从对象C调用无对象的特定C ++方法

Question

I need to calculate moon phase by calling a method TruePhase. Problem is that I work in Objective C and I need to call a method from C++ source that I don't understand so much. Could anybody tell me how to call C++ TruePhase method from Objective C?

moon.h

#if _MSC_VER > 1000
#pragma once
#endif

#ifndef __AAMOONPHASES_H__
#define __AAMOONPHASES_H__

#ifndef AAPLUS_EXT_CLASS
#define AAPLUS_EXT_CLASS
#endif

class AAPLUS_EXT_CLASS CAAMoonPhases
{
public:
//Static methods
  static double K(double Year);
  static double MeanPhase(double k);
  static double TruePhase(double k);
};

#endif //__AAMOONPHASES_H__

moon.cpp (moon.mm)

#include "stdafx.h"
#include "AAMoonPhases.h"
#include "AACoordinateTransformation.h"
#include <cmath>
#include <cassert>
using namespace std;

double CAAMoonPhases::K(double Year)
{
  return 12.3685*(Year - 2000);
}

double CAAMoonPhases::MeanPhase(double k)
{
  //convert from K to T
  double T = k/1236.85;
  double T2 = T*T;
  double T3 = T2*T;
  double T4 = T3*T;

  return 2451550.09766 + 29.530588861*k + 0.00015437*T2 - 0.000000150*T3 + 0.00000000073*T4;
}

double CAAMoonPhases::TruePhase(double k)
{
  //What will be the return value
  double JD = MeanPhase(k);

  //convert from K to T
  double T = k/1236.85;
  double T2 = T*T;
  double T3 = T2*T;
  double T4 = T3*T;

  double E = 1 - 0.002516*T - 0.0000074*T2;
  double E2 = E*E;

  double M = CAACoordinateTransformation::MapTo0To360Range(2.5534 + 29.10535670*k - 0.0000014*T2 - 0.00000011*T3);
  M = CAACoordinateTransformation::DegreesToRadians(M);
  double Mdash = CAACoordinateTransformation::MapTo0To360Range(201.5643 + 385.81693528*k + 0.0107582*T2 + 0.00001238*T3 - 0.000000058*T4); 
  Mdash = CAACoordinateTransformation::DegreesToRadians(Mdash);
  double F = CAACoordinateTransformation::MapTo0To360Range(160.7108 + 390.67050284*k - 0.0016118*T2 - 0.00000227*T3 + 0.000000011*T4);
  F = CAACoordinateTransformation::DegreesToRadians(F);
  double omega = CAACoordinateTransformation::MapTo0To360Range(124.7746 - 1.56375588*k + 0.0020672*T2 + 0.00000215*T3);
  omega = CAACoordinateTransformation::DegreesToRadians(omega);
  double A1 = CAACoordinateTransformation::MapTo0To360Range(299.77 + 0.107408*k - 0.009173*T2);
  A1 = CAACoordinateTransformation::DegreesToRadians(A1);
  double A2 = CAACoordinateTransformation::MapTo0To360Range(251.88 + 0.016321*k);
  A2 = CAACoordinateTransformation::DegreesToRadians(A2);
  double A3 = CAACoordinateTransformation::MapTo0To360Range(251.83 + 26.651886*k);
  A3 = CAACoordinateTransformation::DegreesToRadians(A3);
  double A4 = CAACoordinateTransformation::MapTo0To360Range(349.42 + 36.412478*k);
  A4 = CAACoordinateTransformation::DegreesToRadians(A4);
  double A5 = CAACoordinateTransformation::MapTo0To360Range(84.66 + 18.206239*k);
  A5 = CAACoordinateTransformation::DegreesToRadians(A5);
  double A6 = CAACoordinateTransformation::MapTo0To360Range(141.74 + 53.303771*k);
  A6 = CAACoordinateTransformation::DegreesToRadians(A6);
  double A7 = CAACoordinateTransformation::MapTo0To360Range(207.14 + 2.453732*k);
  A7 = CAACoordinateTransformation::DegreesToRadians(A7);
  double A8 = CAACoordinateTransformation::MapTo0To360Range(154.84 + 7.306860*k);
  A8 = CAACoordinateTransformation::DegreesToRadians(A8);
  double A9 = CAACoordinateTransformation::MapTo0To360Range(34.52 + 27.261239*k);
  A9 = CAACoordinateTransformation::DegreesToRadians(A9);
  double A10 = CAACoordinateTransformation::MapTo0To360Range(207.19 + 0.121824*k);
  A10 = CAACoordinateTransformation::DegreesToRadians(A10);
  double A11 = CAACoordinateTransformation::MapTo0To360Range(291.34 + 1.844379*k);
  A11 = CAACoordinateTransformation::DegreesToRadians(A11);
  double A12 = CAACoordinateTransformation::MapTo0To360Range(161.72 + 24.198154*k);
  A12 = CAACoordinateTransformation::DegreesToRadians(A12);
  double A13 = CAACoordinateTransformation::MapTo0To360Range(239.56 + 25.513099*k);
  A13 = CAACoordinateTransformation::DegreesToRadians(A13);
  double A14 = CAACoordinateTransformation::MapTo0To360Range(331.55 + 3.592518*k);
  A14 = CAACoordinateTransformation::DegreesToRadians(A14);

