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Source code for matplotlib.backends.backend_svg

from collections import OrderedDict

import base64
import gzip
import hashlib
import io
import logging
import re
import uuid

import numpy as np

from matplotlib import cbook, __version__, rcParams
from matplotlib.backend_bases import (
     _Backend, FigureCanvasBase, FigureManagerBase, RendererBase)
from matplotlib.backends.backend_mixed import MixedModeRenderer
from matplotlib.colors import rgb2hex
from matplotlib.font_manager import findfont, get_font
from matplotlib.ft2font import LOAD_NO_HINTING
from matplotlib.mathtext import MathTextParser
from matplotlib.path import Path
from matplotlib import _path
from matplotlib.transforms import Affine2D, Affine2DBase
from matplotlib import _png

_log = logging.getLogger(__name__)

backend_version = __version__

# ----------------------------------------------------------------------
# SimpleXMLWriter class
# Based on an original by Fredrik Lundh, but modified here to:
#   1. Support modern Python idioms
#   2. Remove encoding support (it's handled by the file writer instead)
#   3. Support proper indentation
#   4. Minify things a little bit

# --------------------------------------------------------------------
# The SimpleXMLWriter module is
# Copyright (c) 2001-2004 by Fredrik Lundh
# By obtaining, using, and/or copying this software and/or its
# associated documentation, you agree that you have read, understood,
# and will comply with the following terms and conditions:
# Permission to use, copy, modify, and distribute this software and
# its associated documentation for any purpose and without fee is
# hereby granted, provided that the above copyright notice appears in
# all copies, and that both that copyright notice and this permission
# notice appear in supporting documentation, and that the name of
# Secret Labs AB or the author not be used in advertising or publicity
# pertaining to distribution of the software without specific, written
# prior permission.
# --------------------------------------------------------------------

[docs]def escape_cdata(s): s = s.replace("&", "&amp;") s = s.replace("<", "&lt;") s = s.replace(">", "&gt;") return s
_escape_xml_comment = re.compile(r'-(?=-)')
[docs]def escape_comment(s): s = escape_cdata(s) return _escape_xml_comment.sub('- ', s)
[docs]def escape_attrib(s): s = s.replace("&", "&amp;") s = s.replace("'", "&apos;") s = s.replace("\"", "&quot;") s = s.replace("<", "&lt;") s = s.replace(">", "&gt;") return s
[docs]def short_float_fmt(x): """ Create a short string representation of a float, which is %f formatting with trailing zeros and the decimal point removed. """ return '{0:f}'.format(x).rstrip('0').rstrip('.')
## # XML writer class. # # @param file A file or file-like object. This object must implement # a <b>write</b> method that takes an 8-bit string.
[docs]class XMLWriter(object): def __init__(self, file): self.__write = file.write if hasattr(file, "flush"): self.flush = file.flush self.__open = 0 # true if start tag is open self.__tags = [] self.__data = [] self.__indentation = " " * 64 def __flush(self, indent=True): # flush internal buffers if self.__open: if indent: self.__write(">\n") else: self.__write(">") self.__open = 0 if self.__data: data = ''.join(self.__data) self.__write(escape_cdata(data)) self.__data = [] ## Opens a new element. Attributes can be given as keyword # arguments, or as a string/string dictionary. The method returns # an opaque identifier that can be passed to the <b>close</b> # method, to close all open elements up to and including this one. # # @param tag Element tag. # @param attrib Attribute dictionary. Alternatively, attributes # can be given as keyword arguments. # @return An element identifier.
[docs] def start(self, tag, attrib={}, **extra): self.__flush() tag = escape_cdata(tag) self.__data = [] self.__tags.append(tag) self.__write(self.__indentation[:len(self.__tags) - 1]) self.__write("<%s" % tag) for k, v in sorted({**attrib, **extra}.items()): if not v == '': k = escape_cdata(k) v = escape_attrib(v) self.__write(" %s=\"%s\"" % (k, v)) self.__open = 1 return len(self.__tags)-1
## # Adds a comment to the output stream. # # @param comment Comment text, as a Unicode string.
[docs] def comment(self, comment): self.__flush() self.__write(self.__indentation[:len(self.__tags)]) self.__write("<!-- %s -->\n" % escape_comment(comment))
## # Adds character data to the output stream. # # @param text Character data, as a Unicode string.
[docs] def data(self, text): self.__data.append(text)
## # Closes the current element (opened by the most recent call to # <b>start</b>). # # @param tag Element tag. If given, the tag must match the start # tag. If omitted, the current element is closed.
