lyx_mirror/lib/scripts/lyxpreview2ppm.py
Angus Leeming bc3f8c8225 The Instant Preview script in python.
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/branches/BRANCH_1_3_X@8810 a592a061-630c-0410-9148-cb99ea01b6c8
2004-06-09 12:35:49 +00:00

381 lines
11 KiB
Python
Executable File

#! /usr/bin/env python
# -*- coding: iso-8859-1 -*-
# file lyxpreview2ppm.py
# This file is part of LyX, the document processor.
# Licence details can be found in the file COPYING.
# author Angus Leeming
# Full author contact details are available in file CREDITS
# with much advice from members of the preview-latex project:
# David Kastrup, dak@gnu.org and
# Jan-Åke Larsson, jalar@mai.liu.se.
# and with much help testing the code under Windows from
# Paul A. Rubin, rubin@msu.edu.
# This script takes a LaTeX file and generates a collection of
# ppm image files, one per previewed snippet.
# Pre-requisites:
# * A latex executable;
# * preview.sty;
# * dvips;
# * gs;
# * pnmcrop (optional).
# preview.sty is part of the preview-latex project
# http://preview-latex.sourceforge.net/
# preview.sty can alternatively be obtained from
# CTAN/support/preview-latex/
# Example usage:
# lyxpreview2bitmap.py 0lyxpreview.tex 128 ppm
# This script takes three arguments:
# TEXFILE: the name of the .tex file to be converted.
# SCALEFACTOR: a scale factor, used to ascertain the resolution of the
# generated image which is then passed to gs.
# OUTPUTFORMAT: the format of the output bitmap image files.
# This particular script can produce only "ppm" format output.
# Decomposing TEXFILE's name as DIR/BASE.tex, this script will,
# if executed successfully, leave in DIR:
# * a (possibly large) number of image files with names
# like BASE[0-9]+.ppm
# * a file BASE.metrics, containing info needed by LyX to position
# the images correctly on the screen.
import glob, os, re, string, sys
import pipes, tempfile
use_win32_modules = 0
if os.name == "nt":
use_win32_modules = 1
try:
import pywintypes
import win32con
import win32event
import win32file
import win32pipe
import win32process
import win32security
import winerror
except:
sys.stderr.write("Consider installing the PyWin extension modules "\
"if you're irritated by the gs window being shown\n")
use_win32_modules = 0
# Pre-compiled regular expressions.
latex_file_re = re.compile("\.tex$")
def usage(prog_name):
return "Usage: %s <latex file> <dpi> ppm\n"\
% prog_name
def error(message):
sys.stderr.write(message + '\n')
sys.exit(1)
def find_exe(candidates, path):
for prog in candidates:
for directory in path:
if os.name == "nt":
full_path = os.path.join(directory, prog + ".exe")
else:
full_path = os.path.join(directory, prog)
if os.access(full_path, os.X_OK):
return full_path
return None
def find_exe_or_terminate(candidates, path):
exe = find_exe(candidates, path)
if exe == None:
error("Unable to find executable from '%s'" % string.join(candidates))
return exe
def run_command_popen(cmd):
handle = os.popen(cmd, 'r')
cmd_stdout = handle.read()
cmd_status = handle.close()
return cmd_status, cmd_stdout
def run_command_win32(cmd):
sa = win32security.SECURITY_ATTRIBUTES()
sa.bInheritHandle = True
stdout_r, stdout_w = win32pipe.CreatePipe(sa, 0)
si = win32process.STARTUPINFO()
si.dwFlags = (win32process.STARTF_USESTDHANDLES
| win32process.STARTF_USESHOWWINDOW)
si.wShowWindow = win32con.SW_HIDE
si.hStdOutput = stdout_w
process, thread, pid, tid = \
win32process.CreateProcess(None, cmd, None, None, True,
0, None, None, si)
if process == None:
return -1, ""
# Must close the write handle in this process, or ReadFile will hang.
stdout_w.Close()
# Read the pipe until we get an error (including ERROR_BROKEN_PIPE,
# which is okay because it happens when child process ends).
data = ""
error = 0
while 1:
try:
hr, buffer = win32file.ReadFile(stdout_r, 4096)
if hr != winerror.ERROR_IO_PENDING:
data = data + buffer
except pywintypes.error, e:
if e.args[0] != winerror.ERROR_BROKEN_PIPE:
error = 1
break
if error:
return -2, ""
