Styles

As stated in the repository’s README, Regolith styles are a convention by which a set of files which define key/value pairs are loaded into memory and can be queried by xrdb or xrescat. Xresources employs the C preprocessor to allow for behaviors such as including more files, defining constants and conditional expressions. In Regolith, only two preprocessor directives are used: #include and #define. #include statements are used to reference other files. Collections of files called looks were covered in the previous section of this guide. #define statements simply allow for a symbolic value to be replaced by a literal value, like defining a variable.

Defines

To maximize the re-use of theme information in Regolith, Xresources are divided into two categories of files: definition files and application files. The definition files make heavy use of the define directive. They essentially bind an abstract key, such as “blue” or “terminal font” to a literal value, such as #0000FF or Source Code Pro Medium. In making changes to files, it’s expected that these defines will change. The user may wish to specify a different icon set, or typeface, and would do so by modifying or creating a new definition file. Once this file is created, it needs to be referenced by a top-level Xresources file in ~/.Xresources-regolith.

Application Xresources files

As mentioned previously, a number of Xresources are present in /etc/regolith/styles, including those for specific applications such as st or i3-wm. Opening these files will show a mapping of the abstract keys provided by the defines files to application specific keys. In this way, the general description of the look can be mapped to any UI component or application that can read from Xresources.

Loading Order

The /usr/bin/regolith-session-init script will check for the first Xresources file it finds in the following order:

1. ~/.Xresources-regolith
2. /etc/regolith/styles/root

In addition to a Regolith Xresources file, ~/.Xresources will also be loaded if it exists upon session start.

After loading a root Xresources file, the session init script then merges any entries found in the ~/.config/regolith/Xresources file. This file provides a quick way of simply overriding a few values without having to copy the entire set of resource definitions.

Reloading Xresources

The regolith-look command can be used to reload all Xresources entries as they are otherwise only loaded upon session initialization:

$ regolith-look refresh

Alternatively, the xrdb command can be used to refresh specific Xresources files after they have changed. For example, to reload the user Xresources file run:

$ xrdb -merge ~/.Xresources-regolith

Verification

You can test that a change has been made to your Xresources file by querying it from the command line. If a change was made to key foo.bar then the following command will return it’s current value, or empty if unset:

$ xrescat foo.bar empty