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Secondary Calendar

View any loaded calendar side-by-side with the primary calendar. Shows the equivalent date on a different calendar system, with a month grid and navigation controls.


  • Click an equivalent date link in the BigCal/MiniCal header
  • API: CALENDARIA.api.showSecondaryCalendar(calendarId)

Shows a month grid for the selected secondary calendar, centered on the equivalent date of the primary calendar’s current view.

  • Weekday headers
  • Day cells showing the current equivalent date highlighted
  • Previous/next month days shown in faded style

A dropdown in the header lists all loaded calendars except the active primary calendar. Selecting a different calendar switches the viewer to that calendar’s month grid.

For calendars without months (like Traveller), the viewer displays a week-based grid:

  • 3-week sliding window (previous, current, next week)
  • Navigation moves by week instead of month
  • Header displays “Week X, Year” instead of month name

ActionResult
Arrow buttonsMove by month (or week for monthless calendars)
Today buttonReturn to the equivalent of the current date
Calendar dropdownSwitch to a different secondary calendar

Cross-calendar date translation works through shared world time. All loaded calendars share the same underlying game.time.worldTime value. The viewer converts the primary calendar’s current date to the equivalent position on the secondary calendar by resolving through this shared time reference.

  • Every calendar interprets the same world time according to its own structure (months, weeks, year length, epoch)
  • Advancing time on the primary calendar updates equivalent dates on all secondary calendars
  • No manual mapping is needed. Conversion is derived from world time.

When calendars are selected in the “Equivalent Date Calendars” setting (Settings Panel > Home tab), equivalent dates from those calendars appear in several locations:

Equivalent dates from all other loaded calendars appear below the primary date. Clicking one opens the Secondary Calendar Viewer for that calendar.

Equivalent date links appear in the header, same as BigCal. Hidden in compact mode.

Note sheets show when the note’s date falls on each loaded calendar.

Hovering over a day cell shows equivalent dates from other calendars in the tooltip.


See API Reference for full details.