diff --git a/lib/modules/Calendar.pmod/Event.pmod b/lib/modules/Calendar.pmod/Event.pmod
index 19423fe2bb40f24e61b7a526eee5b170126600d2..feaa295f517ced90a8cf4085a5a22065d10e5946 100644
--- a/lib/modules/Calendar.pmod/Event.pmod
+++ b/lib/modules/Calendar.pmod/Event.pmod
@@ -146,10 +146,8 @@ class Day_Event
//! @decl int scan_jd(Calendar.Calendar realm, int jd,@
//! int(-1..-1)|int(1..1) direction)
- //! These methods has to be defined, and is what
- //! really does some work. It should return the next or previos
- //! julian day (>@i{jd@}) when the event occurs,
- //! or the constant @[NODAY] if it doesn't.
+ //! This method has to be defined, and is what
+ //! really does some work.
//!
//! @param direction
//! @int
@@ -158,6 +156,11 @@ class Day_Event
//! @value -1
//! Backward (previous).
//! @endint
+ //!
+ //! @returns
+ //! It should return the next or previous
+ //! julian day (>@i{jd@}) when the event occurs,
+ //! or the constant @[NODAY] if it doesn't.
int scan_jd(Calendar.Calendar realm,int jd,int(1..1)|int(-1..-1) direction);
@@ -855,6 +858,157 @@ class Weekday
}
}
+//! This class represents a solar event.
+//!
+//! The @[event_type] is one of
+//! @int
+//! @value 0
+//! Northern hemisphere spring equinox.
+//! @value 1
+//! Northern hemisphere summer solstice.
+//! @value 2
+//! Northern hemisphere spring equinox.
+//! @value 3
+//! Northern hemisphere summer solstice.
+//! @endint
+class Solar(int|void event_type)
+{
+ inherit Day_Event;
+
+ protected float solar_event(int y)
+ {
+ float res;
+
+ if (y < 1000) {
+ float yy = y/1000.0;
+ float y2 = yy*yy;
+ float y3 = y2*yy;
+ float y4 = y3*yy;
+
+ switch (event_type) {
+ case 0:
+ res = 1721139.29189 + 365242.13740 * yy + 0.06134 * y2 -
+ 0.00111 * y3 - 0.00071 * y4;
+ break;
+ case 1:
+ res = 1721233.25401 + 365241.72562 * yy + 0.05323 * y2 -
+ 0.00907 * y3 - 0.00025 * y4;
+ break;
+ case 2:
+ res = 1721325.70455 + 365242.49558 * yy + 0.11677 * y2 -
+ 0.00297 * y3 - 0.00074 * y4;
+ break;
+ case 3:
+ res = 1721414.39987 + 365242.88257 * yy + 0.00769 * y2 -
+ 0.00933 * y3 - 0.00006 * y4;
+ break;
+ }
+ } else {
+ float yy = (y - 2000)/1000.0;
+ float y2 = yy*yy;
+ float y3 = y2*yy;
+ float y4 = y3*yy;
+
+ switch (event_type) {
+ case 0:
+ res = 2451623.80984 + 365242.37404 * yy + 0.05169 * y2 -
+ 0.00411 * y3 - 0.00057 * y4;
+ break;
+ case 1:
+ res = 2451716.56767 + 365241.62603 * yy + 0.00325 * y2 -
+ 0.00888 * y3 - 0.00030 * y4;
+ break;
+ case 2:
+ res = 2451810.21715 + 365242.01767 * yy + 0.11575 * y2 -
+ 0.00337 * y3 - 0.00078 * y4;
+ break;
+ case 3:
+ res = 2451900.05952 + 365242.74049 * yy + 0.06223 * y2 -
+ 0.00823 * y3 - 0.00032 * y4;
+ break;
+ }
+ }
+
+ float delta_y = (res - 2451545.0) / 36525;
+
+ float omega = 628.30759 * delta_y - 0.04311;
+ float l = 1.0 + 0.0334 * cos(omega) + cos(2.0 * omega);
+
+ float S =
+ 0.00485 * cos(5.6716 + 2.3411 * delta_y) +
+ 0.00203 * cos(5.8858 + 3.5686 * delta_y) +
+ 0.00199 * cos(5.9704 + 0.3523 * delta_y) +
+ 0.00182 * cos(0.4860 + 5.3601 * delta_y) +
+ 0.00156 * cos(1.2765 + 0.6438 * delta_y) +
