Fontaine (fontaine.el)

Set Emacs font configurations using presets

This manual, written by Protesilaos Stavrou, describes the customization options for fontaine (or fontaine.el), and provides every other piece of information pertinent to it.

The documentation furnished herein corresponds to stable version 0.4.0, released on 2022-09-07. Any reference to a newer feature which does not yet form part of the latest tagged commit, is explicitly marked as such.

Current development target is 0.5.0-dev.

1. COPYING

Copyright (C) 2022 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual,” and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License.”

(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.”

2. Overview

Fontaine lets the user specify presets of font configurations and set them on demand on graphical Emacs frames. The user option fontaine-presets holds all such presets.

Presets consist of a list of properties that govern the family, weight, and height of the faces default, fixed-pitch, fixed-pitch-serif, variable-pitch, bold, and italic. Each preset is identified by a user-defined symbol as the car of a property list. It looks like this (check the default value of fontaine-presets for how everything is pieced together):

(regular
 ;; I keep all properties for didactic purposes, but most can be
 ;; omitted.
 :default-family "Monospace"
 :default-weight regular
 :default-height 100
 :fixed-pitch-family nil ; falls back to :default-family
 :fixed-pitch-weight nil ; falls back to :default-weight
 :fixed-pitch-height 1.0
 :fixed-pitch-serif-family nil ; falls back to :default-family
 :fixed-pitch-serif-weight nil ; falls back to :default-weight
 :fixed-pitch-serif-height 1.0
 :variable-pitch-family "Sans"
 :variable-pitch-weight nil
 :variable-pitch-height 1.0
 :bold-family nil ; use whatever the underlying face has
 :bold-weight bold
 :italic-family nil
 :italic-slant italic
 :line-spacing nil)

The doc string of fontaine-presets explains all properties in detail and documents some important caveats or information about font settings in Emacs.

Shared and implicit fallback values for presets.

The command fontaine-set-preset applies the desired preset. If there is only one available, it implements it outright. Otherwise it produces a minibuffer prompt with completion among the available presets. When called from Lisp, the fontaine-set-preset requires a PRESET argument, such as:

(fontaine-set-preset 'regular)

The default behaviour of fontaine-set-preset is to change fonts across all graphical frames. The user can, however, limit the changes to a given frame. For interactive use, this is done by invoking the command with a universal prefix argument (C-u by default), which changes fonts only in the current frame. When used in Lisp, the FRAME argument can be a frame object (satisfies framep) or a non-nil value: the former applies the effects to the given object, while the latter means the current frame and thus is the same as interactively supplying the prefix argument.

The command fontaine-set-face-font prompts with completion for a face and then asks the user to specify the value of the relevant properties. Preferred font families can be defined in the user option fontaine-font-families, otherwise Fontaine will try to find suitable options among the fonts installed on the system (not always reliable, depending on the Emacs build and environment it runs in). The list of faces to choose from is the same as that implied by the fontaine-presets. Properties to change and their respective values will depend on the face. For example, the default face requires a natural number for its height attribute, whereas every other face needs a floating point (understood as a multiple of the default height). This command is for interactive use only and is supposed to be used for previewing certain styles before eventually codifying them as presets.

Changing the bold and italic faces only has a noticeable effect if the underlying theme does not hardcode a weight and slant but inherits from those faces instead (e.g. the modus-themes).

The fontaine-set-face-font also accepts an optional FRAME argument, which is the same as what was described above for fontaine-set-preset.

The latest value of fontaine-set-preset is stored in a file whose location is defined in fontaine-latest-state-file (normally part of the .emacs.d directory). Saving is done by the function fontaine-store-latest-preset, which should be assigned to a hook (e.g. kill-emacs-hook). To restore that value, the user can call the function fontaine-restore-latest-preset (such as by adding it to their init file).

For users of the no-littering package, fontaine-latest-state-file is not stored in their .emacs.d, but in a standard directory instead: https://github.com/emacscollective/no-littering.

As for the name of this package, it is the French word for “fountain” which, in turn, is what the font or source is. However, I will not blame you if you can only interpret it as a descriptive acronym: FONTs Are Irrelevant in Non-graphical Emacs (because that is actually true).

