/usr/share/pyshared/pyx/dvi/texfont.py is in python-pyx 0.12.1-2.
This file is owned by root:root, with mode 0o644.
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#
#
# Copyright (C) 2007-2011 Jörg Lehmann <joergl@users.sourceforge.net>
# Copyright (C) 2007-2011 André Wobst <wobsta@users.sourceforge.net>
#
# This file is part of PyX (http://pyx.sourceforge.net/).
#
# PyX is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# PyX is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with PyX; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
from pyx import bbox, canvasitem, font, filelocator
import tfmfile, vffile
class TeXFontError(Exception): pass
class TeXfont:
def __init__(self, name, c, q, d, tfmconv, pyxconv, debug=0):
self.name = name
self.q = q # desired size of font (fix_word) in TeX points
self.d = d # design size of font (fix_word) in TeX points
self.tfmconv = tfmconv # conversion factor from tfm units to dvi units
self.pyxconv = pyxconv # conversion factor from dvi units to PostScript points
file = filelocator.open(self.name, [filelocator.format.tfm], "rb")
self.TFMfile = tfmfile.TFMfile(file, debug)
file.close()
# We only check for equality of font checksums if none of them
# is zero. The case c == 0 happend in some VF files and
# according to the VFtoVP documentation, paragraph 40, a check
# is only performed if TFMfile.checksum > 0. Anyhow, being
# more generous here seems to be reasonable
if self.TFMfile.checksum != c and self.TFMfile.checksum != 0 and c != 0:
raise TeXFontError("check sums do not agree: %d vs. %d" %
(self.TFMfile.checksum, c))
# Check whether the given design size matches the one defined in the tfm file
if abs(self.TFMfile.designsize - d) > 4: # XXX: why the deviation?
raise TeXFontError("design sizes do not agree: %d vs. %d" % (self.TFMfile.designsize, d))
#if q < 0 or q > 134217728:
# raise TeXFontError("font '%s' not loaded: bad scale" % self.name)
if d < 0 or d > 134217728:
raise TeXFontError("font '%s' not loaded: bad design size" % self.name)
def __str__(self):
return "font %s designed at %g TeX pts used at %g TeX pts" % (self.name,
16.0*self.d/16777216L,
16.0*self.q/16777216L)
def getsize_pt(self):
""" return size of font in (PS) points """
# The factor 16L/16777216L=2**(-20) converts a fix_word (here self.q)
# to the corresponding float. Furthermore, we have to convert from TeX
# points to points, hence the factor 72/72.27.
return 72/72.27 * 16*self.q/16777216
def _convert_tfm_to_dvi(self, length):
# doing the integer math with long integers will lead to different roundings
# return 16*length*int(round(self.q*self.tfmconv))/16777216
# Knuth instead suggests the following algorithm based on 4 byte integer logic only
# z = int(round(self.q*self.tfmconv))
# b0, b1, b2, b3 = [ord(c) for c in struct.pack(">L", length)]
# assert b0 == 0 or b0 == 255
# shift = 4
# while z >= 8388608:
# z >>= 1
# shift -= 1
# assert shift >= 0
# result = ( ( ( ( ( b3 * z ) >> 8 ) + ( b2 * z ) ) >> 8 ) + ( b1 * z ) ) >> shift
# if b0 == 255:
# result = result - (z << (8-shift))
# however, we can simplify this using a single long integer multiplication,
# but take into account the transformation of z
z = int(round(self.q*self.tfmconv))
assert -16777216 <= length < 16777216 # -(1 << 24) <= length < (1 << 24)
assert z < 134217728 # 1 << 27
shift = 20 # 1 << 20
while z >= 8388608: # 1 << 23
z >>= 1
shift -= 1
# length*z is a long integer, but the result will be a regular integer
return int(length*long(z) >> shift)
