StelUtils.hpp

/*
 * Stellarium
 * Copyright (C) 2002 Fabien Chereau
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA  02110-1335, USA.
 */

#ifndef _STELUTILS_HPP_
#define _STELUTILS_HPP_

#include "VecMath.hpp"

#include <QVariantMap>
#include <QDateTime>
#include <QSize>
#include <QString>

// astonomical unit (km)
#define AU 149597870.691
// Parsec (km)
#define PARSEC 30.857e12
// speed of light (km/sec)
#define SPEED_OF_LIGHT 299792.458

namespace StelUtils
{
    QString getApplicationName();

    QString getApplicationVersion();

    double hmsToRad(const unsigned int h, const unsigned int m, const double s);

    double dmsToRad(const int d, const unsigned int m, const double s);

    void radToHms(double rad, unsigned int& h, unsigned int& m, double& s);

    void radToDms(double rad, bool& sign, unsigned int& d, unsigned int& m, double& s);

    QString radToHmsStrAdapt(const double angle);

    QString radToHmsStr(const double angle, const bool decimal=false);

    QString radToDmsStrAdapt(const double angle, const bool useD=false);

    QString radToDmsStr(const double angle, const bool decimal=false, const bool useD=false);

    double dmsStrToRad(const QString& s);

    Vec3f strToVec3f(const QStringList& s);
    Vec3f strToVec3f(const QString& s);

    QString vec3fToHtmlColor(const Vec3f& v);

    Vec3f htmlColorToVec3f(const QString& c);

    void spheToRect(const double lng, const double lat, Vec3d& v);

    void spheToRect(const float lng, const float lat, Vec3f& v);

    void rectToSphe(double *lng, double *lat, const Vec3d& v);

    void rectToSphe(float *lng, float *lat, const Vec3d& v);

    void rectToSphe(float *lng, float *lat, const Vec3f& v);

    // GZ: some additions. I need those just for quick conversions for text display.
    void ctRadec2Ecl(const double raRad, const double decRad, const double eclRad, double *lambdaRad, double *betaRad);
    // GZ: done

    double getDecAngle(const QString& str);

    bool isPowerOfTwo(const int value);

    int smallestPowerOfTwoGreaterOrEqualTo(const int value);

    QSize smallestPowerOfTwoSizeGreaterOrEqualTo(const QSize base);

    double asinh(const double z);

    // New Qt based General Calendar Functions.
    void getDateFromJulianDay(const double julianDay, int *year, int *month, int *day);

    void getTimeFromJulianDay(const double julianDay, int *hour, int *minute, int *second);

    bool getDateTimeFromISO8601String(const QString& iso8601Date, int* y, int* m, int* d, int* h, int* min, float* s);
    
    QString julianDayToISO8601String(const double jd);

    double getJulianDayFromISO8601String(const QString& iso8601Date, bool* ok);
    
    QString localeDateString(const int year, const int month, const int day, const int dayOfWeek, const QString fmt);

    QString localeDateString(const int year, const int month, const int day, const int dayOfWeek);

    double getJDFromSystem();

    double qTimeToJDFraction(const QTime& time);

    QTime jdFractionToQTime(const double jd);

    float getGMTShiftFromQT(const double jd);

    double qDateTimeToJd(const QDateTime& dateTime);

    QDateTime jdToQDateTime(const double& jd);

    bool getJDFromDate(double* newjd, const int y, const int m, const int d, const int h, const int min, const int s);

    int numberOfDaysInMonthInYear(const int month, const int year);
    bool changeDateTimeForRollover(int oy, int om, int od, int oh, int omin, int os,
                    int* ry, int* rm, int* rd, int* rh, int* rmin, int* rs);

    void debugQVariantMap(const QVariant& m, const QString& indent="", const QString& key="");


    inline float fastAcos(const float x)
    {
        return M_PI_2 - (x + x*x*x * (1.f/6.f + x*x * (3.f/40.f + 5.f/112.f * x*x)) );
    }

    inline float fastExp(const float x)
    {
        return (x>=0)?
            (1.f + x*(1.f+ x/2.f*(1.f+ x/3.f*(1.f+x/4.f*(1.f+x/5.f))))):
                1.f / (1.f -x*(1.f -x/2.f*(1.f- x/3.f*(1.f-x/4.f*(1.f-x/5.f)))));
    }

    inline Vec3f getNightColor(const Vec3f& dayColor)
    {
        float max = 0.0;
        for(int i=0; i<3; i++)
        {
            max = dayColor[i] > max ? dayColor[i] : max;
        }
        return Vec3f(max, 0, 0);
    }

    double calculateSiderealPeriod(const double SemiMajorAxis);

    QString hoursToHmsStr(const double hours);

    long double secondsSinceStart();

    // GZ: I don't see this returning 0. There is always a rough estimate beyond that.
    double getDeltaTByEspenakMeeus(const double jDay);

    double getDeltaTBySchoch(const double jDay);

    double getDeltaTByClemence(const double jDay);

    double getDeltaTByIAU(const double jDay);

    double getDeltaTByAstronomicalEphemeris(const double jDay);

    double getDeltaTByTuckermanGoldstine(const double jDay);

    double getDeltaTByMullerStephenson(const double jDay);

    double getDeltaTByStephenson1978(const double jDay);

    double getDeltaTByStephenson1997(const double jDay);

    double getDeltaTBySchmadelZech1979(const double jDay);

    double getDeltaTByMorrisonStephenson1982(const double jDay);

    double getDeltaTByStephensonMorrison1984(const double jDay);

    double getDeltaTByStephensonMorrison1995(const double jDay);

    double getDeltaTByStephensonHoulden(const double jDay);

    double getDeltaTByEspenak(const double jDay);

    double getDeltaTByBorkowski(const double jDay);

    double getDeltaTBySchmadelZech1988(const double jDay);

    double getDeltaTByChaprontTouze(const double jDay); 

    double getDeltaTByJPLHorizons(const double jDay);

    double getDeltaTByMorrisonStephenson2004(const double jDay);

    double getDeltaTByReijs(const double jDay);

    double getDeltaTByChaprontMeeus(const double jDay);

    double getDeltaTByMeeusSimons(const double jDay);

    double getDeltaTByMontenbruckPfleger(const double jDay);

    double getDeltaTByReingoldDershowitz(const double jDay);

    double getDeltaTByBanjevic(const double jDay);

    double getDeltaTByIslamSadiqQureshi(const double jDay);

    double getMoonSecularAcceleration(const double jDay, const double ndot);

    double getDeltaTStandardError(const double jDay);
}

#endif // _STELUTILS_HPP_