# -*- coding: utf-8 -*-
import urllib
from matplotlib.path import Path
import matplotlib.font_manager as font_manager
from matplotlib.ft2font import FT2Font, KERNING_DEFAULT, LOAD_NO_HINTING, LOAD_TARGET_LIGHT
from matplotlib.mathtext import MathTextParser
import matplotlib.dviread as dviread
from matplotlib.texmanager import TexManager
import numpy as np
class TextToPath(object):
"""
A class that convert a given text to a path using ttf fonts.
"""
FONT_SCALE = 50.
DPI = 72
def __init__(self):
"""
Initialization
"""
self.mathtext_parser = MathTextParser('path')
self.tex_font_map = None
from matplotlib.cbook import maxdict
self._ps_fontd = maxdict(50)
def _get_font(self, prop):
"""
find a ttf font.
"""
fname = font_manager.findfont(prop)
font = FT2Font(str(fname))
font.set_size(self.FONT_SCALE, self.DPI)
return font
def _get_char_id(self, font, ccode):
"""
Return a unique id for the given font and character-code set.
"""
ps_name = font.get_sfnt()[(1,0,0,6)]
char_id = urllib.quote('%s-%d' % (ps_name, ccode))
return char_id
def _get_char_id_ps(self, font, ccode):
"""
Return a unique id for the given font and character-code set (for tex).
"""
ps_name = font.get_ps_font_info()[2]
char_id = urllib.quote('%s-%d' % (ps_name, ccode))
return char_id
def glyph_to_path(self, glyph, currx=0.):
"""
convert the ft2font glyph to vertices and codes.
"""
#Mostly copied from backend_svg.py.
verts, codes = [], []
for step in glyph.path:
if step[0] == 0: # MOVE_TO
verts.append((step[1], step[2]))
codes.append(Path.MOVETO)
elif step[0] == 1: # LINE_TO
verts.append((step[1], step[2]))
codes.append(Path.LINETO)
elif step[0] == 2: # CURVE3
verts.extend([(step[1], step[2]),
(step[3], step[4])])
codes.extend([Path.CURVE3, Path.CURVE3])
elif step[0] == 3: # CURVE4
verts.extend([(step[1], step[2]),
(step[3], step[4]),
(step[5], step[6])])
codes.extend([Path.CURVE4, Path.CURVE4, Path.CURVE4])
elif step[0] == 4: # ENDPOLY
verts.append((0, 0,))
codes.append(Path.CLOSEPOLY)
verts = [(x+currx, y) for (x,y) in verts]
return verts, codes
def get_text_path(self, prop, s, ismath=False, usetex=False):
"""
convert text *s* to path (a tuple of vertices and codes for matplotlib.math.Path).
*prop*
font property
*s*
text to be converted
*usetex*
If True, use matplotlib usetex mode.
*ismath*
If True, use mathtext parser. Effective only if usetex == False.
"""
if usetex==False:
if ismath == False:
font = self._get_font(prop)
glyph_info, glyph_map, rects = self.get_glyphs_with_font(font, s)
else:
glyph_info, glyph_map, rects = self.get_glyphs_mathtext(prop, s)
else:
glyph_info, glyph_map, rects = self.get_glyphs_tex(prop, s)
verts, codes = [], []
for glyph_id, xposition, yposition, scale in glyph_info:
verts1, codes1 = glyph_map[glyph_id]
if verts1:
verts1 = np.array(verts1)*scale + [xposition, yposition]
verts.extend(verts1)
codes.extend(codes1)
for verts1, codes1 in rects:
verts.extend(verts1)
codes.extend(codes1)
return verts, codes
def get_glyphs_with_font(self, font, s, glyph_map=None):
"""
convert the string *s* to vertices and codes using the
provided ttf font.