[docs] def end(self, tag=None, indent=True): if tag: assert self.__tags, "unbalanced end(%s)" % tag assert escape_cdata(tag) == self.__tags[-1],\ "expected end(%s), got %s" % (self.__tags[-1], tag) else: assert self.__tags, "unbalanced end()" tag = self.__tags.pop() if self.__data: self.__flush(indent) elif self.__open: self.__open = 0 self.__write("/>\n") return if indent: self.__write(self.__indentation[:len(self.__tags)]) self.__write("</%s>\n" % tag)
## # Closes open elements, up to (and including) the element identified # by the given identifier. # # @param id Element identifier, as returned by the <b>start</b> method.
[docs] def close(self, id): while len(self.__tags) > id: self.end()
## # Adds an entire element. This is the same as calling <b>start</b>, # <b>data</b>, and <b>end</b> in sequence. The <b>text</b> argument # can be omitted.
[docs] def element(self, tag, text=None, attrib={}, **extra): self.start(*(tag, attrib), **extra) if text: self.end(indent=False)
## # Flushes the output stream.
[docs] def flush(self): pass # replaced by the constructor
# ----------------------------------------------------------------------
[docs]def generate_transform(transform_list=[]): if len(transform_list): output = io.StringIO() for type, value in transform_list: if (type == 'scale' and (value == (1,) or value == (1, 1)) or type == 'translate' and value == (0, 0) or type == 'rotate' and value == (0,)): continue if type == 'matrix' and isinstance(value, Affine2DBase): value = value.to_values() output.write('%s(%s)' % ( type, ' '.join(short_float_fmt(x) for x in value))) return output.getvalue() return ''
[docs]def generate_css(attrib={}): if attrib: output = io.StringIO() attrib = sorted(attrib.items()) for k, v in attrib: k = escape_attrib(k) v = escape_attrib(v) output.write("%s:%s;" % (k, v)) return output.getvalue() return ''
_capstyle_d = {'projecting' : 'square', 'butt' : 'butt', 'round': 'round',}
[docs]class RendererSVG(RendererBase): def __init__(self, width, height, svgwriter, basename=None, image_dpi=72): self.width = width self.height = height self.writer = XMLWriter(svgwriter) self.image_dpi = image_dpi # the actual dpi we want to rasterize stuff with self._groupd = {} if not rcParams['svg.image_inline']: assert basename is not None self.basename = basename self._imaged = {} self._clipd = OrderedDict() self._char_defs = {} self._markers = {} self._path_collection_id = 0 self._imaged = {} self._hatchd = OrderedDict() self._has_gouraud = False self._n_gradients = 0 self._fonts = OrderedDict() self.mathtext_parser = MathTextParser('SVG') RendererBase.__init__(self) self._glyph_map = dict() str_height = short_float_fmt(height) str_width = short_float_fmt(width) svgwriter.write(svgProlog) self._start_id = self.writer.start( 'svg', width='%spt' % str_width, height='%spt' % str_height, viewBox='0 0 %s %s' % (str_width, str_height), xmlns="", version="1.1", attrib={'xmlns:xlink': ""}) self._write_default_style()
[docs] def finalize(self): self._write_clips() self._write_hatches() self._write_svgfonts() self.writer.close(self._start_id) self.writer.flush()
def _write_default_style(self): writer = self.writer default_style = generate_css({ 'stroke-linejoin': 'round', 'stroke-linecap': 'butt'}) writer.start('defs') writer.start('style', type='text/css')'*{%s}\n' % default_style) writer.end('style') writer.end('defs') def _make_id(self, type, content): salt = rcParams['svg.hashsalt'] if salt is None: salt = str(uuid.uuid4()) m = hashlib.md5() m.update(salt.encode('utf8')) m.update(str(content).encode('utf8')) return '%s%s' % (type, m.hexdigest()[:10]) def _make_flip_transform(self, transform): return (transform + Affine2D() .scale(1.0, -1.0) .translate(0.0, self.height)) def _get_font(self, prop): fname = findfont(prop) font = get_font(fname) font.clear() size = prop.get_size_in_points() font.set_size(size, 72.0) return font def _get_hatch(self, gc, rgbFace): """ Create a new hatch pattern """ if rgbFace is not None: rgbFace = tuple(rgbFace) edge = gc.get_hatch_color() if