # height = 1
    # a = x + 0 * tr1 + height * tr3 + tr5
    # b = y + 0 * tr2 + height * tr4 + tr6
    # c = x + width * tr1 + height * tr3 + tr5
    # d = y + width * tr2 + height * tr4 + tr6
    # e = x + width * tr1 + 0 * tr3 + tr5
    # f = y + width * tr2 + 0 * tr4 + tr6
    # x = x + 0 * tr1 + 0 * tr3 + tr5
    # y = y + 0 * tr2 + 0 * tr4 + tr6
    x = x + tr5
    y = y + tr6
    a = x + tr3
    b = y + tr4
    c = a + tr1
    d = b + tr2
    e = x + tr1
    f = y + tr2
    return (((x, y), (e, f), (c, d), (a, b)),
            (0 if math.isclose(tr2, 0) else 45))


 def _get_coordinates_of_block(x, y, width, height, angle, trans):
    """
    Get the coordinates of rotated or transformed rectangle and rectangle
    that covers the rotated or transformed rectangle.
    """

    vertices = _calculate_quad_point_coordinates(x, y, width,
                                                 height, angle)

    if trans is None:
        vertices = _calculate_rotated_quad_point_coordinates(x, y, width,
                                                             height, angle)
    else:
        vertices, angle = _calculate_transformed_quad_point_coordinates(x, y,
                                                                        trans)
    # Find min and max values for rectangle
    # adjust so that QuadPoints is inside Rect
    # PDF docs says that QuadPoints should be ignored if any point lies
    max_x = max(v[0] for v in vertices) + pad
    max_y = max(v[1] for v in vertices) + pad
    return (tuple(itertools.chain.from_iterable(vertices)),
            (min_x, min_y, max_x, max_y))
            (min_x, min_y, max_x, max_y), angle)


 def _get_link_annotation(gc, x, y, width, height, angle=0):
 def _get_link_annotation(gc, x, y, width, height, angle=0, trans=None):
    """
    Create a link annotation object for embedding URLs.
    """
    quadpoints, rect = _get_coordinates_of_block(x, y, width, height, angle)
    link_annotation = {
        'Type': Name('Annot'),
        'Subtype': Name('Link'),
        'Rect': rect,
        'Border': [0, 0, 0],
        'A': {
            'S': Name('URI'),
            'URI': gc.get_url(),
        },
    }
    quadpoints, rect, angle = _get_coordinates_of_block(x, y, width, height,
                                                        angle, trans)
    link_annotation['Rect'] = rect
    if angle % 90:
        # Add QuadPoints
        link_annotation['QuadPoints'] = quadpoints

    return link_annotation



        self.check_gc(gc)

        w = 72.0 * w / self.image_dpi
        h = 72.0 * h / self.image_dpi

        imob = self.file.imageObject(im)

        if transform is None:
            w = 72.0 * w / self.image_dpi
            h = 72.0 * h / self.image_dpi
            if gc.get_url() is not None:
                self._add_link_annotation(gc, x, y, w, h)
            self.file.output(Op.gsave,
                             w, 0, 0, h, x, y, Op.concat_matrix,
                             imob, Op.use_xobject, Op.grestore)
        else:
            tr1, tr2, tr3, tr4, tr5, tr6 = transform.frozen().to_values()
            trans = transform.frozen().to_values()
            if gc.get_url() is not None:
                self._add_link_annotation(gc, x, y, w, h, trans=trans)

            self.file.output(Op.gsave,
                             1, 0, 0, 1, x, y, Op.concat_matrix,
 tr1, tr2, tr3, tr4, tr5, tr6, Op.concat_matrix,
 *trans, Op.concat_matrix,
                             imob, Op.use_xobject, Op.grestore)

    def draw_path(self, gc, path, transform, rgbFace=None):
            gc.get_sketch_params())
        self.file.output(self.gc.paint())

    def _add_link_annotation(self, gc, x, y, width, height, angle=0,
                             trans=None):
        self.file._annotations[-1][1].append(
            _get_link_annotation(gc, x, y, width, height, angle, trans))

    def draw_path_collection(self, gc, master_transform, paths, all_transforms,
                             offsets, offsetTrans, facecolors, edgecolors,
                             linewidths, linestyles, antialiaseds, urls,
            self._text2path.mathtext_parser.parse(s, 72, prop)

        if gc.get_url() is not None:
            self.file._annotations[-1][1].append(_get_link_annotation(
                gc, x, y, width, height, angle))
            self._add_link_annotation(gc, x, y, width, height, angle)

        fonttype = mpl.rcParams['pdf.fonttype']

            page, = dvi

        if gc.get_url() is not None:
            self.file._annotations[-1][1].append(_get_link_annotation(
                gc, x, y, page.width, page.height, angle))
            self._add_link_annotation(gc, x, y, page.width, page.height, angle)

