1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/intl/icu/source/i18n/astro.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,755 @@
1.4 +/************************************************************************
1.5 + * Copyright (C) 1996-2008, International Business Machines Corporation *
1.6 + * and others. All Rights Reserved. *
1.7 + ************************************************************************
1.8 + * 2003-nov-07 srl Port from Java
1.9 + */
1.10 +
1.11 +#ifndef ASTRO_H
1.12 +#define ASTRO_H
1.13 +
1.14 +#include "unicode/utypes.h"
1.15 +
1.16 +#if !UCONFIG_NO_FORMATTING
1.17 +
1.18 +#include "gregoimp.h" // for Math
1.19 +#include "unicode/unistr.h"
1.20 +
1.21 +U_NAMESPACE_BEGIN
1.22 +
1.23 +/**
1.24 + * <code>CalendarAstronomer</code> is a class that can perform the calculations to
1.25 + * determine the positions of the sun and moon, the time of sunrise and
1.26 + * sunset, and other astronomy-related data. The calculations it performs
1.27 + * are in some cases quite complicated, and this utility class saves you
1.28 + * the trouble of worrying about them.
1.29 + * <p>
1.30 + * The measurement of time is a very important part of astronomy. Because
1.31 + * astronomical bodies are constantly in motion, observations are only valid
1.32 + * at a given moment in time. Accordingly, each <code>CalendarAstronomer</code>
1.33 + * object has a <code>time</code> property that determines the date
1.34 + * and time for which its calculations are performed. You can set and
1.35 + * retrieve this property with {@link #setDate setDate}, {@link #getDate getDate}
1.36 + * and related methods.
1.37 + * <p>
1.38 + * Almost all of the calculations performed by this class, or by any
1.39 + * astronomer, are approximations to various degrees of accuracy. The
1.40 + * calculations in this class are mostly modelled after those described
1.41 + * in the book
1.42 + * <a href="http://www.amazon.com/exec/obidos/ISBN=0521356997" target="_top">
1.43 + * Practical Astronomy With Your Calculator</a>, by Peter J.
1.44 + * Duffett-Smith, Cambridge University Press, 1990. This is an excellent
1.45 + * book, and if you want a greater understanding of how these calculations
1.46 + * are performed it a very good, readable starting point.
1.47 + * <p>
1.48 + * <strong>WARNING:</strong> This class is very early in its development, and
1.49 + * it is highly likely that its API will change to some degree in the future.
1.50 + * At the moment, it basically does just enough to support {@link IslamicCalendar}
1.51 + * and {@link ChineseCalendar}.
1.52 + *
1.53 + * @author Laura Werner
1.54 + * @author Alan Liu
1.55 + * @internal
1.56 + */
1.57 +class U_I18N_API CalendarAstronomer : public UMemory {
1.58 +public:
1.59 + // some classes
1.60 +
1.61 +public:
1.62 + /**
1.63 + * Represents the position of an object in the sky relative to the ecliptic,
1.64 + * the plane of the earth's orbit around the Sun.
1.65 + * This is a spherical coordinate system in which the latitude
1.66 + * specifies the position north or south of the plane of the ecliptic.
1.67 + * The longitude specifies the position along the ecliptic plane
1.68 + * relative to the "First Point of Aries", which is the Sun's position in the sky
1.69 + * at the Vernal Equinox.
1.70 + * <p>
1.71 + * Note that Ecliptic objects are immutable and cannot be modified
1.72 + * once they are constructed. This allows them to be passed and returned by
1.73 + * value without worrying about whether other code will modify them.
1.74 + *
1.75 + * @see CalendarAstronomer.Equatorial
1.76 + * @see CalendarAstronomer.Horizon
1.77 + * @internal
1.78 + */
1.79 + class U_I18N_API Ecliptic : public UMemory {
1.80 + public:
1.81 + /**
1.82 + * Constructs an Ecliptic coordinate object.
1.83 + * <p>
1.84 + * @param lat The ecliptic latitude, measured in radians.
1.85 + * @param lon The ecliptic longitude, measured in radians.