edge is not None: edge = tuple(edge) dictkey = (gc.get_hatch(), rgbFace, edge) oid = self._hatchd.get(dictkey) if oid is None: oid = self._make_id('h', dictkey) self._hatchd[dictkey] = ((gc.get_hatch_path(), rgbFace, edge), oid) else: _, oid = oid return oid def _write_hatches(self): if not len(self._hatchd): return HATCH_SIZE = 72 writer = self.writer writer.start('defs') for (path, face, stroke), oid in self._hatchd.values(): writer.start( 'pattern', id=oid, patternUnits="userSpaceOnUse", x="0", y="0", width=str(HATCH_SIZE), height=str(HATCH_SIZE)) path_data = self._convert_path( path, Affine2D().scale(HATCH_SIZE).scale(1.0, -1.0).translate(0, HATCH_SIZE), simplify=False) if face is None: fill = 'none' else: fill = rgb2hex(face) writer.element( 'rect', x="0", y="0", width=str(HATCH_SIZE+1), height=str(HATCH_SIZE+1), fill=fill) writer.element( 'path', d=path_data, style=generate_css({ 'fill': rgb2hex(stroke), 'stroke': rgb2hex(stroke), 'stroke-width': str(rcParams['hatch.linewidth']), 'stroke-linecap': 'butt', 'stroke-linejoin': 'miter' }) ) writer.end('pattern') writer.end('defs') def _get_style_dict(self, gc, rgbFace): """ return the style string. style is generated from the GraphicsContext and rgbFace """ attrib = {} forced_alpha = gc.get_forced_alpha() if gc.get_hatch() is not None: attrib['fill'] = "url(#%s)" % self._get_hatch(gc, rgbFace) if rgbFace is not None and len(rgbFace) == 4 and rgbFace[3] != 1.0 and not forced_alpha: attrib['fill-opacity'] = short_float_fmt(rgbFace[3]) else: if rgbFace is None: attrib['fill'] = 'none' else: if tuple(rgbFace[:3]) != (0, 0, 0): attrib['fill'] = rgb2hex(rgbFace) if len(rgbFace) == 4 and rgbFace[3] != 1.0 and not forced_alpha: attrib['fill-opacity'] = short_float_fmt(rgbFace[3]) if forced_alpha and gc.get_alpha() != 1.0: attrib['opacity'] = short_float_fmt(gc.get_alpha()) offset, seq = gc.get_dashes() if seq is not None: attrib['stroke-dasharray'] = ','.join([short_float_fmt(val) for val in seq]) attrib['stroke-dashoffset'] = short_float_fmt(float(offset)) linewidth = gc.get_linewidth() if linewidth: rgb = gc.get_rgb() attrib['stroke'] = rgb2hex(rgb) if not forced_alpha and rgb[3] != 1.0: attrib['stroke-opacity'] = short_float_fmt(rgb[3]) if linewidth != 1.0: attrib['stroke-width'] = short_float_fmt(linewidth) if gc.get_joinstyle() != 'round': attrib['stroke-linejoin'] = gc.get_joinstyle() if gc.get_capstyle() != 'butt': attrib['stroke-linecap'] = _capstyle_d[gc.get_capstyle()] return attrib def _get_style(self, gc, rgbFace): return generate_css(self._get_style_dict(gc, rgbFace)) def _get_clip(self, gc): cliprect = gc.get_clip_rectangle() clippath, clippath_trans = gc.get_clip_path() if clippath is not None: clippath_trans = self._make_flip_transform(clippath_trans) dictkey = (id(clippath), str(clippath_trans)) elif cliprect is not None: x, y, w, h = cliprect.bounds y = self.height-(y+h) dictkey = (x, y, w, h) else: return None clip = self._clipd.get(dictkey) if clip is None: oid = self._make_id('p', dictkey) if clippath is not None: self._clipd[dictkey] = ((clippath, clippath_trans), oid) else: self._clipd[dictkey] = (dictkey, oid) else: clip, oid = clip return oid def _write_clips(self): if not len(self._clipd): return writer = self.writer writer.start('defs') for clip, oid in self._clipd.values(): writer.start('clipPath', id=oid) if len(clip) == 2: clippath, clippath_trans = clip path_data = self._convert_path(clippath, clippath_trans, simplify=False) writer.element('path', d=path_data) else: x, y, w, h = clip writer.element( 'rect', x=short_float_fmt(x), y=short_float_fmt(y), width=short_float_fmt(w), height=short_float_fmt(h)) writer.end('clipPath') writer.end('defs') def _write_svgfonts(self): if not rcParams['svg.fonttype'] == 'svgfont': return writer = self.writer writer.start('defs') for font_fname, chars in self._fonts.items(): font = get_font(font_fname) font.set_size(72, 72) sfnt = font.get_sfnt() writer.start('font', id=sfnt[1, 0, 0, 4].decode("mac_roman")) writer.element( 'font-face', attrib={ 'font-family': font.family_name, 'font-style': font.style_name.lower(), 'units-per-em': '72', 'bbox': ' '.join( short_float_fmt(x / 64.0) for x in font.bbox)}) for char in chars: glyph = font.load_char(char, flags=LOAD_NO_HINTING) verts, codes = font.get_path() path = Path(verts, codes) path_data = self._convert_path(path) # name = font.get_glyph_name(char) writer.element( 'glyph', d=path_data, attrib={ # 'glyph-name': name, 'unicode': chr(char), 'horiz-adv-x': short_float_fmt(glyph.linearHoriAdvance / 65536.0)}) writer.end('font') writer.end('defs')
