Error in FAQ: Ensuring monospace

[abananabag]

The current answer to how to mark a font as monospaced in the FAQ at https://fontforge.org/docs/faq.html#faq-monospace is outdated and incorrect.

The current (incorrect) answer

How do I mark a font as monospaced?

You don’t. Just insure that all the glyphs in the font have the same width and then FontForge will automatically mark it as monospaced for you. (If you mark it as monospaced incorrectly some rasterizers will give strange results).

If you want to set a font’s panose values yourself (Element->Font Info->OS/2->Panose) then set the Proportion field to Monospaced. This is necessary but not sufficient to mark the font as a whole as monospaced.

If you are unsure whether all the glyphs in your font have the same advance width use Element->Find Problems->Random->Check Advance.

When I say “all glyphs” I really mean all glyphs. Even glyphs which unicode says should be 0 width must have the same width as everything else. MicroSoft suggests that GPOS be used to do accent combination (etc.) and then change the advance width on any marks (accents) to be 0.

Suggested fixes

• Tell people how to ensure that all glyphs in the font have the same width
• Move validation to its own question
• Correct location of menu items for validation
• Provide context for Panose and Zero-width Accents

Suggested new version

How do I mark a font as monospaced?

You don’t. Just insure that all the glyphs in the font have the same width and then FontForge will automatically mark it as monospaced for you. (If you mark it as monospaced incorrectly some rasterizers will give strange results). You can force all glyphs to the same width using the Set Width option. Steps:

1. Make sure Encoding → Compact has a checkmark
2. Press CtrlA (Selects all visible glyphs)
3. Press CtrlShiftL (Opens Metrics → Set Width dialogue)
4. Type in the width you want
5. Click OK

How can I validate my monospaced font without changing it?

If you are unsure whether all the glyphs in your font have the same advance width use Element->Validation->Find Problems->BB->Check Advance.

How can accents be handled in a monospace font?

Even glyphs which unicode says should be 0 width must have the same width as everything else or FontForge will not mark the font as monospaced. MicroSoft suggests that GPOS be used to do accent combination (etc.) and then change the advance width on any marks (accents) to be 0.

What if I know better than FontForge?

If you want to set a font’s panose values yourself use (Element->Font Info->OS/2->Panose) then set the Proportion field to Monospaced. This is necessary but not sufficient to mark the font as a whole as monospaced.

[iorsh]

The new structure looks good. Could you please also address duospaced fonts?

[martinbutt]

The new instructions work

[ChiefMikeK]

fyi: The chart @ https://en.wikipedia.org/wiki/Halfwidth_and_fullwidth_forms#In_Unicode
open type codes would be a good addition ⚓