r""" OVERVIEW mathtext is a module for parsing TeX expressions and drawing them into a matplotlib.ft2font image buffer. You can draw from this buffer into your backend. A large set of the TeX symbols are provided (see below). Subscripting and superscripting are supported, as well as the over/under style of subscripting with \sum, \int, etc. The module uses pyparsing to parse the TeX expression, an so can handle fairly complex TeX expressions Eg, the following renders correctly s = r'$\mathcal{R}\prod_{i=\alpha\mathcal{B}}^\infty a_i\sin(2 \pi f x_i)$' Different fonts may be selected: \mathcal Calligraphic fonts \mathrm Roman (upright) font \mathit Italic font \mathtt Typewriter (monospaced) font, similar to Courier Additionally, if using the STIX fonts: \mathbb Blackboard (double-struck) font \mathcircled Circled characters \mathfrak Fraktur (Gothic-style) font \mathscr Script (cursive) font \mathsf Sans-serif font The following accents are provided: \hat, \breve, \grave, \bar, \acute, \tilde, \vec, \dot, \ddot. All of them have the same syntax, eg to make an overbar you do \bar{o} or to make an o umlaut you do \ddot{o}. The shortcuts are also provided, eg: \"o \'e \`e \~n \.x \^y The spacing elements \ , \/ and \hspace{num} are provided. \/ inserts a small space, and \hspace{num} inserts a fraction of the current fontsize. Eg, if num=0.5 and the fontsize is 12.0, hspace{0.5} inserts 6 points of space If you find TeX expressions that don't parse or render properly, please email me, but please check KNOWN ISSUES below first. REQUIREMENTS mathtext requires matplotlib.ft2font. Set BUILD_FT2FONT=True in setup.py. See BACKENDS below for a summary of availability by backend. LICENSING: The computer modern fonts this package uses are part of the BaKoMa fonts, which are (now) free for commercial and noncommercial use and redistribution; see license/LICENSE_BAKOMA in the matplotlib src distribution for redistribution requirements. USAGE: See http://matplotlib.sourceforge.net/tutorial.html#mathtext for a tutorial introduction. Any text element (xlabel, ylabel, title, text, etc) can use TeX markup, as in xlabel(r'$\Delta_i$') ^ use raw strings Math and non-math can be interpresed in the same string. E.g., r'My label $x_i$'. A large set of the TeX symbols are provided. Subscripting and superscripting are supported, as well as the over/under style of subscripting with \sum, \int, etc. Allowed TeX symbols: $ \% \AA \AE \BbbC \BbbN \BbbP \BbbQ \BbbR \BbbZ \Bumpeq \Cap \Colon \Cup \Delta \Doteq \Downarrow \Equiv \Finv \Gamma \H \Im \L \Lambda \Ldsh \Leftarrow \Leftrightarrow \Lleftarrow \Lsh \Nearrow \Nwarrow \O \OE \Omega \P \Phi \Pi \Psi \Rdsh \Re \Rightarrow \Rrightarrow \Rsh \S \Searrow \Sigma \Subset \Supset \Swarrow \Theta \Uparrow \Updownarrow \Upsilon \Vdash \Vert \Vvdash \Xi \_ \__sqrt__ \ac \acute \acwopencirclearrow \adots \ae \aleph \alpha \angle \approx \approxeq \approxident \arceq \ast \asymp \backcong \backprime \backsim \backsimeq \backslash \bar \barleftarrow \barwedge \because \beta \beth \between \bigcap \bigcirc \bigcup \bigodot \bigoplus \bigotimes \bigstar \bigtriangledown \bigtriangleup \biguplus \bigvee \bigwedge \blacksquare \blacktriangle \blacktriangledown \blacktriangleleft \blacktriangleright \bot \bowtie \boxbar \boxdot \boxminus \boxplus \boxtimes \breve \bullet \bumpeq \c \candra \cap \carriagereturn \cdot \cdotp \cdots \check \checkmark \chi \circ \circeq \circledR \circledS \circledast \circledcirc \circleddash \circumflexaccent \clubsuit \clubsuitopen \colon \coloneq \combiningacuteaccent \combiningbreve \combiningdiaeresis \combiningdotabove \combininggraveaccent \combiningoverline \combiningrightarrowabove \combiningtilde \complement \cong \coprod \copyright \cup \cupdot \curlyeqprec \curlyeqsucc \curlyvee \curlywedge \curvearrowleft \curvearrowright \cwopencirclearrow \d \dag \daleth \danger \dashv \ddag \ddddot \dddot \ddot \ddots \degree \delta \diamond \diamondsuit \digamma \div \divideontimes \dot \doteq \dotminus \dotplus \dots \doublebarwedge ? \downarrow \downdownarrows \downharpoonleft \downharpoonright \downzigzagarrow \ell \emdash \emptyset \endash \enspace \epsilon \eqcirc \eqcolon \eqdef \eqgtr \eqless \eqsim \equiv \eta \eth \exists \fallingdotseq \flat \forall \frakC \frakZ \frown \gamma \geq \geqq \gg \ggg \gimel \gneqq \gnsim \grave \greater \gtrdot \gtreqless \gtrless \gtrsim \hat \heartsuit \hookleftarrow \hookrightarrow \i \iiint \iint \imageof \imath \in \infty \int \intercal \invnot \iota \jmath \k \kappa \kernelcontraction \l \lambda \lambdabar \lasp \lbrace \lbrack \lceil \leftangle \leftarrow \leftarrowtail \leftbrace \leftharpoonaccent \leftharpoondown \leftharpoonup \leftleftarrows \leftparen \leftrightarrow \leftrightarrows \leftrightharpoons \leftthreetimes \leq \leqq \less \lessdot \lesseqgtr \lessgtr \lesssim \lfloor \ll \llcorner \lll \lneqq \lnsim \looparrowleft \looparrowright \lq \lrcorner \ltimes \maltese \mapsdown \mapsfrom \mapsto \mapsup \measeq \measuredangle \mho \mid \minus \models \mp \mu \multimap \nLeftarrow \nLeftrightarrow \nRightarrow \nVDash \nVdash \nabla \napprox \natural \ncong \ne \nearrow \neg \nequiv \nexists \ngeq \ngtr \ni \nleftarrow \nleftrightarrow \nleq \nless \nmid \not \notin \nparallel \nprec \nrightarrow \nsim \nsime \nsubset \nsubseteq \nsucc \nsupset \nsupseteq \ntriangleleft \ntrianglelefteq \ntriangleright \ntrianglerighteq \nu \nvDash \nvdash \nwarrow \o \obar \ocirc \odot \oe \oiiint \oiint \oint \omega \ominus \oplus \origof \oslash \otimes \overarc \overleftarrow \overleftrightarrow \parallel \partial \phi \pi \pitchfork \pm \prec \preccurlyeq \preceq \precnsim \precsim \prime \prod \propto \prurel \psi \quad \questeq \rasp \rbrace \rbrack \rceil \rfloor \rho \rightangle \rightarrow \rightarrowbar \rightarrowtail \rightbrace \rightharpoonaccent \rightharpoondown \rightharpoonup \rightleftarrows \rightleftharpoons \rightparen \rightrightarrows \rightthreetimes \rightzigzagarrow \risingdotseq \rq \rtimes \scrB \scrE \scrF \scrH \scrI \scrL \scrM \scrR \scre \scrg \scro \scurel \searrow \sharp \sigma \sim \simeq \slash \smallsetminus \smile \solbar \spadesuit \spadesuitopen \sphericalangle \sqcap \sqcup \sqsubset \sqsubseteq \sqsupset \sqsupseteq \ss \star \stareq \sterling \subset \subseteq \subsetneq \succ \succcurlyeq \succeq \succnsim \succsim \sum \supset \supseteq \supsetneq \swarrow \t \tau \textasciiacute \textasciicircum \textasciigrave \textasciitilde \textexclamdown \textquestiondown \textquotedblleft \textquotedblright \therefore \theta \thickspace \thinspace \tilde \times \to \top \triangledown \triangleleft \trianglelefteq \triangleq \triangleright \trianglerighteq \turnednot \twoheaddownarrow \twoheadleftarrow \twoheadrightarrow \twoheaduparrow \ulcorner \underbar \uparrow \updownarrow \updownarrowbar \updownarrows \upharpoonleft \upharpoonright \uplus \upsilon \upuparrows \urcorner \vDash \varepsilon \varkappa \varnothing \varphi \varpi \varrho \varsigma \vartheta \vartriangle \vartriangleleft \vartriangleright \vdash \vdots \vec \vee \veebar \veeeq \vert \wedge \wedgeq \widehat \widetilde \wp \wr \xi \yen \zeta \{ \| \} BACKENDS mathtext currently works with all backends. KNOWN ISSUES: - Certainly there are some... Author : John Hunter <jdhunter@ace.bsd.uchicago.edu> Michael Droettboom <mdroe@stsci.edu> (rewrite based on TeX box layout algorithms) Copyright : John Hunter (2004,2005) License : matplotlib license (PSF compatible) """ from __future__ import division import os from cStringIO import StringIO from math import ceil from sets import Set import unicodedata from warnings import warn from numpy import inf, isinf import numpy as np from matplotlib.pyparsing import Combine, Group, Optional, Forward, \ Literal, OneOrMore, ZeroOrMore, ParseException, Empty, \ ParseResults, Suppress, oneOf, StringEnd, ParseFatalException, \ FollowedBy, Regex, ParserElement # Enable packrat parsing ParserElement.enablePackrat() from matplotlib.afm import AFM from matplotlib.cbook import Bunch, get_realpath_and_stat, \ is_string_like, maxdict from matplotlib.ft2font import FT2Font, FT2Image, KERNING_DEFAULT, LOAD_FORCE_AUTOHINT, LOAD_NO_HINTING from matplotlib.font_manager import findfont, FontProperties from matplotlib._mathtext_data import latex_to_bakoma, \ latex_to_standard, tex2uni, latex_to_cmex, stix_virtual_fonts from matplotlib import get_data_path, rcParams import matplotlib.colors as mcolors import matplotlib._png as _png #################### ############################################################################## # FONTS def get_unicode_index(symbol): """get_unicode_index(symbol) -> integer Return the integer index (from the Unicode table) of symbol. symbol can be a single unicode character, a TeX command (i.e. r'\pi'), or a Type1 symbol name (i.e. 'phi'). """ # From UTF #25: U+2212 minus sign is the preferred # representation of the unary and binary minus sign rather than # the ASCII-derived U+002D hyphen-minus, because minus sign is # unambiguous and because it is rendered with a more desirable # length, usually longer than a hyphen. if symbol == '-': return 0x2212 try:# This will succeed if symbol is a single unicode char return ord(symbol) except TypeError: pass try:# Is symbol a TeX symbol (i.e. \alpha) return tex2uni[symbol.strip("\\")] except KeyError: message = """'%(symbol)s' is not a valid Unicode character or TeX/Type1 symbol"""%locals() raise ValueError, message class MathtextBackend(object): def __init__(self): self.fonts_object = None def set_canvas_size(self, w, h, d): 'Dimension the drawing canvas; may be a noop' self.width = w self.height = h self.depth = d def render_glyph(self, ox, oy, info): raise NotImplementedError() def render_filled_rect(self, x1, y1, x2, y2): raise NotImplementedError() def get_results(self, box): """Return a backend specific tuple of things to return to the backend after all processing is done.""" raise NotImplementedError() def get_hinting_type(self): return LOAD_NO_HINTING 00262 class MathtextBackendBbox(MathtextBackend): """A backend whose only purpose is to get a precise bounding box. Only required for the Agg backend.""" def __init__(self, real_backend): MathtextBackend.