# Everything okay - called process has closed the pipe.
# For safety, check that the process ended, then pick up its exit code.
win32event.WaitForSingleObject(process, win32event.INFINITE)
if win32process.GetExitCodeProcess(process):
return -3, ""
return None, data
def run_command(cmd):
if use_win32_modules:
return run_command_win32(cmd)
else:
return run_command_popen(cmd)
def extract_metrics_info(log_file, metrics_file):
metrics = open(metrics_file, 'w')
log_re = re.compile("Preview: [ST]")
success = 0
for line in open(log_file, 'r').readlines():
match = log_re.match(line)
if match != None:
success = 1
metrics.write("%s\n" % line)
return success
def extract_resolution(log_file, dpi):
fontsize_re = re.compile("Preview: Fontsize")
magnification_re = re.compile("Preview: Magnification")
extract_decimal_re = re.compile("([0-9\.]+)")
extract_integer_re = re.compile("([0-9]+)")
found_fontsize = 0
found_magnification = 0
# Default values
magnification = 1000.0
fontsize = 0.0
for line in open(log_file, 'r').readlines():
if found_fontsize and found_magnification:
break
if not found_fontsize:
match = fontsize_re.match(line)
if match != None:
match = extract_decimal_re.search(line)
if match == None:
error("Unable to parse: %s" % line)
fontsize = string.atof(match.group(1))
found_fontsize = 1
continue
if not found_magnification:
match = magnification_re.match(line)
if match != None:
match = extract_integer_re.search(line)
if match == None:
error("Unable to parse: %s" % line)
magnification = string.atof(match.group(1))
found_magnification = 1
continue
return dpi * (10.0 / fontsize) * (1000.0 / magnification)
def get_version_info():
version_re = re.compile("([0-9])\.([0-9])")
match = version_re.match(sys.version)
if match == None:
error("Unable to extract version info from 'sys.version'")
return string.atoi(match.group(1)), string.atoi(match.group(2))
def copyfileobj(fsrc, fdst, rewind=0, length=16*1024):
"""copy data from file-like object fsrc to file-like object fdst"""
if rewind:
fsrc.flush()
fsrc.seek(0)
while 1:
buf = fsrc.read(length)
if not buf:
break
fdst.write(buf)
class TempFile:
"""clone of tempfile.TemporaryFile to use with python < 2.0."""
# Cache the unlinker so we don't get spurious errors at shutdown
# when the module-level "os" is None'd out. Note that this must
# be referenced as self.unlink, because the name TempFile
# may also get None'd out before __del__ is called.
unlink = os.unlink
def __init__(self):
self.filename = tempfile.mktemp()
self.file = open(self.filename,"w+b")
self.close_called = 0
def close(self):
if not self.close_called:
self.close_called = 1
self.file.close()
self.unlink(self.filename)
def __del__(self):
self.close()
def read(self, size = -1):
return self.file.read(size)
def write(self, line):
return self.file.write(line)
def seek(self, offset):
return self.file.seek(offset)
def flush(self):
return self.file.flush()
def mkstemp():
"""create a secure temporary file and return its object-like file"""
major, minor = get_version_info()
if major >= 2 and minor >= 0:
return tempfile.TemporaryFile()
else:
return TempFile()
def crop_files(pnmcrop, basename):
t = pipes.Template()
t.append("%s -left" % pnmcrop, '--')
t.append("%s -right" % pnmcrop, '--')
for file in glob.glob("%s*.ppm" % basename):
tmp = mkstemp()
new = t.open(file, "r")
copyfileobj(new, tmp)
if not new.close():
copyfileobj(tmp, open(file,"wb"), 1)
def main(argv):
# Parse and manipulate the command line arguments.
if len(argv) != 4:
error(usage(argv[0]))
dir, latex_file = os.path.split(argv[1])
if len(dir) != 0:
os.chdir(dir)
dpi = string.atoi(argv[2])
output_format = argv[3]
if output_format != "ppm":
error("This script can generate ppm format images only.")
# External programs used by the script.
path = string.split(os.getenv("PATH"), os.pathsep)
latex = find_exe_or_terminate(["pplatex", "latex2e", "latex"], path)
dvips = find_exe_or_terminate(["dvips"], path)
gs = find_exe_or_terminate(["gswin32", "gs"], path)
pnmcrop = find_exe(["pnmcrop"], path)
# Compile the latex file.
latex_call = "%s %s" % (latex, latex_file)
latex_status, latex_stdout = run_command(latex_call)
if latex_status != None:
error("%s failed to compile %s" \
% (os.path.basename(latex), latex_file))
# Run the dvi file through dvips.
dvi_file = latex_file_re.sub(".dvi", latex_file)
ps_file = latex_file_re.sub(".ps", latex_file)
dvips_call = "%s -o %s %s" % (dvips, ps_file, dvi_file)
dvips_status, dvips_stdout = run_command(dvips_call)
if dvips_status != None:
error("Failed: %s %s" % (os.path.basename(dvips), dvi_file))
# Extract resolution data for gs from the log file.
log_file = latex_file_re.sub(".log", latex_file)
resolution = extract_resolution(log_file, dpi)
# Older versions of gs have problems with a large degree of
# anti-aliasing at high resolutions
alpha = 4
if resolution > 150:
alpha = 2
# Generate the bitmap images
gs_call = "%s -dNOPAUSE -dBATCH -dSAFER -sDEVICE=pnmraw " \
"-sOutputFile=%s%%d.ppm " \
"-dGraphicsAlphaBit=%d -dTextAlphaBits=%d " \
"-r%f %s" \
% (gs, latex_file_re.sub("", latex_file), \
alpha, alpha, resolution, ps_file)
gs_status, gs_stdout = run_command(gs_call)
if gs_status != None:
error("Failed: %s %s" % (os.path.basename(gs), ps_file))
# Crop the images
if pnmcrop != None:
crop_files(pnmcrop, latex_file_re.sub("", latex_file))
# Extract metrics info from the log file.
metrics_file = latex_file_re.sub(".metrics", latex_file)
if not extract_metrics_info(log_file, metrics_file):
error("Failed to extract metrics info from %s" % log_file)
return 0
if __name__ == "__main__":
main(sys.argv)