diff options
Diffstat (limited to 'src/projections/lsat.cpp')
| -rw-r--r-- | src/projections/lsat.cpp | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/src/projections/lsat.cpp b/src/projections/lsat.cpp index 5b7520d3..f9eec1b9 100644 --- a/src/projections/lsat.cpp +++ b/src/projections/lsat.cpp @@ -112,7 +112,6 @@ static PJ_LP e_inverse (PJ_XY xy, PJ *P) { /* Ellipsoidal, inverse */ struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque); int nn; double lamt, sdsq, s, lamdp, phidp, sppsq, dd, sd, sl, fac, scl, sav, spp; - lamdp = xy.x / Q->b; nn = 50; do { @@ -135,10 +134,14 @@ static PJ_LP e_inverse (PJ_XY xy, PJ *P) { /* Ellipsoidal, inverse */ lamdp -= TOL; spp = sin(phidp); sppsq = spp * spp; + const double denom = 1. - sppsq * (1. + Q->u); + if( denom == 0.0 ) { + proj_errno_set(P, PJD_ERR_INVALID_X_OR_Y); + return proj_coord_error().lp; + } lamt = atan(((1. - sppsq * P->rone_es) * tan(lamdp) * Q->ca - spp * Q->sa * sqrt((1. + Q->q * dd) * ( - 1. - sppsq) - sppsq * Q->u) / cos(lamdp)) / (1. - sppsq - * (1. + Q->u))); + 1. - sppsq) - sppsq * Q->u) / cos(lamdp)) / denom); sl = lamt >= 0. ? 1. : -1.; scl = cos(lamdp) >= 0. ? 1. : -1; lamt -= M_HALFPI * (1. - scl) * sl; |