README

Table of Contents
=================

 1. Introduction
 2. Dependencies
 3. Building
 4. Bugs
 5. Translations
 6. Covers
 7. CUE Files
 8. Streams
 9. MultiMedia Keys
10. DBUS Actions
11. Dynamic Helper Script - Local Mode
12. Dynamic Helper Script - Server Mode
13. Source Code
14. Debug Logging
15. Credits
16. Windows
17. macOS



1. Introduction
===============

Cantata is a graphical client for MPD. It contains the following features:

 1. Support for Linux, macOS, and Windows.
 2. Multiple MPD collections.
 3. Highly customisable layout.
 4. Songs grouped by album in play queue.
 5. Context view to show artist, album, and song information of current track.
 6. Simple tag editor.
 7. File organizer - use tags to organize files and folders.
 8. Ability to calculate ReplyGain tags. (if enabled at build-time)
 9. Dynamic playlists.
10. Online services; Jamendo, Magnatune, and Podcasts.
11. Radio stream support - with the ability to search for streams via TuneIn,
    ShoutCast, or IceCast.
12. USB-Mass-Storage and MTP device support. (if enabled at build-time)
13. Audio CD ripping and playback. (if enabled at build-time)
14. Playback of non-MPD songs - via simple in-built HTTP server if connected
    to MPD via a standard socket, otherwise filepath is sent to MPD.
15. MPRISv2 DBUS interface.
16. Basic support for touch-style interface (views are made 'flickable')
17. Scrobbling.
18. Ratings support.

This version of Cantata continues on CDrummond's work, which was
originally a fork of QtMPC. The code (and user interface)
is now *very* different to that of QtMPC.

Unlike most other MPD clients, Cantata caches a copy of the MPD music library.
This is so that it can create a proper hierarchy of artists and albums (where
Cantata will use the AlbumArtist tag if found, otherwise it will fallback to
the Artist tag), to provide album counts, tracks counts, etc in the browser
views and tooltips, and also to help with copying songs to/from devices.

This cache is updated only when MPD indicates that its version of the collection
is different to Cantata's.


2. Dependencies
===============

Cantata requires the following Qt libraries:

1. QtCore
2. QtGui
3. QtNetwork
4. QtXml
5. QtSql
6. QtDBus (Only for Linux builds)
7. QtWidgets 
8. QtMultimedia / libVLC - depends on ENABLE_HTTP_STREAM_PLAYBACK and
   ENABLE_LIBVLC
9. QtSvg

Cantata may also use the following optional libraries:

1. TagLib - Tag edit dialog, replaygain, track organizer, and UMS device
            support.
2. LibMTP - MTP devices.
3. FFMPEG (libavcodec) - ReplayGain detection code.
4. MPG123 - ReplayGain detection code.
5. CDParanoia - Read/rip Audio CDs.
6. CDDB - either this or MusicBrainz5 required for Audio CDs
7. MusicBrainz5 - either this or CDDB required for Audio CDs
8. LibEbur128 - ReplayGain detection code. If this is not found on the
   system then Cantata will use its own bundled copy.
9. libavahi-common / libavahi-client - Avahi support (automatic mpd discovery)


3. Building
===========

Please refer to the INSTALL file for general build instructions. Details on how
Cantata is build for Windows can be found in section 16, and macOS in section
17.


4. Bugs
=======

Before reporting bugs, please check that this is not an MPD related issue with
your system - e.g. please try recreating the issue with another MPD client,
such as MPDroid, GMPC, etc.

To report bugs please visit https://github.com/nullobsi/cantata

When reporting a bug, please mention the Cantata version number, the Cantata
build type (Linux, Windows, Mac), any cmake options you specified
(other than the defaults listed at the top of the INSTALL file), and the
version of MPD you are using.


5. Translations
===============

As of version 2.1.0, Cantata uses Qt's translation framework.

To generate a new translation for Cantata:

1. Copy translations/blank.ts to cantata_LANG_CODE.ts
   (Replace LANG_CODE with the language code for the desired language, e.g. 
   'fr' for French - so this would be cantata_fr.ts)
2. Open your new ts file with Qt Linguist.
3. In Qt Linguist set the target language and country.
4. Update the translations.
5. Either email me the new translation (address is in the AUTHORS file), or
   create a pull request on github.