2.1. Shared and implicit fallback values for presets

The user option fontaine-presets may look like this (though check its default value before you make any edits):

(setq fontaine-presets
      '((regular
         :default-family "Hack"
         :default-weight normal
         :default-height 100
         :fixed-pitch-family "Fira Code"
         :fixed-pitch-weight nil ; falls back to :default-weight
         :fixed-pitch-height 1.0
         :variable-pitch-family "Noto Sans"
         :variable-pitch-weight normal
         :variable-pitch-height 1.0
         :bold-family nil ; use whatever the underlying face has
         :bold-weight bold
         :italic-family "Source Code Pro"
         :italic-slant italic
         :line-spacing 1)
        (large
         :default-family "Iosevka"
         :default-weight normal
         :default-height 150
         :fixed-pitch-family nil ; falls back to :default-family
         :fixed-pitch-weight nil ; falls back to :default-weight
         :fixed-pitch-height 1.0
         :variable-pitch-family "FiraGO"
         :variable-pitch-weight normal
         :variable-pitch-height 1.05
         :bold-family nil ; use whatever the underlying face has
         :bold-weight bold
         :italic-family nil ; use whatever the underlying face has
         :italic-slant italic
         :line-spacing 1)))

Notice that not all properties need to be specified, as they have reasonable fallback values. The above can be written thus (removed lines are left empty for didactic purposes):

(setq fontaine-presets
      '((regular
         :default-family "Hack"

         :default-height 100
         :fixed-pitch-family "Fira Code"


         :variable-pitch-family "Noto Sans"




         :italic-family "Source Code Pro"

         :line-spacing 1)
        (large
         :default-family "Iosevka"

         :default-height 150



         :variable-pitch-family "FiraGO"






         :line-spacing 1)))

Without the empty lines, we have this, which yields the same results as the first example:

(setq fontaine-presets
      '((regular
         :default-family "Hack"
         :default-height 100
         :fixed-pitch-family "Fira Code"
         :variable-pitch-family "Noto Sans"
         :italic-family "Source Code Pro"
         :line-spacing 1)
        (large
         :default-family "Iosevka"
         :default-height 150
         :variable-pitch-family "FiraGO"
         :line-spacing 1)))

We call the properties of the removed lines “implicit fallback values”.

This already shows us that the value of fontaine-presets does not need to be extensive. To further improve its conciseness, it accepts a special preset that provides a list of “shared fallback properties”: the t preset. This one is used to define properties that are common to multiple presets, such as the regular and large we have illustrated thus far. Here is how verbose presets can be expressed succinctly:

;; Notice the duplication of properties and how we will avoid it.
(setq fontaine-presets
      '((regular
         :default-family "Iosevka Comfy"
         :default-weight normal
         :default-height 100
         :fixed-pitch-family nil ; falls back to :default-family
         :fixed-pitch-weight nil ; falls back to :default-weight
         :fixed-pitch-height 1.0
         :variable-pitch-family "FiraGO"
         :variable-pitch-weight normal
         :variable-pitch-height 1.05
         :bold-family nil ; use whatever the underlying face has
         :bold-weight bold
         :italic-family nil
         :italic-slant italic
         :line-spacing nil)
        (medium
         :default-family "Iosevka Comfy"
         :default-weight semilight
         :default-height 140
         :fixed-pitch-family nil ; falls back to :default-family
         :fixed-pitch-weight nil ; falls back to :default-weight
         :fixed-pitch-height 1.0
         :variable-pitch-family "FiraGO"
         :variable-pitch-weight normal
         :variable-pitch-height 1.05
         :bold-family nil ; use whatever the underlying face has
         :bold-weight bold
         :italic-family nil
         :italic-slant italic
         :line-spacing nil)
        (large
         :default-family "Iosevka Comfy"
         :default-weight semilight
         :default-height 180
         :fixed-pitch-family nil ; falls back to :default-family
         :fixed-pitch-weight nil ; falls back to :default-weight
         :fixed-pitch-height 1.0
         :variable-pitch-family "FiraGO"
         :variable-pitch-weight normal
         :variable-pitch-height 1.05
         :bold-family nil ; use whatever the underlying face has
         :bold-weight extrabold
         :italic-family nil
         :italic-slant italic
         :line-spacing nil)))

(setq fontaine-presets
      '((regular
         :default-height 100)
        (medium
         :default-weight semilight
         :default-height 140)
        (large
         :default-weight semilight
         :default-height 180
         :bold-weight extrabold)
        (t ; our shared fallback properties
         :default-family "Iosevka Comfy"
         :default-weight normal
         ;; :default-height 100
         :fixed-pitch-family nil ; falls back to :default-family
         :fixed-pitch-weight nil ; falls back to :default-weight
         :fixed-pitch-height 1.0
         :variable-pitch-family "FiraGO"
         :variable-pitch-weight normal
         :variable-pitch-height 1.05
         :bold-family nil ; use whatever the underlying face has
         :bold-weight bold
         :italic-family nil
         :italic-slant italic
         :line-spacing nil)))