__init__(self) self.bbox = [0, 0, 0, 0] self.real_backend = real_backend def _update_bbox(self, x1, y1, x2, y2): self.bbox = [min(self.bbox[0], x1), min(self.bbox[1], y1), max(self.bbox[2], x2), max(self.bbox[3], y2)] def render_glyph(self, ox, oy, info): self._update_bbox(ox + info.metrics.xmin, oy - info.metrics.ymax, ox + info.metrics.xmax, oy - info.metrics.ymin) def render_rect_filled(self, x1, y1, x2, y2): self._update_bbox(x1, y1, x2, y2) def get_results(self, box): orig_height = box.height orig_depth = box.depth ship(0, 0, box) bbox = self.bbox bbox = [bbox[0] - 1, bbox[1] - 1, bbox[2] + 1, bbox[3] + 1] self._switch_to_real_backend() self.fonts_object.set_canvas_size( bbox[2] - bbox[0], (bbox[3] - bbox[1]) - orig_depth, (bbox[3] - bbox[1]) - orig_height) ship(-bbox[0], -bbox[1], box) return self.fonts_object.get_results(box) def get_hinting_type(self): return self.real_backend.get_hinting_type() def _switch_to_real_backend(self): self.fonts_object.mathtext_backend = self.real_backend self.real_backend.fonts_object = self.fonts_object self.real_backend.ox = self.bbox[0] self.real_backend.oy = self.bbox[1] class MathtextBackendAggRender(MathtextBackend): def __init__(self): self.ox = 0 self.oy = 0 self.image = None MathtextBackend.__init__(self) def set_canvas_size(self, w, h, d): MathtextBackend.set_canvas_size(self, w, h, d) self.image = FT2Image(ceil(w), ceil(h + d)) def render_glyph(self, ox, oy, info): info.font.draw_glyph_to_bitmap( self.image, ox, oy - info.metrics.ymax, info.glyph) def render_rect_filled(self, x1, y1, x2, y2): self.image.draw_rect_filled(x1, y1, x2, max(y2 - 1, y1)) def get_results(self, box): return (self.ox, self.oy, self.width, self.height + self.depth, self.depth, self.image, self.fonts_object.get_used_characters()) def get_hinting_type(self): return LOAD_FORCE_AUTOHINT def MathtextBackendAgg(): return MathtextBackendBbox(MathtextBackendAggRender()) class MathtextBackendBitmapRender(MathtextBackendAggRender): def get_results(self, box): return self.image, self.depth def MathtextBackendBitmap(): return MathtextBackendBbox(MathtextBackendBitmapRender()) class MathtextBackendPs(MathtextBackend): def __init__(self): self.pswriter = StringIO() self.lastfont = None def render_glyph(self, ox, oy, info): oy = self.height - oy + info.offset postscript_name = info.postscript_name fontsize = info.fontsize symbol_name = info.symbol_name if (postscript_name, fontsize) != self.lastfont: ps = """/%(postscript_name)s findfont %(fontsize)s scalefont setfont """ % locals() self.lastfont = postscript_name, fontsize self.pswriter.write(ps) ps = """%(ox)f %(oy)f moveto /%(symbol_name)s glyphshow\n """ % locals() self.pswriter.write(ps) def render_rect_filled(self, x1, y1, x2, y2): ps = "%f %f %f %f rectfill\n" % (x1, self.height - y2, x2 - x1, y2 - y1) self.pswriter.write(ps) def get_results(self, box): ship(0, -self.depth, box) #print self.depth return (self.width, self.height + self.depth, self.depth, self.pswriter, self.fonts_object.get_used_characters()) class MathtextBackendPdf(MathtextBackend): def __init__(self): self.glyphs = [] self.rects = [] def render_glyph(self, ox, oy, info): filename = info.font.fname oy = self.height - oy + info.offset self.glyphs.append( (ox, oy, filename, info.fontsize, info.num, info.symbol_name)) def render_rect_filled(self, x1, y1, x2, y2): self.rects.append((x1, self.height - y2, x2 - x1, y2 - y1)) def get_results(self, box): ship(0, -self.depth, box) return (self.width, self.height + self.depth, self.depth, self.glyphs, self.rects, self.fonts_object.get_used_characters()) class MathtextBackendSvg(MathtextBackend): def __init__(self): self.svg_glyphs = [] self.svg_rects = [] def render_glyph(self, ox, oy, info): oy = self.height - oy + info.offset thetext = unichr(info.num) self.svg_glyphs.append( (info.font, info.fontsize, thetext, ox, oy, info.metrics)) def render_rect_filled(self, x1, y1, x2, y2): self.svg_rects.append( (x1, self.height - y1 + 1, x2 - x1, y2 - y1)) def get_results(self, box): ship(0, -self.depth, box) svg_elements = Bunch(svg_glyphs = self.svg_glyphs, svg_rects = self.svg_rects) return (self.width, self.height + self.depth, self.depth, svg_elements, self.fonts_object.get_used_characters()) class MathtextBackendCairo(MathtextBackend): def __init__(self): self.glyphs = [] self.rects = [] def render_glyph(self, ox, oy, info): oy = oy - info.offset - self.height thetext = unichr(info.num) self.glyphs.append( (info.font, info.fontsize, thetext, ox, oy)) def render_rect_filled(self, x1, y1, x2, y2): self.rects.append( (x1, y1 - self.height, x2 - x1, y2 - y1)) def get_results(self, box): ship(0, -self.depth, box) return (self.width, self.height + self.depth, self.depth, self.glyphs, self.rects) 00458 class Fonts(object): """ An abstract base class for fonts that want to render mathtext The class must be able to take symbol keys and font file names and return the character metrics. It also delegates to a backend class to do the actual drawing. """ 00467 def __init__(self, default_font_prop, mathtext_backend): """default_font_prop: A FontProperties object to use for the default non-math font, or the base font for Unicode font rendering. mathtext_backend: A subclass of MathTextBackend used to delegate the actual rendering.""" self.default_font_prop = default_font_prop self.mathtext_backend = mathtext_backend # Make these classes doubly-linked self.mathtext_backend.fonts_object = self self.used_characters = {} 00479 def destroy(self): """Fix any cyclical references before the object is about to be destroyed.""" self.used_characters = None 00484 def get_kern(self, font1, sym1, fontsize1, font2, sym2, fontsize2, dpi): """ Get the kerning distance for font between sym1 and sym2. fontX: one of the TeX font names, tt, it, rm, cal, sf, bf or default (non-math) symX: a symbol in raw TeX form. e.g. '1', 'x' or '\sigma' fontsizeX: the fontsize in points dpi: the current dots-per-inch sym is a single symbol(alphanum, punct) or a special symbol like \sigma. """ return 0. 00501 def get_metrics(self, font, font_class, sym, fontsize, dpi): """ font: one of the TeX font names, tt, it, rm, cal, sf, bf or default (non-math) sym: a symbol in raw TeX form. e.g. '1', 'x' or '\sigma' fontsize: font size in points dpi: current dots-per-inch advance height width xmin, xmax, ymin, ymax - the ink rectangle of the glyph iceberg - the distance from the baseline to the top of the glyph. horiBearingY in Truetype parlance, height in TeX parlance """ info = self._get_info(font, font_class, sym, fontsize, dpi) return info.metrics def set_canvas_size(self, w, h, d): 'Dimension the drawing canvas; may be a noop' self.width, self.height, self.depth = ceil(w), ceil(h), ceil(d) self.mathtext_backend.set_canvas_size(self.width, self.height, self.depth) def render_glyph(self, ox, oy, facename, font_class, sym, fontsize, dpi): info = self._get_info(facename, font_class, sym, fontsize, dpi) realpath, stat_key = get_realpath_and_stat(info.font.fname) used_characters = self.used_characters.setdefault( stat_key, (realpath, Set())) used_characters[1].add(info.num) self.mathtext_backend.render_glyph(ox, oy, info) def render_rect_filled(self, x1, y1, x2, y2): self.mathtext_backend.render_rect_filled(x1, y1, x2, y2) def get_xheight(self, font, fontsize, dpi): raise NotImplementedError() def get_underline_thickness(self, font, fontsize, dpi): raise NotImplementedError() def get_used_characters(self): return self.used_characters def get_results(self, box): return self.mathtext_backend.get_results(box) 00547 def get_sized_alternatives_for_symbol(self, fontname, sym): """ Override if your font provides multiple sizes of the same symbol. """ return [(fontname, sym)] 00554 class TruetypeFonts(Fonts): """ A generic base class for all font setups that use Truetype fonts (through ft2font) """ _fonts = {} class CachedFont: def __init__(self, font): self.font = font self.charmap = font.get_charmap() self.glyphmap = dict( [(glyphind, ccode) for ccode, glyphind in self.charmap.iteritems()]) def __repr__(self): return repr(self.font) 00571 def __init__(self, default_font_prop, mathtext_backend): Fonts.