Update octicons and drop old MDI

[Finii]

This can only be done after MDI-old has been dropped

[why]
The octicons got a lot updates.
But they do not have a font anymore.

[how]
Keep our old codepoints constant, but add the new icons thereafter.

Fixes: #490

Requirements / Checklist

• Read the Contributing Guidelines
• Verified the license of any newly added font, glyph, or glyph set

What does this Pull Request (PR) do?

Update the Octicons icons.

If one icon has been dropped (without replacement) re-use its codepoint for a newly added icon.
Append other newly added icons in the end.
Afterwards Octicons will be gapless in F400 - F532 in Nerd Fonts.

Note that we reassign codepoints on patching. The original octicons font has many gaps.
To keep also compatible here the font we create here is a bit ... stranger, with a lot of gaps and some gaps filled.
The methodology seems complicated by the goal is easy: We just want to patch in the icon into Nerd Fonts with the aformentioned codepoints and no additional special rules.

This means for the octicons.ttf
Existing gaps are preserved.
Dropped icons are replaced by newly added ones.
The remainder of new icons is added in the back, which is FAR back, because of the one stray icon the original (old) font had.

How should this be manually tested?

Any background context you can provide?

What are the relevant tickets (if any)?

Screenshots (if appropriate or helpful)

[Finii]

Current output:

Reading mapping file
Found 172 entries
Fetching octicons archive "v18.2.0.tar.gz"


Unpacking octicons archive
Found 574 svgs
Found 308 icons after de-duplicating

Renamed cloud-download -> download
Renamed cloud-upload -> upload
Renamed clippy -> paste
Renamed mail-read -> read
Renamed primitive-dot -> dot-fill
Renamed primitive-square -> square-fill
Renamed settings -> sliders
Renamed dashboard -> meter
Renamed trashcan -> trash
Renamed paintcan -> paintbrush

Missing octoface
Missing keyboard
Missing gist
Missing file-text
Missing file-pdf
Missing jersey
Missing radio-tower
Missing repo-force-push
Missing mail-reply
Missing arrow-small-right
Missing gist-secret
Missing no-newline
Missing arrow-small-up
Missing arrow-small-down
Missing arrow-small-left
Missing file-symlink-directory
Missing circuit-board
Missing watch
Missing text-size
Missing ellipses
Missing plus-small

Found 151 (of 172, missing 21) and new 157

I guess the icons that have been dropped are no problem (but then, what do I know what people use these icons for).
I would just drop them, update the rest, fill in the new gaps with new icons and append the rest of new icons. As they have no codepoints yet we can assign whatever we want.

[Finii]

Octicons have 2 sets of icons, one for 16px and one for 24px scaling. Unfortunately not all icons are available in both sizes.

Whatever, here a comparison of old (left) versus new (right)

The old size seems to be in-between, stroke size wise:

[Finii]

@jef @djensenius What do you think, should we use the 16px or the 24 px octicons?
Given terminal font size 11-15 pt I would guess the 16 px size is better (at the usual 96 dpi)

[Finii]

Fixed copyright issue, force push (sorry for the frequent pushes)

[Finii]

We need to wait until Material Design Icons moved out of the way, because we need their old (dropped with v3.0.0) codepoints partially (F000 - F532).

We just need to do fontforge generate in src/glyphs/octicons/ and commit the changes as commit 2/2.

[jef]

@jef @djensenius What do you think, should we use the 16px or the 24 px octicons?
Given terminal font size 11-15 pt I would guess the 16 px size is better (at the usual 96 dpi)

Great point. IIRC, the 24px octicons have some that aren't available in 16px or vice versa.

If not, then 16px sounds great!

[Finii]

Thanks for the reply. I had the same feeling, so be it. 👍

Great point. IIRC, the 24px octicons have some that aren't available in 16px or vice versa.

Both. The generate script builds a list of all icons, regardless of size. Then later it tries to find that icon in the preferred size and if not available falls back to the other size.

From image above, note 16px icons fill in where not 24px icons are available:

[jef]

Amazing! Nice work and thanks for all the updates :)

[Finii]

Right! 🤦‍♀️

This PR is just preparatory and commit 1/2. Needs to be completed!