1.86 + * @internal
1.87 + */
1.88 + Ecliptic(double lat = 0, double lon = 0) {
1.89 + latitude = lat;
1.90 + longitude = lon;
1.91 + }
1.92 +
1.93 + /**
1.94 + * Setter for Ecliptic Coordinate object
1.95 + * @param lat The ecliptic latitude, measured in radians.
1.96 + * @param lon The ecliptic longitude, measured in radians.
1.97 + * @internal
1.98 + */
1.99 + void set(double lat, double lon) {
1.100 + latitude = lat;
1.101 + longitude = lon;
1.102 + }
1.103 +
1.104 + /**
1.105 + * Return a string representation of this object
1.106 + * @internal
1.107 + */
1.108 + UnicodeString toString() const;
1.109 +
1.110 + /**
1.111 + * The ecliptic latitude, in radians. This specifies an object's
1.112 + * position north or south of the plane of the ecliptic,
1.113 + * with positive angles representing north.
1.114 + * @internal
1.115 + */
1.116 + double latitude;
1.117 +
1.118 + /**
1.119 + * The ecliptic longitude, in radians.
1.120 + * This specifies an object's position along the ecliptic plane
1.121 + * relative to the "First Point of Aries", which is the Sun's position
1.122 + * in the sky at the Vernal Equinox,
1.123 + * with positive angles representing east.
1.124 + * <p>
1.125 + * A bit of trivia: the first point of Aries is currently in the
1.126 + * constellation Pisces, due to the precession of the earth's axis.
1.127 + * @internal
1.128 + */
1.129 + double longitude;
1.130 + };
1.131 +
1.132 + /**
1.133 + * Represents the position of an
1.134 + * object in the sky relative to the plane of the earth's equator.
1.135 + * The <i>Right Ascension</i> specifies the position east or west
1.136 + * along the equator, relative to the sun's position at the vernal
1.137 + * equinox. The <i>Declination</i> is the position north or south
1.138 + * of the equatorial plane.
1.139 + * <p>
1.140 + * Note that Equatorial objects are immutable and cannot be modified
1.141 + * once they are constructed. This allows them to be passed and returned by
1.142 + * value without worrying about whether other code will modify them.
1.143 + *
1.144 + * @see CalendarAstronomer.Ecliptic
1.145 + * @see CalendarAstronomer.Horizon
1.146 + * @internal
1.147 + */
1.148 + class U_I18N_API Equatorial : public UMemory {
1.149 + public:
1.150 + /**
1.151 + * Constructs an Equatorial coordinate object.
1.152 + * <p>
1.153 + * @param asc The right ascension, measured in radians.
1.154 + * @param dec The declination, measured in radians.
1.155 + * @internal
1.156 + */
1.157 + Equatorial(double asc = 0, double dec = 0)
1.158 + : ascension(asc), declination(dec) { }
1.159 +
1.160 + /**
1.161 + * Setter
1.162 + * @param asc The right ascension, measured in radians.
1.163 + * @param dec The declination, measured in radians.
1.164 + * @internal
1.165 + */
1.166 + void set(double asc, double dec) {
1.167 + ascension = asc;
1.168 + declination = dec;
1.169 + }
1.170 +
1.171 + /**
1.172 + * Return a string representation of this object, with the
1.173 + * angles measured in degrees.
1.174 + * @internal
1.175 + */
1.176 + UnicodeString toString() const;
1.177 +
1.178 + /**
1.179 + * Return a string representation of this object with the right ascension
1.180 + * measured in hours, minutes, and seconds.
1.181 + * @internal
1.182 + */
1.183 + //String toHmsString() {
1.184 + //return radToHms(ascension) + "," + radToDms(declination);
1.185 + //}
1.186 +
1.187 + /**
1.188 + * The right ascension, in radians.
1.189 + * This is the position east or west along the equator
1.190 + * relative to the sun's position at the vernal equinox,
1.191 + * with positive angles representing East.
1.192 + * @internal
1.193 + */
1.194 + double ascension;
1.195 +
1.196 + /**
1.197 + * The declination, in radians.
1.198 + * This is the position north or south of the equatorial plane,
1.199 + * with positive angles representing north.
1.200 + * @internal
1.201 + */
1.202 + double declination;
1.203 + };
1.204 +
1.205 + /**
1.206 + * Represents the position of an object in the sky relative to
1.207 + * the local horizon.
