This is used by software centres such as GNOME Software to display
information about the app, both before and after it is installed.
The <id> used here follows the recommendations in the Appstream
specification, with the exception of violating the spec's strong
encouragement to use only lowercase characters. This is because the
version that is already published by Flathub uses an uppercase T in the
final component of the ID.[0] The file shipped by Fedora followed an older
convention of using the desktop file name as the ID. This is
acknowledged by the <provides> section near the bottom of the file,
which will allow software centres to associate the reverse-domain-name
ID with the older ID.[1]
Many fields in this file are translatable. This was the motivation for
the preceeding two changes:
- By using xgettext rather than intltool, the untranslated template may
be written using the normal appstream XML tags, rather than needing to
use (for example) <_name>Tux Paint</_name> to mark that field for
translation, which renders the template not valid for tools like
'appstreamcli validate'.
- Merging translations at build time, rather than committing the
translated XML to the repo as well, avoids another potentially
error-prone manual step when updating the source file or translations.
The release notes are taken from the press releases on the Tuxpaint
website. They will be extracted for translation. Another option is to
replace the <description> with <url type="details">...</url>, but AFAIK
no software centres currently show these URLs.[2]
[0]: https://www.freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-id-generic
[1]: https://www.freedesktop.org/software/appstream/docs/sect-Metadata-Application.html#tag-id-desktopapp
[2]: https://www.freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-releases
TODO:
- align comment
Fixes: https://sourceforge.net/p/tuxpaint/feature-requests/172/
Previously, both the .desktop.in template and the final .desktop file
were checked into source control.
While in some ways convenient, the manual step of updating it may be
forgotten after updating a translation or adjusting the template. It
also potentially introduces confusion as to which file to modify.
Instead, generate the .desktop file at build time. Since this is now
done using msgfmt rather than intltool, there is no additional
dependency beyond gettext, which is already used at build time to
compile .po files to .mo files.
Previously `make install` on macOS created TuxPaint.dmg, but it was a
simple disk image.
Now TuxPaint.dmg is formatted as one would expect from any other macOS app,
with a Tux folder icon, symlink to the /Applications folder, and a
background image with an arrow.