[docs] def open_group(self, s, gid=None): """ Open a grouping element with label *s*. If *gid* is given, use *gid* as the id of the group. """ if gid: self.writer.start('g', id=gid) else: self._groupd[s] = self._groupd.get(s, 0) + 1 self.writer.start('g', id="%s_%d" % (s, self._groupd[s]))
[docs] def close_group(self, s): self.writer.end('g')
[docs] def option_image_nocomposite(self): """ return whether to generate a composite image from multiple images on a set of axes """ return not rcParams['image.composite_image']
def _convert_path(self, path, transform=None, clip=None, simplify=None, sketch=None): if clip: clip = (0.0, 0.0, self.width, self.height) else: clip = None return _path.convert_to_string( path, transform, clip, simplify, sketch, 6, [b'M', b'L', b'Q', b'C', b'z'], False).decode('ascii')
[docs] def draw_path(self, gc, path, transform, rgbFace=None): trans_and_flip = self._make_flip_transform(transform) clip = (rgbFace is None and gc.get_hatch_path() is None) simplify = path.should_simplify and clip path_data = self._convert_path( path, trans_and_flip, clip=clip, simplify=simplify, sketch=gc.get_sketch_params()) attrib = {} attrib['style'] = self._get_style(gc, rgbFace) clipid = self._get_clip(gc) if clipid is not None: attrib['clip-path'] = 'url(#%s)' % clipid if gc.get_url() is not None: self.writer.start('a', {'xlink:href': gc.get_url()}) self.writer.element('path', d=path_data, attrib=attrib) if gc.get_url() is not None: self.writer.end('a')
[docs] def draw_markers(self, gc, marker_path, marker_trans, path, trans, rgbFace=None): if not len(path.vertices): return writer = self.writer path_data = self._convert_path( marker_path, marker_trans + Affine2D().scale(1.0, -1.0), simplify=False) style = self._get_style_dict(gc, rgbFace) dictkey = (path_data, generate_css(style)) oid = self._markers.get(dictkey) style = generate_css({k: v for k, v in style.items() if k.startswith('stroke')}) if oid is None: oid = self._make_id('m', dictkey) writer.start('defs') writer.element('path', id=oid, d=path_data, style=style) writer.end('defs') self._markers[dictkey] = oid attrib = {} clipid = self._get_clip(gc) if clipid is not None: attrib['clip-path'] = 'url(#%s)' % clipid writer.start('g', attrib=attrib) trans_and_flip = self._make_flip_transform(trans) attrib = {'xlink:href': '#%s' % oid} clip = (0, 0, self.width*72, self.height*72) for vertices, code in path.iter_segments( trans_and_flip, clip=clip, simplify=False): if len(vertices): x, y = vertices[-2:] attrib['x'] = short_float_fmt(x) attrib['y'] = short_float_fmt(y) attrib['style'] = self._get_style(gc, rgbFace) writer.element('use', attrib=attrib) writer.end('g')
[docs] def draw_path_collection(self, gc, master_transform, paths, all_transforms, offsets, offsetTrans, facecolors, edgecolors, linewidths, linestyles, antialiaseds, urls, offset_position): # Is the optimization worth it? Rough calculation: # cost of emitting a path in-line is # (len_path + 5) * uses_per_path # cost of definition+use is # (len_path + 3) + 9 * uses_per_path len_path = len(paths[0].vertices) if len(paths) > 0 else 0 uses_per_path = self._iter_collection_uses_per_path( paths, all_transforms, offsets, facecolors, edgecolors) should_do_optimization = \ len_path + 9 * uses_per_path + 3 < (len_path + 5) * uses_per_path if not should_do_optimization: return RendererBase.draw_path_collection( self, gc, master_transform, paths, all_transforms, offsets, offsetTrans, facecolors, edgecolors, linewidths, linestyles, antialiaseds, urls, offset_position) writer = self.writer path_codes = [] writer.start('defs') for i, (path, transform) in enumerate(self._iter_collection_raw_paths( master_transform, paths, all_transforms)): transform = Affine2D(transform.get_matrix()).scale(1.0, -1.0) d = self._convert_path(path, transform, simplify=False) oid = 'C%x_%x_%s' % (self._path_collection_id, i, self._make_id('', d)) writer.element('path', id=oid, d=d) path_codes.append(oid) writer.end('defs') for xo, yo, path_id, gc0, rgbFace in self._iter_collection( gc, master_transform, all_transforms, path_codes, offsets, offsetTrans, facecolors, edgecolors, linewidths, linestyles, antialiaseds, urls, offset_position): clipid = self._get_clip(gc0) url = gc0.get_url() if url is not None: writer.start('a', attrib={'xlink:href': url}) if clipid is not None: writer.start('g', attrib={'clip-path': 'url(#%s)' % clipid}) attrib = { 'xlink:href': '#%s' % path_id, 'x': short_float_fmt(xo), 'y': short_float_fmt(self.height - yo), 'style': self._get_style(gc0, rgbFace) } writer.element('use', attrib=attrib) if clipid is not None: writer.end('g') if url is not None: writer.end('a') self._path_collection_id += 1
[docs] def draw_gouraud_triangle(self, gc, points, colors, trans): # This uses a method described here: # # # # that uses three overlapping linear gradients to simulate a # Gouraud triangle. Each gradient goes from fully opaque in # one corner to fully transparent along the opposite edge. # The line between the stop points is perpendicular to the # opposite edge. Underlying these three gradients is a solid # triangle whose color is the average of all three points. writer = self.writer if not self._has_gouraud: self._has_gouraud = True writer.start( 'filter', id='colorAdd') writer.element( 'feComposite', attrib={'in': 'SourceGraphic'}, in2='BackgroundImage', operator='arithmetic', k2="1", k3="1") writer.end('filter') # feColorMatrix filter to correct opacity writer.start( 'filter', id='colorMat') writer.element( 'feColorMatrix', attrib={'type': 'matrix'}, values='1 0 0 0 0 \n0 1 0 0 0 \n0 0 1 0 0' + ' \n1 1 1 1 0 \n0 0 0 0 1 ') writer.end('filter') avg_color = np.sum(colors[:, :], axis=0) / 3.0 # Just skip fully-transparent triangles if avg_color[-1] == 0.0: return trans_and_flip = self._make_flip_transform(trans) tpoints = trans_and_flip.transform(points) writer.start('defs') for i in range(3): x1, y1 = tpoints[i] x2, y2 = tpoints[(i + 1) % 3] x3, y3 = tpoints[(i + 2) % 3] c = colors[i][:] if x2 == x3: xb = x2 yb = y1 elif y2 == y3: xb = x1 yb = y2 else: m1 = (y2 - y3) / (x2 - x3) b1 = y2 - (m1 * x2) m2 = -(1.0 / m1) b2 = y1 - (m2 * x1) xb = (-b1 + b2) / (m1 - m2) yb = m2 * xb + b2 writer.start( 'linearGradient', id="GR%x_%d" % (self._n_gradients, i), gradientUnits="userSpaceOnUse", x1=short_float_fmt(x1), y1=short_float_fmt(y1), x2=short_float_fmt(xb), y2=short_float_fmt(yb)) writer.element( 'stop', offset='1', style=generate_css({'stop-color': rgb2hex(avg_color), 'stop-opacity': short_float_fmt(c[-1])})) writer.element( 'stop', offset='0', style=generate_css({'stop-color': rgb2hex(c), 'stop-opacity': "0"})) writer.end('linearGradient') writer.end('defs') # triangle formation using "path" dpath = "M " + short_float_fmt(x1)+',' + short_float_fmt(y1) dpath += " L " + short_float_fmt(x2) + ',' + short_float_fmt(y2) dpath += " " + short_float_fmt(x3) + ',' + short_float_fmt(y3) + " Z" writer.element( 'path', attrib={'d': dpath, 'fill': rgb2hex(avg_color), 'fill-opacity': '1', 'shape-rendering': "crispEdges"}) writer.start( 'g', attrib={'stroke': "none", 'stroke-width': "0", 'shape-rendering': "crispEdges", 'filter': "url(#colorMat)"}) writer.element( 'path', attrib={'d': dpath, 'fill': 'url(#GR%x_0)' % self._n_gradients, 'shape-rendering': "crispEdges"}) writer.element( 'path', attrib={'d': dpath, 'fill': 'url(#GR%x_1)' % self._n_gradients, 'filter': 'url(#colorAdd)', 'shape-rendering': "crispEdges"}) writer.element( 'path', attrib={'d': dpath, 'fill': 'url(#GR%x_2)' % self._n_gradients, 'filter': 'url(#colorAdd)', 'shape-rendering': "crispEdges"}) writer.end('g') self._n_gradients += 1