1.208 + * The <i>Altitude</i> represents the object's elevation above the horizon,
1.209 + * with objects below the horizon having a negative altitude.
1.210 + * The <i>Azimuth</i> is the geographic direction of the object from the
1.211 + * observer's position, with 0 representing north. The azimuth increases
1.212 + * clockwise from north.
1.213 + * <p>
1.214 + * Note that Horizon objects are immutable and cannot be modified
1.215 + * once they are constructed. This allows them to be passed and returned by
1.216 + * value without worrying about whether other code will modify them.
1.217 + *
1.218 + * @see CalendarAstronomer.Ecliptic
1.219 + * @see CalendarAstronomer.Equatorial
1.220 + * @internal
1.221 + */
1.222 + class U_I18N_API Horizon : public UMemory {
1.223 + public:
1.224 + /**
1.225 + * Constructs a Horizon coordinate object.
1.226 + * <p>
1.227 + * @param alt The altitude, measured in radians above the horizon.
1.228 + * @param azim The azimuth, measured in radians clockwise from north.
1.229 + * @internal
1.230 + */
1.231 + Horizon(double alt=0, double azim=0)
1.232 + : altitude(alt), azimuth(azim) { }
1.233 +
1.234 + /**
1.235 + * Setter for Ecliptic Coordinate object
1.236 + * @param alt The altitude, measured in radians above the horizon.
1.237 + * @param azim The azimuth, measured in radians clockwise from north.
1.238 + * @internal
1.239 + */
1.240 + void set(double alt, double azim) {
1.241 + altitude = alt;
1.242 + azimuth = azim;
1.243 + }
1.244 +
1.245 + /**
1.246 + * Return a string representation of this object, with the
1.247 + * angles measured in degrees.
1.248 + * @internal
1.249 + */
1.250 + UnicodeString toString() const;
1.251 +
1.252 + /**
1.253 + * The object's altitude above the horizon, in radians.
1.254 + * @internal
1.255 + */
1.256 + double altitude;
1.257 +
1.258 + /**
1.259 + * The object's direction, in radians clockwise from north.
1.260 + * @internal
1.261 + */
1.262 + double azimuth;
1.263 + };
1.264 +
1.265 +public:
1.266 + //-------------------------------------------------------------------------
1.267 + // Assorted private data used for conversions
1.268 + //-------------------------------------------------------------------------
1.269 +
1.270 + // My own copies of these so compilers are more likely to optimize them away
1.271 + static const double PI;
1.272 +
1.273 + /**
1.274 + * The average number of solar days from one new moon to the next. This is the time
1.275 + * it takes for the moon to return the same ecliptic longitude as the sun.
1.276 + * It is longer than the sidereal month because the sun's longitude increases
1.277 + * during the year due to the revolution of the earth around the sun.
1.278 + * Approximately 29.53.
1.279 + *
1.280 + * @see #SIDEREAL_MONTH
1.281 + * @internal
1.282 + * @deprecated ICU 2.4. This class may be removed or modified.
1.283 + */
1.284 + static const double SYNODIC_MONTH;
1.285 +
1.286 + //-------------------------------------------------------------------------
1.287 + // Constructors
1.288 + //-------------------------------------------------------------------------
1.289 +
1.290 + /**
1.291 + * Construct a new <code>CalendarAstronomer</code> object that is initialized to
1.292 + * the current date and time.
1.293 + * @internal
1.294 + */
1.295 + CalendarAstronomer();
1.296 +
1.297 + /**
1.298 + * Construct a new <code>CalendarAstronomer</code> object that is initialized to
1.299 + * the specified date and time.
1.300 + * @internal
1.301 + */
1.302 + CalendarAstronomer(UDate d);
1.303 +
1.304 + /**
1.305 + * Construct a new <code>CalendarAstronomer</code> object with the given
1.306 + * latitude and longitude. The object's time is set to the current
1.307 + * date and time.
1.308 + * <p>
1.309 + * @param longitude The desired longitude, in <em>degrees</em> east of
1.310 + * the Greenwich meridian.
1.311 + *
1.312 + * @param latitude The desired latitude, in <em>degrees</em>. Positive
1.313 + * values signify North, negative South.
