text: /*
  ** libproj -- library of cartographic projections
  **
  ** Copyright (c) 2003, 2006   Gerald I. Evenden
  */
  static const char
  LIBPROJ_ID[] = "$Id$";
  /*
  ** Permission is hereby granted, free of charge, to any person obtaining
  ** a copy of this software and associated documentation files (the
  ** "Software"), to deal in the Software without restriction, including
  ** without limitation the rights to use, copy, modify, merge, publish,
  ** distribute, sublicense, and/or sell copies of the Software, and to
  ** permit persons to whom the Software is furnished to do so, subject to
  ** the following conditions:
  **
  ** The above copyright notice and this permission notice shall be
  ** included in all copies or substantial portions of the Software.
  **
  ** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  ** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  ** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  ** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  ** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  ** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  ** SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
  #define PROJ_PARMS__ \
    double  esp; \
    double  ml0; \
    void  *en;
  #define PROJ_LIB__
  #include  <lib_proj.h>
  PROJ_HEAD(tmerc, "Transverse Mercator") "\n\tCyl, Sph&Ell";
  PROJ_HEAD(utm, "Universal Transverse Mercator (UTM)")
    "\n\tCyl, Sph\n\tzone= south";
  #define EPS10  1.e-10
  #define aks0  P->esp
  #define aks5  P->ml0
  #define FC1 1.
  #define FC2 .5
  #define FC3 .16666666666666666666
  #define FC4 .08333333333333333333
  #define FC5 .05
  #define FC6 .03333333333333333333
  #define FC7 .02380952380952380952
  #define FC8 .01785714285714285714
  FORWARD(e_forward); /* ellipse */
    double al, als, n, cosphi, sinphi, t;
  
    sinphi = sin(lp.phi); cosphi = cos(lp.phi);
    t = fabs(cosphi) > 1e-10 ? sinphi/cosphi : 0.;
    t *= t;
    al = cosphi * lp.lam;
    als = al * al;
    al /= sqrt(1. - P->es * sinphi * sinphi);
    n = P->esp * cosphi * cosphi;
    xy.x = P->k0 * al * (FC1 +
      FC3 * als * (1. - t + n +
      FC5 * als * (5. + t * (t - 18.) + n * (14. - 58. * t +
       n * (13. - 64. * t + n * (4. - 24 * t)))
      + FC7 * als * (61. + t * ( t * (179. - t) - 479. ) )
      )));
    xy.y = P->k0 * (proj_mdist(lp.phi, sinphi, cosphi, P->en) - P->ml0 +
      sinphi * al * lp.lam * FC2 * ( 1. +
      FC4 * als * (5. - t + n * (9. + 4. * n) +
      FC6 * als * (61. + t * (t - 58.) + n * (270. - 330 * t +
       n * (445. - 680. * t + n * (324. - 600. * t + n * (88. - 192. * t))))
      + FC8 * als * (1385. + t * ( t * (543. - t) - 3111.) )
      ))));
    return (xy);
  }
  FORWARD(s_forward); /* sphere */
    double b, cosphi;
  
    b = (cosphi = cos(lp.phi)) * sin(lp.lam);
    if (fabs(fabs(b) - 1.) <= EPS10) F_ERROR;
    xy.x = aks5 * log((1. + b) / (1. - b));
    if ((b = fabs( xy.y = cosphi * cos(lp.lam) / sqrt(1. - b * b) )) >= 1.) {
      if ((b - 1.) > EPS10) F_ERROR
      else xy.y = 0.;
    } else
      xy.y = acos(xy.y);
    if (lp.phi < 0.) xy.y = -xy.y;
    xy.y = aks0 * (xy.y - P->phi0);
    return (xy);
  }
  INVERSE(e_inverse); /* ellipsoid */
    double n, con, cosphi, d, ds, sinphi, t;
  