"""
# Mostly copied from backend_svg.py.
cmap = font.get_charmap()
lastgind = None
currx = 0
xpositions = []
glyph_ids = []
if glyph_map is None:
glyph_map = dict()
# I'm not sure if I get kernings right. Needs to be verified. -JJL
for c in s:
ccode = ord(c)
gind = cmap.get(ccode)
if gind is None:
ccode = ord('?')
gind = 0
if lastgind is not None:
kern = font.get_kerning(lastgind, gind, KERNING_DEFAULT)
else:
kern = 0
glyph = font.load_char(ccode, flags=LOAD_NO_HINTING)
horiz_advance = (glyph.linearHoriAdvance / 65536.0)
char_id = self._get_char_id(font, ccode)
if not char_id in glyph_map:
glyph_map[char_id] = self.glyph_to_path(glyph)
currx += (kern / 64.0)
xpositions.append(currx)
glyph_ids.append(char_id)
currx += horiz_advance
lastgind = gind
ypositions = [0] * len(xpositions)
sizes = [1.] * len(xpositions)
rects = []
return zip(glyph_ids, xpositions, ypositions, sizes), glyph_map, rects
def get_glyphs_mathtext(self, prop, s):
"""
convert the string *s* to vertices and codes by parsing it with mathtext.
"""
prop = prop.copy()
prop.set_size(self.FONT_SCALE)
width, height, descent, glyphs, rects = self.mathtext_parser.parse(
s, self.DPI, prop)
glyph_map = dict()
xpositions = []
ypositions = []
glyph_ids = []
sizes = []
currx, curry = 0, 0
for font, fontsize, s, ox, oy in glyphs:
ccode = ord(s)
char_id = self._get_char_id(font, ccode)
if not char_id in glyph_map:
font.clear()
font.set_size(self.FONT_SCALE, self.DPI)
glyph = font.load_char(ccode, flags=LOAD_NO_HINTING)
glyph_map[char_id] = self.glyph_to_path(glyph)
xpositions.append(ox)
ypositions.append(oy)
glyph_ids.append(char_id)
size = fontsize / self.FONT_SCALE
sizes.append(size)
myrects = []
for ox, oy, w, h in rects:
vert1=[(ox, oy), (ox, oy+h), (ox+w, oy+h), (ox+w, oy), (ox, oy), (0,0)]
code1 = [Path.MOVETO,
Path.LINETO, Path.LINETO, Path.LINETO, Path.LINETO,
Path.CLOSEPOLY]
myrects.append((vert1, code1))
return zip(glyph_ids, xpositions, ypositions, sizes), glyph_map, myrects
def get_glyphs_tex(self, prop, s):
"""
convert the string *s* to vertices and codes using matplotlib's usetex mode.
"""
# codes are modstly borrowed from pdf backend.
texmanager = TexManager()
if self.tex_font_map is None:
self.tex_font_map = dviread.PsfontsMap(dviread.find_tex_file('pdftex.map'))
fontsize = prop.get_size_in_points()
if hasattr(texmanager, "get_dvi"): #
dvifilelike = texmanager.get_dvi(s, self.FONT_SCALE)
dvi = dviread.DviFromFileLike(dvifilelike, self.DPI)
else:
dvifile = texmanager.make_dvi(s, self.FONT_SCALE)
dvi = dviread.Dvi(dvifile, self.DPI)
page = iter(dvi).next()
dvi.close()
glyph_ids, xpositions, ypositions, sizes = [], [], [], []
glyph_map = dict()
# Gather font information and do some setup for combining
# characters into strings.
#oldfont, seq = None, []
for x1, y1, dvifont, glyph, width in page.text:
font_and_encoding = self._ps_fontd.get(dvifont.texname)
if font_and_encoding is None:
font_bunch = self.tex_font_map[dvifont.texname]
font = FT2Font(font_bunch.filename)
if font_bunch.encoding:
enc = dviread.Encoding(font_bunch.encoding)
else:
enc = None
self._ps_fontd[dvifont.texname] = font, enc
else:
font, enc = font_and_encoding
ft2font_flag = LOAD_TARGET_LIGHT
if enc:
ng = font.get_name_index(enc.encoding[glyph])
else:
ng = glyph
char_id = self._get_char_id_ps(font, ng)
if not char_id in glyph_map:
font.clear()
font.set_size(self.FONT_SCALE, self.DPI)
if ng == 0:
