Re: LANG as an attribute

lilley (lilley@afs.mcc.ac.uk)
Tue, 1 Aug 1995 19:51:03 +0100 (BST)


>
> [Explanation of simple bidi scenario omitted]

Glad you thought it was simple, Jon. It didn't seem too hard to me either.

> OK, now explain how this works with hyphenation and justification --

You correctly note that the example I gave explicitly did not hyphenate
Hebrew. It moved whole words that would not fit onto the next line,
rather than crashing into the margin and inserting a hyphen.It also only
allowed flush left justification (for left-to-right languages) and flush
right justification (for right-to-left languages).

The generated line could of course readilly be right justified or
centred when it was transferred from the layout buffer to the display,
because the algorithm given ensured that the line length was always less
than or equal to the current margin width.

> bearing in mind that the great majority of publishers consider h&j to
> be a more important capability than bidirectional printing.

I am sure they do. The great majority of *readers* on the other hand
consider reading the text at all to be more important than not reading
it (safe in the knowledge they are being spared sub-optimal
hyphenation).

And, Netscape extensions not withstanding the ability to center text is
probably not the most important feature of a browser.

Indeed, such is people's desire to communicate that they have in the
past been willing to jump through hoops - such as actually typing hebrew
letters in reverse to display correctly with a left-to-right formatting
browser - in order to do so.

You did say that DSSSL-Lite would not support mixed left-to-right and
right-to-left text *at all*, did you not? What will it do, then - give
up? Refuse to display the document? Dump core?

What I am saying is, it may be more important to provide limited
functionality than none at all. And just because an expert says that
something is impossible does not mean it cannot be done.

Take myself for example. Someone shows me a bright blue on the screen,
an expensive dye sublimation printer, and asks how that colour can be
printed. I tell them it is impossible, which is perfectly correct as
the colour is outside the gamut of the printer. I have the whole of
colour science to back me up.

A skilled Photoshop operator can however take that image and munge it,
finally outputting separations that give a very nice (although not,
strictly, correct) blue with the same overall feel as the original
on-screen image. Was I incorrect to say the blue was not reproducible?
No. Was I unreasonable to offer no alternative apart from not printing
the image? Yes.

I hope you see the analogy.

-- 
Chris Lilley, Technical Author
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