Optional compilation

[alex-w]

Expected Behaviour

Optional compilation (for example without GUI) is working

Actual Behaviour

Compilation after configuration with option -DSTELLARIUM_GUI_MODE=None is not possible. I fear compilation without scripting can be broken too.

P.S. After resolving problems we can add checks some optional compilations in CI

[gzotti]

Certainly possible. I have not tried None in the past 8 years or so. While I don't see the actual necessity for None, it is a pre-requisite for starting any alternative GUIs of course. Likewise with scripting, the focus was on running with either QtScript (Qt5) or QML (Qt6), not disabling it completely.

[alex-w]

OK, at least for all documented modular features optional compilation is working - see linked branch.