Translations/en_US/FlightGear-nonQt.xlf is for a proper English
translation, where for instance "found %n airport(s)" would have two
plural forms, "found %n airport" and "found %n airports" (most
non-plural strings can be taken verbatim from the default translation,
and at this point there is no plural form at all yet).
As they are registered here, the files will have virtual paths such as:
/Translations/de/FlightGear-nonQt.xlf
/Translations/en_US/FlightGear-nonQt.xlf
etc.
for the EmbeddedResourceManager ('/' being the default virtual prefix).
${CMAKE_SOURCE_DIR}/src/EmbeddedResources/FlightGear-resources.xml
(currently empty) is automatically "compiled" into
${CMAKE_BINARY_DIR}/src/EmbeddedResources/FlightGear-resources.[ch]xx by
fgrcc inside the build directory. These files are incorporated into the
FlightGear build (FlightGear-resources.cxx is linked into FlightGear).
When the XML embedded resource declaration file added here,
FlightGear-resources.xml, is compiled, fgrcc is passed the
--root=${CMAKE_SOURCE_DIR} option, so that files referred to in
FlightGear-resources.xml are looked up relatively to the root directory
of the FlightGear repository. One could use a second XML embedded
resource declaration file compiled with a different --root option to
grab files from FGData, for instance. I would name such a file
FGData-resources.xml to be consistent with the current naming scheme.
Note: this --root option applies to the paths of real files. Don't
confuse it with the 'prefix' attribute of <qresource> elements
inside XML resource declaration files (such as
FlightGear-resources.xml), which applies to the virtual path of
each resource defined beneath.
The commands in src/Main/CMakeLists.txt ensure that
FlightGear-resources.xml is recompiled with fgrcc whenever it is
changed, and obviously also when FlightGear-resources.cxx or
FlightGear-resources.hxx is missing. However, CMake doesn't know how to
parse fgrcc XML resource declaration files, therefore when a resource is
modified but the XML file it is declared in is not (here,
FlightGear-resources.xml), you have to trigger yourself a recompilation
of the XML resource declaration file to see the new resource contents
inside FlightGear. The easiest ways to do so are:
- either update the timestamp of the XML resource declaration file;
- or remove one or both of the generated files
(FlightGear-resources.cxx and FlightGear-resources.hxx here).
The EmbeddedResourceManager is created in fgMainInit() just after
Options::processOptions() set the language that was either requested by
the user or obtained from the system (locales). Resources from
FlightGear-resources.cxx are added to it, after which
EmbeddedResourceManager::selectLocale() is called with the user's
preferred locale (obtained with FGLocale::getPreferredLanguage()).
Upon reset (fgStartNewReset()), EmbeddedResourceManager::selectLocale()
is called in a similar way after Options::processOptions(), however in
this case the EmbeddedResourceManager instance doesn't have to be
recreated.
