nixos-artwork.wallpapers: render simple-blue and simple-dark-gray at 5120x2880

[louwers]

The default GNOME wallpapers, simple-dark-gray (dark style) and simple-blue (light style), are 1920x1080 PNGs from 2016. Cinnamon, Pantheon and mint-artwork use them too. On HiDPI screens they get upscaled and look blurry.

NixOS/nixos-artwork is archived, so there's no upstream left to add higher-resolution versions to. Instead, this PR adds small SVG recreations (~5 KB each) next to wallpapers.nix and renders them to 5120x2880 at build time with resvg. That's native on 5K screens and still fewer pixels than GNOME's own 4096x4096 wallpapers.

• Background gradients are fitted to the original PNGs. Downscaled back to 1080p, the new renders match the originals to within 0.35 RMS of one 8-bit level (max 2).
• The snowflake is the official logomark from NixOS/branding (nixos-logomark-white-flat-none). It's inlined unchanged apart from scale and position, at the same size as in the originals. In simple-blue it's knocked out of the white disc with a drop shadow, as in the original.
• License changes from CC0 to CC BY 4.0 because of the logomark. Attribution is in the SVG sources.
• Output paths are unchanged, except the KDE contents/images/<dimensions>.png link, which becomes 5120x2880.png.

Screenshots

1:1 crops at 5K. "Before" is the old 1920x1080 PNG upscaled to 5120x2880, which is what a 5K screen shows.

simple-dark-gray:

simple-blue:

Things done

• Built on platform:
  • x86_64-linux
  • aarch64-linux
  • aarch64-darwin
• Tested, as applicable:
  • NixOS tests in nixos/tests.
  • Package tests at passthru.tests.
  • Tests in lib/tests or pkgs/test for functions and "core" functionality.
• Ran nixpkgs-review on this PR. See nixpkgs-review usage.
• Tested basic functionality of all binary files, usually in ./result/bin/.
• Nixpkgs Release Notes
  • Package update: when the change is major or breaking.
• NixOS Release Notes
  • Module addition: when adding a new NixOS module.
  • Module update: when the change is significant.
• Fits CONTRIBUTING.md, pkgs/README.md, maintainers/README.md and other READMEs.
• Follows the automation/AI policy.

Also built the consumers: gnome.nixos-gsettings-overrides, mint-artwork, pantheon.elementary-default-settings, pantheon.elementary-greeter and sanjuuni.tests.run-on-nixos-artwork. The renders are reproducible (nix-store --realise --check).

AI disclosure: I prepared this with Claude Code (Claude Opus 5.5). It fitted the gradients to the original PNGs, wrote the SVG sources and the Nix change, and made the comparison images.

🤖 Generated with Claude Code

[louwers]

I'm trying to get these into NixOS/branding: NixOS/branding#78

[louwers]

I'm pinging the GNOME team. I am a GNOME user, and I noticed this default wallper has a very low resolution. An alternative to upscaling it might be to remove it from GNOME.

• @bobby285271
• @jtojnar
• @nekowinston
• @theCapypara
• @thunze

[louwers]

It's a bit hard to see if the original has drop shadow or not.

Edit: tweaked the shadow some more. Looks good to me but happy to take comments from people with a better design eye.

[theCapypara]

Thanks! Really cool! I would say we should wait for the branding team's review but then I think this would be a great addition.

Alternatively, since the upstream repo where these originated from is archived and NixOS's KDE installation also just uses the default KDE wallpapers, we could also just ship with one of the default GNOME wallpapers as default. But having a high-res, NixOS branded, dark/light mode aware background would be even better.

[theCapypara]

Oh also, GNOME can render the SVG as-is. In theory there's no need to convert it to a bitmap, however it's blurry...

[louwers]

I agree. Having a NixOS wallpaper available in GNOME is not essential, but it is a really nice touch. Let's see if we can get it in NixOS/branding. Makes more sense to maintain it there than here in Nixpkgs.

Oh also, GNOME can render the SVG as-is. In theory there's no need to convert it to a bitmap, however it's blurry...

I'll try that out! I wonder why it's blurry...

Edit: when I add width="5120" height="2880" to the SVG, I can add it as a wallpaper without bluriness. So that's an option as well. Although ideally GNOME would render SVG screenshots at the resolution of the screen, not at some resolution embedded in the SVG.