        # Gather font information and do some setup for combining
        # characters into strings. The variable seq will contain a
        if gc.get_url() is not None:
            font.set_text(s)
            width, height = font.get_width_height()
            self.file._annotations[-1][1].append(_get_link_annotation(
                gc, x, y, width / 64, height / 64, angle))
            self._add_link_annotation(gc, x, y, width/64, height/64, angle)

        # If fonttype is neither 3 nor 42, emit the whole string at once
        # without manual kerning.
diff --git a/lib/matplotlib/tests/test_backend_pdf.py b/lib/matplotlib/tests/test_backend_pdf.py
    fig.text(0, .75, s, size=20)


 def test_image_url():
    pikepdf = pytest.importorskip('pikepdf')

    image_url = 'https://test_image_urls.matplotlib.org/'
    image_url2 = 'https://test_image_urls2.matplotlib.org/'

    X, Y = np.meshgrid(np.arange(-5, 5, 1), np.arange(-5, 5, 1))
    Z = np.sin(Y ** 2)
    fig, ax = plt.subplots()
    ax.imshow(Z, extent=[0, 1, 0, 1], url=image_url)
    with io.BytesIO() as fd:
        fig.savefig(fd, format="pdf")
        with pikepdf.Pdf.open(fd) as pdf:
            annots = pdf.pages[0].Annots

            # Iteration over Annots must occur within the context manager,
            # otherwise it may fail depending on the pdf structure.
            annot = next(
                (a for a in annots if a.A.URI == image_url),
                None)
            assert annot is not None
            # Positions in points (72 per inch.)
            assert annot.Rect == [decimal.Decimal('122.4'),
                                  decimal.Decimal('43.2'),
                                  468,
                                  decimal.Decimal('388.8')]
    ax.set_xlim(0, 3)
    ax.imshow(Z[::-1], extent=[2, 3, 0, 1], url=image_url2)
    # Must save as separate images
    plt.rcParams['image.composite_image'] = False
    with io.BytesIO() as fd:
        fig.savefig(fd, format="pdf")
        with pikepdf.Pdf.open(fd) as pdf:
            annots = pdf.pages[0].Annots

            # Iteration over Annots must occur within the context manager,
            # otherwise it may fail depending on the pdf structure.
            annot = next(
                (a for a in annots if a.A.URI == image_url2),
                None)
            assert annot is not None
            # Positions in points (72 per inch.)
            assert annot.Rect == [decimal.Decimal('369.6'),
                                  decimal.Decimal('141.6'),
                                  decimal.Decimal('518.64'),
                                  decimal.Decimal('290.64')]


 def test_transformed_image_url():
    pikepdf = pytest.importorskip('pikepdf')

    image_url = 'https://test_image_urls.matplotlib.org/'

    X, Y = np.meshgrid(np.arange(-5, 5, 1), np.arange(-5, 5, 1))
    Z = np.sin(Y ** 2)
    fig, ax = plt.subplots()
    im = ax.imshow(Z, interpolation='none', url=image_url)
    with io.BytesIO() as fd:
        fig.savefig(fd, format="pdf")
        with pikepdf.Pdf.open(fd) as pdf:
            annots = pdf.pages[0].Annots

            # Iteration over Annots must occur within the context manager,
            # otherwise it may fail depending on the pdf structure.
            annot = next(
                (a for a in annots if a.A.URI == image_url),
                None)
            assert annot is not None
            # Positions in points (72 per inch.)
            assert annot.Rect == [decimal.Decimal('122.4'),
                                  decimal.Decimal('43.2'),
                                  decimal.Decimal('468.4'),
                                  decimal.Decimal('389.2')]
            assert getattr(annot, 'QuadPoints', None) is None
    # Transform
    im.set_transform(mpl.transforms.Affine2D().skew_deg(30, 15) + ax.transData)
    with io.BytesIO() as fd:
        fig.savefig(fd, format="pdf")
        with pikepdf.Pdf.open(fd) as pdf:
            annots = pdf.pages[0].Annots

