pj_krovak.cpp

projapi是一个关于GIS行业投影转换的程序库

#include "stdafx.h"


#define PROJ_PARMS__ \
	double	C_x;
#define PJ_LIB__

#include "projects.h"

#include <string.h>
#include <stdio.h>
#include <math.h>

PJ_CVSID("$Id: PJ_krovak.c,v 1.4 2002/12/15 22:31:04 warmerda Exp $");	

PROJ_HEAD(krovak, "Krovak") "\n\tPCyl., Sph.";

/**
   NOTES: According to EPSG the full Krovak projection method should have
          the following parameters.  Within PROJ.4 the azimuth, and pseudo
          standard parallel are hardcoded in the algorithm and can't be 
          altered from outside.  The others all have defaults to match the
          common usage with Krovak projection.

  lat_0 = latitude of centre of the projection
         
  lon_0 = longitude of centre of the projection
  
  ** = azimuth (true) of the centre line passing through the centre of the projection

  ** = latitude of pseudo standard parallel
   
  k  = scale factor on the pseudo standard parallel
  
  x_0 = False Easting of the centre of the projection at the apex of the cone
  
  y_0 = False Northing of the centre of the projection at the apex of the cone

 **/



FORWARD(s_forward); /* spheroid */
/* calculate xy from lat/lon */

	char errmess[255];
	char tmp[16];

/* Constants, identical to inverse transform function */
	double s45, s90, e2, e, alfa, uq, u0, g, k, k1, n0, ro0, ad, a, s0, n;
	double gfi, u, fi0, lon17, lamdd, deltav, s, d, eps, ro;


	s45 = 0.785398163397448;    /* 45