Install by copying the shelby directory to /usr/share/plymouth/themes. You can get this directory on its own from the releases (just extract the tarball).
Follow your distribution's instructions for changing the theme. On Arch you need to:
- change the Theme option in /etc/plymouth/plymouthd.conf to shelby
- run plymouth-set-default-theme -R shelby as root. For me, this generates a ton of warnings about UTF-8 filenames, but it does end up working.
It's probably the same on other distros, but it's worth checking.

Files

spinny.blend is a Blender project containing the 3D model set up to spin around in a loop
frames contains 4K (in retrospect, overkill) renders of the blåhaj in various orientations
shelby contains the theme itself, mostly copied from the default spinner theme except for the car images and name/description
scripts contains a few scripts I used to generate the final images. Generally the workflow is to run ./scripts/crop.sh and then ./scripts/fade.sh from this repository. See comments in each script for more on what they do. You need Python 3, ffmpeg, GNU parallel, and optionally optipng (comment out the lines that call it if you don't want to use it).