__init__(self, default_font_prop, mathtext_backend) self.glyphd = {} if self._fonts == {}: filename = findfont(default_font_prop) default_font = self.CachedFont(FT2Font(str(filename))) self._fonts['default'] = default_font def destroy(self): self.glyphd = None Fonts.destroy(self) def _get_font(self, font): """Looks up a CachedFont with its charmap and inverse charmap. font may be a TeX font name (cal, rm, it etc.), or postscript name.""" if font in self.fontmap: basename = self.fontmap[font] else: basename = font cached_font = self._fonts.get(basename) if cached_font is None: font = FT2Font(basename) cached_font = self.CachedFont(font) self._fonts[basename] = cached_font self._fonts[font.postscript_name] = cached_font self._fonts[font.postscript_name.lower()] = cached_font return cached_font def _get_offset(self, cached_font, glyph, fontsize, dpi): if cached_font.font.postscript_name == 'Cmex10': return glyph.height/64.0/2.0 + 256.0/64.0 * dpi/72.0 return 0. def _get_info(self, fontname, font_class, sym, fontsize, dpi): 'load the cmfont, metrics and glyph with caching' key = fontname, font_class, sym, fontsize, dpi bunch = self.glyphd.get(key) if bunch is not None: return bunch cached_font, num, symbol_name, fontsize, slanted = \ self._get_glyph(fontname, font_class, sym, fontsize) font = cached_font.font font.set_size(fontsize, dpi) glyph = font.load_char( num, flags=self.mathtext_backend.get_hinting_type()) xmin, ymin, xmax, ymax = [val/64.0 for val in glyph.bbox] offset = self._get_offset(cached_font, glyph, fontsize, dpi) metrics = Bunch( advance = glyph.linearHoriAdvance/65536.0, height = glyph.height/64.0, width = glyph.width/64.0, xmin = xmin, xmax = xmax, ymin = ymin+offset, ymax = ymax+offset, # iceberg is the equivalent of TeX's "height" iceberg = glyph.horiBearingY/64.0 + offset, slanted = slanted ) result = self.glyphd[key] = Bunch( font = font, fontsize = fontsize, postscript_name = font.postscript_name, metrics = metrics, symbol_name = symbol_name, num = num, glyph = glyph, offset = offset ) return result def get_xheight(self, font, fontsize, dpi): cached_font = self._get_font(font) cached_font.font.set_size(fontsize, dpi) pclt = cached_font.font.get_sfnt_table('pclt') if pclt is None: # Some fonts don't store the xHeight, so we do a poor man's xHeight metrics = self.get_metrics(font, 'it', 'x', fontsize, dpi) return metrics.iceberg xHeight = (pclt['xHeight'] / 64.0) * (fontsize / 12.0) * (dpi / 100.0) return xHeight def get_underline_thickness(self, font, fontsize, dpi): # This function used to grab underline thickness from the font, # but that information is just too un-reliable, so it is now hardcoded. return ((0.75 / 12.0) * fontsize * dpi) / 72.0 def get_kern(self, font1, fontclass1, sym1, fontsize1, font2, fontclass2, sym2, fontsize2, dpi): if font1 == font2 and fontsize1 == fontsize2: info1 = self._get_info(font1, fontclass1, sym1, fontsize1, dpi) info2 = self._get_info(font2, fontclass2, sym2, fontsize2, dpi) font = info1.font return font.get_kerning(info1.num, info2.num, KERNING_DEFAULT) / 64.0 return 0.0 00675 class BakomaFonts(TruetypeFonts): """ Use the Bakoma true type fonts for rendering """ _fontmap = { 'cal' : 'cmsy10', 'rm' : 'cmr10', 'tt' : 'cmtt10', 'it' : 'cmmi10', 'bf' : 'cmb10', 'sf' : 'cmss10', 'ex' : 'cmex10' } fontmap = {} 00689 def __init__(self, *args, **kwargs): self._stix_fallback = StixFonts(*args, **kwargs) TruetypeFonts.__init__(self, *args, **kwargs) if not len(self.fontmap): for key, val in self._fontmap.iteritems(): fullpath = findfont(val) self.fontmap[key] = fullpath self.fontmap[val] = fullpath _slanted_symbols = Set(r"\int \oint".split()) def _get_glyph(self, fontname, font_class, sym, fontsize): symbol_name = None if fontname in self.fontmap and latex_to_bakoma.has_key(sym): basename, num = latex_to_bakoma[sym] slanted = (basename == "cmmi10") or sym in self._slanted_symbols try: cached_font = self._get_font(basename) except RuntimeError: pass else: symbol_name = cached_font.font.get_glyph_name(num) num = cached_font.glyphmap[num] elif len(sym) == 1: slanted = (fontname == "it") try: cached_font = self._get_font(fontname) except RuntimeError: pass else: num = ord(sym) gid = cached_font.charmap.get(num) if gid is not None: symbol_name = cached_font.font.get_glyph_name( cached_font.charmap[num]) if symbol_name is None: return self._stix_fallback._get_glyph( fontname, font_class, sym, fontsize) return cached_font, num, symbol_name, fontsize, slanted # The Bakoma fonts contain many pre-sized alternatives for the # delimiters. The AutoSizedChar class will use these alternatives # and select the best (closest sized) glyph. _size_alternatives = { '(' : [('rm', '('), ('ex', '\xa1'), ('ex', '\xb3'), ('ex', '\xb5'), ('ex', '\xc3')], ')' : [('rm', ')'), ('ex', '\xa2'), ('ex', '\xb4'), ('ex', '\xb6'), ('ex', '\x21')], '{' : [('cal', '{'), ('ex', '\xa9'), ('ex', '\x6e'), ('ex', '\xbd'), ('ex', '\x28')], '}' : [('cal', '}'), ('ex', '\xaa'), ('ex', '\x6f'), ('ex', '\xbe'), ('ex', '\x29')], # The fourth size of '[' is mysteriously missing from the BaKoMa # font, so I've ommitted it for both '[' and ']' '[' : [('rm', '['), ('ex', '\xa3'), ('ex', '\x68'), ('ex', '\x22')], ']' : [('rm', ']'), ('ex', '\xa4'), ('ex', '\x69'), ('ex', '\x23')], r'\lfloor' : [('ex', '\xa5'), ('ex', '\x6a'), ('ex', '\xb9'), ('ex', '\x24')], r'\rfloor' : [('ex', '\xa6'), ('ex', '\x6b'), ('ex', '\xba'), ('ex', '\x25')], r'\lceil' : [('ex', '\xa7'), ('ex', '\x6c'), ('ex', '\xbb'), ('ex', '\x26')], r'\rceil' : [('ex', '\xa8'), ('ex', '\x6d'), ('ex', '\xbc'), ('ex', '\x27')], r'\langle' : [('ex', '\xad'), ('ex', '\x44'), ('ex', '\xbf'), ('ex', '\x2a')], r'\rangle' : [('ex', '\xae'), ('ex', '\x45'), ('ex', '\xc0'), ('ex', '\x2b')], r'\__sqrt__' : [('ex', '\x70'), ('ex', '\x71'), ('ex', '\x72'), ('ex', '\x73')], r'\backslash': [('ex', '\xb2'), ('ex', '\x2f'), ('ex', '\xc2'), ('ex', '\x2d')], r'/' : [('rm', '/'), ('ex', '\xb1'), ('ex', '\x2e'), ('ex', '\xcb'), ('ex', '\x2c')], r'\widehat' : [('rm', '\x5e'), ('ex', '\x62'), ('ex', '\x63'), ('ex', '\x64')], r'\widetilde': [('rm', '\x7e'), ('ex', '\x65'), ('ex', '\x66'), ('ex', '\x67')] } for alias, target in [('\leftparen', '('), ('\rightparent', ')'), ('\leftbrace', '{'), ('\rightbrace', '}'), ('\leftbracket', '['), ('\rightbracket', ']')]: _size_alternatives[alias] = _size_alternatives[target] 00783 def get_sized_alternatives_for_symbol(self, fontname, sym): alternatives = self._size_alternatives.get(sym) if alternatives: return alternatives return [(fontname, sym)] 00789 class UnicodeFonts(TruetypeFonts): """An abstract base class for handling Unicode fonts. """ fontmap = {} use_cmex = True 00796 def __init__(self, *args, **kwargs): # This must come first so the backend's owner is set correctly if rcParams['mathtext.fallback_to_cm']: self.cm_fallback = BakomaFonts(*args, **kwargs) else: self.cm_fallback = None TruetypeFonts.__init__(self, *args, **kwargs) if not len(self.fontmap): for texfont in "cal rm tt it bf sf".split(): prop = rcParams['mathtext.' + texfont] font = findfont(prop) self.fontmap[texfont] = font prop = FontProperties('cmex10') font = findfont(prop) self.fontmap['ex'] = font _slanted_symbols = Set(r"\int \oint".split()) def _map_virtual_font(self, fontname, font_class, uniindex): return fontname, uniindex def _get_glyph(self, fontname, font_class, sym, fontsize): found_symbol = False if self.use_cmex: uniindex = latex_to_cmex.get(sym) if uniindex is not None: fontname = 'ex' found_symbol = True if not found_symbol: try: uniindex = get_unicode_index(sym) found_symbol = True except ValueError: uniindex = ord('?') warn("No TeX to unicode mapping for '%s'" % sym.encode('ascii', 'backslashreplace'), MathTextWarning) fontname, uniindex = self._map_virtual_font( fontname, font_class, uniindex) # Only characters in the "Letter" class should be italicized in 'it' # mode. Greek capital letters should be Roman. if found_symbol: new_fontname = fontname if fontname == 'it': if uniindex < 0x10000: unistring = unichr(uniindex) if (not unicodedata.category(unistring)[0] == "L" or unicodedata.name(unistring).startswith("GREEK CAPITAL")): new_fontname = 'rm' slanted = (new_fontname == 'it') or sym in self._slanted_symbols found_symbol = False try: cached_font = self._get_font(new_fontname) except RuntimeError: pass else: try: glyphindex = cached_font.charmap[uniindex] found_symbol = True except KeyError: pass if not found_symbol: if self.cm_fallback: warn("Substituting with a symbol from Computer Modern.", MathTextWarning) return self.cm_fallback._get_glyph( fontname, 'it', sym, fontsize) else: if fontname == 'it' and isinstance(self, StixFonts): return self._get_glyph('rm', font_class, sym, fontsize) warn("Font '%s' does not have a glyph for '%s'" % (cached_font.font.postscript_name, sym.encode('ascii', 'backslashreplace')), MathTextWarning) warn("Substituting with a dummy symbol.", MathTextWarning) fontname = 'rm' new_fontname = fontname cached_font = self._get_font(fontname) uniindex = 0xA4 # currency character, for lack of anything better glyphindex = cached_font.charmap[uniindex] slanted = False symbol_name = cached_font.font.get_glyph_name(glyphindex) return cached_font, uniindex, symbol_name, fontsize, slanted 00888 def get_sized_alternatives_for_symbol(self, fontname, sym): if self.cm_fallback: return self.cm_fallback.get_sized_alternatives_for_symbol( fontname, sym) return [(fontname, sym)] 00894 class StixFonts(UnicodeFonts): """ A font handling class for the STIX fonts """ _fontmap = { 'rm' : 'STIXGeneral', 'it' : 'STIXGeneral:italic', 'bf' : 'STIXGeneral:weight=bold', 'nonunirm' : 'STIXNonUnicode', 'nonuniit' : 'STIXNonUnicode:italic', 'nonunibf' : 'STIXNonUnicode:weight=bold', 0 : 'STIXGeneral', 1 : 'STIXSize1', 2 : 'STIXSize2', 3 : 'STIXSize3', 4 : 'STIXSize4', 5 : 'STIXSize5' } fontmap = {} use_cmex = False cm_fallback = False _sans = False 00917 def __init__(self, *args, **kwargs): TruetypeFonts.