#! /usr/bin/env python # -*- coding: utf-8 -*- # file lyxpreview2bitmap.py # This file is part of LyX, the document processor. # Licence details can be found in the file COPYING. # author Angus Leeming # with much advice from members of the preview-latex project: # David Kastrup, dak@gnu.org and # Jan-Åke Larsson, jalar@mai.liu.se. # Full author contact details are available in file CREDITS # This script takes a LaTeX file and generates a collection of # png or ppm image files, one per previewed snippet. # Pre-requisites: # * A latex executable; # * preview.sty; # * dvipng; # * dv2dt; # * pngtoppm (if outputing ppm format images). # preview.sty and dvipng are 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 png 0lyxpreview.tex 128 000000 faf0e6 # This script takes six arguments: # FORMAT: The desired output format. Either 'png' or 'ppm'. # TEXFILE: the name of the .tex file to be converted. # DPI: a scale factor, used to ascertain the resolution of the # generated image which is then passed to gs. # FG_COLOR: the foreground color as a hexadecimal string, eg '000000'. # BG_COLOR: the background color as a hexadecimal string, eg 'faf0e6'. # CONVERTER: the converter (optional). Default is latex. # 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]+.png # * a file BASE.metrics, containing info needed by LyX to position # the images correctly on the screen. # What does this script do? # 1) Call latex/pdflatex/xelatex/whatever (CONVERTER parameter) # 2) If the output is a PDF fallback to legacy # 3) Otherwise check each page of the DVI (with dv2dt) looking for # PostScript literals, not well supported by dvipng. Pages # containing them are passed to the legacy method in a new LaTeX file. # 4) Call dvipng on the pages without PS literals # 5) Join metrics info coming from both methods (legacy and dvipng) # and write them to file # dvipng is fast but gives problem in several cases, like with # PSTricks, TikZ and other packages using PostScript literals # for all these cases the legacy route is taken (step 3). # Moreover dvipng can't work with PDF files, so, if the CONVERTER # paramter is pdflatex we have to fallback to legacy route (step 2). import glob, os, re, string, sys from legacy_lyxpreview2ppm import legacy_conversion, \ legacy_conversion_step2, legacy_extract_metrics_info, filter_pages from lyxpreview_tools import copyfileobj, error, find_exe, \ find_exe_or_terminate, make_texcolor, mkstemp, run_command, warning, \ write_metrics_info, join_metrics_and_rename # Pre-compiled regular expressions. latex_file_re = re.compile("\.tex$") # PATH environment variable path = string.split(os.environ["PATH"], os.pathsep) def usage(prog_name): return "Usage: %s <format> <latex file> <dpi> <fg color> <bg color>\n"\ "\twhere the colors are hexadecimal strings, eg 'faf0e6'"\ % prog_name # Returns a list of tuples containing page number and ascent fraction # extracted from dvipng output. # Use write_metrics_info to create the .metrics file with this info def extract_metrics_info(dvipng_stdout): # "\[[0-9]+" can match two kinds of numbers: page numbers from dvipng # and glyph numbers from mktexpk. The glyph numbers always match # "\[[0-9]+\]" while the page number never is followed by "\]". Thus: page_re = re.compile("\[([0-9]+)[^]]"); metrics_re = re.compile("depth=(-?[0-9]+) height=(-?[0-9]+)") success = 0 page = "" pos = 0 results = [] while 1: match = page_re.search(dvipng_stdout, pos) if match == None: break page = match.group(1) pos = match.end() match = metrics_re.search(dvipng_stdout, pos) if match == None: break success = 1 # Calculate the 'ascent fraction'. descent = string.atof(match.group(1)) ascent = string.atof(match.group(2)) frac = 0.5 if ascent >= 0 or descent >= 0: if abs(ascent + descent) > 0.1: frac = ascent / (ascent + descent) # Sanity check if frac < 0: frac = 0.5 results.append((int(page), frac)) pos = match.end() + 2 if success == 0: error("Failed to extract metrics info from dvipng") return results def color_pdf(latex_file, bg_color, fg_color): use_preview_pdf_re = re.compile("(\s*\\\\usepackage\[[^]]+)((pdftex|xetex)\]{preview})") tmp = mkstemp() fg = "" if fg_color != "0.000000,0.000000,0.000000": fg = ' \\AtBeginDocument{\\let\\oldpreview\\preview\\renewcommand\\preview{\\oldpreview\\color[rgb]{%s}}}\n' % (fg_color) success = 0 try: for line in open(latex_file, 'r').readlines(): match = use_preview_pdf_re.match(line) if match == None: tmp.write(line) continue success = 1 tmp.write(" \\usepackage{color}\n" \ " \\pagecolor[rgb]{%s}\n" \ "%s" \ "%s\n" \ % (bg_color, fg, match.group())) continue except: # Unable to open the file, but do nothing here because # the calling function will act on the value of 'success'. warning('Warning in color_pdf! Unable to open "%s"' % latex_file) warning(`sys.exc_type` + ',' + `sys.exc_value`) if success: copyfileobj(tmp, open(latex_file,"wb"), 1) return success def fix_latex_file(latex_file): documentclass_re = re.compile("(\\\\documentclass\[)(1[012]pt,?)(.+)") tmp = mkstemp() changed = 0 for line in open(latex_file, 'r').readlines(): match = documentclass_re.match(line) if match == None: tmp.write(line) continue changed = 1 tmp.write("%s%s\n" % (match.group(1), match.group(3))) if changed: copyfileobj(tmp, open(latex_file,"wb"), 1) return def convert_to_ppm_format(pngtopnm, basename): png_file_re = re.compile("\.png$") for png_file in glob.glob("%s*.png" % basename): ppm_file = png_file_re.sub(".ppm", png_file) p2p_cmd = '%s "%s"' % (pngtopnm, png_file) p2p_status, p2p_stdout = run_command(p2p_cmd) if p2p_status != None: error("Unable to convert %s to ppm format" % png_file) ppm = open(ppm_file, 'w') ppm.write(p2p_stdout) os.remove(png_file) # Returns a tuple of: # ps_pages: list of page indexes of pages containing PS literals # page_count: total number of pages # pages_parameter: parameter for dvipng to exclude pages with PostScript def find_ps_pages(dvi_file): # latex failed # FIXME: try with pdflatex if not os.path.isfile(dvi_file): error("No DVI output.") # Check for PostScript specials in the dvi, badly supported by dvipng # This is required for correct rendering of PSTricks and TikZ dv2dt = find_exe_or_terminate(["dv2dt"], path) dv2dt_call = '%s "%s"' % (dv2dt, dvi_file) # The output from dv2dt goes to stdout dv2dt_status, dv2dt_output = run_command(dv2dt_call) psliteral_re = re.compile("^special[1-4] [0-9]+ '(\"|ps:)") # Parse the dtl file looking for PostScript specials. # Pages using PostScript specials are recorded in ps_pages and then # used to create a different LaTeX file for processing in legacy mode. page_has_ps = False page_index = 0 ps_pages = [] for line in dv2dt_output.split("\n"): # New page if line.startswith("bop"): page_has_ps = False page_index += 1 # End of page if line.startswith("eop") and page_has_ps: # We save in a list all the PostScript pages ps_pages.append(page_index) if psliteral_re.match(line) != None: # Literal PostScript special detected! page_has_ps = True # Create the -pp parameter for dvipng pages_parameter = "" if len(ps_pages) > 0 and len(ps_pages) < page_index: # Don't process Postscript pages with dvipng by selecting the # wanted pages through the -pp parameter. E.g., dvipng -pp 4-12,14,64 pages_parameter = " -pp " skip = True last = -1 # Use page ranges, as a list of pages could exceed command line # maximum length (especially under Win32) for index in xrange(1, page_index + 1): if (not index in ps_pages) and skip: # We were skipping pages but current page shouldn't be skipped. # Add this page to -pp, it could stay alone or become the # start of a range. pages_parameter += str(index) # Save the starting index to avoid things such as "11-11" last = index # We're not skipping anymore skip = False elif (index in ps_pages) and (not skip): # We weren't skipping but current page should be skipped if last != index - 1: # If the start index of the range is the previous page # then it's not a range pages_parameter += "-" + str(index - 1) # Add a separator pages_parameter += "," # Now we're skipping skip = True # Remove the trailing separator pages_parameter = pages_parameter.rstrip(",") # We've to manage the case in which the last page is closing a range if (not index in ps_pages) and (not skip) and (last != index): pages_parameter += "-" + str(index) return (ps_pages, page_index, pages_parameter) def main(argv): # Parse and manipulate the command line arguments. if len(argv) != 6 and len(argv) != 7: error(usage(argv[0])) output_format = string.lower(argv[1]) dir, latex_file = os.path.split(argv[2]) if len(dir) != 0: os.chdir(dir) dpi = string.atoi(argv[3]) fg_color = make_texcolor(argv[4], False) bg_color = make_texcolor(argv[5], False) fg_color_gr = make_texcolor(argv[4], True) bg_color_gr = make_texcolor(argv[5], True) # External programs used by the script. if len(argv) == 7: latex = argv[6] else: latex = find_exe_or_terminate(["latex", "pplatex", "platex", "latex2e"], path) # Omit font size specification in latex file. fix_latex_file(latex_file) # This can go once dvipng becomes widespread. dvipng = find_exe(["dvipng"], path) if dvipng == None: # The data is input to legacy_conversion in as similar # as possible a manner to that input to the code used in # LyX 1.3.x. vec = [ argv[0], argv[2], argv[3], argv[1], argv[4], argv[5], latex ] return legacy_conversion(vec) pngtopnm = "" if output_format == "ppm": pngtopnm = find_exe_or_terminate(["pngtopnm"], path) # Move color information for PDF into the latex file. if not color_pdf(latex_file, bg_color_gr, fg_color_gr): error("Unable to move color info into the latex file") # Compile the latex file. latex_call = '%s "%s"' % (latex, latex_file) latex_status, latex_stdout = run_command(latex_call) if latex_status != None: warning("%s had problems compiling %s" \ % (os.path.basename(latex), latex_file)) if latex == "xelatex": warning("Using XeTeX") # FIXME: skip unnecessary dvips trial in legacy_conversion_step2 return legacy_conversion_step2(latex_file, dpi, output_format) # The dvi output file name dvi_file = latex_file_re.sub(".dvi", latex_file) # If there's no DVI output, look for PDF and go to legacy or fail if not os.path.isfile(dvi_file): # No DVI, is there a PDF? pdf_file = latex_file_re.sub(".pdf", latex_file) if os.path.isfile(pdf_file): warning("%s produced a PDF output, fallback to legacy." % \ (os.path.basename(latex))) return legacy_conversion_step2(latex_file, dpi, output_format) else: error("No DVI or PDF output. %s failed." \ % (os.path.basename(latex))) # Look for PS literals in DVI pages # ps_pages: list of page indexes of pages containing PS literals # page_count: total number of pages # pages_parameter: parameter for dvipng to exclude pages with PostScript (ps_pages, page_count, pages_parameter) = find_ps_pages(dvi_file) # If all pages need PostScript, directly use the legacy method. if len(ps_pages) == page_count: vec = [argv[0], argv[2], argv[3], argv[1], argv[4], argv[5], latex] return legacy_conversion(vec) # Run the dvi file through dvipng. dvipng_call = '%s -Ttight -depth -height -D %d -fg "%s" -bg "%s" %s "%s"' \ % (dvipng, dpi, fg_color, bg_color, pages_parameter, dvi_file) dvipng_status, dvipng_stdout = run_command(dvipng_call) if dvipng_status != None: warning("%s failed to generate images from %s... fallback to legacy method" \ % (os.path.basename(dvipng), dvi_file)) # FIXME: skip unnecessary dvips trial in legacy_conversion_step2 return legacy_conversion_step2(latex_file, dpi, output_format) # Extract metrics info from dvipng_stdout. metrics_file = latex_file_re.sub(".metrics", latex_file) dvipng_metrics = extract_metrics_info(dvipng_stdout) # If some pages require PostScript pass them to legacy method if len(ps_pages) > 0: # Create a new LaTeX file just for the snippets needing # the legacy method legacy_latex_file = latex_file_re.sub("_legacy.tex", latex_file) filter_pages(latex_file, legacy_latex_file, ps_pages) # Pass the new LaTeX file to the legacy method vec = [ argv[0], latex_file_re.sub("_legacy.tex", argv[2]), \ argv[3], argv[1], argv[4], argv[5], latex ] legacy_metrics = legacy_conversion(vec, True)[1] # Now we need to mix metrics data from dvipng and the legacy method original_bitmap = latex_file_re.sub("%d." + output_format, legacy_latex_file) destination_bitmap = latex_file_re.sub("%d." + output_format, latex_file) # Join metrics from dvipng and legacy, and rename legacy bitmaps join_metrics_and_rename(dvipng_metrics, legacy_metrics, ps_pages, original_bitmap, destination_bitmap) # Convert images to ppm format if necessary. if output_format == "ppm": convert_to_ppm_format(pngtopnm, latex_file_re.sub("", latex_file)) # Actually create the .metrics file write_metrics_info(dvipng_metrics, metrics_file) return (0, dvipng_metrics) if __name__ == "__main__": exit(main(sys.argv)[0])