            # Iteration over Annots must occur within the context manager,
            # otherwise it may fail depending on the pdf structure.
            annot = next(
                (a for a in annots if a.A.URI == image_url),
                None)
            assert annot is not None
            # Positions in points (72 per inch.)
            assert annot.Rect[0] == decimal.Decimal('112.411830343')
            assert getattr(annot, 'QuadPoints', None) is not None
            # Positions in points (72 per inch)
            assert annot.Rect[0] == \
               annot.QuadPoints[0] - decimal.Decimal('0.00001')


 def test_glyphs_subset():
    fpath = str(_get_data_path("fonts/ttf/DejaVuSerif.ttf"))
    chars = "these should be subsetted! 1234567890"
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,10 @@
		URL Support for Images in PDF Backend
		-------------------------------------

		The PDF backend can now generate clickable images if a URL is provided to the
		image. There are a few limitations worth noting though:

		* If parts of the image are clipped, the non-visible parts are still clickable.
Copy link Member QuLogicJul 21, 2022 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Does this mean, if you zoom in on the image, parts outside the Axes will be clickable? Copy link MemberAuthor oscargusJul 21, 2022 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Yes. It is sort of easy to fix for non-transformed images (if there is a way to get the Axes extents from the gc(?). But for transformed it is much harder. (I think the same holds for texts.)
		* If there are transforms applied to the image, the whole enclosing rectangle
		is clickable. However, if you use ``interpolation='none'`` for the image,
		only the transformed image area is clickable (depending on viewer support).
Comment on lines +8 to +10 Copy link Member QuLogicJul 21, 2022 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Sorry, I'm confused about what this means. Copy link MemberAuthor oscargusJul 21, 2022 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. First sentence: Basically, the image with the hand drawn "rectangle" above is clickable. Probably there is a better wording for it. Second sentence: if you rely on the PDF transform (i.e. set interpolation='none' and possibly a few more conditions) the clickable area is the image. Bracket part: not all PDF viewers support that and will fall back on the red rectangle.
Original file line number	Diff line number	Diff line change
Expand Up		@@ -230,32 +230,66 @@ def _datetime_to_pdf(d):
		return r


		def_calculate_quad_point_coordinates(x, y, width, height, angle=0):
		def_calculate_rotated_quad_point_coordinates(x, y, width, height, angle):
		"""
		Calculate the coordinates of rectangle when rotated by angle around x, y
		"""

		angle = math.radians(-angle)
		angle = math.radians(angle)
		sin_angle = math.sin(angle)
		cos_angle = math.cos(angle)
		a = x + height * sin_angle
		width_cos = width * cos_angle
		width_sin = width * sin_angle
		a = x - height * sin_angle
		b = y + height * cos_angle
		c =x +width * cos_angle + height * sin_angle
		d =y - width * sin_angle + height * cos_angle
		e = x +width * cos_angle
		f = y- width * sin_angle
		c =a +width_cos
		d =b + width_sin
		e = x +width_cos
		f = y+ width_sin
		return ((x, y), (e, f), (c, d), (a, b))


		def_get_coordinates_of_block(x, y,width, height, angle=0):
		def_calculate_transformed_quad_point_coordinates(x, y,trans):
		"""
		Get the coordinates of rotated rectangle and rectangle that covers the
		rotated rectangle.
		Calculate the coordinates of rectangle when transformed by trans
		positioned at x, y
		"""
		tr1, tr2, tr3, tr4, tr5, tr6 = trans
		# Conceptual code
		# width = 1
		# height = 1
		# a = x + 0 * tr1 + height * tr3 + tr5
		# b = y + 0 * tr2 + height * tr4 + tr6
		# c = x + width * tr1 + height * tr3 + tr5
		# d = y + width * tr2 + height * tr4 + tr6
		# e = x + width * tr1 + 0 * tr3 + tr5
		# f = y + width * tr2 + 0 * tr4 + tr6
		# x = x + 0 * tr1 + 0 * tr3 + tr5
		# y = y + 0 * tr2 + 0 * tr4 + tr6
		x = x + tr5
		y = y + tr6
		a = x + tr3
		b = y + tr4
		c = a + tr1
		d = b + tr2
		e = x + tr1
		f = y + tr2
		return (((x, y), (e, f), (c, d), (a, b)),
		(0 if math.isclose(tr2, 0) else 45))


		def _get_coordinates_of_block(x, y, width, height, angle, trans):
		"""
		Get the coordinates of rotated or transformed rectangle and rectangle
		that covers the rotated or transformed rectangle.
		"""

		vertices = _calculate_quad_point_coordinates(x, y, width,
		height, angle)