__init__(self, *args, **kwargs) if not len(self.fontmap): for key, name in self._fontmap.iteritems(): fullpath = findfont(name) self.fontmap[key] = fullpath self.fontmap[name] = fullpath def _map_virtual_font(self, fontname, font_class, uniindex): # Handle these "fonts" that are actually embedded in # other fonts. mapping = stix_virtual_fonts.get(fontname) if self._sans and mapping is None: mapping = stix_virtual_fonts['sf'] doing_sans_conversion = True else: doing_sans_conversion = False if mapping is not None: if isinstance(mapping, dict): mapping = mapping[font_class] # Binary search for the source glyph lo = 0 hi = len(mapping) while lo < hi: mid = (lo+hi)//2 range = mapping[mid] if uniindex < range[0]: hi = mid elif uniindex <= range[1]: break else: lo = mid + 1 if uniindex >= range[0] and uniindex <= range[1]: uniindex = uniindex - range[0] + range[3] fontname = range[2] elif not doing_sans_conversion: # This will generate a dummy character uniindex = 0x1 fontname = 'it' # Handle private use area glyphs if (fontname in ('it', 'rm', 'bf') and uniindex >= 0xe000 and uniindex <= 0xf8ff): fontname = 'nonuni' + fontname return fontname, uniindex _size_alternatives = {} 00968 def get_sized_alternatives_for_symbol(self, fontname, sym): alternatives = self._size_alternatives.get(sym) if alternatives: return alternatives alternatives = [] try: uniindex = get_unicode_index(sym) except ValueError: return [(fontname, sym)] for i in range(6): cached_font = self._get_font(i) glyphindex = cached_font.charmap.get(uniindex) if glyphindex is not None: alternatives.append((i, unichr(uniindex))) self._size_alternatives[sym] = alternatives return alternatives 00988 class StixSansFonts(StixFonts): """ A font handling class for the STIX fonts (using sans-serif characters by default). """ _sans = True 00995 class StandardPsFonts(Fonts): """ Use the standard postscript fonts for rendering to backend_ps Unlike the other font classes, BakomaFont and UnicodeFont, this one requires the Ps backend. """ basepath = os.path.join( get_data_path(), 'fonts', 'afm' ) fontmap = { 'cal' : 'pzcmi8a', # Zapf Chancery 'rm' : 'pncr8a', # New Century Schoolbook 'tt' : 'pcrr8a', # Courier 'it' : 'pncri8a', # New Century Schoolbook Italic 'sf' : 'phvr8a', # Helvetica 'bf' : 'pncb8a', # New Century Schoolbook Bold None : 'psyr' # Symbol } def __init__(self, default_font_prop): Fonts.__init__(self, default_font_prop, MathtextBackendPs()) self.glyphd = {} self.fonts = {} filename = findfont(default_font_prop, fontext='afm') default_font = AFM(file(filename, 'r')) default_font.fname = filename self.fonts['default'] = default_font self.pswriter = StringIO() def _get_font(self, font): if font in self.fontmap: basename = self.fontmap[font] else: basename = font cached_font = self.fonts.get(basename) if cached_font is None: fname = os.path.join(self.basepath, basename + ".afm") cached_font = AFM(file(fname, 'r')) cached_font.fname = fname self.fonts[basename] = cached_font self.fonts[cached_font.get_fontname()] = cached_font return cached_font def _get_info (self, fontname, font_class, sym, fontsize, dpi): 'load the cmfont, metrics and glyph with caching' key = fontname, sym, fontsize, dpi tup = self.glyphd.get(key) if tup is not None: return tup # Only characters in the "Letter" class should really be italicized. # This class includes greek letters, so we're ok if (fontname == 'it' and (len(sym) > 1 or not unicodedata.category(unicode(sym)).startswith("L"))): fontname = 'rm' found_symbol = False if latex_to_standard.has_key(sym): fontname, num = latex_to_standard[sym] glyph = chr(num) found_symbol = True elif len(sym) == 1: glyph = sym num = ord(glyph) found_symbol = True else: warn("No TeX to built-in Postscript mapping for '%s'" % sym, MathTextWarning) slanted = (fontname == 'it') font = self._get_font(fontname) if found_symbol: try: symbol_name = font.get_name_char(glyph) except KeyError: warn("No glyph in standard Postscript font '%s' for '%s'" % (font.postscript_name, sym), MathTextWarning) found_symbol = False if not found_symbol: glyph = sym = '?' num = ord(glyph) symbol_name = font.get_name_char(glyph) offset = 0 scale = 0.001 * fontsize xmin, ymin, xmax, ymax = [val * scale for val in font.get_bbox_char(glyph)] metrics = Bunch( advance = font.get_width_char(glyph) * scale, width = font.get_width_char(glyph) * scale, height = font.get_height_char(glyph) * scale, xmin = xmin, xmax = xmax, ymin = ymin+offset, ymax = ymax+offset, # iceberg is the equivalent of TeX's "height" iceberg = ymax + offset, slanted = slanted ) self.glyphd[key] = Bunch( font = font, fontsize = fontsize, postscript_name = font.get_fontname(), metrics = metrics, symbol_name = symbol_name, num = num, glyph = glyph, offset = offset ) return self.glyphd[key] def get_kern(self, font1, fontclass1, sym1, fontsize1, font2, fontclass2, sym2, fontsize2, dpi): if font1 == font2 and fontsize1 == fontsize2: info1 = self._get_info(font1, fontclass1, sym1, fontsize1, dpi) info2 = self._get_info(font2, fontclass2, sym2, fontsize2, dpi) font = info1.font return (font.get_kern_dist(info1.glyph, info2.glyph) * 0.001 * fontsize1) return 0.0 def get_xheight(self, font, fontsize, dpi): cached_font = self._get_font(font) return cached_font.get_xheight() * 0.001 * fontsize def get_underline_thickness(self, font, fontsize, dpi): cached_font = self._get_font(font) return cached_font.get_underline_thickness() * 0.001 * fontsize ############################################################################## # TeX-LIKE BOX MODEL # The following is based directly on the document 'woven' from the # TeX82 source code. This information is also available in printed # form: # # Knuth, Donald E.. 1986. Computers and Typesetting, Volume B: # TeX: The Program. Addison-Wesley Professional. # # The most relevant "chapters" are: # Data structures for boxes and their friends # Shipping pages out (Ship class) # Packaging (hpack and vpack) # Data structures for math mode # Subroutines for math mode # Typesetting math formulas # # Many of the docstrings below refer to a numbered "node" in that # book, e.g. node123 # # Note that (as TeX) y increases downward, unlike many other parts of # matplotlib. # How much text shrinks when going to the next-smallest level. GROW_FACTOR # must be the inverse of SHRINK_FACTOR. SHRINK_FACTOR = 0.7 GROW_FACTOR = 1.0 / SHRINK_FACTOR # The number of different sizes of chars to use, beyond which they will not # get any smaller NUM_SIZE_LEVELS = 4 # Percentage of x-height of additional horiz. space after sub/superscripts SCRIPT_SPACE = 0.2 # Percentage of x-height that sub/superscripts drop below the baseline SUBDROP = 0.3 # Percentage of x-height that superscripts drop below the baseline SUP1 = 0.7 # Percentage of x-height that subscripts drop below the baseline SUB1 = 0.0 # Percentage of x-height that superscripts are offset relative to the subscript DELTA = 0.18 class MathTextWarning(Warning): pass 01181 class Node(object): """A node in the TeX box model node133 """ def __init__(self): self.size = 0 def __repr__(self): return self.__internal_repr__() def __internal_repr__(self): return self.__class__.__name__ def get_kerning(self, next): return 0.0 01197 def shrink(self): """Shrinks one level smaller. There are only three levels of sizes, after which things will no longer get smaller.""" self.size += 1 01202 def grow(self): """Grows one level larger. There is no limit to how big something can get.""" self.size -= 1 def render(self, x, y): pass 01210 class Box(Node): """Represents any node with a physical location. node135""" def __init__(self, width, height, depth): Node.__init__(self) self.width = width self.height = height self.depth = depth 01219 def shrink(self): Node.shrink(self) if self.size < NUM_SIZE_LEVELS: self.width *= SHRINK_FACTOR self.height *= SHRINK_FACTOR self.depth *= SHRINK_FACTOR 01226 def grow(self): Node.grow(self) self.width *= GROW_FACTOR self.height *= GROW_FACTOR self.depth *= GROW_FACTOR def render(self, x1, y1, x2, y2): pass 01235 class Vbox(Box): """ A box with only height (zero width). """ def __init__(self, height, depth): Box.__init__(self, 0., height, depth) 01242 class Hbox(Box): """ A box with only width (zero height and depth). """ def __init__(self, width): Box.__init__(self, width, 0., 0.) 01249 class Char(Node): """Represents a single character. Unlike TeX, the font information and metrics are stored with each Char to make it easier to lookup the font metrics when needed. Note that TeX boxes have a width, height, and depth, unlike Type1 and Truetype which use a full bounding box and an advance in the x-direction. The metrics must be converted to the TeX way, and the advance (if different from width) must be converted into a Kern node when the Char is added to its parent Hlist. node134""" def __init__(self, c, state): Node.__init__(self) self.c = c self.font_output = state.font_output assert isinstance(state.font, (str, unicode, int)) self.font = state.font self.font_class = state.font_class self.fontsize = state.fontsize self.dpi = state.dpi # The real width, height and depth will be set during the # pack phase, after we know the real fontsize self._update_metrics() def __internal_repr__(self): return '`%s`' % self.c def _update_metrics(self): metrics = self._metrics = self.font_output.get_metrics( self.font, self.font_class, self.c, self.fontsize, self.dpi) if self.c == ' ': self.width = metrics.advance else: self.width = metrics.width self.height = metrics.iceberg self.depth = -(metrics.iceberg - metrics.height) def is_slanted(self): return self._metrics.slanted 01288 def get_kerning(self, next): """Return the amount of kerning between this and the given character. Called when characters are strung together into Hlists to create Kern nodes.""" advance = self._metrics.advance - self.width kern = 0. if isinstance(next, Char): kern = self.font_output.get_kern( self.font, self.font_class, self.c, self.fontsize, next.font, next.font_class, next.c, next.fontsize, self.dpi) return advance + kern 01301 def render(self, x, y): """Render the character to the canvas""" self.font_output.render_glyph( x, y, self.font, self.font_class, self.c, self.fontsize, self.dpi) 01307 def shrink(self): Node.shrink(self) if self.size < NUM_SIZE_LEVELS: self.fontsize *= SHRINK_FACTOR self.width *= SHRINK_FACTOR self.height *= SHRINK_FACTOR self.depth *= SHRINK_FACTOR 01315 def grow(self): Node.grow(self) self.fontsize *= GROW_FACTOR self.width *= GROW_FACTOR self.height *= GROW_FACTOR self.depth *= GROW_FACTOR 01322 class Accent(Char): """The font metrics need to be dealt with differently for accents, since they are already offset correctly from the baseline in TrueType fonts.""" def _update_metrics(self): metrics = self._metrics = self.font_output.get_metrics( self.font, self.font_class, self.c, self.fontsize, self.dpi) self.width = metrics.xmax - metrics.xmin self.height = metrics.ymax - metrics.ymin self.depth = 0 01333 def shrink(self): Char.shrink(self) self._update_metrics() 01337 def grow(self): Char.grow(self) self._update_metrics() 01341 def render(self, x, y): """Render the character to the canvas""" self.font_output.render_glyph( x - self._metrics.xmin, y + self._metrics.ymin, self.font, self.font_class, self.c, self.fontsize, self.dpi) 01347 class List(Box): """A list of nodes (either horizontal or vertical). node135""" def __init__(self, elements): Box.