They don't make Null Glyphs like they used to!

by Michael S. Kaplan, published on 2006/01/17 04:01 -05:00, original URI: http://blogs.msdn.com/b/michkap/archive/2006/01/17/513635.aspx


Warning #1: if you do not have Palatino Linotype on your machine then most of this post is wasted on you.
Warning #2: If you are not the kind of person entertained by the sorts of things that a person like me would like, it is probably wasted on YOU too.

I think I have talked about the NULL GLYPH before once or twice.

It is basically the character that a font displays if it does not have a character -- the ultimate fallback.

But that does not mean that the people who build fonts can't have a little more fun with it that showing off something a little better than an empty box, right.

So let's take a look at Palatino Linotype for a moment.

From the font's description text:

Palatino Linotype is the definitive new version of Hermann Zapf’s Palatino, which since its design in 1950 has become one of the world's most widely used typefaces. For this new digital version, Professor Zapf has drawn numerous additional characters to include an extensive range of ligatures, numerals, fractions and support for Cyrillic and both monotonic and polytonic Greek. Special care has been taken to enhance the quality of the letterforms when displayed on the computer screen, ensuring that Palatino Linotype is highly legible whether displayed on the screen or in print. This typeface is ideal for use in extended text settings such as books, periodicals and catalogs.

Are you liking it? I am. :-)

It is a wonderful font for for lots of things, including polytonic greek, which is not what this post is about.

Let's look at the NULL GLYPH in this font in the various styles:

REGULAR - 🿾🿾🿾🿾🿾🿾

BOLD - 🿾🿾🿾🿾🿾🿾

ITALIC - 🿾🿾🿾🿾🿾🿾

BOLD ITALIC - 🿾🿾🿾🿾🿾🿾

But just in case anyone has trouble seeing that due to browsers pretending to be smarter than they really are, here is that same text in Wordpad:

Someone was having a little fun with their NULL GLYPH glyphs that day, huh? :-)

(special thanks to Simon Daniels for pointing this one out, and for some of the stories behind the glyphs!)

 

This post brought to you by "🿾" (U+1fffe, a.k.a. something that is not a character in Unicode and is permanately reserved so it will never be one)


# Nick Lamb on 17 Jan 2006 9:27 AM:

This has great Easter Egg value, but it does seem like a mistake to just blindly render these NULL GLYPHs for missing or invalid characters in a system that handles shaping and other complexities already. At best they are misleading to users.

Wouldn't it make more sense to copy Pango's hex boxes or draw a suitably sized dotted box regardless of the provided NULL GLYPH? The latter obeys the principle of least surprise, while the former improves diagnostics (how does a Windows developer figure out which codepoint is being rendered as a mysterious picture of a bird?)

Also, you probably shouldn't use U+1FFFE in documents. As you rightly observe, it's not a Unicode character.

# Markus on 17 Jan 2006 9:39 AM:

This is quite useful - you can determine the font and style from looking at the null glyph. If all fonts supported this feature, it would be much easier to determine what font is actually used (for example, when a html page has a whole list of fonts in its css style, and all you get is a screen shot from a user).

# Mihai on 17 Jan 2006 12:54 PM:

Notepad shows the typical rectangle.

# Michael S. Kaplan on 17 Jan 2006 12:59 PM:

Actaully, if you select the font and style it will show the special null glyph in Notepad....

# Brad Corbin on 17 Jan 2006 1:17 PM:

That's pretty cool.

Is this the only situation you know of where making a character bold or italic will change the glyph entirely? (Instead of simply showing a styled variation of the same character)

# Mihai on 17 Jan 2006 1:30 PM:

"Actaully, if you select the font and style it will show the special null glyph in Notepad...."
I did. Do you want a screen-shoot?

# Michael S. Kaplan on 17 Jan 2006 1:59 PM:

Mihai, I believe you -- maybe you have a different version of the font? I am using version 1.4.

Brad -- usually this would not be expected, but in this case since there are four separate files for the four variants, anything that someone wanted to make different, they could....

# Maurits [MSFT] on 17 Jan 2006 2:45 PM:

I presume the following are all reserved too:
1feff
2fffe
2feff
3fffe
3feff
...
10fffe
10feff

# silverpie on 17 Jan 2006 2:59 PM:

No, only the last two positions (xFFFE and xFFFF) on each astral plane are reserved. The astral projections of the byte order mark are legal characters.

# Dean Harding on 17 Jan 2006 5:13 PM:

Perhaps Mihai has the "Complex Script" support option turned on in Windows? I usually find that such differences in behaviour between different people's copies of Notepad are because one or the other has Complex Script or East Asian Language support turned on.

# Mihai on 17 Jan 2006 7:31 PM:

I think Dean has a point.

It seems to be important what missing character is selected.
I get rectangles in BMP, but the funny glyphs everywhere above.
Two ideas:
- the rectangle is from Palatino in BMP, but the font tables are messed-up for everything above
- Windows does font linking, and the rectangle in BMP is from other font

# Michael S. Kaplan on 17 Jan 2006 11:46 PM:

Nope, the glyphs are definitely in Palatino Linotype -- it is in the BMP that some processes are getting clever....

go to newer or older post, or back to index or month or day