1.314 + *
1.315 + * @see java.util.Date#getTime()
1.316 + * @internal
1.317 + */
1.318 + CalendarAstronomer(double longitude, double latitude);
1.319 +
1.320 + /**
1.321 + * Destructor
1.322 + * @internal
1.323 + */
1.324 + ~CalendarAstronomer();
1.325 +
1.326 + //-------------------------------------------------------------------------
1.327 + // Time and date getters and setters
1.328 + //-------------------------------------------------------------------------
1.329 +
1.330 + /**
1.331 + * Set the current date and time of this <code>CalendarAstronomer</code> object. All
1.332 + * astronomical calculations are performed based on this time setting.
1.333 + *
1.334 + * @param aTime the date and time, expressed as the number of milliseconds since
1.335 + * 1/1/1970 0:00 GMT (Gregorian).
1.336 + *
1.337 + * @see #setDate
1.338 + * @see #getTime
1.339 + * @internal
1.340 + */
1.341 + void setTime(UDate aTime);
1.342 +
1.343 +
1.344 + /**
1.345 + * Set the current date and time of this <code>CalendarAstronomer</code> object. All
1.346 + * astronomical calculations are performed based on this time setting.
1.347 + *
1.348 + * @param aTime the date and time, expressed as the number of milliseconds since
1.349 + * 1/1/1970 0:00 GMT (Gregorian).
1.350 + *
1.351 + * @see #getTime
1.352 + * @internal
1.353 + */
1.354 + void setDate(UDate aDate) { setTime(aDate); }
1.355 +
1.356 + /**
1.357 + * Set the current date and time of this <code>CalendarAstronomer</code> object. All
1.358 + * astronomical calculations are performed based on this time setting.
1.359 + *
1.360 + * @param jdn the desired time, expressed as a "julian day number",
1.361 + * which is the number of elapsed days since
1.362 + * 1/1/4713 BC (Julian), 12:00 GMT. Note that julian day
1.363 + * numbers start at <em>noon</em>. To get the jdn for
1.364 + * the corresponding midnight, subtract 0.5.
1.365 + *
1.366 + * @see #getJulianDay
1.367 + * @see #JULIAN_EPOCH_MS
1.368 + * @internal
1.369 + */
1.370 + void setJulianDay(double jdn);
1.371 +
1.372 + /**
1.373 + * Get the current time of this <code>CalendarAstronomer</code> object,
1.374 + * represented as the number of milliseconds since
1.375 + * 1/1/1970 AD 0:00 GMT (Gregorian).
1.376 + *
1.377 + * @see #setTime
1.378 + * @see #getDate
1.379 + * @internal
1.380 + */
1.381 + UDate getTime();
1.382 +
1.383 + /**
1.384 + * Get the current time of this <code>CalendarAstronomer</code> object,
1.385 + * expressed as a "julian day number", which is the number of elapsed
1.386 + * days since 1/1/4713 BC (Julian), 12:00 GMT.
1.387 + *
1.388 + * @see #setJulianDay
1.389 + * @see #JULIAN_EPOCH_MS
1.390 + * @internal
1.391 + */
1.392 + double getJulianDay();
1.393 +
1.394 + /**
1.395 + * Return this object's time expressed in julian centuries:
1.396 + * the number of centuries after 1/1/1900 AD, 12:00 GMT
1.397 + *
1.398 + * @see #getJulianDay
1.399 + * @internal
1.400 + */
1.401 + double getJulianCentury();
1.402 +
1.403 + /**
1.404 + * Returns the current Greenwich sidereal time, measured in hours
1.405 + * @internal
1.406 + */
1.407 + double getGreenwichSidereal();
1.408 +
1.409 +private:
1.410 + double getSiderealOffset();
1.411 +public:
1.412 + /**
1.413 + * Returns the current local sidereal time, measured in hours
1.414 + * @internal
1.415 + */
1.416 + double getLocalSidereal();
1.417 +
1.418 + /**
1.419 + * Converts local sidereal time to Universal Time.
1.420 + *
1.421 + * @param lst The Local Sidereal Time, in hours since sidereal midnight
1.422 + * on this object's current date.
1.423 + *
1.424 + * @return The corresponding Universal Time, in milliseconds since
1.425 + * 1 Jan 1970, GMT.
