diff options
Diffstat (limited to 'src/projections/lsat.cpp')
| -rw-r--r-- | src/projections/lsat.cpp | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/src/projections/lsat.cpp b/src/projections/lsat.cpp index 5b7520d3..f6114485 100644 --- a/src/projections/lsat.cpp +++ b/src/projections/lsat.cpp @@ -44,7 +44,7 @@ static void seraz0(double lam, double mult, PJ *P) { } -static PJ_XY e_forward (PJ_LP lp, PJ *P) { /* Ellipsoidal, forward */ +static PJ_XY lsat_e_forward (PJ_LP lp, PJ *P) { /* Ellipsoidal, forward */ PJ_XY xy = {0.0,0.0}; struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque); int l, nn; @@ -107,12 +107,11 @@ static PJ_XY e_forward (PJ_LP lp, PJ *P) { /* Ellipsoidal, forward */ } -static PJ_LP e_inverse (PJ_XY xy, PJ *P) { /* Ellipsoidal, inverse */ +static PJ_LP lsat_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); 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; @@ -205,8 +208,8 @@ PJ *PROJECTION(lsat) { Q->c1 /= 15.; Q->c3 /= 45.; - P->inv = e_inverse; - P->fwd = e_forward; + P->inv = lsat_e_inverse; + P->fwd = lsat_e_forward; return P; } |