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diff --git a/src/ext/plantuml/com/ctreber/acearth/util/SunPositionCalculator.java b/src/ext/plantuml/com/ctreber/acearth/util/SunPositionCalculator.java
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--- a/src/ext/plantuml/com/ctreber/acearth/util/SunPositionCalculator.java
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@@ -1,260 +0,0 @@
-package ext.plantuml.com.ctreber.acearth.util;
-
-import java.util.Calendar;
-import java.util.Date;
-import java.util.TimeZone;
-
-/**
- * <p>Calculates the position of the point on Earth which is directly
- * below the sun or the moon.
- *
- * <p>&copy; 2002 Christian Treber, ct@ctreber.com
- * @author Christian Treber, ct@ctreber.com
- *
- */
-public class SunPositionCalculator
-{
- /*
- * the epoch upon which these astronomical calculations are based is
- * 1990 january 0.0, 631065600 seconds since the beginning of the
- * "unix epoch" (00:00:00 GMT, Jan. 1, 1970)
- *
- * given a number of seconds since the start of the unix epoch,
- * daysSinceEpoch() computes the number of days since the start of the
- * astronomical epoch (1990 january 0.0)
- */
-
- private static final long EPOCH_START = 631065600000l;
-
- /*
- * assuming the apparent orbit of the sun about the earth is circular,
- * the rate at which the orbit progresses is given by RadsPerDay --
- * TWOPI radians per orbit divided by 365.242191 days per year:
- */
-
- private static final double RADS_PER_DAY = Toolkit.TWOPI / 365.242191;
-
- /*
- * details of sun's apparent orbit at epoch 1990.0 (after
- * duffett-smith, table 6, section 46)
- *
- * Epsilon_g (ecliptic longitude at epoch 1990.0) 279.403303 degrees
- * OmegaBar_g (ecliptic longitude of perigee) 282.768422 degrees
- * Eccentricity (eccentricity of orbit) 0.016713
- */
-
- private static final double EPSILON_G = Toolkit.degsToRads(279.403303);
- private static final double OMEGA_BAR_G = Toolkit.degsToRads(282.768422);
- private static final double ECCENTRICITY = 0.016713;
-
- /*
- * Lunar parameters, epoch January 0, 1990.0
- */
- private static final double MOON_MEAN_LONGITUDE = Toolkit.degsToRads(318.351648);
- private static final double MOON_MEAN_LONGITUDE_PERIGEE = Toolkit.degsToRads(36.340410);
- private static final double MOON_MEAN_LONGITUDE_NODE = Toolkit.degsToRads(318.510107);
- private static final double MOON_INCLINATION = Toolkit.degsToRads(5.145396);
-
- private static final double SIDERAL_MONTH = 27.3217;
-
- /**
- * <p>Calculate the position of the mean sun: where the sun would
- * be if the earth's orbit were circular instead of ellipictal.
- *
- * <p>Verified.
- *
- * @param pDays days since ephemeris epoch
- */
- private static double getMeanSunLongitude(double pDays)
- {
- double N, M;
-
- N = RADS_PER_DAY * pDays;
- N = Toolkit.fmod(N, 0, Toolkit.TWOPI);
- if(N < 0)
- {
- N += Toolkit.TWOPI;
- }
-
- M = N + EPSILON_G - OMEGA_BAR_G;
- if(M < 0)
- {
- M += Toolkit.TWOPI;
- }
-
- return M;
- }
-
- /**
- * <p>Compute ecliptic longitude of sun (in radians)
- * (after duffett-smith, section 47)
- *
- * <p>Verified.
- *
- * @param pMillis Milliseconds since unix epoch
- */
- private static double getSunEclipticLongitude(long pMillis)
- {
- final double lDays = daysSinceEpoch(pMillis);
- final double M_sun = getMeanSunLongitude(lDays);
-
- final double E = doKepler(M_sun);
- final double v = 2 * Math.atan(Math.sqrt((1 + ECCENTRICITY) / (1 - ECCENTRICITY)) * Math.tan(E / 2));
-
- return (v + OMEGA_BAR_G);
- }
-
- static double daysSinceEpoch(long pMillis)
- {
- return (double)(pMillis - EPOCH_START) / 24 / 3600 / 1000;
- }
-
- /**
- * solve Kepler's equation via Newton's method
- * (after duffett-smith, section 47)
- *
- * <p>Verified.
- */
- private static double doKepler(double M)
- {
- double E;
- double lDelta;
-
- E = M;
- while(true)
- {
- lDelta = E - ECCENTRICITY * Math.sin(E) - M;
- if(Math.abs(lDelta) <= 1e-10)
- {
- break;
- }
- E -= lDelta / (1 - ECCENTRICITY * Math.cos(E));
- }
-
- return E;
- }
-
-
- /**
- * <p>computing julian dates (assuming gregorian calendar, thus this is
- * only valid for dates of 1582 oct 15 or later)
- * (after duffett-smith, section 4)
- *
- * <p>Verified.
- *
- * @param pYear year (e.g. 19xx)
- * @param pMonth month (jan=1, feb=2, ...)
