Tuesday, March 20, 2007

Combining Diacritics vs Precomposed Greek

Well, here I am back at combining diacritics. I may have to change the title of this blog to Suzanne's doodlepad. This is probably not a post of general interest.

To keep a long story short, most polytonic Greek is posted in precomposed form and displays well in IE7. But sometimes Greek text has been produced using combining diacritics. It is a pain because that makes two standards and you can't tell with the naked eye which is which. At least if they display properly you shouldn't be able to. But you can see in the first image how they both look in IE7.

The second image shows both kinds of text in their correct display form in New Athena Unicode and they should look identical.(Are you bored yet?)

The third image is of the two kinds of text displayed by individual glyph.You can see that the combining diacritics text has the ability to decompose, the other kind does not.

There are many pros and cons to all this, but I believe that the usual way to display Greek is by precomposed text. This is the opposite to Hebrew.

As far as Polytonic Greek is concerned, the best resource is Rodney Decker's resources. This page will take you from the age of the dinosaurs up to the present, so I would recommend starting to read this paper on page 10 or 11. The relevant stuff is on pages 14 and 15. Read point 4.3.3 and on footnote 3 on page 15. In fact, if you have to decide in any paper which part to read, I would recommend the footnotes.

In short, most polytonic Greek text is produced in precomposed text. Zhubert produces precomposed as well, so no problem. This is what the MS Greek keyboard does too and probably most of the others. But sometimes there is a bit of the combining diacritics stuff around. For some reason IE does not handle this well, although Firefox, as usual, has no problem. Go figure. BTW, here is a MAC biblioblog.

Anyway, IE7 now does font substitution like Firefox so fonts are not the problem - codepoints are. I use Babelpad to look at things like this along with Babelmap, from Babelstone, along with reading Babelstone Blog, which is a pretty cool blog about Unicode. Except that Andrew is writing about the Morrison Collection right now, so you have to check his archives.
Note: This post has been edited with new images.


Peter Kirk said...

Thanks for waking your blog up again, Suzanne. I'm glad I was subscribed and so found a link.

I know that at one time Microsoft promised that a new version of Uniscribe would display canonically equivalent forms, like precomposed and decomposed Greek, identically. But obviously this version has not been provided with IE7. I think it may be in Windows Vista. So it might be interesting to try this text with Vista.

I would also be interested in seeing how this text displays in Firefox, on Windows XP.

So perhaps you might like to upload your comparative text, as text and not images, to a new posting or to some other website. Then various readers will be able to tell you how this displays on their systems.

By the way, on the subject of Unicode, you have something odd, "mojibake", in the link to "Café Apocalypsis" in your sidebar.

DavidR said...

Fascinating stuff, Suzanne. No, really! :)

You might be interested in this MSN group:


John Hudson is a very talented and knowledgeable font designer. In fact, I think he is based in Vancouver! (Actually, I just checked the Tiro website and it seems he lives on Gabriola Island, British Columbia).

The MSN group has lots of interesting stuff, and John's new SBL Greek font is gorgeous. And available in the Files section of the Group (see this message, though I'm not sure if one needs to be a "member" to see messages).

Where would we be without BabelPad?!


Suzanne McCarthy said...


It looks fine in Firefox on my WinXP system. I meant to say that but forgot.

Andrew West said...

Dear Suzanne, I'm really pleased to see you blogging again, although I wonder why this post is not under you Abecedaria blog?

Thanks for the kind comments on BabelPad -- I'm afraid that I have stopped development on it over the past few months whilst I have been concentrating on other things. I hope to get some time to work on BabelPad over the summer and finally get the new improved version released (unfortunately I have severly broken the code adding in some cool new features, and it will take me some time to sort out the mess I have got into).

Hoping all is well with you and your family.