1.426 + */
1.427 + //private:
1.428 + double lstToUT(double lst);
1.429 +
1.430 + /**
1.431 + *
1.432 + * Convert from ecliptic to equatorial coordinates.
1.433 + *
1.434 + * @param ecliptic The ecliptic
1.435 + * @param result Fillin result
1.436 + * @return reference to result
1.437 + */
1.438 + Equatorial& eclipticToEquatorial(Equatorial& result, const Ecliptic& ecliptic);
1.439 +
1.440 + /**
1.441 + * Convert from ecliptic to equatorial coordinates.
1.442 + *
1.443 + * @param eclipLong The ecliptic longitude
1.444 + * @param eclipLat The ecliptic latitude
1.445 + *
1.446 + * @return The corresponding point in equatorial coordinates.
1.447 + * @internal
1.448 + */
1.449 + Equatorial& eclipticToEquatorial(Equatorial& result, double eclipLong, double eclipLat);
1.450 +
1.451 + /**
1.452 + * Convert from ecliptic longitude to equatorial coordinates.
1.453 + *
1.454 + * @param eclipLong The ecliptic longitude
1.455 + *
1.456 + * @return The corresponding point in equatorial coordinates.
1.457 + * @internal
1.458 + */
1.459 + Equatorial& eclipticToEquatorial(Equatorial& result, double eclipLong) ;
1.460 +
1.461 + /**
1.462 + * @internal
1.463 + */
1.464 + Horizon& eclipticToHorizon(Horizon& result, double eclipLong) ;
1.465 +
1.466 + //-------------------------------------------------------------------------
1.467 + // The Sun
1.468 + //-------------------------------------------------------------------------
1.469 +
1.470 + /**
1.471 + * The longitude of the sun at the time specified by this object.
1.472 + * The longitude is measured in radians along the ecliptic
1.473 + * from the "first point of Aries," the point at which the ecliptic
1.474 + * crosses the earth's equatorial plane at the vernal equinox.
1.475 + * <p>
1.476 + * Currently, this method uses an approximation of the two-body Kepler's
1.477 + * equation for the earth and the sun. It does not take into account the
1.478 + * perturbations caused by the other planets, the moon, etc.
1.479 + * @internal
1.480 + */
1.481 + double getSunLongitude();
1.482 +
1.483 + /**
1.484 + * TODO Make this public when the entire class is package-private.
1.485 + */
1.486 + /*public*/ void getSunLongitude(double julianDay, double &longitude, double &meanAnomaly);
1.487 +
1.488 + /**
1.489 + * The position of the sun at this object's current date and time,
1.490 + * in equatorial coordinates.
1.491 + * @param result fillin for the result
1.492 + * @internal
1.493 + */
1.494 + Equatorial& getSunPosition(Equatorial& result);
1.495 +
1.496 +public:
1.497 + /**
1.498 + * Constant representing the vernal equinox.
1.499 + * For use with {@link #getSunTime getSunTime}.
1.500 + * Note: In this case, "vernal" refers to the northern hemisphere's seasons.
1.501 + * @internal
1.502 + */
1.503 +// static double VERNAL_EQUINOX();
1.504 +
1.505 + /**
1.506 + * Constant representing the summer solstice.
1.507 + * For use with {@link #getSunTime getSunTime}.
1.508 + * Note: In this case, "summer" refers to the northern hemisphere's seasons.
1.509 + * @internal
1.510 + */
1.511 + static double SUMMER_SOLSTICE();
1.512 +
1.513 + /**
1.514 + * Constant representing the autumnal equinox.
1.515 + * For use with {@link #getSunTime getSunTime}.
1.516 + * Note: In this case, "autumn" refers to the northern hemisphere's seasons.
1.517 + * @internal
1.518 + */
1.519 +// static double AUTUMN_EQUINOX();
1.520 +
1.521 + /**
1.522 + * Constant representing the winter solstice.
1.523 + * For use with {@link #getSunTime getSunTime}.
1.524 + * Note: In this case, "winter" refers to the northern hemisphere's seasons.
1.525 + * @internal
1.526 + */
1.527 + static double WINTER_SOLSTICE();
1.528 +
1.529 + /**
1.530 + * Find the next time at which the sun's ecliptic longitude will have
1.531 + * the desired value.
