Add 4k png and xcf of simple blue

[khinch]

No description provided.

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/is-there-a-4k-version-of-the-simple-blue-wallpaper/33970/9

[TLATER]

Just to be clear, original work was by @ericsagnes, who published it under CC0 as I understand it, I just imitated it to be as close to the original as I could manage.

@ericsagnes if you stumble across this and still have the gradient settings from the original, a closer match would be cool ;)

[nikableh]

This is nice! It would be awesome if you had also recreated a 4K nix-wallpaper-simple-dark-gray.png. Then it would be possible to use them as a light and dark variants (GNOME supports changing wallpapers depending on the system theme)

To be fair, it would be even better if this was an SVG so that people could export it into any size. And GNOME can even directly use SVG files as wallpapers.

[khinch]

This is nice! It would be awesome if you had also recreated a 4K nix-wallpaper-simple-dark-gray.png. Then it would be possible to use them as a light and dark variants (GNOME supports changing wallpapers depending on the system theme)

To be fair, it would be even better if this was an SVG so that people could export it into any size. And GNOME can even directly use SVG files as wallpapers.

Yes, if I had more skill with Gimp I could have managed the layers so that the colour could be more easily changed to anything else. The XCF is attached so it could be tweaked, but looking at it now the layers aren't set up to easily change the colours. There's more detail in the thread linked above.

Also, I should have included a description with the PR to communicate this a bit better.