6. Covers
=========

When displaying covers, Cantata will load album covers in the following order:

${configuredName} is either:
a. cover - if not configured in Cantata's config dialog
b. Setting from cantata with the following replacements:
    %albumartist% => Album Artist
    %artist% => Track Artist
    %album% => Album Name
    Any other % removed

...if configured to 'Cache scaled covers', Cantata will check its scaled-covers
   cache folder (~/.cache/cantata/covers-scaled/SIZE) for:

 1. ${albumArtist}/${album}.png

...if MPD folder exists, is not specified as a http URL, and is readable, then
   cantata will look for the following within the folder containing the song:

 2. ${configuredName}.jpg - if set
 3. ${configuredName}.png - if set
 4. cover.jpg
 5. cover.png
 6. AlbumArt.jpg
 7. AlbumArt.png
 8. folder.jpg
 9. folder.png
10. ${albumArtist} - ${album}.jpg
11. ${albumArtist} - ${album}.png
12. ${album}.jpg
13. ${album}.png
14. Image embedded within current song's tags.
15. ANY other jpg, or png

...then Cantata will check its cache folder (~/.cache/cantata/covers), for :

16. ${albumArtist}/${album}.jpg
17. ${albumArtist}/${album}.png

...if the MPD folder was specified as a http URL

18. ${url}/${dirFromFile}/cover.jpg
    - or ${url}/${dirFromFile}/${configuredName}.jpg (if set)
19. ${url}/${dirFromFile}/cover.png
    - or ${url}/${dirFromFile}/${configuredName}.png (if set)

...lastly, if user has enabled downloading via last.fm

20. Query last.fm using ${albumArtist} and ${album}. Cantata will attempt to
    download the image specified with the "extralarge" size.

Downloaded images will be saved as ${configuredName}.jpg/png (if set), or
cover.jpg/png, within the song folder if possible. If not, then they will be
saved in Cantata's cache folder.

If configured to 'Cache scaled covers', then the resized cover (as displayed)
will be saved as a PNG within covers-scaled.


For artist images:

${configuredName} is either:
a. artist - if configured Album cover ${configuredName} is empty, or does not
   contain %
b. ${albumArtist} - if configured Album cover ${configuredName} contains % and
   ${albumArtist} is not 'Various Artists'
c. ${basicArtist} if configured Album cover ${configuredName} contains % and
   ${albumArtist} is 'Various Artists'

...if configured to 'Cache scaled covers', Cantata will check its scaled-covers
   cache folder (~/.cache/cantata/covers-scaled/SIZE) for:

 1. ${albumArtist}.png

...if MPD folder exists, is not specified as a http URL, and is readable, then
   cantata will look for the following within the folder containing the song:

 2. ${basicArtist}.jpg
 3. ${basicArtist}.png
 4. ${configuredName}.jpg
 5. ${configuredName}.png

...the above will be repeated for the parent folder

...if song is from a Various Artists album, or file is a non-MPD file, then
   cantata will look for the following within the MPD root folder:

 6. ${basicArtist}/${basicArtist}.jpg
 7. ${basicArtist}/${basicArtist}.png
 8. ${basicArtist}/${configuredName}.jpg
 9. ${basicArtist}/${configuredName}.png

...then Cantata will check its cache folder (~/.cache/cantata/covers), for :

10. ${albumArtist}.jpg
11. ${albumArtist}.png

...if the MPD folder was specified as a http URL

12. ${url}/${dirFromFile}/${configuredName}.jpg
13. ${url}/${dirFromFile}/${configuredName}.png
 
...the above will be repeated for the parent folder

...lastly, if user has enabled downloading via last.fm

14. Query last.fm using ${albumArtist}. Cantata will attempt to download the
    image specified with the "extralarge" size.

Downloaded images will be saved as artist.jpg/png, within the artist folder
if the folder hierarchy is 2 levels (artist/album/) and the user has write
permissions. If not, then they will be saved in Cantata's cache folder.

If configured to 'Cache scaled covers', then the resized cover (as displayed) 
will be saved as a PNG within covers-scaled.


