发布于 2015-09-11 16:12:10 | 134 次阅读 | 评论: 0 | 来源: 网络整理
#
# The Python Imaging Library
# $Id$
#
# simple postscript graphics interface
#
# History:
# 1996-04-20 fl Created
# 1999-01-10 fl Added gsave/grestore to image method
# 2005-05-04 fl Fixed floating point issue in image (from Eric Etheridge)
#
# Copyright (c) 1997-2005 by Secret Labs AB. All rights reserved.
# Copyright (c) 1996 by Fredrik Lundh.
#
# See the README file for information on usage and redistribution.
#
from __future__ import print_function
from PIL import EpsImagePlugin
##
# Simple Postscript graphics interface.
[docs]class PSDraw:
"""
Sets up printing to the given file. If **file** is omitted,
:py:attr:`sys.stdout` is assumed.
"""
def __init__(self, fp=None):
if not fp:
import sys
fp = sys.stdout
self.fp = fp
[docs] def begin_document(self, id = None):
"""Set up printing of a document. (Write Postscript DSC header.)"""
# FIXME: incomplete
self.fp.write("%!PS-Adobe-3.0n"
"saven"
"/showpage { } defn"
"%%EndCommentsn"
"%%BeginDocumentn")
#self.fp.write(ERROR_PS) # debugging!
self.fp.write(EDROFF_PS)
self.fp.write(VDI_PS)
self.fp.write("%%EndPrologn")
self.isofont = {}
[docs] def end_document(self):
"""Ends printing. (Write Postscript DSC footer.)"""
self.fp.write("%%EndDocumentn"
"restore showpagen"
"%%Endn")
if hasattr(self.fp, "flush"):
self.fp.flush()
[docs] def setfont(self, font, size):
"""
Selects which font to use.
:param font: A Postscript font name
:param size: Size in points.
"""
if font not in self.isofont:
# reencode font
self.fp.write("/PSDraw-%s ISOLatin1Encoding /%s En" %
(font, font))
self.isofont[font] = 1
# rough
self.fp.write("/F0 %d /PSDraw-%s Fn" % (size, font))
[docs] def setink(self, ink):
"""
.. warning::
This has been in the PIL API for ages but was never implemented.
"""
print("*** NOT YET IMPLEMENTED ***")
[docs] def line(self, xy0, xy1):
"""
Draws a line between the two points. Coordinates are given in
Postscript point coordinates (72 points per inch, (0, 0) is the lower
left corner of the page).
"""
xy = xy0 + xy1
self.fp.write("%d %d %d %d Vln" % xy)
[docs] def rectangle(self, box):
"""
Draws a rectangle.
:param box: A 4-tuple of integers whose order and function is currently
undocumented.
Hint: the tuple is passed into this format string:
.. code-block:: python
%d %d M %d %d 0 Vrn
"""
self.fp.write("%d %d M %d %d 0 Vrn" % box)
[docs] def text(self, xy, text):
"""
Draws text at the given position. You must use
:py:meth:`~PIL.PSDraw.PSDraw.setfont` before calling this method.
"""
text = "(".join(text.split("("))
text = ")".join(text.split(")"))
xy = xy + (text,)
self.fp.write("%d %d M (%s) Sn" % xy)
[docs] def image(self, box, im, dpi = None):
"""Draw a PIL image, centered in the given box."""
# default resolution depends on mode
if not dpi:
if im.mode == "1":
dpi = 200 # fax
else:
dpi = 100 # greyscale
# image size (on paper)
x = float(im.size[0] * 72) / dpi
y = float(im.size[1] * 72) / dpi
# max allowed size
xmax = float(box[2] - box[0])
ymax = float(box[3] - box[1])
if x > xmax:
y = y * xmax / x; x = xmax
if y > ymax:
x = x * ymax / y; y = ymax
dx = (xmax - x) / 2 + box[0]
dy = (ymax - y) / 2 + box[1]
self.fp.write("gsaven%f %f translaten" % (dx, dy))
if (x, y) != im.size:
# EpsImagePlugin._save prints the image at (0,0,xsize,ysize)
sx = x / im.size[0]
sy = y / im.size[1]
self.fp.write("%f %f scalen" % (sx, sy))
EpsImagePlugin._save(im, self.fp, None, 0)
self.fp.write("ngrestoren")
# --------------------------------------------------------------------
# Postscript driver
#
# EDROFF.PS -- Postscript driver for Edroff 2
#
# History:
# 94-01-25 fl: created (edroff 2.04)
#
# Copyright (c) Fredrik Lundh 1994.
#
EDROFF_PS = """
/S { show } bind def
/P { moveto show } bind def
/M { moveto } bind def
/X { 0 rmoveto } bind def
/Y { 0 exch rmoveto } bind def
/E { findfont
dup maxlength dict begin
{
1 index /FID ne { def } { pop pop } ifelse
} forall
/Encoding exch def
dup /FontName exch def
currentdict end definefont pop
} bind def
/F { findfont exch scalefont dup setfont
[ exch /setfont cvx ] cvx bind def
} bind def
"""
#
# VDI.PS -- Postscript driver for VDI meta commands
#
# History:
# 94-01-25 fl: created (edroff 2.04)
#
# Copyright (c) Fredrik Lundh 1994.
#
VDI_PS = """
/Vm { moveto } bind def
/Va { newpath arcn stroke } bind def
/Vl { moveto lineto stroke } bind def
/Vc { newpath 0 360 arc closepath } bind def
/Vr { exch dup 0 rlineto
exch dup neg 0 exch rlineto
exch neg 0 rlineto
0 exch rlineto
100 div setgray fill 0 setgray } bind def
/Tm matrix def
/Ve { Tm currentmatrix pop
translate scale newpath 0 0 .5 0 360 arc closepath
Tm setmatrix
} bind def
/Vf { currentgray exch setgray fill setgray } bind def
"""
#
# ERROR.PS -- Error handler
#
# History:
# 89-11-21 fl: created (pslist 1.10)
#
ERROR_PS = """
/landscape false def
/errorBUF 200 string def
/errorNL { currentpoint 10 sub exch pop 72 exch moveto } def
errordict begin /handleerror {
initmatrix /Courier findfont 10 scalefont setfont
newpath 72 720 moveto $error begin /newerror false def
(PostScript Error) show errorNL errorNL
(Error: ) show
/errorname load errorBUF cvs show errorNL errorNL
(Command: ) show
/command load dup type /stringtype ne { errorBUF cvs } if show
errorNL errorNL
(VMstatus: ) show
vmstatus errorBUF cvs show ( bytes available, ) show
errorBUF cvs show ( bytes used at level ) show
errorBUF cvs show errorNL errorNL
(Operand stargck: ) show errorNL /ostargck load {
dup type /stringtype ne { errorBUF cvs } if 72 0 rmoveto show errorNL
} forall errorNL
(Execution stargck: ) show errorNL /estargck load {
dup type /stringtype ne { errorBUF cvs } if 72 0 rmoveto show errorNL
} forall
end showpage
} def end
"""