[docs] def draw_gouraud_triangles(self, gc, triangles_array, colors_array, transform): attrib = {} clipid = self._get_clip(gc) if clipid is not None: attrib['clip-path'] = 'url(#%s)' % clipid self.writer.start('g', attrib=attrib) transform = transform.frozen() for tri, col in zip(triangles_array, colors_array): self.draw_gouraud_triangle(gc, tri, col, transform) self.writer.end('g')
[docs] def option_scale_image(self): return True
[docs] def get_image_magnification(self): return self.image_dpi / 72.0
[docs] def draw_image(self, gc, x, y, im, transform=None): h, w = im.shape[:2] if w == 0 or h == 0: return attrib = {} clipid = self._get_clip(gc) if clipid is not None: # Can't apply clip-path directly to the image because the # image has a transformation, which would also be applied # to the clip-path self.writer.start('g', attrib={'clip-path': 'url(#%s)' % clipid}) oid = gc.get_gid() url = gc.get_url() if url is not None: self.writer.start('a', attrib={'xlink:href': url}) if rcParams['svg.image_inline']: bytesio = io.BytesIO() _png.write_png(im, bytesio) oid = oid or self._make_id('image', bytesio.getvalue()) attrib['xlink:href'] = ( "data:image/png;base64,\n" + base64.b64encode(bytesio.getvalue()).decode('ascii')) else: self._imaged[self.basename] = self._imaged.get(self.basename, 0) + 1 filename = '%s.image%d.png'%(self.basename, self._imaged[self.basename])'Writing image file for inclusion: %s', filename) _png.write_png(im, filename) oid = oid or 'Im_' + self._make_id('image', filename) attrib['xlink:href'] = filename attrib['id'] = oid if transform is None: w = 72.0 * w / self.image_dpi h = 72.0 * h / self.image_dpi self.writer.element( 'image', transform=generate_transform([ ('scale', (1, -1)), ('translate', (0, -h))]), x=short_float_fmt(x), y=short_float_fmt(-(self.height - y - h)), width=short_float_fmt(w), height=short_float_fmt(h), attrib=attrib) else: alpha = gc.get_alpha() if alpha != 1.0: attrib['opacity'] = short_float_fmt(alpha) flipped = ( Affine2D().scale(1.0 / w, 1.0 / h) + transform + Affine2D() .translate(x, y) .scale(1.0, -1.0) .translate(0.0, self.height)) attrib['transform'] = generate_transform( [('matrix', flipped.frozen())]) self.writer.element( 'image', width=short_float_fmt(w), height=short_float_fmt(h), attrib=attrib) if url is not None: self.writer.end('a') if clipid is not None: self.writer.end('g')
def _adjust_char_id(self, char_id): return char_id.replace("%20", "_") def _draw_text_as_path(self, gc, x, y, s, prop, angle, ismath, mtext=None): """ draw the text by converting them to paths using textpath module. Parameters ---------- prop : `matplotlib.font_manager.FontProperties` font property s : str text to be converted usetex : bool If True, use matplotlib usetex mode. ismath : bool If True, use mathtext parser. If "TeX", use *usetex* mode. """ writer = self.writer writer.comment(s) glyph_map=self._glyph_map text2path = self._text2path color = rgb2hex(gc.get_rgb()) fontsize = prop.get_size_in_points() style = {} if color != '#000000': style['fill'] = color alpha = gc.get_alpha() if gc.get_forced_alpha() else gc.get_rgb()[3] if alpha != 1: style['opacity'] = short_float_fmt(alpha) if not ismath: font = text2path._get_font(prop) _glyphs = text2path.get_glyphs_with_font( font, s, glyph_map=glyph_map, return_new_glyphs_only=True) glyph_info, glyph_map_new, rects = _glyphs if glyph_map_new: writer.start('defs') for char_id, glyph_path in glyph_map_new.items(): path = Path(*glyph_path) path_data = self._convert_path(path, simplify=False) writer.element('path', id=char_id, d=path_data) writer.end('defs') glyph_map.update(glyph_map_new) attrib = {} attrib['style'] = generate_css(style) font_scale = fontsize / text2path.FONT_SCALE attrib['transform'] = generate_transform([ ('translate', (x, y)), ('rotate', (-angle,)), ('scale', (font_scale, -font_scale))]) writer.start('g', attrib=attrib) for glyph_id, xposition, yposition, scale in glyph_info: