Ghostty renders fonts thinner than others

[A7Lavinraj]

font-family = MesloLGM Nerd Font
font-size = 12

theme = tokyonight
shell-integration-features = no-cursor,sudo,no-title
cursor-style = block
adjust-cell-height = 35%

mouse-hide-while-typing = true
mouse-scroll-multiplier = 2

window-padding-balance = true 
window-save-state = always
window-colorspace = "display-p3"
window-decoration = false

keybind = cmd+s>r=reload_config

Expected behaviour

Font should be render in its original thickness

OS information

Arch Linux

[00-kat]

Font should be render in its original thickness

This is a very common issue, and in actuality Ghostty renders it correctly and many terminal emulators render it thicker than they should.

On macOS font-thicken works (see also: #3492 (reply in thread) and #2363 (comment)), but unfortunately on Linux the only way to thicken a font in Ghostty is to use font-style, or font-variation if your font of choice is variable.

You can find out what styles Ghostty can see with ghostty +list-fonts. Example output is:

MesloLGM Nerd Font
  MesloLGM Nerd Font Bold
  MesloLGM Nerd Font Bold Italic
  MesloLGM Nerd Font Italic
  MesloLGM Nerd Font Regular

The styles this font has are Bold, Bold Italic, Italic and Regular. Some fonts often have more styles too (Medium and Light are also common).

Some things to note about font-variation:

1. Make sure to read its docs carefully.
2. Websites such as fontdrop.info also tell you whether a font is variable or not.
3. No patched Nerd Font is variable. Luckily, Ghostty embeds Nerd Font icons, so you don't need to use a patched nerd font¹, and you should rely on font fallback instead² of patching fonts in the first place as patching destroys fonts.
4. The weight axis is typically the one you would want, and it's usually called wght. This can however differ from font to font, so check your font's documentation for instructions.

If you have reason to believe that I am incorrect, and that Ghostty actually doesn't render it at its original thickness, feel free to let me know along with a screenshot for comparision.

Footnotes

1. A known issue is that Ghostty's Nerd Font icons itself come from a patched Nerd Font, which has the issue of having very small icons. See this issue for more information and this discussion for a workaround. ↩

2. On Arch Linux, install the ttf-nerd-fonts-symbols package and Nerd Font symbols will magically work everywhere in your system. ↩

[starcraft66]

This is such a weird hill for ghostty to die on. I will stick to kitty.

[pluiedev]

It's also a weird hill to die on to expect that software with completely different codebases will behave identically. We won't stop you, but the entitlement displayed here is wholly unwarranted.

[starcraft66]

Sorry if I sounded entitled. I just want to say I tried the terminal out, ran into a show-stopper that could not easily be fixed and reverted back to the last thing that worked for myself. I appreciate the help I received here but it just looks like what I'm looking for is not achievable and I am not in a position to contribute this support.

I'm no stranger to opinionated software, kitty's died on a whole bunch of different hills to fix things wrong with terminal emulators that came before it. I'm not a font rendering purist, I literally don't know anything about font rendering but all I want to convey is that I think it would be a desirable feature to be able to have Ghostty display fonts in the same size/thickness/whatever than every other app on my system such as my web browser. Here's a screenshot of Ghostty side-by-side with https://www.programmingfonts.org/#meslo:

[pluiedev]

If you really insist then there are the adjust-* options you can you to finetune the font rendering, but font rendering is much more complex than it looks. I recommend reading https://faultlore.com/blah/text-hates-you/ and see for yourself why you can't just expect font rendering to just "work" and look identically everywhere. If a few pixels being rendered differently is somehow "showstopping" for you, then it's down to you to do the legwork to get it to where you want it.

[00-kat]

And by the way, the reason font-thicken exists on macOS and not Linux is because it's using some Core Text functionality that isn't present in FreeType.