diff options
Diffstat (limited to 'game')
| -rw-r--r-- | game/environment.cpp | 40 |
1 files changed, 20 insertions, 20 deletions
diff --git a/game/environment.cpp b/game/environment.cpp index 1ef6e22..9ae3b14 100644 --- a/game/environment.cpp +++ b/game/environment.cpp @@ -45,49 +45,49 @@ Environment::getSunPos(const Direction2D position, const time_t time) using std::floor; using std::sin; using std::tan; - static const auto JD2451545 = "2000-01-01T12:00:00"_time_t; + static const auto jD2451545 = "2000-01-01T12:00:00"_time_t; // Calculate difference in days between the current Julian Day // and JD 2451545.0, which is noon 1 January 2000 Universal Time // Calculate time of the day in UT decimal hours const auto dDecimalHours = static_cast<float>(time % 86400) / 3600.F; - const auto dElapsedJulianDays = static_cast<float>(time - JD2451545) / 86400.F; + const auto dElapsedJulianDays = static_cast<float>(time - jD2451545) / 86400.F; // Calculate ecliptic coordinates (ecliptic longitude and obliquity of the // ecliptic in radians but without limiting the angle to be less than 2*Pi // (i.e., the result may be greater than 2*Pi) - const auto dOmega = 2.1429F - 0.0010394594F * dElapsedJulianDays; - const auto dMeanLongitude = 4.8950630F + 0.017202791698F * dElapsedJulianDays; // Radians - const auto dMeanAnomaly = 6.2400600F + 0.0172019699F * dElapsedJulianDays; - const auto dEclipticLongitude = dMeanLongitude + 0.03341607F * sin(dMeanAnomaly) - + 0.00034894F * sin(2 * dMeanAnomaly) - 0.0001134F - 0.0000203F * sin(dOmega); - const auto dEclipticObliquity = 0.4090928F - 6.2140e-9F * dElapsedJulianDays + 0.0000396F * cos(dOmega); + const auto dOmega = 2.1429F - (0.0010394594F * dElapsedJulianDays); + const auto dMeanLongitude = 4.8950630F + (0.017202791698F * dElapsedJulianDays); // Radians + const auto dMeanAnomaly = 6.2400600F + (0.0172019699F * dElapsedJulianDays); + const auto dEclipticLongitude = dMeanLongitude + (0.03341607F * sin(dMeanAnomaly)) + + (0.00034894F * sin(2 * dMeanAnomaly)) - 0.0001134F - (0.0000203F * sin(dOmega)); + const auto dEclipticObliquity = 0.4090928F - (6.2140e-9F * dElapsedJulianDays) + (0.0000396F * cos(dOmega)); // Calculate celestial coordinates ( right ascension and declination ) in radians // but without limiting the angle to be less than 2*Pi (i.e., the result may be // greater than 2*Pi) - const auto dSin_EclipticLongitude = sin(dEclipticLongitude); - const auto dY = cos(dEclipticObliquity) * dSin_EclipticLongitude; - const auto dX = cos(dEclipticLongitude); - auto dRightAscension = atan2(dY, dX); + const auto dSinEclipticLongitude = sin(dEclipticLongitude); + const auto decY = cos(dEclipticObliquity) * dSinEclipticLongitude; + const auto decX = cos(dEclipticLongitude); + auto dRightAscension = atan2(decY, decX); if (dRightAscension < 0) { dRightAscension = dRightAscension + two_pi; } - const auto dDeclination = asin(sin(dEclipticObliquity) * dSin_EclipticLongitude); + const auto dDeclination = asin(sin(dEclipticObliquity) * dSinEclipticLongitude); // Calculate local coordinates ( azimuth and zenith angle ) in degrees - const auto dGreenwichMeanSiderealTime = 6.6974243242F + 0.0657098283F * dElapsedJulianDays + dDecimalHours; + const auto dGreenwichMeanSiderealTime = 6.6974243242F + (0.0657098283F * dElapsedJulianDays) + dDecimalHours; const auto dLocalMeanSiderealTime - = (dGreenwichMeanSiderealTime * 15.0F + (longitude / degreesToRads)) * degreesToRads; + = ((dGreenwichMeanSiderealTime * 15.0F) + (longitude / degreesToRads)) * degreesToRads; const auto dHourAngle = dLocalMeanSiderealTime - dRightAscension; const auto dLatitudeInRadians = latitude; - const auto dCos_Latitude = cos(dLatitudeInRadians); - const auto dSin_Latitude = sin(dLatitudeInRadians); - const auto dCos_HourAngle = cos(dHourAngle); + const auto dCosLatitude = cos(dLatitudeInRadians); + const auto dSinLatitude = sin(dLatitudeInRadians); + const auto dCosHourAngle = cos(dHourAngle); Direction2D udtSunCoordinates; udtSunCoordinates.y - = (acos(dCos_Latitude * dCos_HourAngle * cos(dDeclination) + sin(dDeclination) * dSin_Latitude)); - udtSunCoordinates.x = atan2(-sin(dHourAngle), tan(dDeclination) * dCos_Latitude - dSin_Latitude * dCos_HourAngle); + = (acos((dCosLatitude * dCosHourAngle * cos(dDeclination)) + (sin(dDeclination) * dSinLatitude))); + udtSunCoordinates.x = atan2(-sin(dHourAngle), (tan(dDeclination) * dCosLatitude) - (dSinLatitude * dCosHourAngle)); if (udtSunCoordinates.x < 0) { udtSunCoordinates.x = udtSunCoordinates.x + two_pi; } |