Ted wrote, quoting me:
In many cases, xhtml is a better format for document interchange.
Horses for courses, of course; and where xhtml may be useful, XML may be even better. If you're not fussed about how the person at the other end will format the layout, then it's probably OK (depending on what kind of document it is). If what you want them to see is precisely what you see, then it can get very hairy.
As this thread has shown, I think, PDF is also about as hairy because of the fragmentation of the standard by its owner. Files look different in each viewer and some viewers don't like some files. At least with xhtml+css, you can specify as much formatting as the viewer supports, but they can nearly always see it all, even if misformatted. With PDF, if the viewer doesn't support all the formatting, you're left with some unhelpful error message and no way to recover the information.
On 07-Feb-02 MJ Ray wrote:
Ted wrote, quoting me:
If what you want them to see is precisely what you see, then it can get very hairy [using xhtml/xml].
As this thread has shown, I think, PDF is also about as hairy because of the fragmentation of the standard by its owner. Files look different in each viewer and some viewers don't like some files. At least with xhtml+css, you can specify as much formatting as the viewer supports, but they can nearly always see it all, even if misformatted. With PDF, if the viewer doesn't support all the formatting, you're left with some unhelpful error message and no way to recover the information.
I think there is something of "cross-purposes" here!
In my experience (and I have sent and received very many PDF files, including many uploaded from the Web), I have almost _never_ had a problem with viewing them in Acrobat Reader and even then the problem has been minor. Exactly ditto for the many people to whom I send files, who also view them with Acrobat reader (often under Windows). And many of the files I send are demanding. I have _never_ been told that it doesn't work.
Therefore I don't recognise the situation Mark is describing, at any rate for the Reader viewer. If Mark is referring to other viewers, with which PDF is "hairy", gives "unhelpful error messages", etc., then my first reaction is "don't use that viewer".
There is a possible problem with fonts on non-Reader viewers, in that you can rely on Reader knowing all about the standard Adobe set of PS fonts, while non-Reader viewers (which may include xpdf) may not be fully aware unless the repertoire which can be found in ghostscript is properly consulted. (I think that nowadays the gs version of the Adobe font metrics is pretty close to Adobe's, if not identical. 'Twas not always thus.) If your document uses other fonts, then it is up to the software creating the PS/PDF to make sure that the full font descriptions are embedded in the file to start with.
There cab also be potential problems with the conversion from PS to PDF. Recent versions of ghostscript (and therefore, with it, ps2pdf) are much sounder than they used to be, and also support much more of the PDF standard (including pdfmarks). In difficult cases I may fall back on Frank Siegert's "Pstill" which, while more difficult to install and set up and while tending to produce much bigger files because it embeds everything unless made not to, nevertheless does a fine job. See:
Mind you, I also hear from some people that problems can arise because (Adobe have announced that) the Acrobat tools need not support anything generated by non-Adobe software, including an apparent case of not touching PDF generated from ghostscript-7.3. There is however PDF/X, the ANSI standard subset of PDF; it's not clear whether Acrobat must support this, from any source, whatever it does with non-PDF/X.
But, in summary again, provided you use Acrobat Reader, in my belief here are no major problems with PDF unless it has been badly generated; with the caveat about Adobe software (not sure if this applies to Reader) possibly getting huffy about non-Adobe source.
Cheers, Ted.
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