1.532 + * @internal
1.533 + */
1.534 + UDate getSunTime(double desired, UBool next);
1.535 +
1.536 + /**
1.537 + * Returns the time (GMT) of sunrise or sunset on the local date to which
1.538 + * this calendar is currently set.
1.539 + *
1.540 + * NOTE: This method only works well if this object is set to a
1.541 + * time near local noon. Because of variations between the local
1.542 + * official time zone and the geographic longitude, the
1.543 + * computation can flop over into an adjacent day if this object
1.544 + * is set to a time near local midnight.
1.545 + *
1.546 + * @internal
1.547 + */
1.548 + UDate getSunRiseSet(UBool rise);
1.549 +
1.550 + //-------------------------------------------------------------------------
1.551 + // The Moon
1.552 + //-------------------------------------------------------------------------
1.553 +
1.554 + /**
1.555 + * The position of the moon at the time set on this
1.556 + * object, in equatorial coordinates.
1.557 + * @internal
1.558 + * @return const reference to internal field of calendar astronomer. Do not use outside of the lifetime of this astronomer.
1.559 + */
1.560 + const Equatorial& getMoonPosition();
1.561 +
1.562 + /**
1.563 + * The "age" of the moon at the time specified in this object.
1.564 + * This is really the angle between the
1.565 + * current ecliptic longitudes of the sun and the moon,
1.566 + * measured in radians.
1.567 + *
1.568 + * @see #getMoonPhase
1.569 + * @internal
1.570 + */
1.571 + double getMoonAge();
1.572 +
1.573 + /**
1.574 + * Calculate the phase of the moon at the time set in this object.
1.575 + * The returned phase is a <code>double</code> in the range
1.576 + * <code>0 <= phase < 1</code>, interpreted as follows:
1.577 + * <ul>
1.578 + * <li>0.00: New moon
1.579 + * <li>0.25: First quarter
1.580 + * <li>0.50: Full moon
1.581 + * <li>0.75: Last quarter
1.582 + * </ul>
1.583 + *
1.584 + * @see #getMoonAge
1.585 + * @internal
1.586 + */
1.587 + double getMoonPhase();
1.588 +
1.589 + class U_I18N_API MoonAge : public UMemory {
1.590 + public:
1.591 + MoonAge(double l)
1.592 + : value(l) { }
1.593 + void set(double l) { value = l; }
1.594 + double value;
1.595 + };
1.596 +
1.597 + /**
1.598 + * Constant representing a new moon.
1.599 + * For use with {@link #getMoonTime getMoonTime}
1.600 + * @internal
1.601 + */
1.602 + static const MoonAge NEW_MOON();
1.603 +
1.604 + /**
1.605 + * Constant representing the moon's first quarter.
1.606 + * For use with {@link #getMoonTime getMoonTime}
1.607 + * @internal
1.608 + */
1.609 +// static const MoonAge FIRST_QUARTER();
1.610 +
1.611 + /**
1.612 + * Constant representing a full moon.
1.613 + * For use with {@link #getMoonTime getMoonTime}
1.614 + * @internal
1.615 + */
1.616 + static const MoonAge FULL_MOON();
1.617 +
1.618 + /**
1.619 + * Constant representing the moon's last quarter.
1.620 + * For use with {@link #getMoonTime getMoonTime}
1.621 + * @internal
1.622 + */
1.623 +// static const MoonAge LAST_QUARTER();
1.624 +
1.625 + /**
1.626 + * Find the next or previous time at which the Moon's ecliptic
1.627 + * longitude will have the desired value.
1.628 + * <p>
1.629 + * @param desired The desired longitude.
1.630 + * @param next <tt>true</tt> if the next occurrance of the phase
1.631 + * is desired, <tt>false</tt> for the previous occurrance.
1.632 + * @internal
1.633 + */
1.634 + UDate getMoonTime(double desired, UBool next);
1.635 + UDate getMoonTime(const MoonAge& desired, UBool next);
1.636 +
1.637 + /**
1.638 + * Returns the time (GMT) of sunrise or sunset on the local date to which
1.639 + * this calendar is currently set.
