[Okular-devel] [PATCH] Fix rendering of DVI documents

[Albert Astals Cid]

A Divendres, 2 d'octubre de 2009, Benoit Jacob va escriure:
> Hi List,
> 
> I noticed that the rendering of DVI documents was broken exactly in
> the same way as what I observed with PDF documents, namely, it used
> auto-hinting which looks especially bad with TeX fonts.
> 
> Attached is a 1-line patch that changes it. I need your permission to
>  commit.
> 
> Screenshots:
> * original :
>  http://picasaweb.google.ca/lh/photo/fry54ANy23UesNpFhbWanA?feat=directlink
>  * fixed :
>  http://picasaweb.google.ca/lh/photo/OjQIZ7Of6wP74k7fKUwXTw?feat=directlink
> 
> Here are some comments before one objects that disabling hinting is
> just a matter of taste, etc.
> 
> First, it's obvious that the "original" screenshot linked above is
> horrible and that the "fixed" is the one that looks good.
> 
> Second, it is a consensus on the Poppler/PDF side that one should use
> no hinting, and then, there's no reason why DVI should be any
> different. To summarize the situation on the PDF side:
> * poppler/cairo (hence Evince) 's code completely disables hinting
> * poppler/splash (hence Okular) 's code _meant_ to completely disable
> hinting (actually only auto-hinting, but in the context of DVI that's
> really the same because almost all DVI files use Type 1 fonts, and
> bytecode only exists in TrueType fonts). It was a clear bug in the
> code, where it was clear that the code didn't do what it intended,
> that resulted in hinted fonts being used.
> 
> Third, the old KDVI used to not do any hinting, I'm completely sure of
> that because I've spent hundreds of hours looking at documents in it.
> I remember distinctly the (imho beautiful) slightly fuzzy look of the
> TeX fonts in it, that is characteristic of non-hinted text, although
> at that time I didn't know about hinting. That said, I used "svn
> annotate" to see who enabled hinting in the C++ code, and it turns out
> to be Stefan Kebekus himself in an old revision (240000-something). I
> am puzzled about that, but I still maintain that KDVI didn't use
> hinting on all the Linux systems that I tried. My best guess is that
> Stefan Kebekus _thought_ that he had enabled hinting but for some
> reason it wasn't used. I haven't investigated further as this is quite
> intricate, and of course I only have Okular's code at hand, I haven't
> looked at the actual KDVI code.
> 
> OK to commit?

No, actually what it is clear that *you* don't like hinting, and you have a 
certain amount of followers, the problem is that typically people that is 
happy with a setting is not much active defending it because they are happy in 
their sofas.

My suggestion is adding a configuration option that lets the user choose 
between "No Hinting", "Hinting" and "Hinting as set in KDE settings". For KDE 
4.3.x we can add it, it set in "Hinting" and the only configuration option 
will be thought non GUI as we can't add translatable texts. For KDE 4.4.x we 
can default to "No Hinting" if others here (basically Pino, Brad, Tokoe) 
agree.

Comments?

Albert

> 
> Benoit
>