For composer images:

...if configured to 'Cache scaled covers', Cantata will check its scaled-covers
   cache folder (~/.cache/cantata/covers-scaled/SIZE) for:

1. ${composer}.png

...if MPD folder exists, is not specified as a http URL, and is readable, then
   cantata will look for the following within the folder containing the song:

2. composer.jpg
3. composer.png

...the above will be repeated for the parent folder

...then Cantata will check its cache folder (~/.cache/cantata/covers), for :

4. ${composer}.jpg
5. ${composer}.png

...if the MPD folder was specified as a http URL

6. ${url}/${dirFromFile}/composer.jpg
7. ${url}/${dirFromFile}/composer.png

...the above will be repeated for the parent folder

Downloaded images will be saved as composer.jpg/png, within the artist folder
if the folder hierarchy is 2 levels (artist/album/) and the user has write
permissions. If not, then they will be saved in Cantata's cache folder.

If configured to 'Cache scaled covers', then the resized cover (as displayed)
will be saved as a PNG within covers-scaled.


For context view backdrops:

...if MPD folder exists, is not specified as a http URL, and is readable, OR
   the song's filename starts with '/', then cantata will look for the
   following within the folder containing the song:

 1. ${currentArtist}-backdrop.jpg
 2. ${currentArtist}-backdrop.png
 3. backdrop.jpg
 4. backdrop.png

...the above will be repeated for the parent folder

...if song is from a Various Artists album, or file is a non-MPD file, then
   cantata will look for the following within the MPD root folder:

 5. ${currentArtist}/${currentArtist}-backdrop.jpg
 6. ${currentArtist}/${currentArtist}-backdrop.png
 7. ${currentArtist}/backdrop.jpg
 8. ${currentArtist}/backdrop.png

...then Cantata will check its cache folder (~/.cache/cantata/backdrops), for :

 9. ${currentArtist}.jpg

...internet services:

10. MusizBrainz is queried for an artist ID. If returned, this artist ID is used
    to locate a cover from fanart.tv
11. Download image from discogs

...lastly:

12. If all the above fails, a backdrop is created from all the album covers
    featuring the artist.

Downloaded images will be saved as backdrop.jpg, within the artist folder
if the current song is not from a Various Artists album, the file is from MPD,
the folder hierarchy is 2 levels (artist/album/), and the user has write
permissions. If not, then they will be saved in Cantata's cache folder.


7. CUE Files
============

If Cantata is running with MPD>=0.17, then it will attempt to parse the contents
of CUE files. The CUE file will be parsed to ascertain the album and track
details. The track durations for all bar the last should be accurate, and
Cantata will attempt to determine the duration of the last track - but this
might not be 100% accurate.

If the CUE file references an audio file that does not exist in the MPD music
folder, then the CUE file contents will NOT be used.

There is no reliable way for Cantata to ascertain the text encoding that a CUE
file uses - so, for portability, it would be best if your CUE files used UTF-8
encoding. When loading a CUE file, Cantata will attempt to load the file as if
it was UTF-8 encoded, if this fails it will try with the "System" codec. You may
add to this list of encodings to try by using the 'cueFileCodecs' config item
(as detailed in section 7 above). If Cantata fails with all configured
encodings, then it will 'peek' at the 1st 1k bytes, and ask Qt to see if it can
determine the encoding - and fallback to UTF-8 otherwise. (This peeking and
fallback was how Cantata behaved in pre 1.2 versions - and is how Clementine
behaves (where Cantata's CUE file support originates from.))

NOTE: If Cantata cannot access the CUE file (as MPD is running on a remote host,
or you have not configured the music folder correctly, etc.) then Cantata will
add the CUE File to the album's track listing.


8. Streams
==========

As of 1.4.0, Cantata only comes with TuneIn, ShoutCast, and IceCast
stream providers. To install new providers, you can either use Cantata's
download dialog (to install for Cantata's extras github repo), or install from
file. To import new stream categories into Cantata, these files need to be GZip
compressed tarballs of the following format.

  Filename: CATEGORY_NAME.streams  (e.g. German Radio.streams)

  Contents: Either streams.xml, streams.xml.gz, OR settings.json, AND
            Either icon.png OR icon.svg

            streams.xml.gz should be GZip compressed.
            icon.svg should be a non-compressed SVG file.