def _convert_tfm_to_pt(self, length):
return (16*long(round(length*float(self.q)*self.tfmconv))/16777216) * self.pyxconv
# routines returning lengths as integers in dvi units
def getwidth_dvi(self, charcode):
return self._convert_tfm_to_dvi(self.TFMfile.width[self.TFMfile.char_info[charcode].width_index])
def getheight_dvi(self, charcode):
return self._convert_tfm_to_dvi(self.TFMfile.height[self.TFMfile.char_info[charcode].height_index])
def getdepth_dvi(self, charcode):
return self._convert_tfm_to_dvi(self.TFMfile.depth[self.TFMfile.char_info[charcode].depth_index])
def getitalic_dvi(self, charcode):
return self._convert_tfm_to_dvi(self.TFMfile.italic[self.TFMfile.char_info[charcode].italic_index])
# routines returning lengths as floats in PostScript points
def getwidth_pt(self, charcode):
return self._convert_tfm_to_pt(self.TFMfile.width[self.TFMfile.char_info[charcode].width_index])
def getheight_pt(self, charcode):
return self._convert_tfm_to_pt(self.TFMfile.height[self.TFMfile.char_info[charcode].height_index])
def getdepth_pt(self, charcode):
return self._convert_tfm_to_pt(self.TFMfile.depth[self.TFMfile.char_info[charcode].depth_index])
def getitalic_pt(self, charcode):
return self._convert_tfm_to_pt(self.TFMfile.italic[self.TFMfile.char_info[charcode].italic_index])
def text_pt(self, x_pt, y_pt, charcodes, fontmap=None):
return TeXtext_pt(self, x_pt, y_pt, charcodes, self.getsize_pt(), fontmap=fontmap)
def getMAPline(self, fontmap):
if self.name not in fontmap:
raise RuntimeError("missing font information for '%s'; check fontmapping file(s)" % self.name)
return fontmap[self.name]
class virtualfont(TeXfont):
def __init__(self, name, file, c, q, d, tfmconv, pyxconv, debug=0):
TeXfont.__init__(self, name, c, q, d, tfmconv, pyxconv, debug)
self.vffile = vffile.vffile(file, 1.0*q/d, tfmconv, pyxconv, debug > 1)
def getfonts(self):
""" return fonts used in virtual font itself """
return self.vffile.getfonts()
def getchar(self, cc):
""" return dvi chunk corresponding to char code cc """
return self.vffile.getchar(cc)
def text_pt(self, *args, **kwargs):
raise RuntimeError("you don't know what you're doing")
class TeXtext_pt(font.text_pt):
def __init__(self, font, x_pt, y_pt, charcodes, size_pt, fontmap=None):
self.font = font
self.x_pt = x_pt
self.y_pt = y_pt
self.charcodes = charcodes
self.size_pt = size_pt
self.fontmap = fontmap
self.width_pt = sum([self.font.getwidth_pt(charcode) for charcode in charcodes])
self.height_pt = max([self.font.getheight_pt(charcode) for charcode in charcodes])
self.depth_pt = max([self.font.getdepth_pt(charcode) for charcode in charcodes])
self._bbox = bbox.bbox_pt(self.x_pt, self.y_pt-self.depth_pt, self.x_pt+self.width_pt, self.y_pt+self.height_pt)
def bbox(self):
return self._bbox
def _text(self, writer):
if self.fontmap is not None:
mapline = self.font.getMAPline(self.fontmap)
else:
mapline = self.font.getMAPline(writer.getfontmap())
font = mapline.getfont()
return font.text_pt(self.x_pt, self.y_pt, self.charcodes, self.size_pt, decoding=mapline.getencoding(), slant=mapline.slant, ignorebbox=True)
def textpath(self):
from pyx import pswriter
return self._text(pswriter._PSwriter()).textpath()
def processPS(self, file, writer, context, registry, bbox):
bbox += self.bbox()
self._text(writer).processPS(file, writer, context, registry, bbox)
def processPDF(self, file, writer, context, registry, bbox):
bbox += self.bbox()
self._text(writer).processPDF(file, writer, context, registry, bbox)
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