Why PDF doesn't suck: Guide for LaTeX users By The Writer in Technology Wed Jun 05, 2002 at 03:06:42 PM EST Tags: Software (all tags)
	I thought I knew all there was to know about making PDF's from LaTeX documents. And from the little I do know, I incorrectly concluded that PDF's suck. Well, here's a little eye-opener for you LaTeX fans out there. Some day, you might want to show off LaTeX's superior formatting to people who only know how to view PDF's. And you'll want to know this so that you don't make a fool of yourself (and give them a bad impression of LaTeX).

My First (Mistaken) Impression: PDF sucks I have always been a LaTeX fan ever since I read Leslie Lamport's excellent LaTeX2e book. Emphasizing logical structure rather than visual formatting, it gives great power to the learned user. Its professional quality output is praised by scientific and academic journals all over the world. Well, LaTeX and the underlying TeX engine was developed in the days when PostScript was prevalent. Although its standard output format was DVI, LaTeX documents mostly come as PostScript because that is the most widely-accepted portable printer-friendly format then. And then, along came PDF, the funky new format published by Adobe. My initial experiences with PDF were less than pleasant. Being a LaTeX fan, I tried my hand at creating some PDF's of my LaTeX documents. And guess what -- most of it doesn't show up properly in earlier versions of Acrobat Reader, sometimes it even crashes Acrobat Reader -- and when it does show up correctly (in later versions of Acrobat Reader), the font looks smudged, blurred, pixelated, and just plain unreadable. Furthermore, when I view the original PostScript on GSView, it looks just great. So, my initial reaction was, oh well, PDF can't handle LaTeX's superior formatting. It sucks! And so I thought, until one day, I read this page. The Problem The problem with converting LaTeX-produced PS into PDF, is that the usual program used to perform the initial conversion to PostScript, dvips, simply calls METAFONT (LaTeX's font engine) to rasterize your document's fonts at 300dpi, and then loads the bitmapped results into the PS file. This is known as a Type 3 font, which will also get propagated into the PDF once you convert the PostScript. The problem with Type 3 fonts is that Acrobat Reader does not handle it in a sane way. Unlike other utilities (like GSView, which apparently does a good job at scaling bitmapped fonts), Acrobat Reader was not designed to handle Type 3 fonts well, and it does a minimal, unreadable job at scaling these 300dpi bitmapped fonts (and does so at turtle-crawling speeds, too). This may seem like PDF's fault, but it really isn't. The real problem comes from dvips embedding type 3 fonts in the PostScript. Type 3 fonts aren't particularly great either -- although 300dpi is good for printing on low-end printers, high-end printers with 600dpi resolution won't show any difference with these fonts, because the bitmaps are 300dpi. Type 1 fonts, however, are infinitely scalable fonts; and there are type 1 fonts that you can use with LaTeX! The Solution To create from a LaTeX document a PDF that doesn't suck, what you need is to force dvips to embed Type 1 fonts in the PostScript, and not use any type 3 fonts at all. In order to do this, you need to make sure that you have installed the Type 1 versions of all the fonts that you used in your document. Usually, if you don't mind using Times or one of the other common fonts, all it takes is to do something like \usepackage{times} which will cause LaTeX to typeset your document in the Times font. Since there is only a Type 1 version of Times, dvips will always produce Type 1 fonts in the PostScript. But, if you're like me, and you just must use the default Computer Modern font, you'll need to install the Type 1 version of the CM font. After you install these fonts, you'll need to configure dvips to not use Type 3 fonts. Here are the instructions for doing this. You may also want to consult the documentation for your particular LaTeX distribution -- it may have a slightly different mechanism for adding new Type 1 fonts. Now, run dvips again to produce a PostScript, convert it to PDF using Distiller or any of the other PDF writing tools, and check it out on Acrobat Reader. It should look great now. But... if you're like me (again), you've used some of the more esoteric features of LaTeX, such as diacritics, dotless i's and j's, etc.. If your document uses these symbols, you may find that your PDF still looks butt-ugly. That's because these diacritics are from the EC (European Common) font, and the Type 1 CM fonts don't include these characters. What you need at this point, is to google for "cm-super" (or search for it on CTAN). cm-super is a Type 1 font that includes all the EC characters missing from the default type 1 CM fonts. Install this font, and configure dvips accordingly. Troubleshooting If for some reason your PDF refuses to show up with clear, readable fonts, go to the Info menu in Acrobat Reader, and look up exactly what fonts are being used by your PDF file. You may find that there are still some Type 3 fonts in there. If you're lucky, it may display the name of the font, in which case you should search for the Type 1 versions of the font and install it. But sometimes, Acrobat Reader just uses a non-descript single- or double-letter designation for the font, which is no help in identifying what it is. One way to find out what font it is, if your distribution of LaTeX supports it, is to run dvips -Ppdf. This will force dvips to not use any Type 3 fonts; if there are any missing Type 1 fonts, it will try to invoke METAFONT (mf on the command-line) with a very high magnification factor. Most likely, METAFONT will get confused, and will just print an error message and do nothing. Examine the line that calls mf, and you should see the name of the font -- e.g., ecbx71, etc.. Once you identified the mystery fonts, google for them, and install the appropriate Type 1 fonts. Epilogue Armed with this array of Type 1 fonts, you should now be able to produce PostScript that only contains type 1 fonts. Distiller, or any of the other PDF-writing software, should now be able to create a PDF of your original document that looks decent, and is actually readable on-screen using Acrobat Reader. Now you can show off LaTeX's beautiful output to those PDF-only people!

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Best output file format for LaTeX documents: PS (long live PostScript!) 30% DVI 14% PDF 38% plain text 7% plain TeX... 4% MS Word document 5% Votes: 70 Results | Other Polls

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Google this page Type 1 version of the CM font. instructio ns for doing this google CTAN Also by The Writer