inline void inv(cartesian_type& xy_x, cartesian_type& xy_y, geographic_type& lp_lon, geographic_type& lp_lat) const
{
double theta, dr, S, dif;
int i;
xy_x /= this->m_par.k0;
xy_y /= this->m_par.k0;
theta = atan2(xy_x , this->m_proj_parm.r0 - xy_y);
dr = xy_y - xy_x * tan(0.5 * theta);
lp_lon = theta / this->m_proj_parm.l;
S = dr;
for (i = MAX_ITER; i ; --i) {
S -= (dif = (fS(S, this->m_proj_parm.C) - dr) / fSp(S, this->m_proj_parm.C));
if (fabs(dif) < DEL_TOL) break;
}
if (!i) throw proj_exception();
lp_lat = pj_inv_mlfn(S + this->m_proj_parm.M0, this->m_par.es, this->m_proj_parm.en);
}
static PJ_LP lcca_e_inverse (PJ_XY xy, PJ *P) { /* Ellipsoidal, inverse */
PJ_LP lp = {0.0,0.0};
struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
double theta, dr, S, dif;
int i;
xy.x /= P->k0;
xy.y /= P->k0;
theta = atan2(xy.x , Q->r0 - xy.y);
dr = xy.y - xy.x * tan(0.5 * theta);
lp.lam = theta / Q->l;
S = dr;
for (i = MAX_ITER; i ; --i) {
S -= (dif = (fS(S, Q->C) - dr) / fSp(S, Q->C));
if (fabs(dif) < DEL_TOL) break;
}
if (!i) {
proj_errno_set(P, PJD_ERR_TOLERANCE_CONDITION);
return lp;
}
lp.phi = pj_inv_mlfn(P->ctx, S + Q->M0, P->es, Q->en);
return lp;
}