__init__(self, 0., 0., 0.) self.shift_amount = 0. # An arbitrary offset self.children = elements # The child nodes of this list # The following parameters are set in the vpack and hpack functions self.glue_set = 0. # The glue setting of this list self.glue_sign = 0 # 0: normal, -1: shrinking, 1: stretching self.glue_order = 0 # The order of infinity (0 - 3) for the glue def __repr__(self): return '[%s <%.02f %.02f %.02f %.02f> %s]' % ( self.__internal_repr__(), self.width, self.height, self.depth, self.shift_amount, ' '.join([repr(x) for x in self.children])) 01366 def _determine_order(self, totals): """A helper function to determine the highest order of glue used by the members of this list. Used by vpack and hpack.""" o = 0 for i in range(len(totals) - 1, 0, -1): if totals[i] != 0.0: o = i break return o def _set_glue(self, x, sign, totals, error_type): o = self._determine_order(totals) self.glue_order = o self.glue_sign = sign if totals[o] != 0.: self.glue_set = x / totals[o] else: self.glue_sign = 0 self.glue_ratio = 0. if o == 0: if len(self.children): warn("%s %s: %r" % (error_type, self.__class__.__name__, self), MathTextWarning) 01390 def shrink(self): for child in self.children: child.shrink() Box.shrink(self) if self.size < NUM_SIZE_LEVELS: self.shift_amount *= SHRINK_FACTOR self.glue_set *= SHRINK_FACTOR 01398 def grow(self): for child in self.children: child.grow() Box.grow(self) self.shift_amount *= GROW_FACTOR self.glue_set *= GROW_FACTOR 01405 class Hlist(List): """A horizontal list of boxes. node135""" def __init__(self, elements, w=0., m='additional', do_kern=True): List.__init__(self, elements) if do_kern: self.kern() self.hpack() 01414 def kern(self): """Insert Kern nodes between Chars to set kerning. The Chars themselves determine the amount of kerning they need (in get_kerning), and this function just creates the linked list in the correct way.""" new_children = [] num_children = len(self.children) if num_children: for i in range(num_children): elem = self.children[i] if i < num_children - 1: next = self.children[i + 1] else: next = None new_children.append(elem) kerning_distance = elem.get_kerning(next) if kerning_distance != 0.: kern = Kern(kerning_distance) new_children.append(kern) self.children = new_children 01436 def hpack(self, w=0., m='additional'): """The main duty of hpack is to compute the dimensions of the resulting boxes, and to adjust the glue if one of those dimensions is pre-specified. The computed sizes normally enclose all of the material inside the new box; but some items may stick out if negative glue is used, if the box is overfull, or if a \vbox includes other boxes that have been shifted left. w: specifies a width m: is either 'exactly' or 'additional'. Thus, hpack(w, 'exactly') produces a box whose width is exactly w, while hpack (w, 'additional') yields a box whose width is the natural width plus w. The default values produce a box with the natural width. node644, node649""" # I don't know why these get reset in TeX. Shift_amount is pretty # much useless if we do. #self.shift_amount = 0. h = 0. d = 0. x = 0. total_stretch = [0.] * 4 total_shrink = [0.] * 4 for p in self.children: if isinstance(p, Char): x += p.width h = max(h, p.height) d = max(d, p.depth) elif isinstance(p, Box): x += p.width if not isinf(p.height) and not isinf(p.depth): s = getattr(p, 'shift_amount', 0.) h = max(h, p.height - s) d = max(d, p.depth + s) elif isinstance(p, Glue): glue_spec = p.glue_spec x += glue_spec.width total_stretch[glue_spec.stretch_order] += glue_spec.stretch total_shrink[glue_spec.shrink_order] += glue_spec.shrink elif isinstance(p, Kern): x += p.width self.height = h self.depth = d if m == 'additional': w += x self.width = w x = w - x if x == 0.: self.glue_sign = 0 self.glue_order = 0 self.glue_ratio = 0. return if x > 0.: self._set_glue(x, 1, total_stretch, "Overfull") else: self._set_glue(x, -1, total_shrink, "Underfull") 01495 class Vlist(List): """A vertical list of boxes. node137""" def __init__(self, elements, h=0., m='additional'): List.__init__(self, elements) self.vpack() 01502 def vpack(self, h=0., m='additional', l=float(inf)): """The main duty of vpack is to compute the dimensions of the resulting boxes, and to adjust the glue if one of those dimensions is pre-specified. h: specifies a height m: is either 'exactly' or 'additional'. l: a maximum height Thus, vpack(h, 'exactly') produces a box whose width is exactly w, while vpack(w, 'additional') yields a box whose width is the natural width plus w. The default values produce a box with the natural width. node644, node668""" # I don't know why these get reset in TeX. Shift_amount is pretty # much useless if we do. # self.shift_amount = 0. w = 0. d = 0. x = 0. total_stretch = [0.] * 4 total_shrink = [0.] * 4 for p in self.children: if isinstance(p, Box): x += d + p.height d = p.depth if not isinf(p.width): s = getattr(p, 'shift_amount', 0.) w = max(w, p.width + s) elif isinstance(p, Glue): x += d d = 0. glue_spec = p.glue_spec x += glue_spec.width total_stretch[glue_spec.stretch_order] += glue_spec.stretch total_shrink[glue_spec.shrink_order] += glue_spec.shrink elif isinstance(p, Kern): x += d + p.width d = 0. elif isinstance(p, Char): raise RuntimeError("Internal mathtext error: Char node found in Vlist.") self.width = w if d > l: x += d - l self.depth = l else: self.depth = d if m == 'additional': h += x self.height = h x = h - x if x == 0: self.glue_sign = 0 self.glue_order = 0 self.glue_ratio = 0. return if x > 0.: self._set_glue(x, 1, total_stretch, "Overfull") else: self._set_glue(x, -1, total_shrink, "Underfull") 01566 class Rule(Box): """A Rule node stands for a solid black rectangle; it has width, depth, and height fields just as in an Hlist. However, if any of these dimensions is inf, the actual value will be determined by running the rule up to the boundary of the innermost enclosing box. This is called a "running dimension." The width is never running in an Hlist; the height and depth are never running in a Vlist. node138""" def __init__(self, width, height, depth, state): Box.__init__(self, width, height, depth) self.font_output = state.font_output def render(self, x, y, w, h): self.font_output.render_rect_filled(x, y, x + w, y + h) 01581 class Hrule(Rule): """Convenience class to create a horizontal rule.""" def __init__(self, state): thickness = state.font_output.get_underline_thickness( state.font, state.fontsize, state.dpi) height = depth = thickness * 0.5 Rule.__init__(self, inf, height, depth, state) 01589 class Vrule(Rule): """Convenience class to create a vertical rule.""" def __init__(self, state): thickness = state.font_output.get_underline_thickness( state.font, state.fontsize, state.dpi) Rule.__init__(self, thickness, inf, inf, state) 01596 class Glue(Node): """Most of the information in this object is stored in the underlying GlueSpec class, which is shared between multiple glue objects. (This is a memory optimization which probably doesn't matter anymore, but it's easier to stick to what TeX does.) node149, node152""" def __init__(self, glue_type, copy=False): Node.__init__(self) self.glue_subtype = 'normal' if is_string_like(glue_type): glue_spec = GlueSpec.factory(glue_type) elif isinstance(glue_type, GlueSpec): glue_spec = glue_type else: raise ArgumentError("glue_type must be a glue spec name or instance.") if copy: glue_spec = glue_spec.copy() self.glue_spec = glue_spec 01615 def shrink(self): Node.shrink(self) if self.size < NUM_SIZE_LEVELS: if self.glue_spec.width != 0.: self.glue_spec = self.glue_spec.copy() self.glue_spec.width *= SHRINK_FACTOR 01622 def grow(self): Node.grow(self) if self.glue_spec.width != 0.: self.glue_spec = self.glue_spec.copy() self.glue_spec.width *= GROW_FACTOR 01628 class GlueSpec(object): """node150, node151""" def __init__(self, width=0., stretch=0., stretch_order=0, shrink=0., shrink_order=0): self.width = width self.stretch = stretch self.stretch_order = stretch_order self.shrink = shrink self.shrink_order = shrink_order def copy(self): return GlueSpec( self.width, self.stretch, self.stretch_order, self.shrink, self.shrink_order) def factory(cls, glue_type): return cls._types[glue_type] factory = classmethod(factory) GlueSpec._types = { 'fil': GlueSpec(0., 1., 1, 0., 0), 'fill': GlueSpec(0., 1., 2, 0., 0), 'filll': GlueSpec(0., 1., 3, 0., 0), 'neg_fil': GlueSpec(0., 0., 0, 1., 1), 'neg_fill': GlueSpec(0., 0., 0, 1., 2), 'neg_filll': GlueSpec(0., 0., 0, 1., 3), 'empty': GlueSpec(0., 0., 0, 0., 0), 'ss': GlueSpec(0., 1., 1, -1., 1) } # Some convenient ways to get common kinds of glue class Fil(Glue): def __init__(self): Glue.__init__(self, 'fil') class Fill(Glue): def __init__(self): Glue.__init__(self, 'fill') class Filll(Glue): def __init__(self): Glue.