Cabinet setup: boot branding¶

This page is optional. It replaces the generic Ubuntu graphics shown while the cabinet boots with your own artwork. There are three separate things to brand, each with its own mechanism.

What you see	When	Mechanism
Boot splash	Between firmware and the login screen	Plymouth theme
Login background	The brief GDM greeter before autologin	GNOME Shell theme resource
Desktop wallpaper	After login, before an app loads	`gsettings`

You need two images: a square logo for the boot splash (for example boot.png), and a background image for the login screen and desktop (for example bg.png).

1. Boot splash (Plymouth)¶

Create a Plymouth theme that shows your logo centered on black.

Create the directory /usr/share/plymouth/themes/pinball/ and copy boot.png into it. Add pinball.plymouth:

[Plymouth Theme]
Name=Pinball
Description=Custom pinball boot splash
ModuleName=script

[script]
ImageDir=/usr/share/plymouth/themes/pinball
ScriptFile=/usr/share/plymouth/themes/pinball/pinball.script

And pinball.script:

Window.SetBackgroundTopColor(0.0, 0.0, 0.0);
Window.SetBackgroundBottomColor(0.0, 0.0, 0.0);
logo.image  = Image("boot.png");
logo.sprite = Sprite(logo.image);
logo.sprite.SetX(Window.GetWidth()  / 2 - logo.image.GetWidth()  / 2);
logo.sprite.SetY(Window.GetHeight() / 2 - logo.image.GetHeight() / 2);

Activate the theme and rebuild the initramfs:

sudo update-alternatives --install /usr/share/plymouth/themes/default.plymouth \
    default.plymouth /usr/share/plymouth/themes/pinball/pinball.plymouth 200
sudo update-alternatives --set default.plymouth \
    /usr/share/plymouth/themes/pinball/pinball.plymouth
sudo update-initramfs -u

The splash appears on the next boot.

To revert:

sudo update-alternatives --set default.plymouth \
    /usr/share/plymouth/themes/bgrt/bgrt.plymouth
sudo update-initramfs -u

Multi monitor splash

Plymouth draws on whichever output the kernel brings up first. On a multi monitor cabinet the splash may appear on a screen you did not expect. This is cosmetic and lasts only a few seconds.

On Ubuntu, the GDM greeter background is baked into a compiled GNOME Shell theme resource. Changing it means editing that resource.

Install the GLib resource compiler if it is missing:

sudo apt-get install -y libglib2.0-dev-bin

Extract the current resource, patch the CSS, and recompile. The resource lives at /usr/share/gnome-shell/gnome-shell-theme.gresource. Extract every entry, add your bg.png, and append a rule to the greeter stylesheets:

#lockDialogGroup {
    background: #000000 url("resource:///org/gnome/shell/theme/pinball-bg.png");
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}

Rebuild the resource with glib-compile-resources, back up the original to gnome-shell-theme.gresource.orig, and install the new file in its place. The change appears on the next GDM restart or reboot.

To revert, copy the .orig file back over the resource and restart GDM.

3. Desktop wallpaper¶

The wallpaper shown after login is a simple gsettings change. Copy bg.png to a system path and point the background settings at it:

sudo install -m 644 bg.png /usr/share/backgrounds/pinball-bg.png
gsettings set org.gnome.desktop.background picture-uri \
    'file:///usr/share/backgrounds/pinball-bg.png'
gsettings set org.gnome.desktop.background picture-uri-dark \
    'file:///usr/share/backgrounds/pinball-bg.png'
gsettings set org.gnome.desktop.background picture-options 'zoom'

This takes effect immediately.

Next¶

Continue with Install Fliphetic.

Cabinet setup: boot branding¶

1. Boot splash (Plymouth)¶

2. Login background (GDM greeter)¶

3. Desktop wallpaper¶

Next¶