The t preset does not need to explicitly cover all properties. It can rely on the aforementioned “implicit fallback values” to further reduce its verbosity (though the user can always write all properties if they intend to change their values). We then have this transformation:

;; The verbose form
(setq fontaine-presets
      '((regular
         :default-height 100)
        (medium
         :default-weight semilight
         :default-height 140)
        (large
         :default-weight semilight
         :default-height 180
         :bold-weight extrabold)
        (t ; our shared fallback properties
         :default-family "Iosevka Comfy"
         :default-weight normal
         ;; :default-height 100
         :fixed-pitch-family nil ; falls back to :default-family
         :fixed-pitch-weight nil ; falls back to :default-weight
         :fixed-pitch-height 1.0
         :variable-pitch-family "FiraGO"
         :variable-pitch-weight normal
         :variable-pitch-height 1.05
         :bold-family nil ; use whatever the underlying face has
         :bold-weight bold
         :italic-family nil
         :italic-slant italic
         :line-spacing nil)))

;; The concise one which relies on "implicit fallback values"
(setq fontaine-presets
      '((regular
         :default-height 100)
        (medium
         :default-weight semilight
         :default-height 140)
        (large
         :default-weight semilight
         :default-height 180
         :bold-weight extrabold)
        (t ; our shared fallback properties
         :default-family "Iosevka Comfy"
         :default-weight normal
         :variable-pitch-family "FiraGO"
         :variable-pitch-height 1.05)))

3. Installation

3.1. GNU ELPA package

The package is available as fontaine. Simply do:

M-x package-refresh-contents
M-x package-install

And search for it.

GNU ELPA provides the latest stable release. Those who prefer to follow the development process in order to report bugs or suggest changes, can use the version of the package from the GNU-devel ELPA archive. Read: https://protesilaos.com/codelog/2022-05-13-emacs-elpa-devel/.

3.2. Manual installation

Assuming your Emacs files are found in ~/.emacs.d/, execute the following commands in a shell prompt:

cd ~/.emacs.d

# Create a directory for manually-installed packages
mkdir manual-packages

# Go to the new directory
cd manual-packages

# Clone this repo, naming it "fontaine"
git clone https://git.sr.ht/~protesilaos/fontaine fontaine

Finally, in your init.el (or equivalent) evaluate this:

;; Make Elisp files in that directory available to the user.
(add-to-list 'load-path "~/.emacs.d/manual-packages/fontaine")

Everything is in place to set up the package.

4. Sample configuration

Remember to read the relevant doc strings.

(require 'fontaine)

(setq fontaine-latest-state-file
      (locate-user-emacs-file "fontaine-latest-state.eld"))

;; Iosevka Comfy is my highly customised build of Iosevka with
;; monospaced and duospaced (quasi-proportional) variants as well as
;; support or no support for ligatures:
;; <https://git.sr.ht/~protesilaos/iosevka-comfy>.
;;
;; Iosevka Comfy            == monospaced, supports ligatures
;; Iosevka Comfy Fixed      == monospaced, no ligatures
;; Iosevka Comfy Duo        == quasi-proportional, supports ligatures
;; Iosevka Comfy Wide       == like Iosevka Comfy, but wider
;; Iosevka Comfy Wide Fixed == like Iosevka Comfy Fixed, but wider
(setq fontaine-presets
      '((tiny
         :default-family "Iosevka Comfy Wide Fixed"
         :default-height 70)
        (small
         :default-family "Iosevka Comfy Fixed"
         :default-height 90)
        (regular
         :default-height 100)
        (medium
         :default-height 110)
        (large
         :default-weight semilight
         :default-height 140
         :bold-weight extrabold)
        (presentation
         :default-weight semilight
         :default-height 170
         :bold-weight extrabold)
        (jumbo
         :default-weight semilight
         :default-height 220
         :bold-weight extrabold)
        (t
         ;; I keep all properties for didactic purposes, but most can be
         ;; omitted.  See the fontaine manual for the technicalities:
         ;; <https://protesilaos.com/emacs/fontaine>.
         :default-family "Iosevka Comfy"
         :default-weight regular
         :default-height 100
         :fixed-pitch-family nil ; falls back to :default-family
         :fixed-pitch-weight nil ; falls back to :default-weight
         :fixed-pitch-height 1.0
         :fixed-pitch-serif-family nil ; falls back to :default-family
         :fixed-pitch-serif-weight nil ; falls back to :default-weight
         :fixed-pitch-serif-height 1.0
         :variable-pitch-family "Iosevka Comfy Duo"
         :variable-pitch-weight nil
         :variable-pitch-height 1.0
         :bold-family nil ; use whatever the underlying face has
         :bold-weight bold
         :italic-family nil
         :italic-slant italic
         :line-spacing nil)))

