add moonrise/moonset face

lib/moonrise/moonrise.h

@@ -0,0 +1,43 @@
+#ifndef MoonRise_h
+#define MoonRise_h
+
+#include <stdint.h>
+#include <stdbool.h>
+
+// Size of event search window in hours.
+// Events further away from the search time than MR_WINDOW/2 will not be
+// found.  At higher latitudes the moon rise/set intervals become larger, so if
+// you want to find the nearest events this will need to increase.  Larger
+// windows will increase interpolation error.  Useful values are probably from
+// 12 - 48 but will depend upon your application.
+
+#define MR_WINDOW 48 // Even integer
+
+typedef struct {
+  double RA;          // Right ascension
+  double declination; // Declination
+  double distance;    // Distance
+} skyCoordinates;
+
+typedef struct {
+  uint32_t queryTime;
+  uint32_t riseTime;
+  uint32_t setTime;
+  float riseAz;
+  float setAz;
+  bool hasRise;
+  bool hasSet;
+  bool isVisible;
+} MoonRise;
+
+MoonRise MoonRise_calculate(double latitude, double longitude, uint32_t t);
+
+//  private:
+void testMoonRiseSet(MoonRise *self, int i, double offsetDays, double latitude,
+                     double longitude, skyCoordinates *mp);
+skyCoordinates moon(double dayOffset);
+double interpolate(double f0, double f1, double f2, double p);
+double julianDate(uint32_t t);
+double localSiderealTime(double offsetDays, double longitude);
+
+#endif