Re: [hpoj-devel] was: LCD encoding: Please try Dmitry's patch

[Joe P. <joe...@sn...>]

On Monday 12 April 2004 02:16, Dmitry Vukolov wrote:
> Hi Joe,

<...>

> I'm reposting the patch to the mailing list for anyone else who may be
> interested in it. I works without a hitch for iso8859-1 and iso8859-5
> showing all special characters correctly.

OK. I didn't understand that before. You didn't make it clear. If your patch 
fixes all of the problems you were seeing, then the changes I was suggesting 
would not be useful.

I would like to see others try your patch and report their results. I've put 
up a web page containing your patch for download at

http://pages.cthome.net/jsp/prj/xojpanel/xojpanel.html


I've been away from coding (and from xojpanel) for a while, so it will take me 
some time to relearn a bit and to try to understand what your patch will do, 
since I can not see its results on my hardware.

> What bothers me is that the current convertion procedure will probably not
> work for multibyte encodings if HP devices ever make use of them. I would
> appreciate any information and ideas about that.

It seems likely that xojpanel would need some changes. Using QChar for the 
character maps would probably be one of them. 

I don't know if libptal, which xojpanel uses to retrieve the peripherals' LCD 
display strings, can handle multibyte characters.  If it cannot, it would 
need to be hacked. Doing that might be beyond my capability. HP is showing 
little evidence of intention to continue hpoj development.

I can think of a couple of ways that HP could use unicode in future LCD 
displays:

1. Unicode sent to the PC, with software doing character (or even string) 
translations based on a locale setting, then feeding back the translations to 
the LCD display unit.  I think this would only be used when the device is not 
expected to be used in "stand-alone" fashion.

2. Unicode used (or just stored) internally, but making only a subset visible 
to the user, with some way to configure the charset before or (maybe through 
software) after delivery. This would be more suitable for use in stand-alone 
devices. If HP wants to be generous, it could allow the user to configure the 
locale directly on the peripheral.

These are just guesses, though.  It would really be helpful if HP provides 
answers.


> The original idea was that -devenc could be useful not only with cyrillic
> but other non-latin charsets as well. We might make -cyrillic (or -charset
> cyrillic) an alias for -devenc ISO8859-5 for convenience reasons assuming
> that it's the only encoding used by HP for that purpose.

To keep things simple, it might be better to use only '-devenc', as you 
suggested at first. 

-- 
Joe