  //convert to radians
  double kint = 0;
  double kfrac = modf(k, &kint);
  if (kfrac < 0)
    kfrac = 1 + kfrac;
  if (kfrac == 0) //New Moon
  {
    double DeltaJD = -0.40720*sin(Mdash) +
          0.17241*E*sin(M) +
          0.01608*sin(2*Mdash) +
          0.01039*sin(2*F) +
          0.00739*E*sin(Mdash - M) +
          -0.00514*E*sin(Mdash + M) +
          0.00208*E2*sin(2*M) +
          -0.00111*sin(Mdash - 2*F) +
          -0.00057*sin(Mdash + 2*F) +
          0.00056*E*sin(2*Mdash + M) +
          -0.00042*sin(3*Mdash) +
          0.00042*E*sin(M + 2*F) +
          0.00038*E*sin(M - 2*F) +
          -0.00024*E*sin(2*Mdash - M) +
          -0.00017*sin(omega) +
          -0.00007*sin(Mdash + 2*M) +
          0.00004*sin(2*Mdash - 2*F) +
          0.00004*sin(3*M) +
          0.00003*sin(Mdash + M - 2*F) +
          0.00003*sin(2*Mdash + 2*F) +
          -0.00003*sin(Mdash + M + 2*F) +
          0.00003*sin(Mdash - M + 2*F) +
          -0.00002*sin(Mdash - M - 2*F) +
          -0.00002*sin(3*Mdash + M) +
          0.00002*sin(4*Mdash);
    JD += DeltaJD;
  }
  else if ((kfrac == 0.25) || (kfrac == 0.75)) //First Quarter or Last Quarter
  {
    double DeltaJD = -0.62801*sin(Mdash) +
          0.17172*E*sin(M) +
          -0.01183*E*sin(Mdash + M) +
          0.00862*sin(2*Mdash) +
          0.00804*sin(2*F) +
          0.00454*E*sin(Mdash - M) +
          0.00204*E2*sin(2*M) +
          -0.00180*sin(Mdash - 2*F) +
          -0.00070*sin(Mdash + 2*F) +
          -0.00040*sin(3*Mdash) +
          -0.00034*E*sin(2*Mdash - M) +
          0.00032*E*sin(M + 2*F) +
          0.00032*E*sin(M - 2*F) +
          -0.00028*E2*sin(Mdash + 2*M) +
          0.00027*E*sin(2*Mdash + M) +
          -0.00017*sin(omega) +
          -0.00005*sin(Mdash - M - 2*F) +
          0.00004*sin(2*Mdash + 2*F) +
          -0.00004*sin(Mdash + M + 2*F) +
          0.00004*sin(Mdash - 2*M) +
          0.00003*sin(Mdash + M - 2*F) +
          0.00003*sin(3*M) +
          0.00002*sin(2*Mdash - 2*F) +
          0.00002*sin(Mdash - M + 2*F) +
          -0.00002*sin(3*Mdash + M);
    JD += DeltaJD;

    double W = 0.00306 - 0.00038*E*cos(M) + 0.00026*cos(Mdash) - 0.00002*cos(Mdash - M) + 0.00002*cos(Mdash + M) + 0.00002*cos(2*F);
    if (kfrac == 0.25) //First quarter
      JD += W;
    else
      JD -= W;          
  }
  else if (kfrac == 0.5) //Full Moon
  {
    double DeltaJD = -0.40614*sin(Mdash) +
          0.17302*E*sin(M) +
          0.01614*sin(2*Mdash) +
          0.01043*sin(2*F) +
          0.00734*E*sin(Mdash - M) +
          -0.00514*E*sin(Mdash + M) +
          0.00209*E2*sin(2*M) +
          -0.00111*sin(Mdash - 2*F) +
          -0.00057*sin(Mdash + 2*F) +
          0.00056*E*sin(2*Mdash + M) +
          -0.00042*sin(3*Mdash) +
          0.00042*E*sin(M + 2*F) +
          0.00038*E*sin(M - 2*F) +
          -0.00024*E*sin(2*Mdash - M) +
          -0.00017*sin(omega) +
          -0.00007*sin(Mdash + 2*M) +
          0.00004*sin(2*Mdash - 2*F) +
          0.00004*sin(3*M) +
          0.00003*sin(Mdash + M - 2*F) +
          0.00003*sin(2*Mdash + 2*F) +
          -0.00003*sin(Mdash + M + 2*F) +
          0.00003*sin(Mdash - M + 2*F) +
          -0.00002*sin(Mdash - M - 2*F) +
          -0.00002*sin(3*Mdash + M) +
          0.00002*sin(4*Mdash);
    JD += DeltaJD;
  }
  else
  {
    assert(false);
  }

  //Additional corrections for all phases
  double DeltaJD2 = 0.000325*sin(A1) +
        0.000165*sin(A2) +
        0.000164*sin(A3) +
        0.000126*sin(A4) +
        0.000110*sin(A5) +
        0.000062*sin(A6) +
        0.000060*sin(A7) +
        0.000056*sin(A8) +
        0.000047*sin(A9) +
        0.000042*sin(A10) +
        0.000040*sin(A11) +
        0.000037*sin(A12) +
        0.000035*sin(A13) +
        0.000023*sin(A14);
  JD += DeltaJD2;

  return JD;
}

Answer 1

Rename your unit file from .m to .mm . MM files are compiled with Objective-C++ compiler. Include source file with #include "moon.h" somewhere at the top of your unit file. Call something like that within your viewDidLoad method:

- (void)viewDidLoad {
    [super viewDidLoad];

    double k = CAAMoonPhases::K(2015);
    double phase = CAAMoonPhases::TruePhase(k);

    NSLog(@"k = %f phase = %f", k, phase);
}

I didn't work much with AA+ so you'll have to figure out how to use CAAMoonPhases yourself, but I suppose my implementation is about right...