IQ.Pilot Release Commit @ 0798119

selfdrive/ui/lib/solar.py

@@ -0,0 +1,36 @@
+import math
+from datetime import UTC, datetime
+
+_J2000 = datetime(2000, 1, 1, 12, 0, 0, tzinfo=UTC)
+SUNSET_ELEVATION_DEG = -0.833  # standard sunset/sunrise threshold, corrected for atmospheric refraction
+
+
+def sun_elevation_deg(lat: float, lon: float, dt_utc: datetime | None = None) -> float:
+  """Low-precision solar elevation angle (accurate to well under a degree), per the
+  standard Meeus-derived approximation. lat/lon in degrees (lon positive east)."""
+  dt_utc = dt_utc or datetime.now(UTC)
+  n = (dt_utc - _J2000).total_seconds() / 86400.0
+
+  mean_lon = math.radians((280.460 + 0.9856474 * n) % 360)
+  mean_anomaly = math.radians((357.528 + 0.9856003 * n) % 360)
+  ecliptic_lon = (mean_lon + math.radians(1.915) * math.sin(mean_anomaly)
+                  + math.radians(0.020) * math.sin(2 * mean_anomaly))
+  obliquity = math.radians(23.439 - 0.0000004 * n)
+
+  declination = math.asin(math.sin(obliquity) * math.sin(ecliptic_lon))
+  right_ascension = math.atan2(math.cos(obliquity) * math.sin(ecliptic_lon), math.cos(ecliptic_lon))
+
+  equation_of_time_deg = math.degrees(mean_lon - right_ascension)
+  equation_of_time_deg = (equation_of_time_deg + 180) % 360 - 180
+
+  utc_hours = dt_utc.hour + dt_utc.minute / 60 + dt_utc.second / 3600
+  hour_angle = math.radians(15 * (utc_hours - 12) + lon + equation_of_time_deg)
+
+  lat_rad = math.radians(lat)
+  elevation = math.asin(math.sin(lat_rad) * math.sin(declination)
+                         + math.cos(lat_rad) * math.cos(declination) * math.cos(hour_angle))
+  return math.degrees(elevation)
+
+
+def is_after_sunset(lat: float, lon: float, dt_utc: datetime | None = None) -> bool:
+  return sun_elevation_deg(lat, lon, dt_utc) < SUNSET_ELEVATION_DEG