Proposal for setting and display of time scales, date scales and time zones

[alex-w]

Original report by Volker H.: https://bugs.launchpad.net/stellarium/+bug/1214351

Following a short discussion with Alexander Wolf I propose to add settings and display of date scales, time scales and time zones. Here are my initial ideas:

• All date/time related settings of Stellarium could extend the existing Stellarium date/time dialog window and a button "Settings" could be added.

• Once "Settings" is selected the date/time dialog window gets extended by a number of tick-boxes, time displays etc. which allow

o the setting of the desired date and time value (in the current windows as well as in the extended window).
o the selection of different time scales (UTC, UT1, TAI, TT, TDT, older time scales, etc.).
o the selection of different deltaT algorithms.
o the selection of different date scales (julian, gregorian, proleptic gregorian, etc.).
o the various settings to become the "Stellarium default settings" via a button "set as Stellarium default".
o the various settings to become the "Stellarium start up settings" via a button "set as Stellarium start up". This could include the time settings from "Stellariums configuration dialogs".
o the display of the individual time values next to the applicable time scale tick-boxes.
o the display of the individual date values next to the applicable date scale tick-boxes.
o the display of the related JD, MJD, etc.
o the display of the deltaT value.
o the display of local apparent time, local mean time, equation of time, sidereal time etc.

• Pending on the entered date the possibility to set of certain time scales could get enabled or disabled. This has to be in accordance with the "official introduction" of certain time scales.

• The collapsed date/time dialog could display the selected date scale behind the date value and the selected time scale behind the time value.

• The current date/time display in Stellariums button menu bar could be extended accordingly and while hovering over it all date/time values could be displayed

• As an alternative to the input of date and time values the extended date/time dialog could also allow JD, MJD, Besselian year etc. as input values.

• Regardless of JD, MJD, Besselian year being the input values the small date/time dialog should always show the related date and the related time.

• If date and time values being the input values the JD, MJD, Besselian year fields should always show the related values.

• All other displayed time scales should be set accordingly

• Selection of a time zone different from the home time zone should be possible in the above context.

Not being an expert myself I hope that the Stellarium experts will understand what I am heading for.

With kind regards
Volker

[gzotti]

Some things should be left to the OP (as the only one who knows how he wants it) or his paid programmers. This could be implemented in a web interface, you need a full-screen GUI for all those numbers. Our time interface is JDE. All else is way too complicated for all but ~2000 users (my estimate) worldwide. When developing it, why not add 37 historic calendar systems as well?

[github-actions]

This is a good task for the community to participate in the contribution into Stellarium. Who wants to help us?