attrib={'xlink:href': '#%s' % glyph_id} if xposition != 0.0: attrib['x'] = short_float_fmt(xposition) if yposition != 0.0: attrib['y'] = short_float_fmt(yposition) writer.element( 'use', attrib=attrib) writer.end('g') else: if ismath == "TeX": _glyphs = text2path.get_glyphs_tex(prop, s, glyph_map=glyph_map, return_new_glyphs_only=True) else: _glyphs = text2path.get_glyphs_mathtext(prop, s, glyph_map=glyph_map, return_new_glyphs_only=True) glyph_info, glyph_map_new, rects = _glyphs # we store the character glyphs w/o flipping. Instead, the # coordinate will be flipped when this characters are # used. if glyph_map_new: writer.start('defs') for char_id, glyph_path in glyph_map_new.items(): char_id = self._adjust_char_id(char_id) # Some characters are blank if not len(glyph_path[0]): path_data = "" else: path = Path(*glyph_path) path_data = self._convert_path(path, simplify=False) writer.element('path', id=char_id, d=path_data) writer.end('defs') glyph_map.update(glyph_map_new) attrib = {} font_scale = fontsize / text2path.FONT_SCALE attrib['style'] = generate_css(style) attrib['transform'] = generate_transform([ ('translate', (x, y)), ('rotate', (-angle,)), ('scale', (font_scale, -font_scale))]) writer.start('g', attrib=attrib) for char_id, xposition, yposition, scale in glyph_info: char_id = self._adjust_char_id(char_id) writer.element( 'use', transform=generate_transform([ ('translate', (xposition, yposition)), ('scale', (scale,)), ]), attrib={'xlink:href': '#%s' % char_id}) for verts, codes in rects: path = Path(verts, codes) path_data = self._convert_path(path, simplify=False) writer.element('path', d=path_data) writer.end('g') def _draw_text_as_text(self, gc, x, y, s, prop, angle, ismath, mtext=None): writer = self.writer color = rgb2hex(gc.get_rgb()) style = {} if color != '#000000': style['fill'] = color alpha = gc.get_alpha() if gc.get_forced_alpha() else gc.get_rgb()[3] if alpha != 1: style['opacity'] = short_float_fmt(alpha) if not ismath: font = self._get_font(prop) font.set_text(s, 0.0, flags=LOAD_NO_HINTING) fontsize = prop.get_size_in_points() fontfamily = font.family_name fontstyle = prop.get_style() attrib = {} # Must add "px" to workaround a Firefox bug style['font-size'] = short_float_fmt(fontsize) + 'px' style['font-family'] = str(fontfamily) style['font-style'] = prop.get_style().lower() style['font-weight'] = str(prop.get_weight()).lower() attrib['style'] = generate_css(style) if mtext and (angle == 0 or mtext.get_rotation_mode() == "anchor"): # If text anchoring can be supported, get the original # coordinates and add alignment information. # Get anchor coordinates. transform = mtext.get_transform() ax, ay = transform.transform_point(mtext.get_position()) ay = self.height - ay # Don't do vertical anchor alignment. Most applications do not # support 'alignment-baseline' yet. Apply the vertical layout # to the anchor point manually for now. angle_rad = np.deg2rad(angle) dir_vert = np.array([np.sin(angle_rad), np.cos(angle_rad)]) v_offset =, [(x - ax), (y - ay)]) ax = ax + v_offset * dir_vert[0] ay = ay + v_offset * dir_vert[1] ha_mpl_to_svg = {'left': 'start', 'right': 'end', 'center': 'middle'} style['text-anchor'] = ha_mpl_to_svg[mtext.get_ha()] attrib['x'] = short_float_fmt(ax) attrib['y'] = short_float_fmt(ay) attrib['style'] = generate_css(style) attrib['transform'] = "rotate(%s, %s, %s)" % ( short_float_fmt(-angle), short_float_fmt(ax), short_float_fmt(ay)) writer.element('text', s, attrib=attrib) else: attrib['transform'] = generate_transform([ ('translate', (x, y)), ('rotate', (-angle,))]) writer.element('text', s, attrib=attrib) if rcParams['svg.fonttype'] == 'svgfont': fontset = self._fonts.setdefault(font.fname, set()) for c in s: fontset.add(ord(c)) else: writer.comment(s) width, height, descent, svg_elements, used_characters = \ self.mathtext_parser.parse(s, 72, prop) svg_glyphs = svg_elements.svg_glyphs svg_rects = svg_elements.svg_rects attrib = {} attrib['style'] = generate_css(style) attrib['transform'] = generate_transform([ ('translate', (x, y)), ('rotate', (-angle,))]) # Apply attributes to 'g', not 'text', because we likely have some # rectangles as well with the same style and transformation. writer.start('g', attrib=attrib) writer.start('text') # Sort the characters by font, and output one tspan for each. spans = OrderedDict() for font, fontsize, thetext, new_x, new_y, metrics in svg_glyphs: style = generate_css({ 'font-size': short_float_fmt(fontsize) + 'px', 'font-family': font.family_name, 'font-style': font.style_name.lower(), 'font-weight': font.style_name.lower()}) if thetext == 32: thetext = 0xa0 # non-breaking space spans.setdefault(style, []).append((new_x, -new_y, thetext)) if rcParams['svg.fonttype'] == 'svgfont': for font, fontsize, thetext, new_x, new_y, metrics in svg_glyphs: fontset = self._fonts.setdefault(font.fname, set()) fontset.add(thetext) for style, chars in spans.items(): chars.sort() same_y = True if len(chars) > 1: last_y = chars[0][1] for i in range(1, len(chars)): if chars[i][1] != last_y: same_y = False break if same_y: ys = str(chars[0][1]) else: ys = ' '.join(str(c[1]) for c in chars) attrib = { 'style': style, 'x': ' '.join(short_float_fmt(c[0]) for c in chars), 'y': ys } writer.element( 'tspan', ''.join(chr(c[2]) for c in chars), attrib=attrib) writer.end('text') if len(svg_rects): for x, y, width, height in svg_rects: writer.element( 'rect', x=short_float_fmt(x), y=short_float_fmt(-y + height), width=short_float_fmt(width), height=short_float_fmt(height) ) writer.end('g')
[docs] def draw_tex(self, gc, x, y, s, prop, angle, ismath='TeX!', mtext=None): self._draw_text_as_path(gc, x, y, s, prop, angle, ismath="TeX")
[docs] def draw_text(self, gc, x, y, s, prop, angle, ismath=False, mtext=None): clipid = self._get_clip(gc) if clipid is not None: # Cannot apply clip-path directly to the text, because # is has a transformation self.writer.start( 'g', attrib={'clip-path': 'url(#%s)' % clipid}) if gc.get_url() is not None: self.writer.start('a', {'xlink:href': gc.get_url()}) if rcParams['svg.fonttype'] == 'path': self._draw_text_as_path(gc, x, y, s, prop, angle, ismath, mtext) else: self._draw_text_as_text(gc, x, y, s, prop, angle, ismath, mtext) if gc.get_url() is not None: self.writer.end('a') if clipid is not None: self.writer.end('g')
[docs] def flipy(self): return True
[docs] def get_canvas_width_height(self): return self.width, self.height
[docs] def get_text_width_height_descent(self, s, prop, ismath): return self._text2path.get_text_width_height_descent(s, prop, ismath)
[docs]class FigureCanvasSVG(FigureCanvasBase): filetypes = {'svg': 'Scalable Vector Graphics', 'svgz': 'Scalable Vector Graphics'} fixed_dpi = 72
[docs] def print_svg(self, filename, *args, **kwargs): with cbook.open_file_cm(filename, "w", encoding="utf-8") as fh: filename = getattr(fh, 'name', '') if not isinstance(filename, str): filename = '' if cbook.file_requires_unicode(fh): detach = False else: fh = io.TextIOWrapper(fh, 'utf-8') detach = True result = self._print_svg(filename, fh, **kwargs) # Detach underlying stream from wrapper so that it remains open in # the caller. if detach: fh.detach() return result
[docs] def print_svgz(self, filename, *args, **kwargs): with cbook.open_file_cm(filename, "wb") as fh, \ gzip.GzipFile(mode='w', fileobj=fh) as gzipwriter: return self.print_svg(gzipwriter)
def _print_svg( self, filename, fh, *, dpi=72, bbox_inches_restore=None, **kwargs): self.figure.set_dpi(72.0) width, height = self.figure.get_size_inches() w, h = width * 72, height * 72 renderer = MixedModeRenderer( self.figure, width, height, dpi, RendererSVG(w, h, fh, filename, dpi), bbox_inches_restore=bbox_inches_restore) self.figure.draw(renderer) renderer.finalize()
[docs] def get_default_filetype(self): return 'svg'
FigureManagerSVG = FigureManagerBase svgProlog = """\ <?xml version="1.0" encoding="utf-8" standalone="no"?> <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" ""> <!-- Created with matplotlib ( --> """ @_Backend.export class _BackendSVG(_Backend): FigureCanvas = FigureCanvasSVG