            Icons for sub-categories (first level only) - these should be named
            the same as the category (with / replaced by _) -
            e.g. 'Hard_Soft Rock.svg' for 'Hard/Soft Rock')

settings.json is really only intended to be used by Cantata for providers
stored in its extras github repo. This JSON file has the following syntax:

  { "type": "streamType", "url": "Stream listing URL" }
  
  "streamType" can be either di, soma, or listenlive. Cantata contains code to
  download from "Stream listing URL" and parse the response based upon
  "streamType"

In general, for externally provided stream lists, it is more convenient to just
list all a providers streams within stream.xml.gz. This has the following
format:

  <?xml version="1.0" encoding="UTF-8"?>
  <streams version="1.0" addCategoryName="true">
    <stream name="Station Name" url="http://station.stream.url"/>
  </streams>

if "addCategoryName" is set to true, then when Cantata adds a station from this
category to either favourites or the playqueue, it will prepend the Category
name to the station name.

e.g. To create a stream category named "Wicked Radio" that has 2
sub-categeries, and 3 stream URLs you would need:

streams.xml.gz with:
  <?xml version="1.0" encoding="UTF-8"?>
  <streams version="1.0" addCategoryName="true">
    <category name="Rock">
      <stream name="Hard Rock" url="http://127.0.0.1/hard.ogg"/>
      <stream name="Soft Rock" url="http://127.0.0.1/soft.ogg"/>
    </category>
    <stream name="Blues" url="http://127.0.0.1/blues.ogg"/>
  </streams>

streams.xml.gz & icon.svg need to be placed into a GZip compressed tarball
named "Wicked Radio.streams"

With the above example, Cantata would list the following in the streams view:

> Wicked Radio
   > Rock
       Hard Rock
       Soft Rock
   Blues

When "Hard Rock" is added to the playqueue, it will be listed as
"Wicked Radio - Hard Rock"

If Rock.png (or Rock.svg) and/or Blues.png (or Blues.svg) also exist in the
tarball, then they will be copied to the install location and used as icons for
the respective category.

To create .streams file:
    1. Place all files in a temp folder
    2. cd into temp folder
    3. tar cfz NAME.tar.gz *
    4. mv NAME.tar.gz NAME.streams


cantata-extra on github
-----------------------

**CDrummond no longer maintains Cantata.** In the future, these links
will be updated. Please do not contact CDrummond for assitance, instead
open a GitHub issue on the new repository.

The streams page on Cantata's settings dialog, will allow you to install new
providers from Cantata's extras github repo. To do this, the dialog first
downloads the list of providers, this is obtained from the following URL:

https://raw.githubusercontent.com/CDrummond/cantata-extra/master/streams/2.1/list.xml

The contents of this file will be something like:

<providers>
 <category type="0">
  <provider name="1.fm" md5="cbd6ad834d4493662952a653cea5c779"/>
  ...

If you want to manually download a provider, use the listed URL to download the
.streams file. e.g. for the above:

    wget https://raw.githubusercontent.com/CDrummond/cantata-extra/master/streams/2.1/1.fm.streams.gz

Extract the contents with:

    tar zxvf 1.fm.streams.gz

If you wish to distribute a new stream provider via Cantata's extras github
repo, please send me an email with the .streams.gz file. My address is in the AUTHORS
file.


9. MultiMedia Keys
==================

Linux and Windows builds, as of 1.2, now also support basic media-keys
shortcuts.

Linux use the GNOME settings daemon's MediaKeys interface. This interface is
normally started automatically under GNOME/Unity.


10. DBUS Actions
================

All of Cantata's internal actions are accessible via DBUS. The
cantata-remote helper script may be used to invoke these, e.g. to toggle
playback:

    cantata-remote cantata playpausetrack

The list of action names maybe obtained by calling the listActions DBUS method,
e.g.:

    qdbus dog.unix.cantata.Cantata /cantata listActions


11. Dynamic Helper Script - Local Mode
======================================

When a dynamic playlist is loaded in Cantata, the cantata-dynamic helper script
is executed in the background to do the actual song selection. In this way the
dynamic playlist can still function even when cantata is terminated. It is
possible for this script to be controlled on the command line (although it was
never written with this in mind).

The list of dynamic playlists may be obtained by looking in
~/.local/share/cantata/dynamic

To 'load' a dynamic playlist, all you need to do is symlink the desired one in
~/.local/share/cantata/dynamic to ~/.cache/cantata/dynamic/rules. Then you can
start the helper by calling '/usr/share/cantata/scripts/cantata-dynamic start'
(or first call '/usr/share/cantata/scripts/cantata-dynamic stop' to stop any
current playlist).