1.640 + * @internal
1.641 + */
1.642 + UDate getMoonRiseSet(UBool rise);
1.643 +
1.644 + //-------------------------------------------------------------------------
1.645 + // Interpolation methods for finding the time at which a given event occurs
1.646 + //-------------------------------------------------------------------------
1.647 +
1.648 + // private
1.649 + class AngleFunc : public UMemory {
1.650 + public:
1.651 + virtual double eval(CalendarAstronomer&) = 0;
1.652 + virtual ~AngleFunc();
1.653 + };
1.654 + friend class AngleFunc;
1.655 +
1.656 + UDate timeOfAngle(AngleFunc& func, double desired,
1.657 + double periodDays, double epsilon, UBool next);
1.658 +
1.659 + class CoordFunc : public UMemory {
1.660 + public:
1.661 + virtual void eval(Equatorial& result, CalendarAstronomer&) = 0;
1.662 + virtual ~CoordFunc();
1.663 + };
1.664 + friend class CoordFunc;
1.665 +
1.666 + double riseOrSet(CoordFunc& func, UBool rise,
1.667 + double diameter, double refraction,
1.668 + double epsilon);
1.669 +
1.670 + //-------------------------------------------------------------------------
1.671 + // Other utility methods
1.672 + //-------------------------------------------------------------------------
1.673 +private:
1.674 +
1.675 + /**
1.676 + * Return the obliquity of the ecliptic (the angle between the ecliptic
1.677 + * and the earth's equator) at the current time. This varies due to
1.678 + * the precession of the earth's axis.
1.679 + *
1.680 + * @return the obliquity of the ecliptic relative to the equator,
1.681 + * measured in radians.
1.682 + */
1.683 + double eclipticObliquity();
1.684 +
1.685 + //-------------------------------------------------------------------------
1.686 + // Private data
1.687 + //-------------------------------------------------------------------------
1.688 +private:
1.689 + /**
1.690 + * Current time in milliseconds since 1/1/1970 AD
1.691 + * @see java.util.Date#getTime
1.692 + */
1.693 + UDate fTime;
1.694 +
1.695 + /* These aren't used yet, but they'll be needed for sunset calculations
1.696 + * and equatorial to horizon coordinate conversions
1.697 + */
1.698 + double fLongitude;
1.699 + double fLatitude;
1.700 + double fGmtOffset;
1.701 +
1.702 + //
1.703 + // The following fields are used to cache calculated results for improved
1.704 + // performance. These values all depend on the current time setting
1.705 + // of this object, so the clearCache method is provided.
1.706 + //
1.707 +
1.708 + double julianDay;
1.709 + double julianCentury;
1.710 + double sunLongitude;
1.711 + double meanAnomalySun;
1.712 + double moonLongitude;
1.713 + double moonEclipLong;
1.714 + double meanAnomalyMoon;
1.715 + double eclipObliquity;
1.716 + double siderealT0;
1.717 + double siderealTime;
1.718 +
1.719 + void clearCache();
1.720 +
1.721 + Equatorial moonPosition;
1.722 + UBool moonPositionSet;
1.723 +
1.724 + /**
1.725 + * @internal
1.726 + */
1.727 +// UDate local(UDate localMillis);
1.728 +};
1.729 +
1.730 +U_NAMESPACE_END
1.731 +
1.732 +struct UHashtable;
1.733 +
1.734 +U_NAMESPACE_BEGIN
1.735 +
1.736 +/**
1.737 + * Cache of month -> julian day
1.738 + * @internal
1.739 + */
1.740 +class CalendarCache : public UMemory {
1.741 +public:
1.742 + static int32_t get(CalendarCache** cache, int32_t key, UErrorCode &status);
1.743 + static void put(CalendarCache** cache, int32_t key, int32_t value, UErrorCode &status);
1.744 + virtual ~CalendarCache();
1.745 +private:
1.746 + CalendarCache(int32_t size, UErrorCode& status);
1.747 + static void createCache(CalendarCache** cache, UErrorCode& status);
1.748 + /**
1.749 + * not implemented
1.750 + */
1.751 + CalendarCache();
1.752 + UHashtable *fTable;
1.753 +};
1.754 +
1.755 +U_NAMESPACE_END
1.756 +
1.757 +#endif
1.758 +#endif