__init__(self, 'filll') class NegFil(Glue): def __init__(self): Glue.__init__(self, 'neg_fil') class NegFill(Glue): def __init__(self): Glue.__init__(self, 'neg_fill') class NegFilll(Glue): def __init__(self): Glue.__init__(self, 'neg_filll') class SsGlue(Glue): def __init__(self): Glue.__init__(self, 'ss') 01690 class HCentered(Hlist): """A convenience class to create an Hlist whose contents are centered within its enclosing box.""" def __init__(self, elements): Hlist.__init__(self, [SsGlue()] + elements + [SsGlue()], do_kern=False) 01697 class VCentered(Hlist): """A convenience class to create an Vlist whose contents are centered within its enclosing box.""" def __init__(self, elements): Vlist.__init__(self, [SsGlue()] + elements + [SsGlue()]) 01703 class Kern(Node): """A Kern node has a width field to specify a (normally negative) amount of spacing. This spacing correction appears in horizontal lists between letters like A and V when the font designer said that it looks better to move them closer together or further apart. A kern node can also appear in a vertical list, when its 'width' denotes additional spacing in the vertical direction. node155""" def __init__(self, width): Node.__init__(self) self.width = width def __repr__(self): return "k%.02f" % self.width 01718 def shrink(self): Node.shrink(self) if self.size < NUM_SIZE_LEVELS: self.width *= SHRINK_FACTOR 01723 def grow(self): Node.grow(self) self.width *= GROW_FACTOR 01727 class SubSuperCluster(Hlist): """This class is a sort of hack to get around that fact that this code doesn't parse to an mlist and then an hlist, but goes directly to hlists. This lets us store enough information in the hlist itself, namely the nucleas, sub- and super-script, such that if another script follows that needs to be attached, it can be reconfigured on the fly.""" def __init__(self): self.nucleus = None self.sub = None self.super = None Hlist.__init__(self, []) 01739 class AutoHeightChar(Hlist): """A class that will create a character as close to the given height and depth as possible. When using a font with multiple height versions of some characters (such as the BaKoMa fonts), the correct glyph will be selected, otherwise this will always just return a scaled version of the glyph.""" def __init__(self, c, height, depth, state, always=False): alternatives = state.font_output.get_sized_alternatives_for_symbol( state.font, c) state = state.copy() target_total = height + depth for fontname, sym in alternatives: state.font = fontname char = Char(sym, state) if char.height + char.depth >= target_total: break factor = target_total / (char.height + char.depth) state.fontsize *= factor char = Char(sym, state) shift = (depth - char.depth) Hlist.__init__(self, [char]) self.shift_amount = shift 01765 class AutoWidthChar(Hlist): """A class that will create a character as close to the given width as possible. When using a font with multiple width versions of some characters (such as the BaKoMa fonts), the correct glyph will be selected, otherwise this will always just return a scaled version of the glyph.""" def __init__(self, c, width, state, always=False, char_class=Char): alternatives = state.font_output.get_sized_alternatives_for_symbol( state.font, c) state = state.copy() for fontname, sym in alternatives: state.font = fontname char = char_class(sym, state) if char.width >= width: break factor = width / char.width state.fontsize *= factor char = char_class(sym, state) Hlist.__init__(self, [char]) self.width = char.width 01789 class Ship(object): """Once the boxes have been set up, this sends them to output. Since boxes can be inside of boxes inside of boxes, the main work of Ship is done by two mutually recursive routines, hlist_out and vlist_out , which traverse the Hlists and Vlists inside of horizontal and vertical boxes. The global variables used in TeX to store state as it processes have become member variables here. node592.""" def __call__(self, ox, oy, box): self.max_push = 0 # Deepest nesting of push commands so far self.cur_s = 0 self.cur_v = 0. self.cur_h = 0. self.off_h = ox self.off_v = oy + box.height self.hlist_out(box) def clamp(value): if value < -1000000000.: return -1000000000. if value > 1000000000.: return 1000000000. return value clamp = staticmethod(clamp) def hlist_out(self, box): cur_g = 0 cur_glue = 0. glue_order = box.glue_order glue_sign = box.glue_sign base_line = self.cur_v left_edge = self.cur_h self.cur_s += 1 self.max_push = max(self.cur_s, self.max_push) clamp = self.clamp for p in box.children: if isinstance(p, Char): p.render(self.cur_h + self.off_h, self.cur_v + self.off_v) self.cur_h += p.width elif isinstance(p, Kern): self.cur_h += p.width elif isinstance(p, List): # node623 if len(p.children) == 0: self.cur_h += p.width else: edge = self.cur_h self.cur_v = base_line + p.shift_amount if isinstance(p, Hlist): self.hlist_out(p) else: # p.vpack(box.height + box.depth, 'exactly') self.vlist_out(p) self.cur_h = edge + p.width self.cur_v = base_line elif isinstance(p, Box): # node624 rule_height = p.height rule_depth = p.depth rule_width = p.width if isinf(rule_height): rule_height = box.height if isinf(rule_depth): rule_depth = box.depth if rule_height > 0 and rule_width > 0: self.cur_v = baseline + rule_depth p.render(self.cur_h + self.off_h, self.cur_v + self.off_v, rule_width, rule_height) self.cur_v = baseline self.cur_h += rule_width elif isinstance(p, Glue): # node625 glue_spec = p.glue_spec rule_width = glue_spec.width - cur_g if glue_sign != 0: # normal if glue_sign == 1: # stretching if glue_spec.stretch_order == glue_order: cur_glue += glue_spec.stretch cur_g = round(clamp(float(box.glue_set) * cur_glue)) elif glue_spec.shrink_order == glue_order: cur_glue += glue_spec.shrink cur_g = round(clamp(float(box.glue_set) * cur_glue)) rule_width += cur_g self.cur_h += rule_width self.cur_s -= 1 def vlist_out(self, box): cur_g = 0 cur_glue = 0. glue_order = box.glue_order glue_sign = box.glue_sign self.cur_s += 1 self.max_push = max(self.max_push, self.cur_s) left_edge = self.cur_h self.cur_v -= box.height top_edge = self.cur_v clamp = self.clamp for p in box.children: if isinstance(p, Kern): self.cur_v += p.width elif isinstance(p, List): if len(p.children) == 0: self.cur_v += p.height + p.depth else: self.cur_v += p.height self.cur_h = left_edge + p.shift_amount save_v = self.cur_v p.width = box.width if isinstance(p, Hlist): self.hlist_out(p) else: self.vlist_out(p) self.cur_v = save_v + p.depth self.cur_h = left_edge elif isinstance(p, Box): rule_height = p.height rule_depth = p.depth rule_width = p.width if isinf(rule_width): rule_width = box.width rule_height += rule_depth if rule_height > 0 and rule_depth > 0: self.cur_v += rule_height p.render(self.cur_h + self.off_h, self.cur_v + self.off_v, rule_width, rule_height) elif isinstance(p, Glue): glue_spec = p.glue_spec rule_height = glue_spec.width - cur_g if glue_sign != 0: # normal if glue_sign == 1: # stretching if glue_spec.stretch_order == glue_order: cur_glue += glue_spec.stretch cur_g = round(clamp(float(box.glue_set) * cur_glue)) elif glue_spec.shrink_order == glue_order: # shrinking cur_glue += glue_spec.shrink cur_g = round(clamp(float(box.glue_set) * cur_glue)) rule_height += cur_g self.cur_v += rule_height elif isinstance(p, Char): raise RuntimeError("Internal mathtext error: Char node found in vlist") self.cur_s -= 1 ship = Ship() ############################################################################## # PARSER def Error(msg): def raise_error(s, loc, toks): raise ParseFatalException(msg + "\n" + s) empty = Empty() empty.setParseAction(raise_error) return empty class Parser(object): _binary_operators = Set(r''' + * \pm \sqcap \rhd \mp \sqcup \unlhd \times \vee \unrhd \div \wedge \oplus \ast \setminus \ominus \star \wr \otimes \circ \diamond \oslash \bullet \bigtriangleup \odot \cdot \bigtriangledown \bigcirc \cap \triangleleft \dagger \cup \triangleright \ddagger \uplus \lhd \amalg'''.split()) _relation_symbols = Set(r''' = < > : \leq \geq \equiv \models \prec \succ \sim \perp \preceq \succeq \simeq \mid \ll \gg \asymp \parallel \subset \supset \approx \bowtie \subseteq \supseteq \cong \Join \sqsubset \sqsupset \neq \smile \sqsubseteq \sqsupseteq \doteq \frown \in \ni \propto \vdash \dashv'''.split()) _arrow_symbols = Set(r''' \leftarrow \longleftarrow \uparrow \Leftarrow \Longleftarrow \Uparrow \rightarrow \longrightarrow \downarrow \Rightarrow \Longrightarrow \Downarrow \leftrightarrow \longleftrightarrow \updownarrow \Leftrightarrow \Longleftrightarrow \Updownarrow \mapsto \longmapsto \nearrow \hookleftarrow \hookrightarrow \searrow \leftharpoonup \rightharpoonup \swarrow \leftharpoondown \rightharpoondown \nwarrow \rightleftharpoons \leadsto'''.split()) _spaced_symbols = _binary_operators | _relation_symbols | _arrow_symbols _punctuation_symbols = Set(r', ; . ! \ldotp \cdotp'.split()) _overunder_symbols = Set(r''' \sum \prod \coprod \bigcap \bigcup \bigsqcup \bigvee \bigwedge \bigodot \bigotimes \bigoplus \biguplus '''.split()) _overunder_functions = Set( r"lim liminf limsup sup max min".split()) _dropsub_symbols = Set(r'''\int \oint'''.split()) _fontnames = Set("rm cal it tt sf bf default bb frak circled scr".split()) _function_names = Set(""" arccos csc ker min arcsin deg lg Pr arctan det lim sec arg dim liminf sin cos exp limsup sinh cosh gcd ln sup cot hom log tan coth inf max tanh""".split()) _ambiDelim = Set(r""" | \| / \backslash \uparrow \downarrow \updownarrow \Uparrow \Downarrow \Updownarrow .""".split()) _leftDelim = Set(r"( [ { \lfloor \langle \lceil".split()) _rightDelim = Set(r") ] } \rfloor \rangle \rceil".split()) def __init__(self): # All forward declarations are here font = Forward().setParseAction(self.font).setName("font") latexfont = Forward() subsuper = Forward().setParseAction(self.subsuperscript).setName("subsuper") placeable = Forward().setName("placeable") simple = Forward().setName("simple") autoDelim = Forward().setParseAction(self.auto_sized_delimiter) self._expression = Forward().setParseAction(self.finish).setName("finish") float = Regex(r"[-+]?