To pass connection details, cantata-dynamic reads the same environment variables
as mpc - namely MPD_HOST and MPD_PORT

e.g. the following bash script (not tested!) will stop any current dynamic
playlist, load the 'MyPlaylist' playlist, and start this on the mpd at
'hostname:1234' with password 'pass'

    # Stop current dynamic playlist
    /usr/share/cantata/scripts/cantata-dynamic stop
    # Clear the playqueue (this requires mpc)
    MPD_HOST=pass@hostname MPD_PORT=1234 mpc clear
    # 'Load' new playlist
    if [ -f "$HOME/.cache/cantata/dynamic/rules" ] ; then
        rm "$HOME/.cache/cantata/dynamic/rules"
    fi
    ln -s "$HOME/.local/share/cantata/dynamic/MyPlaylist.rules" "$HOME/.cache/cantata/dynamic/rules"
    # Restart dynamic script
    MPD_HOST=pass@hostname MPD_PORT=1234 /usr/share/cantata/scripts/cantata-dynamic start


12. Dynamic Helper Script - Server Mode
=======================================

In addition to the above, the helper script may be installed on the system
containing MPD, and run in 'server' mode. This requires MPD>=0.17, as
communications are via MPD's client-to-client messages.

When run in this mode, it is intended that the script be run system-wide and
started when the system (or MPD) is started. e.g. The script should be started
as:

    <prefix>/share/cantata/scripts/cantata-dynamic server <location of config file>

    e.g.:  /usr/share/cantata/scripts/cantata-dynamic server /etc/cantata-dynamic.conf

When run as described above, the script will automatically daemonize itself.

To stop the dynamizer:

     <prefix>/share/cantata/scripts/cantata-dynamic stopserver

    e.g.:  /usr/share/cantata/scripts/cantata-dynamic stopserver

When MPD informs Cantata that the 'cantata-dynamic-in' channel has been
created, Cantata will automatically switch itself to server mode. The list of
rules is then loaded from the server, and Cantata will change the backdrop of
the dynamic page to indicate that the rules are comming from the server.

Server mode is currently the only way for dynamic playlists to be used under
Windows.


Configuration
-------------

The server mode has a simple ini-style configuration file, that has the
following parameters (shown here with the default values):

    pidFile=/var/run/cantata-dynamic/pid
    filesDir=/var/lib/mpd/dynamic
    activeFile=/var/run/cantata-dynamic/rules
    mpdHost=localhost
    mpdPort=6600
    mpdPassword=
    httpPort=0

'pidFile' When started, the script will store its PID within the file
configured here. This is then used to detect if the script is running, etc.

'filesDir' This controls where the dynamic rules are stored. The user the script
is run as should have read/write permissions to this folder.

'activeFile' When a set of rules is made 'active', all cantata does is create a
symbolic link from the rules file to the file specified in 'activeFile'. Again,
the user the script is run as should have read/write permissions to this file.

'mpdHost', 'mpdPort', and 'mpdPassword' are the connection details of the MPD
server.

'httpPort' if this is set to non-zero, then the script will serve up a *very*
simple HTTP control page - allowing playlists to be started and stopped.


Installation
-------------

Within the playlists folder is a systemd service file.

NOTE: This service file assumes cantata has been installed to /usr, and that
cantata-dynamic is in /usr/share/cantata/scripts. If this is not the case, then
this will need to be edited.

Copy playlists/cantata-dynamic.conf to /etc, and edit as appropriate.


13. Source Code
===============
The Cantata source folder contains the following structure:

    3rdparty   - Third party libraries
    cmake      - CMake scripts
    context    - Context view classes
    dbus       - DBUS related classes and XML files
    devices    - Device related classes
    playlists  - Playlists
    gui        - General GUI classes, e.g. MainWindow, LibraryPage, etc.
    http       - HTTP server
    icons      - Icons
    models     - Most models, apart from dynamic playlist and shortcut models
    mpd        - MPD related classes; connection, status, song, etc.
    network    - Generic Network classes (and proxy support for Qt builds)
    online     - Jamendo, Magantune, SoundCloud, and Podcasts
    po         - Translations
    replaygain - ReplayGain calculation
    streams    - Internet radio streams
    support    - Generic classes that /may/ be useful to other projects.
                 Mainly used for Qt and Gtk support.
    tags       - Tag reading, editing, etc.
    widgets    - Widgets that are probably Cantata specific.
    windows    - Files specfic to Windows builds..
    mac        - Files specfic to MacOSX builds.