;; Recover last preset or fall back to desired style from
;; `fontaine-presets'.
(fontaine-set-preset (or (fontaine-restore-latest-preset) 'regular))

;; The other side of `fontaine-restore-latest-preset'.
(add-hook 'kill-emacs-hook #'fontaine-store-latest-preset)

;; fontaine does not define any key bindings.  This is just a sample that
;; respects the key binding conventions.  Evaluate:
;;
;;     (info "(elisp) Key Binding Conventions")
(define-key global-map (kbd "C-c f") #'fontaine-set-preset)
(define-key global-map (kbd "C-c F") #'fontaine-set-face-font)

4.1. Persist font configurations on theme switch

Themes re-apply face definitions when they are loaded. This is necessary to render the theme. For certain faces, such as bold and italic, it means that their font family may be reset (depending on the particularities of the theme).

To avoid such a problem, we can arrange to restore the current font preset which was applied by fontaine-set-preset. Fontaine provides the command fontaine-apply-current-preset. It can either be called interactively after loading a theme or be assigned to a hook that is ran at the post load-theme phase.

Some themes that provide a hook are the modus-themes and ef-themes (both by Protesilaos), so we can use something like:

(add-hook 'modus-themes-after-load-theme-hook #'fontaine-apply-current-preset))

If both packages are used, we can either write two lines of add-hook or do this:

;; Persist font configurations while switching themes (doing it with
;; my `modus-themes' and `ef-themes' via the hooks they provide).
(dolist (hook '(modus-themes-after-load-theme-hook ef-themes-post-load-hook))
  (add-hook hook #'fontaine-apply-current-preset))

Themes must specify a hook that is called by their relevant commands at the post-theme-load phase. This can also be done in a theme-agnostic way:

;; Set up the `after-enable-theme-hook'
(defvar after-enable-theme-hook nil
  "Normal hook run after enabling a theme.")

(defun run-after-enable-theme-hook (&rest _args)
  "Run `after-enable-theme-hook'."
  (run-hooks 'after-enable-theme-hook))

(advice-add 'enable-theme :after #'run-after-enable-theme-hook)

And then simply use that hook:

(add-hook 'after-enable-theme-hook #'fontaine-apply-current-preset)

5. Acknowledgements

Fontaine is meant to be a collective effort. Every bit of help matters.

Author/maintainer
Protesilaos Stavrou.
Contributions to the code or manual
Christopher League, Eli Zaretskii, Florent Teissier, Terry F. Torrey.
Ideas and user feedback
Ted Reed.

6. GNU Free Documentation License


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K. For any section Entitled "Acknowledgements" or "Dedications",
   Preserve the Title of the section, and preserve in the section all
   the substance and tone of each of the contributor acknowledgements
   and/or dedications given therein.
L. Preserve all the Invariant Sections of the Document,
   unaltered in their text and in their titles.  Section numbers
   or the equivalent are not considered part of the section titles.
M. Delete any section Entitled "Endorsements".  Such a section
   may not be included in the Modified Version.
N. Do not retitle any existing section to be Entitled "Endorsements"
   or to conflict in title with any Invariant Section.
O. Preserve any Warranty Disclaimers.

If the Modified Version includes new front-matter sections or
appendices that qualify as Secondary Sections and contain no material
copied from the Document, you may at your option designate some or all
of these sections as invariant.  To do this, add their titles to the
list of Invariant Sections in the Modified Version's license notice.
These titles must be distinct from any other section titles.

You may add a section Entitled "Endorsements", provided it contains
nothing but endorsements of your Modified Version by various
parties--for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition of a
standard.

You may add a passage of up to five words as a Front-Cover Text, and a
passage of up to 25 words as a Back-Cover Text, to the end of the list
of Cover Texts in the Modified Version.  Only one passage of
Front-Cover Text and one of Back-Cover Text may be added by (or
through arrangements made by) any one entity.  If the Document already
includes a cover text for the same cover, previously added by you or
by arrangement made by the same entity you are acting on behalf of,
you may not add another; but you may replace the old one, on explicit
permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License
give permission to use their names for publicity for or to assert or
imply endorsement of any Modified Version.


5. COMBINING DOCUMENTS

You may combine the Document with other documents released under this
License, under the terms defined in section 4 above for modified
versions, provided that you include in the combination all of the
Invariant Sections of all of the original documents, unmodified, and
list them all as Invariant Sections of your combined work in its
license notice, and that you preserve all their Warranty Disclaimers.