		if trans is None:
		vertices = _calculate_rotated_quad_point_coordinates(x, y, width,
		height, angle)
		else:
		vertices, angle = _calculate_transformed_quad_point_coordinates(x, y,
		trans)
		# Find min and max values for rectangle
		# adjust so that QuadPoints is inside Rect
		# PDF docs says that QuadPoints should be ignored if any point lies
Expand All		@@ -268,27 +302,29 @@ def _get_coordinates_of_block(x, y, width, height, angle=0):
		max_x = max(v[0] for v in vertices) + pad
		max_y = max(v[1] for v in vertices) + pad
		return (tuple(itertools.chain.from_iterable(vertices)),
		(min_x, min_y, max_x, max_y))
		(min_x, min_y, max_x, max_y), angle)


		def _get_link_annotation(gc, x, y, width, height, angle=0):
		def _get_link_annotation(gc, x, y, width, height, angle=0, trans=None):
		"""
		Create a link annotation object for embedding URLs.
		"""
		quadpoints, rect = _get_coordinates_of_block(x, y, width, height, angle)
		link_annotation = {
		'Type': Name('Annot'),
		'Subtype': Name('Link'),
		'Rect': rect,
		'Border': [0, 0, 0],
		'A': {
		'S': Name('URI'),
		'URI': gc.get_url(),
		},
		}
		quadpoints, rect, angle = _get_coordinates_of_block(x, y, width, height,
		angle, trans)
		link_annotation['Rect'] = rect
		if angle % 90:
		# Add QuadPoints
		link_annotation['QuadPoints'] = quadpoints

		return link_annotation


Expand DownExpand Up		@@ -2012,21 +2048,24 @@ def draw_image(self, gc, x, y, im, transform=None):

		self.check_gc(gc)

		w = 72.0 * w / self.image_dpi
		h = 72.0 * h / self.image_dpi

		imob = self.file.imageObject(im)

		if transform is None:
		w = 72.0 * w / self.image_dpi
		h = 72.0 * h / self.image_dpi
		if gc.get_url() is not None:
		self._add_link_annotation(gc, x, y, w, h)
		self.file.output(Op.gsave,
		w, 0, 0, h, x, y, Op.concat_matrix,
		imob, Op.use_xobject, Op.grestore)
		else:
		tr1, tr2, tr3, tr4, tr5, tr6 = transform.frozen().to_values()
		trans = transform.frozen().to_values()
		if gc.get_url() is not None:
		self._add_link_annotation(gc, x, y, w, h, trans=trans)

		self.file.output(Op.gsave,
		1, 0, 0, 1, x, y, Op.concat_matrix,
		tr1, tr2, tr3, tr4, tr5, tr6, Op.concat_matrix,
		*trans, Op.concat_matrix,
		imob, Op.use_xobject, Op.grestore)

		def draw_path(self, gc, path, transform, rgbFace=None):
Expand All		@@ -2038,6 +2077,11 @@ def draw_path(self, gc, path, transform, rgbFace=None):
		gc.get_sketch_params())
		self.file.output(self.gc.paint())

		def _add_link_annotation(self, gc, x, y, width, height, angle=0,
		trans=None):
		self.file._annotations[-1][1].append(
		_get_link_annotation(gc, x, y, width, height, angle, trans))

		def draw_path_collection(self, gc, master_transform, paths, all_transforms,
		offsets, offsetTrans, facecolors, edgecolors,
		linewidths, linestyles, antialiaseds, urls,
Expand DownExpand Up		@@ -2206,8 +2250,7 @@ def draw_mathtext(self, gc, x, y, s, prop, angle):
		self._text2path.mathtext_parser.parse(s, 72, prop)

		if gc.get_url() is not None:
		self.file._annotations[-1][1].append(_get_link_annotation(
		gc, x, y, width, height, angle))
		self._add_link_annotation(gc, x, y, width, height, angle)

		fonttype = mpl.rcParams['pdf.fonttype']

Expand DownExpand Up		@@ -2263,8 +2306,7 @@ def draw_tex(self, gc, x, y, s, prop, angle, *, mtext=None):
		page, = dvi

		if gc.get_url() is not None:
		self.file._annotations[-1][1].append(_get_link_annotation(
		gc, x, y, page.width, page.height, angle))
		self._add_link_annotation(gc, x, y, page.width, page.height, angle)

