PIL.BdfFontFile 源代码

#
# 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"
}


[文档]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.
[文档]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