Pillow/PIL/BdfFontFile.py
2015-11-09 23:34:34 +11:00

133 lines
3.3 KiB
Python

#
# The Python Imaging Library
# $Id$
#
# bitmap distribution font (bdf) file parser
#
# history:
# 1996-05-16 fl created (as bdf2pil)
# 1997-08-25 fl converted to FontFile driver
# 2001-05-25 fl removed bogus __init__ call
# 2002-11-20 fl robustification (from Kevin Cazabon, Dmitry Vasiliev)
# 2003-04-22 fl more robustification (from Graham Dumpleton)
#
# Copyright (c) 1997-2003 by Secret Labs AB.
# Copyright (c) 1997-2003 by Fredrik Lundh.
#
# See the README file for information on usage and redistribution.
#
from PIL import Image
from PIL import FontFile
# --------------------------------------------------------------------
# parse X Bitmap Distribution Format (BDF)
# --------------------------------------------------------------------
bdf_slant = {
"R": "Roman",
"I": "Italic",
"O": "Oblique",
"RI": "Reverse Italic",
"RO": "Reverse Oblique",
"OT": "Other"
}
bdf_spacing = {
"P": "Proportional",
"M": "Monospaced",
"C": "Cell"
}
def bdf_char(f):
# skip to STARTCHAR
while True:
s = f.readline()
if not s:
return None
if s[:9] == b"STARTCHAR":
break
id = s[9:].strip().decode('ascii')
# load symbol properties
props = {}
while True:
s = f.readline()
if not s or s[:6] == b"BITMAP":
break
i = s.find(b" ")
props[s[:i].decode('ascii')] = s[i+1:-1].decode('ascii')
# load bitmap
bitmap = []
while True:
s = f.readline()
if not s or s[:7] == b"ENDCHAR":
break
bitmap.append(s[:-1])
bitmap = b"".join(bitmap)
[x, y, l, d] = [int(p) for p in props["BBX"].split()]
[dx, dy] = [int(p) for p in props["DWIDTH"].split()]
bbox = (dx, dy), (l, -d-y, x+l, -d), (0, 0, x, y)
try:
im = Image.frombytes("1", (x, y), bitmap, "hex", "1")
except ValueError:
# deal with zero-width characters
im = Image.new("1", (x, y))
return id, int(props["ENCODING"]), bbox, im
##
# Font file plugin for the X11 BDF format.
class BdfFontFile(FontFile.FontFile):
def __init__(self, fp):
FontFile.FontFile.__init__(self)
s = fp.readline()
if s[:13] != b"STARTFONT 2.1":
raise SyntaxError("not a valid BDF file")
props = {}
comments = []
while True:
s = fp.readline()
if not s or s[:13] == b"ENDPROPERTIES":
break
i = s.find(b" ")
props[s[:i].decode('ascii')] = s[i+1:-1].decode('ascii')
if s[:i] in [b"COMMENT", b"COPYRIGHT"]:
if s.find(b"LogicalFontDescription") < 0:
comments.append(s[i+1:-1].decode('ascii'))
# font = props["FONT"].split("-")
# font[4] = bdf_slant[font[4].upper()]
# font[11] = bdf_spacing[font[11].upper()]
# ascent = int(props["FONT_ASCENT"])
# descent = int(props["FONT_DESCENT"])
# fontname = ";".join(font[1:])
# print "#", fontname
# for i in comments:
# print "#", i
while True:
c = bdf_char(fp)
if not c:
break
id, ch, (xy, dst, src), im = c
if 0 <= ch < len(self.glyph):
self.glyph[ch] = xy, dst, src, im