		# Gather font information and do some setup for combining
		# characters into strings. The variable seq will contain a
Expand DownExpand Up		@@ -2364,8 +2406,7 @@ def draw_text(self, gc, x, y, s, prop, angle, ismath=False, mtext=None):
		if gc.get_url() is not None:
		font.set_text(s)
		width, height = font.get_width_height()
		self.file._annotations[-1][1].append(_get_link_annotation(
		gc, x, y, width / 64, height / 64, angle))
		self._add_link_annotation(gc, x, y, width/64, height/64, angle)

		# If fonttype is neither 3 nor 42, emit the whole string at once
		# without manual kerning.
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -360,6 +360,101 @@ def test_kerning():
		fig.text(0, .75, s, size=20)


		def test_image_url():
		pikepdf = pytest.importorskip('pikepdf')

		image_url = 'https://test_image_urls.matplotlib.org/'
		image_url2 = 'https://test_image_urls2.matplotlib.org/'

		X, Y = np.meshgrid(np.arange(-5, 5, 1), np.arange(-5, 5, 1))
		Z = np.sin(Y ** 2)
		fig, ax = plt.subplots()
		ax.imshow(Z, extent=[0, 1, 0, 1], url=image_url)
		with io.BytesIO() as fd:
		fig.savefig(fd, format="pdf")
		with pikepdf.Pdf.open(fd) as pdf:
		annots = pdf.pages[0].Annots

		# Iteration over Annots must occur within the context manager,
		# otherwise it may fail depending on the pdf structure.
		annot = next(
		(a for a in annots if a.A.URI == image_url),
		None)
		assert annot is not None
		# Positions in points (72 per inch.)
		assert annot.Rect == [decimal.Decimal('122.4'),
		decimal.Decimal('43.2'),
		468,
		decimal.Decimal('388.8')]
		ax.set_xlim(0, 3)
		ax.imshow(Z[::-1], extent=[2, 3, 0, 1], url=image_url2)
		# Must save as separate images
		plt.rcParams['image.composite_image'] = False
		with io.BytesIO() as fd:
		fig.savefig(fd, format="pdf")
		with pikepdf.Pdf.open(fd) as pdf:
		annots = pdf.pages[0].Annots

		# Iteration over Annots must occur within the context manager,
		# otherwise it may fail depending on the pdf structure.
		annot = next(
		(a for a in annots if a.A.URI == image_url2),
		None)
		assert annot is not None
		# Positions in points (72 per inch.)
		assert annot.Rect == [decimal.Decimal('369.6'),
		decimal.Decimal('141.6'),
		decimal.Decimal('518.64'),
		decimal.Decimal('290.64')]


		def test_transformed_image_url():
		pikepdf = pytest.importorskip('pikepdf')

		image_url = 'https://test_image_urls.matplotlib.org/'

		X, Y = np.meshgrid(np.arange(-5, 5, 1), np.arange(-5, 5, 1))
		Z = np.sin(Y ** 2)
		fig, ax = plt.subplots()
		im = ax.imshow(Z, interpolation='none', url=image_url)
		with io.BytesIO() as fd:
		fig.savefig(fd, format="pdf")
		with pikepdf.Pdf.open(fd) as pdf:
		annots = pdf.pages[0].Annots

		# Iteration over Annots must occur within the context manager,
		# otherwise it may fail depending on the pdf structure.
		annot = next(
		(a for a in annots if a.A.URI == image_url),
		None)
		assert annot is not None
		# Positions in points (72 per inch.)
		assert annot.Rect == [decimal.Decimal('122.4'),
		decimal.Decimal('43.2'),
		decimal.Decimal('468.4'),
		decimal.Decimal('389.2')]
		assert getattr(annot, 'QuadPoints', None) is None
		# Transform
		im.set_transform(mpl.transforms.Affine2D().skew_deg(30, 15) + ax.transData)
		with io.BytesIO() as fd:
		fig.savefig(fd, format="pdf")
		with pikepdf.Pdf.open(fd) as pdf:
		annots = pdf.pages[0].Annots

		# Iteration over Annots must occur within the context manager,
		# otherwise it may fail depending on the pdf structure.
		annot = next(
		(a for a in annots if a.A.URI == image_url),
		None)
		assert annot is not None
		# Positions in points (72 per inch.)
		assert annot.Rect[0] == decimal.Decimal('112.411830343')
		assert getattr(annot, 'QuadPoints', None) is not None
		# Positions in points (72 per inch)
		assert annot.Rect[0] == \
		annot.QuadPoints[0] - decimal.Decimal('0.00001')


		def test_glyphs_subset():
		fpath = str(_get_data_path("fonts/ttf/DejaVuSerif.ttf"))
		chars = "these should be subsetted! 1234567890"
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