([0-9]+\.?[0-9]*|\.[0-9]+)") lbrace = Literal('{').suppress() rbrace = Literal('}').suppress() start_group = (Optional(latexfont) - lbrace) start_group.setParseAction(self.start_group) end_group = rbrace.copy() end_group.setParseAction(self.end_group) bslash = Literal('\\') accent = oneOf(self._accent_map.keys() + list(self._wide_accents)) function = oneOf(list(self._function_names)) fontname = oneOf(list(self._fontnames)) latex2efont = oneOf(['math' + x for x in self._fontnames]) space =(FollowedBy(bslash) + oneOf([r'\ ', r'\/', r'\,', r'\;', r'\quad', r'\qquad', r'\!']) ).setParseAction(self.space).setName('space') customspace =(Literal(r'\hspace') - (( lbrace - float - rbrace ) | Error(r"Expected \hspace{n}")) ).setParseAction(self.customspace).setName('customspace') unicode_range = u"\U00000080-\U0001ffff" symbol =(Regex(UR"([a-zA-Z0-9 +\-*/<>=:,.;!'@()\[\]|%s])|(\\[%%${}\[\]_|])" % unicode_range) | (Combine( bslash + oneOf(tex2uni.keys()) ) + FollowedBy(Regex("[^a-zA-Z]"))) ).setParseAction(self.symbol).leaveWhitespace() c_over_c =(Suppress(bslash) + oneOf(self._char_over_chars.keys()) ).setParseAction(self.char_over_chars) accent = Group( Suppress(bslash) + accent - placeable ).setParseAction(self.accent).setName("accent") function =(Suppress(bslash) + function ).setParseAction(self.function).setName("function") group = Group( start_group + ZeroOrMore( autoDelim | simple) - end_group ).setParseAction(self.group).setName("group") font <<(Suppress(bslash) + fontname) latexfont <<(Suppress(bslash) + latex2efont) frac = Group( Suppress(Literal(r"\frac")) + ((group + group) | Error(r"Expected \frac{num}{den}")) ).setParseAction(self.frac).setName("frac") sqrt = Group( Suppress(Literal(r"\sqrt")) + Optional( Suppress(Literal("[")) - Regex("[0-9]+") - Suppress(Literal("]")), default = None ) + (group | Error("Expected \sqrt{value}")) ).setParseAction(self.sqrt).setName("sqrt") placeable <<(accent ^ function ^ (c_over_c | symbol) ^ group ^ frac ^ sqrt ) simple <<(space | customspace | font | subsuper ) subsuperop = oneOf(["_", "^"]) subsuper << Group( ( Optional(placeable) + OneOrMore( subsuperop - placeable ) ) | placeable ) ambiDelim = oneOf(list(self._ambiDelim)) leftDelim = oneOf(list(self._leftDelim)) rightDelim = oneOf(list(self._rightDelim)) autoDelim <<(Suppress(Literal(r"\left")) + ((leftDelim | ambiDelim) | Error("Expected a delimiter")) + Group( autoDelim ^ OneOrMore(simple)) + Suppress(Literal(r"\right")) + ((rightDelim | ambiDelim) | Error("Expected a delimiter")) ) math = OneOrMore( autoDelim ^ simple ).setParseAction(self.math).setName("math") math_delim = ~bslash + Literal('$') non_math = Regex(r"(?:(?:\\[$])|[^$])*" ).setParseAction(self.non_math).setName("non_math").leaveWhitespace() self._expression << ( non_math + ZeroOrMore( Suppress(math_delim) + Optional(math) + (Suppress(math_delim) | Error("Expected end of math '$'")) + non_math ) ) + StringEnd() self.clear() def clear(self): self._expr = None self._state_stack = None self._em_width_cache = {} def parse(self, s, fonts_object, fontsize, dpi): self._state_stack = [self.State(fonts_object, 'default', 'rm', fontsize, dpi)] try: self._expression.parseString(s) except ParseException, err: raise ValueError("\n".join([ "", err.line, " " * (err.column - 1) + "^", str(err)])) return self._expr # The state of the parser is maintained in a stack. Upon # entering and leaving a group { } or math/non-math, the stack # is pushed and popped accordingly. The current state always # exists in the top element of the stack. class State(object): def __init__(self, font_output, font, font_class, fontsize, dpi): self.font_output = font_output self._font = font self.font_class = font_class self.fontsize = fontsize self.dpi = dpi def copy(self): return Parser.State( self.font_output, self.font, self.font_class, self.fontsize, self.dpi) def _get_font(self): return self._font def _set_font(self, name): if name in ('it', 'rm', 'bf'): self.font_class = name self._font = name font = property(_get_font, _set_font) def get_state(self): return self._state_stack[-1] def pop_state(self): self._state_stack.pop() def push_state(self): self._state_stack.append(self.get_state().copy()) def finish(self, s, loc, toks): #~ print "finish", toks self._expr = Hlist(toks) return [self._expr] def math(self, s, loc, toks): #~ print "math", toks hlist = Hlist(toks) self.pop_state() return [hlist] def non_math(self, s, loc, toks): #~ print "non_math", toks s = toks[0].replace(r'\$', '$') symbols = [Char(c, self.get_state()) for c in s] hlist = Hlist(symbols) # We're going into math now, so set font to 'it' self.push_state() self.get_state().font = 'it' return [hlist] def _make_space(self, percentage): # All spaces are relative to em width state = self.get_state() key = (state.font, state.fontsize, state.dpi) width = self._em_width_cache.get(key) if width is None: metrics = state.font_output.get_metrics( state.font, 'it', 'm', state.fontsize, state.dpi) width = metrics.advance self._em_width_cache[key] = width return Kern(width * percentage) _space_widths = { r'\ ' : 0.3, r'\,' : 0.4, r'\;' : 0.8, r'\quad' : 1.6, r'\qquad' : 3.2, r'\!' : -0.4, r'\/' : 0.4 } def space(self, s, loc, toks): assert(len(toks)==1) num = self._space_widths[toks[0]] box = self._make_space(num) return [box] def customspace(self, s, loc, toks): return [self._make_space(float(toks[1]))] def symbol(self, s, loc, toks): # print "symbol", toks c = toks[0] try: char = Char(c, self.get_state()) except ValueError: raise ParseFatalException("Unknown symbol: %s" % c) if c in self._spaced_symbols: return [Hlist( [self._make_space(0.2), char, self._make_space(0.2)] , do_kern = False)] elif c in self._punctuation_symbols: return [Hlist( [char, self._make_space(0.2)] , do_kern = False)] return [char] _char_over_chars = { # The first 2 entires in the tuple are (font, char, sizescale) for # the two symbols under and over. The third element is the space # (in multiples of underline height) r'AA' : ( ('rm', 'A', 1.0), (None, '\circ', 0.5), 0.0), } def char_over_chars(self, s, loc, toks): sym = toks[0] state = self.get_state() thickness = state.font_output.get_underline_thickness( state.font, state.fontsize, state.dpi) under_desc, over_desc, space = \ self._char_over_chars.get(sym, (None, None, 0.0)) if under_desc is None: raise ParseFatalException("Error parsing symbol") over_state = state.copy() if over_desc[0] is not None: over_state.font = over_desc[0] over_state.fontsize *= over_desc[2] over = Accent(over_desc[1], over_state) under_state = state.copy() if under_desc[0] is not None: under_state.font = under_desc[0] under_state.fontsize *= under_desc[2] under = Char(under_desc[1], under_state) width = max(over.width, under.width) over_centered = HCentered([over]) over_centered.hpack(width, 'exactly') under_centered = HCentered([under]) under_centered.hpack(width, 'exactly') return Vlist([ over_centered, Vbox(0., thickness * space), under_centered ]) _accent_map = { r'hat' : r'\circumflexaccent', r'breve' : r'\combiningbreve', r'bar' : r'\combiningoverline', r'grave' : r'\combininggraveaccent', r'acute' : r'\combiningacuteaccent', r'ddot' : r'\combiningdiaeresis', r'tilde' : r'\combiningtilde', r'dot' : r'\combiningdotabove', r'vec' : r'\combiningrightarrowabove', r'"' : r'\combiningdiaeresis', r"`" : r'\combininggraveaccent', r"'" : r'\combiningacuteaccent', r'~' : r'\combiningtilde', r'.' : r'\combiningdotabove', r'^' : r'\circumflexaccent' } _wide_accents = Set(r"widehat widetilde".split()) def accent(self, s, loc, toks): assert(len(toks)==1) state = self.get_state() thickness = state.font_output.get_underline_thickness( state.font, state.fontsize, state.dpi) if len(toks[0]) != 2: raise ParseFatalException("Error parsing accent") accent, sym = toks[0] if accent in self._wide_accents: accent = AutoWidthChar( '\\' + accent, sym.width, state, char_class=Accent) else: accent = Accent(self._accent_map[accent], state) centered = HCentered([accent]) centered.hpack(sym.width, 'exactly') return Vlist([ centered, Vbox(0., thickness * 2.0), Hlist([sym]) ]) def function(self, s, loc, toks): #~ print "function", toks self.push_state() state = self.get_state() state.font = 'rm' hlist = Hlist([Char(c, state) for c in toks[0]]) self.pop_state() hlist.function_name = toks[0] return hlist def start_group(self, s, loc, toks): self.push_state() # Deal with LaTeX-style font tokens if len(toks): self.get_state().font = toks[0][4:] return [] def group(self, s, loc, toks): grp = Hlist(toks[0]) return [grp] def end_group(self, s, loc, toks): self.pop_state() return [] def font(self, s, loc, toks): assert(len(toks)==1) name = toks[0] self.get_state().font = name return [] def is_overunder(self, nucleus): if isinstance(nucleus, Char): return nucleus.c in self._overunder_symbols elif isinstance(nucleus, Hlist) and hasattr(nucleus, 'function_name'): return nucleus.function_name in self._overunder_functions return False def is_dropsub(self, nucleus): if isinstance(nucleus, Char): return nucleus.c in self._dropsub_symbols return False def is_slanted(self, nucleus): if isinstance(nucleus, Char): return nucleus.is_slanted() return False def subsuperscript(self, s, loc, toks): assert(len(toks)==1) # print 'subsuperscript', toks nucleus = None sub = None super = None if len(toks[0]) == 1: return toks[0].asList() elif len(toks[0]) == 2: op, next = toks[0] nucleus = Hbox(0.0) if op == '_': sub = next else: super = next elif len(toks[0]) == 3: nucleus, op, next = toks[0] if op == '_': sub = next else: super = next elif len(toks[0]) == 5: nucleus, op1, next1, op2, next2 = toks[0] if op1 == op2: if op1 == '_': raise ParseFatalException("Double subscript") else: raise ParseFatalException("Double superscript") if op1 == '_': sub = next1 super = next2 else: super = next1 sub = next2 else: raise ParseFatalException( "Subscript/superscript sequence is too long. " "Use braces { } to remove ambiguity.") state = self.get_state() rule_thickness = state.font_output.get_underline_thickness( state.font, state.fontsize, state.dpi) xHeight = state.font_output.get_xheight( state.font, state.fontsize, state.dpi) # Handle over/under symbols, such as sum or integral if self.is_overunder(nucleus): vlist = [] shift = 0. width = nucleus.width if super is not None: super.shrink() width = max(width, super.width) if sub is not None: sub.shrink() width = max(width, sub.width) if super is not None: hlist = HCentered([super]) hlist.hpack(width, 'exactly') vlist.extend([hlist, Kern(rule_thickness * 3.0)]) hlist = HCentered([nucleus]) hlist.hpack(width, 'exactly') vlist.append(hlist) if sub is not None: hlist = HCentered([sub]) hlist.hpack(width, 'exactly') vlist.extend([Kern(rule_thickness * 3.0), hlist]) shift = hlist.height + hlist.depth + rule_thickness * 2.0 vlist = Vlist(vlist) vlist.shift_amount = shift + nucleus.depth * 0.5 result = Hlist([vlist]) return [result] # Handle regular sub/superscripts shift_up = nucleus.height - SUBDROP * xHeight if self.is_dropsub(nucleus): shift_down = nucleus.depth + SUBDROP * xHeight else: shift_down = SUBDROP * xHeight if super is None: # node757 sub.shrink() x = Hlist([sub]) # x.width += SCRIPT_SPACE * xHeight shift_down = max(shift_down, SUB1) clr = x.height - (abs(xHeight * 4.0) / 5.0) shift_down = max(shift_down, clr) x.shift_amount = shift_down else: super.shrink() x = Hlist([super, Kern(SCRIPT_SPACE * xHeight)]) # x.width += SCRIPT_SPACE * xHeight clr = SUP1 * xHeight shift_up = max(shift_up, clr) clr = x.depth + (abs(xHeight) / 4.0) shift_up = max(shift_up, clr) if sub is None: x.shift_amount = -shift_up else: # Both sub and superscript sub.shrink() y = Hlist([sub]) # y.width += SCRIPT_SPACE * xHeight shift_down = max(shift_down, SUB1 * xHeight) clr = (2.0 * rule_thickness - ((shift_up - x.depth) - (y.height - shift_down))) if clr > 0.: shift_up += clr shift_down += clr if self.is_slanted(nucleus): x.shift_amount = DELTA * (shift_up + shift_down) x = Vlist([x, Kern((shift_up - x.depth) - (y.height - shift_down)), y]) x.shift_amount = shift_down result = Hlist([nucleus, x]) return [result] def frac(self, s, loc, toks): assert(len(toks)==1) assert(len(toks[0])==2) state = self.get_state() thickness = state.font_output.get_underline_thickness( state.font, state.fontsize, state.dpi) num, den = toks[0] num.shrink() den.shrink() cnum = HCentered([num]) cden = HCentered([den]) width = max(num.width, den.width) + thickness * 10. cnum.hpack(width, 'exactly') cden.hpack(width, 'exactly') vlist = Vlist([cnum, # numerator Vbox(0, thickness * 2.0), # space Hrule(state), # rule Vbox(0, thickness * 4.0), # space cden # denominator ]) # Shift so the fraction line sits in the middle of the # equals sign metrics = state.font_output.get_metrics( state.font, 'it', '=', state.fontsize, state.dpi) shift = (cden.height - ((metrics.ymax + metrics.ymin) / 2 - thickness * 3.0)) vlist.shift_amount = shift hlist = Hlist([vlist, Hbox(thickness * 2.)]) return [hlist] def sqrt(self, s, loc, toks): #~ print "sqrt", toks root, body = toks[0] state = self.get_state() thickness = state.font_output.get_underline_thickness( state.font, state.fontsize, state.dpi) if root is None: root = Box(0., 0., 0.) else: root = Hlist([Char(x, state) for x in root]) root.shrink() root.shrink() # Determine the height of the body, and add a little extra to # the height so it doesn't seem cramped height = body.height - body.shift_amount + thickness * 5.0 depth = body.depth + body.shift_amount check = AutoHeightChar(r'\__sqrt__', height, depth, state, always=True) height = check.height - check.shift_amount depth = check.depth + check.shift_amount # Put a little extra space to the left and right of the body padded_body = Hlist([Hbox(thickness * 2.0), body, Hbox(thickness * 2.0)]) rightside = Vlist([Hrule(state), Fill(), padded_body]) # Stretch the glue between the hrule and the body rightside.vpack(height + 1.0, depth, 'exactly') # Add the root and shift it upward so it is above the tick. # The value of 0.6 is a hard-coded hack ;) root_vlist = Vlist([Hlist([root])]) root_vlist.shift_amount = -height * 0.6 hlist = Hlist([root_vlist, # Root # Negative kerning to put root over tick Kern(-check.width * 0.5), check, # Check rightside]) # Body return [hlist] def auto_sized_delimiter(self, s, loc, toks): #~ print "auto_sized_delimiter", toks front, middle, back = toks state = self.get_state() height = max([x.height for x in middle]) depth = max([x.depth for x in middle]) parts = [] # \left. and \right. aren't supposed to produce any symbols if front != '.': parts.append(AutoHeightChar(front, height, depth, state)) parts.extend(middle.asList()) if back != '.': parts.append(AutoHeightChar(back, height, depth, state)) hlist = Hlist(parts) return hlist #### ############################################################################## # MAIN 02654 class MathTextParser(object): """ Parse the math expression s, return the (bbox, fonts) tuple needed to render it. fontsize must be in points return is width, height, fonts """ _parser = None _backend_mapping = { 'bitmap': MathtextBackendBitmap, 'agg' : MathtextBackendAgg, 'ps' : MathtextBackendPs, 'pdf' : MathtextBackendPdf, 'svg' : MathtextBackendSvg, 'cairo' : MathtextBackendCairo } _font_type_mapping = { 'cm' : BakomaFonts, 'stix' : StixFonts, 'stixsans' : StixSansFonts, 'custom' : UnicodeFonts } def __init__(self, output): self._output = output.lower() self._cache = maxdict(50) def parse(self, s, dpi = 72, prop = None): if prop is None: prop = FontProperties() cacheKey = (s, dpi, hash(prop)) result = self._cache.get(cacheKey) if result is not None: return result if self._output == 'PS' and rcParams['ps.useafm']: font_output = StandardPsFonts(prop) else: backend = self._backend_mapping[self._output]() fontset = rcParams['mathtext.fontset'] fontset_class = self._font_type_mapping.get(fontset.lower()) if fontset_class is not None: font_output = fontset_class(prop, backend) else: raise ValueError( "mathtext.fontset must be either 'cm', 'stix', " "'stixsans', or 'custom'") fontsize = prop.get_size_in_points() # This is a class variable so we don't rebuild the parser # with each request. if self._parser is None: self.__class__._parser = Parser() box = self._parser.parse(s, font_output, fontsize, dpi) font_output.set_canvas_size(box.width, box.height, box.depth) result = font_output.get_results(box) self._cache[cacheKey] = result # Free up the transient data structures self._parser.clear() # Fix cyclical references font_output.destroy() font_output.mathtext_backend.fonts_object = None font_output.mathtext_backend = None return result 02727 def to_mask(self, texstr, dpi=120, fontsize=14): """ Returns a tuple (*array*, *depth*) - *array* is an NxM uint8 alpha ubyte mask array of rasterized tex. - depth is the offset of the baseline from the bottom of the image in pixels. ''texstr'' A valid mathtext string, eg r'IQ: $\sigma_i=15$' ''dpi'' The dots-per-inch to render the text ''fontsize'' The font size in points """ assert(self._output=="bitmap") prop = FontProperties(size=fontsize) ftimage, depth = self.parse(texstr, dpi=dpi, prop=prop) x = ftimage.as_array() return x, depth 02753 def to_rgba(self, texstr, color='black', dpi=120, fontsize=14): """ Returns a tuple (*array*, *depth*) - *array* is an NxMx4 RGBA array of ubyte rasterized tex. - depth is the offset of the baseline from the bottom of the image in pixels. Returns a tuple (array, depth), where depth is the offset of the baseline from the bottom of the image. ''texstr'' A valid mathtext string, eg r'IQ: $\sigma_i=15$' ''color'' A valid matplotlib color argument ''dpi'' The dots-per-inch to render the text ''fontsize'' The font size in points """ x, depth = self.to_mask(texstr, dpi=dpi, fontsize=fontsize) r, g, b = mcolors.colorConverter.to_rgb(color) RGBA = np.zeros((x.shape[0], x.shape[1], 4), dtype=np.uint8) RGBA[:,:,0] = int(255*r) RGBA[:,:,1] = int(255*g) RGBA[:,:,2] = int(255*b) RGBA[:,:,3] = x return RGBA, depth 02787 def to_png(self, filename, texstr, color='black', dpi=120, fontsize=14): """ Writes a tex expression to a PNG file. Returns the offset of the baseline from the bottom of the image in pixels. ''filename'' A writable filename or fileobject ''texstr'' A valid mathtext string, eg r'IQ: $\sigma_i=15$' ''color'' A valid matplotlib color argument ''dpi'' The dots-per-inch to render the text ''fontsize'' The font size in points """ rgba, depth = self.to_rgba(texstr, color=color, dpi=dpi, fontsize=fontsize) numrows, numcols, tmp = rgba.shape _png.write_png(rgba.tostring(), numcols, numrows, filename) return depth 02816 def get_depth(self, texstr, dpi=120, fontsize=14): """ Returns the offset of the baseline from the bottom of the image in pixels. ''texstr'' A valid mathtext string, eg r'IQ: $\sigma_i=15$' ''dpi'' The dots-per-inch to render the text ''fontsize'' The font size in points """ assert(self._output=="bitmap") prop = FontProperties(size=fontsize) ftimage, depth = self.parse(texstr, dpi=dpi, prop=prop) return depth