Cantata's SVG icons have been 'cleaned' using:
  scour --strip-xml-prolog --indent=none -i in.svg -o out.svg

Symbolc media icons are taken from gnome icon theme, but have been scaled with
  rsvg-convert -a -w 128 -f svg in.svg -o out.svg


14. Debug Logging
=================

Cantata contains some debug logging that might help to diagnose certain issues.
To enable this, you need to use the --debug commandline option. This option
takes a comma-separated list of debug areas.
Therefore, its probably better to start Cantata from the commandline.

The following debug areas may be used:

    MPD communications        mpd
    MPD Parsing               mpdparse
    Covers                    covers (or covers-verbose)
    Wikipedia context info    context-wikipedia
    Last.fm context info      context-lastfm
    Combined context info     context-info
    Context widget            context-widget
    Context lyrics            context-lyrics
    Dynamic                   dynamic
    Stream fetching           stream-fetcher
    Http server               http-server
    Song dialog file checks   song-dialog
    Network access            network-access
    Threads                   threads
    External tags             tags
    Scrobbling                scrobbler
    Devices                   devices
    SQL                       sql
    MPD HTTP stream playback  http-stream
    MPD auto discover         avahi
    Media keys                media-keys
    Cusrtom actions           custom-actions

To log debug to a file use --debug-to-file. e.g. To log MPD communications and
cover access to a file, start cantata as follows:

    cantata --debug=mpd,covers --debug-to-file


The loccation of the debug file will vary dependant upon OS. On Linux systems
this will be ~/.cache/cantata/cantata.log For Windows this will be
C:\Users\USERNAME\AppData\Local\mpd\cantata\cache\cantata.log And for OSX it
will be /Users/$USER/Library/Caches/cantata/cantata/cantata.log


NOTE: Debug logging will function regardless of whether you have created a
Debug or Release build.


15. Credits
===========

Cantata contains code/icons from:

    Amarok             - amarok.kde.org (Transcoding, Cover fetching code in
                         cover dialog)
    Clementine         - www.clementine-player.org (Lyrics searches, CUE file
                         parsing, digitally imported support, and stretched
                         header view)
    Be::MPC            - Wikipedia parsing code
    Quassel            - quassel-irc.org (Qt-only keyboard short-cut config
                         support)
    Solid              - solid.kde.org (Device detection for Qt-only builds)
    Asunder            - CDDB code
    libkcddb           - MusicBrainz code
    libebur128         - https://github.com/jiixyj/libebur128 (Replay gain
                         calculation)
    IcoMoon            - http://icomoon.io/#icons (Monochrome sidebar icons)
    Qxt                - Multi-media key support
    QtSolutions        - QtIOCompressor, and QtSingleApplication
    QMPDClient         - Last.fm scrobbling


16. Windows
===========

The easiest way to develop Cantata for Windows is to use the MSYS2
environment. MSYS2 provides a ready-made development environment with
all of the libraries that Cantata needs as packages which can be
installed.

Consult the GitHub actions configuration for more information; the MSYS2
packages required are taglib, cmake, ninja, and the Qt libraries. Then,
Cantata can be compiled like any other CMake project:
	
	cmake -Bbuild -G Ninja -DCMAKE_BUILD_TYPE=Release
	cmake --build build -j 4
	...

The Cantata installer is made with WiXv3 and CPack. Install and add WiX
to your PATH, then you can simply run `cpack` in the build directory to
create a standalone .MSI installer for Cantata.

17. macOS
=========

Cantata builds on macOS using either Homebrew or the official Qt
packages. When building a Universal binary for ARM64 and x86_64, it's
reccomended to use the Qt distribution because their binaries come with
both architectures.

Unfortunately, the TagLib currently in the Homebrew repositories is an
older version. Installing a newer version of TagLib from source is
reccomended, as Cantata now required TagLib version 2.

Once the Qt libraries are installed, ensure you also have CMake and
Ninja installed. Then, you can build Cantata using CMake:

	cmake -Bbuild -G Ninja -DCMAKE_BUILD_TYPE=Release
		-DCMAKE_PREFIX_PATH=$HOME/Qt (if using Qt distribution)
	cmake --build build -j4

To create a DMG file for distribution, simply run `cpack` in the build
directory. The Qt libraries will be copied to make a standalone
executable.