The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy.  If there are multiple Invariant Sections with the same name but
different contents, make the title of each such section unique by
adding at the end of it, in parentheses, the name of the original
author or publisher of that section if known, or else a unique number.
Make the same adjustment to the section titles in the list of
Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled "History"
in the various original documents, forming one section Entitled
"History"; likewise combine any sections Entitled "Acknowledgements",
and any sections Entitled "Dedications".  You must delete all sections
Entitled "Endorsements".


6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other
documents released under this License, and replace the individual
copies of this License in the various documents with a single copy
that is included in the collection, provided that you follow the rules
of this License for verbatim copying of each of the documents in all
other respects.

You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert a
copy of this License into the extracted document, and follow this
License in all other respects regarding verbatim copying of that
document.


7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate
and independent documents or works, in or on a volume of a storage or
distribution medium, is called an "aggregate" if the copyright
resulting from the compilation is not used to limit the legal rights
of the compilation's users beyond what the individual works permit.
When the Document is included in an aggregate, this License does not
apply to the other works in the aggregate which are not themselves
derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one half of
the entire aggregate, the Document's Cover Texts may be placed on
covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic form.
Otherwise they must appear on printed covers that bracket the whole
aggregate.


8. TRANSLATION

Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section 4.
Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections.  You may include a
translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also include
the original English version of this License and the original versions
of those notices and disclaimers.  In case of a disagreement between
the translation and the original version of this License or a notice
or disclaimer, the original version will prevail.

If a section in the Document is Entitled "Acknowledgements",
"Dedications", or "History", the requirement (section 4) to Preserve
its Title (section 1) will typically require changing the actual
title.


9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document
except as expressly provided under this License.  Any attempt
otherwise to copy, modify, sublicense, or distribute it is void, and
will automatically terminate your rights under this License.

However, if you cease all violation of this License, then your license
from a particular copyright holder is reinstated (a) provisionally,
unless and until the copyright holder explicitly and finally
terminates your license, and (b) permanently, if the copyright holder
fails to notify you of the violation by some reasonable means prior to
60 days after the cessation.

Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from that
copyright holder, and you cure the violation prior to 30 days after
your receipt of the notice.

Termination of your rights under this section does not terminate the
licenses of parties who have received copies or rights from you under
this License.  If your rights have been terminated and not permanently
reinstated, receipt of a copy of some or all of the same material does
not give you any rights to use it.


10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the
GNU Free Documentation License from time to time.  Such new versions
will be similar in spirit to the present version, but may differ in
detail to address new problems or concerns.  See
https://www.gnu.org/licenses/.

Each version of the License is given a distinguishing version number.
If the Document specifies that a particular numbered version of this
License "or any later version" applies to it, you have the option of
following the terms and conditions either of that specified version or
of any later version that has been published (not as a draft) by the
Free Software Foundation.  If the Document does not specify a version
number of this License, you may choose any version ever published (not
as a draft) by the Free Software Foundation.  If the Document
specifies that a proxy can decide which future versions of this
License can be used, that proxy's public statement of acceptance of a
version permanently authorizes you to choose that version for the
Document.

11. RELICENSING

"Massive Multiauthor Collaboration Site" (or "MMC Site") means any
World Wide Web server that publishes copyrightable works and also
provides prominent facilities for anybody to edit those works.  A
public wiki that anybody can edit is an example of such a server.  A
"Massive Multiauthor Collaboration" (or "MMC") contained in the site
means any set of copyrightable works thus published on the MMC site.

"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0
license published by Creative Commons Corporation, a not-for-profit
corporation with a principal place of business in San Francisco,
California, as well as future copyleft versions of that license
published by that same organization.

"Incorporate" means to publish or republish a Document, in whole or in
part, as part of another Document.

An MMC is "eligible for relicensing" if it is licensed under this
License, and if all works that were first published under this License
somewhere other than this MMC, and subsequently incorporated in whole or
in part into the MMC, (1) had no cover texts or invariant sections, and
(2) were thus incorporated prior to November 1, 2008.

The operator of an MMC Site may republish an MMC contained in the site
under CC-BY-SA on the same site at any time before August 1, 2009,
provided the MMC is eligible for relicensing.


ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and
license notices just after the title page:

    Copyright (c)  YEAR  YOUR NAME.
    Permission is granted to copy, distribute and/or modify this document
    under the terms of the GNU Free Documentation License, Version 1.3
    or any later version published by the Free Software Foundation;
    with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
    A copy of the license is included in the section entitled "GNU
    Free Documentation License".

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
replace the "with...Texts." line with this:

    with the Invariant Sections being LIST THEIR TITLES, with the
    Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License,
to permit their use in free software.