# While 0 is a valid index (e.g., "-", "\Gamma"),
# font.load_glyph(0) does not seem to work. This
# may not be a general solution.
glyph0 = font.load_glyph(128, flags=ft2font_flag)
else:
glyph0 = font.load_glyph(ng, flags=ft2font_flag)
glyph_map[char_id] = self.glyph_to_path(glyph0)
glyph_ids.append(char_id)
xpositions.append(x1)
ypositions.append(y1)
sizes.append(dvifont.size/self.FONT_SCALE)
myrects = []
for ox, oy, h, w in page.boxes:
vert1=[(ox, oy), (ox+w, oy), (ox+w, oy+h), (ox, oy+h), (ox, oy), (0,0)]
code1 = [Path.MOVETO,
Path.LINETO, Path.LINETO, Path.LINETO, Path.LINETO,
Path.CLOSEPOLY]
myrects.append((vert1, code1))
return zip(glyph_ids, xpositions, ypositions, sizes), glyph_map, myrects
from matplotlib.font_manager import FontProperties
from matplotlib import rcParams
from matplotlib.transforms import Affine2D
text_to_path = TextToPath()
class TextPath(Path):
"""
Create a path from the text.
"""
def __init__(self, xy, s, size=None, prop=None,
_interpolation_steps=1, usetex=False,
*kl, **kwargs):
"""
Create a path from the text. No support for TeX yet. Note that
it simply is a path, not an artist. You need to use the
PathPatch (or other artists) to draw this path onto the
canvas.
xy : position of the text.
s : text
size : font size
prop : font property
"""
if prop is None:
prop = FontProperties()
if size is None:
size = prop.get_size_in_points()
self._xy = xy
self.set_size(size)
self._cached_vertices = None
self._vertices, self._codes = self.text_get_vertices_codes(prop, s, usetex=usetex)
self.should_simplify = False
self.simplify_threshold = rcParams['path.simplify_threshold']
self.has_nonfinite = False
self._interpolation_steps = _interpolation_steps
def set_size(self, size):
"""
set the size of the text
"""
self._size = size
self._invalid = True
def get_size(self):
"""
get the size of the text
"""
return self._size
def _get_vertices(self):
"""
Return the cached path after updating it if necessary.
"""
self._revalidate_path()
return self._cached_vertices
def _get_codes(self):
"""
Return the codes
"""
return self._codes
vertices = property(_get_vertices)
codes = property(_get_codes)
def _revalidate_path(self):
"""
update the path if necessary.
The path for the text is initially create with the font size
of FONT_SCALE, and this path is rescaled to other size when
necessary.
"""
if self._invalid or \
(self._cached_vertices is None):
tr = Affine2D().scale(self._size/text_to_path.FONT_SCALE,
self._size/text_to_path.FONT_SCALE).translate(*self._xy)
self._cached_vertices = tr.transform(self._vertices)
self._invalid = False
def is_math_text(self, s):
"""
Returns True if the given string *s* contains any mathtext.
"""
# copied from Text.is_math_text -JJL
# Did we find an even number of non-escaped dollar signs?
# If so, treat is as math text.
dollar_count = s.count(r'$') - s.count(r'\$')
even_dollars = (dollar_count > 0 and dollar_count % 2 == 0)
if rcParams['text.usetex']:
return s, 'TeX'
if even_dollars:
return s, True
else:
return s.replace(r'\$', '$'), False
def text_get_vertices_codes(self, prop, s, usetex):
"""
convert the string *s* to vertices and codes using the
provided font property *prop*. Mostly copied from
backend_svg.py.
"""
if usetex:
verts, codes = text_to_path.get_text_path(prop, s, usetex=True)
else:
clean_line, ismath = self.is_math_text(s)
verts, codes = text_to_path.get_text_path(prop, clean_line, ismath=ismath)
return verts, codes
