Subscript and Superscript in FontLab Metrics and Dimensions window

jshen
15.May.2008 2.07pm
jshen's picture

Can anyone explain what these settings in the Font Info window control and how you determine what settings to use, especially if your font contains superscripts and subscript numerals? Neither the Fl manual nor Learn FL Fast addresses this.
Thanks,
Juliet



Theunis de Jong
15.May.2008 4.08pm
Theunis de Jong's picture

Do you mean the numbers in Font Info -> Font Dimensions -> Subscript and Superscript?
These don’t have any relation to the actual glyphs in your font, they are merely suggestions for programs that synthesize (i.e. scale and position) super- and subscripts. And it’s not even guaranteed all programs use these; InDesign, for example, uses its own default settings.
The same goes for underline and strikeout thickness and position.

Note that these numbers are in design values; for a typical Type 1 font in 1000ths, for a TTF in 2048ths. Typically, they are in percents in any other program (hint towards FL).


jshen
15.May.2008 5.16pm
jshen's picture

Yes I do mean the settings in the Font Info > Metrics and Dimensions > Subscript and Superscript window.

I understand they have nothing to do with your glyphs and they may not be accessed by a lot of apps, but since they are in the font info I was just wondering if anyone has ever deliberately changed the values they found there, deleted all the values, or made an effort to put values that would be appropriate if they were accessed? Is it safe to ignore this window? Is that what most designers do?


twardoch
18.May.2008 5.00am
twardoch's picture

Microsoft Word for Windows uses these, so it does make sense to put reasonable values in there. Ideally, the values should correspond to the actual sizes of your “sups” and “sinf” glyphs.

Adam


Theunis de Jong
18.May.2008 5.10am
Theunis de Jong's picture

.. so it’s up to the designer. Thanks, Adam, sound advice.

Given that, would you consider ID at fault? They could have added an “auto” checkbox to the superscript/subscript preferences.


jshen
19.May.2008 11.43am
jshen's picture

Adam,
From what point in the glyph window are xpos and ypos positions measured (left side-bearing and baseline)?
Thanks,
Juliet


k.l.
19.May.2008 12.47pm
k.l.'s picture

Given that, would you consider ID at fault?

ID is OpenType-savvy which means that it gives access to especially designed superior/inferior numerals and (depends on the font) letters. Not only scaled, but also slightly bolder than merely scaled ones so they better fit with normal-sized letters.

From what point in the glyph window are xpos and ypos positions measured

The official description is at http://www.microsoft.com/OpenType/OTSpec/os2.htm


twardoch
21.May.2008 6.04am
twardoch's picture

> From what point in the glyph window
> are xpos and ypos positions measured

From the 0,0 point, just like any other coordinate.

A.


k.l.
21.May.2008 8.28am
k.l.'s picture

Ups, got the question completely wrong ...