+ 0.00136 * cos(2.9936 + 3.4635 * delta_y) +
+ 0.00077 * cos(3.8841 + 0.8540 * delta_y) +
+ 0.00074 * cos(5.1787 + 2.7036 * delta_y) +
+ 0.00070 * cos(4.2513 + 0.6547 * delta_y) +
+ 0.00058 * cos(2.0911 + 4.1564 * delta_y) +
+ 0.00052 * cos(5.1866 + 2.6298 * delta_y) +
+ 0.00050 * cos(0.3669 + 2.1158 * delta_y) +
+ 0.00045 * cos(4.3204 + 0.8650 * delta_y) +
+ 0.00044 * cos(5.6749 + 4.1182 * delta_y) +
+ 0.00029 * cos(1.0634 + 2.1540 * delta_y) +
+ 0.00028 * cos(2.7074 + 4.1072 * delta_y) +
+ 0.00017 * cos(5.0403 + 4.2316 * delta_y) +
+ 0.00016 * cos(3.4565 + 4.4336 * delta_y) +
+ 0.00014 * cos(3.4865 + 2.0407 * delta_y) +
+ 0.00012 * cos(1.6649 + 3.1040 * delta_y) +
+ 0.00012 * cos(5.0110 + 4.3940 * delta_y) +
+ 0.00012 * cos(5.5992 + 3.7919 * delta_y) +
+ 0.00009 * cos(3.9746 + 2.4804 * delta_y) +
+ 0.00008 * cos(0.2697 + 5.2198 * delta_y);
+
+ res += S / l;
+ return res;
+ }
+
+ //! @note
+ //! Returns unixtime in UTC to avoid losing the decimals!
+ int scan_jd(Calendar.Calendar realm, int jd, int(1..1)|int(-1..-1) direction)
+ {
+ [int y, int yjd, int leap] = gregorian_yjd(jd);
+
+ float res = solar_event(y);
+
+ if ((direction > 0) && (res < jd)) {
+ res = solar_event(y + 1);
+ } else if ((direction < 0) && (res >= jd)) {
+ res = solar_event(y - 1);
+ }
+
+ // Convert into an UTC timestamp.
+ return (int)((res - 2440588.0)*86400);
+ }
+
+ Calendar.TimeRanges.TimeRange next(void|Calendar.TimeRanges.TimeRange from,
+ void|int(0..1) including)
+ {
+ if (!from) from=std_day();
+ int jd;
+ if (including) jd=(int)(from->julian_day());
+ else jd=(int)(from->end()->julian_day());
+ int utc = scan_jd(from->calendar(),jd-nd+1,1);
+ return (from->calendar()->Day)("unix_r",utc,from->ruleset())*nd;
+ }
+
+ //! Uses the virtual method @[scan_jd].
+ //! @seealso
+ //! @[Event.previous]
+ Calendar.TimeRanges.TimeRange previous(void|Calendar.TimeRanges.TimeRange from,
+ void|int(0..1) including)
+ {
+ if (!from) from=std_day();
+ int jd;
+ if (including) jd=(int)(from->end()->julian_day());
+ else jd=(floatp(from->julian_day())
+ ?(int)floor(from->julian_day())
+ :(from->julian_day()-1));
+ int utc = scan_jd(from->calendar(),jd+nd-1,-1);
+ return (from->calendar()->Day)("unix_r",utc,from->ruleset())*nd;
+ }
+}
//! This class represents an easter.
class Easter
diff --git a/lib/modules/Calendar.pmod/Events.pmod b/lib/modules/Calendar.pmod/Events.pmod
index 05b9d9f56c7309e3b38359efcd82b99c495fb755..94578156057e90073c2e93eaf6b92ce56862a018 100644
--- a/lib/modules/Calendar.pmod/Events.pmod
+++ b/lib/modules/Calendar.pmod/Events.pmod
@@ -141,7 +141,18 @@ Event.Event make_event(string source)
n,days)>=2)
return Event.Easter_Relative(id,s,n);
error("Events: rule error; unknown rule format:\n%O\n",source);
-
+
+ case "Equinox":
+ if (sscanf(rule, "Equinox%*[ \t]%s", string type)) {
+ switch(String.trim_all_whites(type)) {
+ case "Vernal":
+ return Event.Solar(0);
+ case "Autumnal":
+ return Event.Solar(2);
+ }
+ }
+ error("Events: rule error; unknown rule format:\n%O\n",source);
+
case "Weekday":
if (sscanf(rule,"Weekday%*[ \t]%s%*[ \t]%d days",
wd,days)>=2 && (n=wd2n[wd]))