Rupee Discrepancy

[MAZ06]

Font

NotoSansDevanagari[wdth,wght].ttf
NotoSans[wdth,wght].ttf

Where the font came from, and when

https://github.com/notofonts/devanagari/releases
https://github.com/notofonts/latin-greek-cyrillic/releases

Font Version

Noto Sans Devanagari 2.006
Noto Sans 2.015

OS name and version

Windows 11

Application name and version

Everything

Issue

Similar to my issue here: notofonts/hebrew#54
The rupee in Noto Sans Devanagari is not the same as the rupee in Noto Sans LGC.
Noto Serif seems to be fine.

Could this be an issue for the currency signs in general? Might need to check every currency sign in Noto Sans/Serif LGC to see if they match in their respective language's font.

...Or should they not match?

Character data

₹ U+20B9

Screenshot

Noto Sans LGC on top
Noto Sans Devanagari on bottom

[MAZ06]

I think I've figured out why there's a discrepancy here.

Top is Noto Sans Devanagari
Bottom is the rupee in Noto Sans LGC followed by Noto Sans Devanagari

It appears that the rupee changes height to match the shirorekha (the top line) in Devanagari.

That makes sense, but then that means the numbers are taller than the rupee symbol unless Hindi digits are used:

In Noto Sans LGC, the rupee is the same height as the numbers:

The Noto Sans LGC way of doing it is the way Indian online stores choose to use it when English is selected. For example Amazon India:

But if you select the Hindi language on Amazon, the rupee and numbers align to the shirorekha.

So I think that Noto should follow this pattern and shrink the numbers down to match the shirorekha height.

Strangely though, the rupee symbol in Noto Serif Devanagari does not match the height of the shirorekha and instead is the height of the numbers. Its horizontal lines also don't match the thickness of the shirorekha.

The serif rupee also drifts too far to the right:

If it gets shrunk down along with the numbers, then it should not connect to the line.

[MAZ06]

This may also apply to punctuation. Characters like the question mark or exclamation point may have to be shrunk down to match the shirorekha height. This can be seen on Wikipedia,

[simoncozens]

I agree this would be prettier. But there are four billion Android devices which use Noto Sans Devanagari, many of them low spec devices. Each additional glyph adds byte size to the system image. Noto's goal is to cover the Unicode space in a compact way. Typographical refinement needs to be balanced against that. I don't really want to add a separate set of numerals and punctuation.

[MAZ06]

I would argue that correctness of a script is more important than file size.

And who's speaking of adding a separate set of numerals and punctuation? I would say that the solution here is to remove the Latin versions and replace them with properly sized Devanagari versions.

[simoncozens]

This isn't a question of the script being incorrect. It's about typographic refinement.

And who's speaking of adding a separate set of numerals and punctuation? I would say that the solution here is to remove the Latin versions and replace them with properly sized Devanagari versions.

A key concept in Noto is not to think of each Noto font in isolation. Noto is a family of fonts which works together to provide a font stack to cover all the Unicode codepoints. Noto LGC - with Latin numerals - will be at the bottom of that stack. Noto Devanagari will be higher up in the stack. You are suggesting adding additional Devanagari-specific numerals into the stack.

[MAZ06]

I would still say the numerals/punctuation being the same height as the shirorekha is the correct way and therefore necessary. I should be able to set the language to Hindi and see them properly sized.

As for adding additional glyphs, well, I don't know how low spec these devices you're talking about are, but if they can't handle a few extra glyphs in a font, how do they get anything done in the first place? Unicode adds hundreds of new characters each year. What will happen to these devices when hundreds, if not thousands, of Egyptian or Chinese glyphs get added?

Forgive my ignorance here if I'm missing something, but not adding a couple of glyphs for this reason seems crazy to me.

[MAZ06]

Actually, this might be worse than we thought.

If we judge by Hindi Wikipedia, even the Latin letters are supposed to be the same height as the shirorekha. Example:

Those parentheses hang really low. It looks like they just lowered them instead of resizing them.

It looks like all Latin characters and all punctuation must be aligned to the shirorekha.

This has me wondering if any of this is correct at all. Maybe it should be the opposite? Should Noto Devanagari have been made taller from the start? That would be far easier than shrinking the size of Latin glyphs.

[MAZ06]

This issue would also exist in Noto Bengali. And possibly Gujarati and Gurmukhi.