    lp.phi = proj_inv_mdist(P->ml0 + xy.y / P->k0, P->en);
    if (fabs(lp.phi) >= HALFPI) {
      lp.phi = xy.y < 0. ? -HALFPI : HALFPI;
      lp.lam = 0.;
    } else {
      sinphi = sin(lp.phi);
      cosphi = cos(lp.phi);
      t = fabs(cosphi) > 1e-10 ? sinphi/cosphi : 0.;
      n = P->esp * cosphi * cosphi;
      d = xy.x * sqrt(con = 1. - P->es * sinphi * sinphi) / P->k0;
      con *= t;
      t *= t;
      ds = d * d;
      lp.phi -= (con * ds / (1.-P->es)) * FC2 * (1. -
        ds * FC4 * (5. + t * (3. - 9. *  n) + n * (1. - 4 * n) -
        ds * FC6*(61. + t*(90. - n*(252. + 90.*t) +
          45.*t) + n*(46. + n*(-3. + t*(-66. + 225.*t) +
          n*(100. + 84.*t + n*(88. - 192.*t))))
         - ds * FC8 * (1385. + t * (3633. + t * (4095. + 1574. * t)) )
        )));
      lp.lam = d*(FC1 -
        ds*FC3*( 1. + 2.*t + n -
        ds*FC5*(5. + t*(28. + 8.*n + 24.*t) + n * (6. + n*(- 3. +
           4.*t + n*(-4. + 24.*t)))
         - ds * FC7 * (61. + t * (662. + t * (1320. + 720. * t)) )
      ))) / cosphi;
    }
    return (lp);
  }
  INVERSE(s_inverse); /* sphere */
    double D = xy.y / aks0 + P->phi0, xp = xy.x / aks0;
  
    lp.phi = asin(sin(D) / cosh(xp));
    lp.lam = atan2(sinh(xp), cos(D));
    return (lp);
  }
  FREEUP;
    if (P) {
      if (P->en)
        free(P->en);
      free(P);
    }
  }
    static PROJ *
  setup(PROJ *P) { /* general initialization */
    if (P->es) {
      if (!((P->en = proj_mdist_ini(P->es))))
        E_ERROR_0;
      P->ml0 = proj_mdist(P->phi0, sin(P->phi0), cos(P->phi0), P->en);
      P->esp = P->es / (1. - P->es);
      P->inv = e_inverse;
      P->fwd = e_forward;
    } else {
      aks0 = P->k0;
      aks5 = .5 * aks0;
      P->inv = s_inverse;
      P->fwd = s_forward;
    }
    return P;
  }
  ENTRY1(tmerc, en)
  ENDENTRY(setup(P))
  ENTRY1(utm, en)
    int zone;
  
    if (!P->es) E_ERROR(-34);
    P->y0 = proj_param(P->params, "bsouth").i ? 10000000. : 0.;
    P->x0 = 500000.;
    if (proj_param(P->params, "tzone").i) /* zone input ? */
      if ((zone = proj_param(P->params, "izone").i) > 0 && zone <= 60)
        --zone;
      else
        E_ERROR(-35)
    else /* nearest central meridian input */
      if (((zone = (int)floor((proj_adjlon(P->lam0) + PI) * 30. / PI))) < 0)
        zone = 0;
      else if (zone >= 60)
        zone = 59;
    P->lam0 = (zone + .5) * PI / 30. - PI;
    P->k0 = 0.9996;
    P->phi0 = 0.;
  ENDENTRY(setup(P))
  /*
  ** $Log: proj_tmerc.c,v $
  ** Revision 3.2  2008/06/28 15:10:58  gie
  ** Corrected error in inverse.
  ** Updated precision to comply with USC&GS Sp. Pub. #251 and
  ** DMA publication DMATM 8358.2.
  ** Effects of both error correction and precision update are
  ** only noticeable in the mm range.
  **
  ** Revision 3.1  2006/01/11 01:38:18  gie
  ** Initial
  **
  */
  