- * @param pDay day of month
- */
- private static double getJulianDate(int pYear, int pMonth, int pDay)
- {
- if((pMonth == 1) || (pMonth == 2))
- {
- pYear -= 1;
- pMonth += 12;
- }
-
- final int A = pYear / 100;
- final int B = 2 - A + (A / 4);
- final int C = (int)(365.25 * pYear);
- final int D = (int)(30.6001 * (pMonth + 1));
-
- return B + C + D + pDay + 1720994.5;
- }
-
-
- /**
- * <p>compute greenwich mean sidereal time (getGST) corresponding to a given
- * number of milliseconds since the unix epoch
- * (after duffett-smith, section 12)
- *
- * <p>Verified.
- */
- private static double getGST(long pMillis)
- {
- final Calendar lCal = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
- lCal.setTime(new Date(pMillis));
-
- final double lJulianDate = getJulianDate(lCal.get(Calendar.YEAR), lCal.get(Calendar.MONTH) + 1,
- lCal.get(Calendar.DAY_OF_MONTH));
- final double T = (lJulianDate - 2451545) / 36525;
- double T0 = ((T + 2.5862e-5) * T + 2400.051336) * T + 6.697374558;
-
- T0 = Toolkit.fmod(T0, 0, 24.0);
- if(T0 < 0)
- {
- T0 += 24;
- }
-
- final double UT = lCal.get(Calendar.HOUR_OF_DAY) +
- (lCal.get(Calendar.MINUTE) + lCal.get(Calendar.SECOND) / 60.0) / 60.0;
-
- T0 += UT * 1.002737909;
- T0 = Toolkit.fmod(T0, 0, 24.0);
- if(T0 < 0)
- {
- T0 += 24;
- }
-
- return T0;
- }
-
- /**
- * <p>Given a particular time (expressed in milliseconds since the unix
- * epoch), compute position on the earth (lat, lon) such that sun is
- * directly overhead.
- *
- * <p>Verified.
- *
- * @param pMillis seconds since unix epoch
- *
- */
- public static Coordinate getSunPositionOnEarth(long pMillis)
- {
- final Coordinate lSunPosEc = new Coordinate(0.0, getSunEclipticLongitude(pMillis));
- final Coordinate lSunPosEq = lSunPosEc.eclipticToEquatorial();
-
- final double lRA = Toolkit.limitRads(lSunPosEq.getRA() - (Toolkit.TWOPI / 24) * getGST(pMillis));
-
- return new Coordinate(Toolkit.radsToDegs(lSunPosEq.getDE()), Toolkit.radsToDegs(lRA));
- }
-
- /**
- * <p>Given a particular time (expressed in milliseconds since the unix
- * epoch), compute position on the earth (lat, lon) such that the
- * moon is directly overhead.
- *
- * Based on duffett-smith **2nd ed** section 61; combines some steps
- * into single expressions to reduce the number of extra variables.
- *
- * <p>Verified.
- */
- public static Coordinate getMoonPositionOnEarth(long pMillis)
- {
- final double lDays = daysSinceEpoch(pMillis);
- double lSunLongEc = getSunEclipticLongitude(pMillis);
- final double Ms = getMeanSunLongitude(lDays);
-
- double L = Toolkit.limitRads(Toolkit.fmod(lDays / SIDERAL_MONTH, 0, 1.0) * Toolkit.TWOPI + MOON_MEAN_LONGITUDE);
- double Mm = Toolkit.limitRads(L - Toolkit.degsToRads(0.1114041 * lDays) - MOON_MEAN_LONGITUDE_PERIGEE);
- double N = Toolkit.limitRads(MOON_MEAN_LONGITUDE_NODE - Toolkit.degsToRads(0.0529539 * lDays));
- final double Ev = Toolkit.degsToRads(1.2739) * Math.sin(2.0 * (L - lSunLongEc) - Mm);
- final double Ae = Toolkit.degsToRads(0.1858) * Math.sin(Ms);
- Mm += Ev - Ae - Toolkit.degsToRads(0.37) * Math.sin(Ms);
- final double Ec = Toolkit.degsToRads(6.2886) * Math.sin(Mm);
- L += Ev + Ec - Ae + Toolkit.degsToRads(0.214) * Math.sin(2.0 * Mm);
- L += Toolkit.degsToRads(0.6583) * Math.sin(2.0 * (L - lSunLongEc));
- N -= Toolkit.degsToRads(0.16) * Math.sin(Ms);
-
- L -= N;
- lSunLongEc = Toolkit.limitRads((Math.abs(Math.cos(L)) < 1e-12) ?
- (N + Math.sin(L) * Math.cos(MOON_INCLINATION) * Math.PI / 2) :
- (N + Math.atan2(Math.sin(L) * Math.cos(MOON_INCLINATION), Math.cos(L))));
- final double lSunLatEc = Math.asin(Math.sin(L) * Math.sin(MOON_INCLINATION));
-
- final Coordinate lSunPosEq = new Coordinate(lSunLatEc, lSunLongEc).eclipticToEquatorial();
- final double lRA = Toolkit.limitRads(lSunPosEq.getRA() - (Toolkit.TWOPI / 24) * getGST(pMillis));
-
- return new Coordinate(Toolkit.radsToDegs(lSunPosEq.getDE()), Toolkit.radsToDegs(lRA));
- }
-}
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