diff options
Diffstat (limited to 'src/projections/hammer.cpp')
| -rw-r--r-- | src/projections/hammer.cpp | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/src/projections/hammer.cpp b/src/projections/hammer.cpp index aa7d1ba9..56bdf74e 100644 --- a/src/projections/hammer.cpp +++ b/src/projections/hammer.cpp @@ -19,19 +19,26 @@ struct pj_opaque { } // anonymous namespace -static PJ_XY s_forward (PJ_LP lp, PJ *P) { /* Spheroidal, forward */ +static PJ_XY hammer_s_forward (PJ_LP lp, PJ *P) { /* Spheroidal, forward */ PJ_XY xy = {0.0,0.0}; struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque); double cosphi, d; - d = sqrt(2./(1. + (cosphi = cos(lp.phi)) * cos(lp.lam *= Q->w))); + cosphi = cos(lp.phi); + lp.lam *= Q->w; + double denom = 1. + cosphi * cos(lp.lam); + if( denom == 0.0 ) { + proj_errno_set(P, PJD_ERR_TOLERANCE_CONDITION); + return proj_coord_error().xy; + } + d = sqrt(2./denom); xy.x = Q->m * d * cosphi * sin(lp.lam); xy.y = Q->rm * d * sin(lp.phi); return xy; } -static PJ_LP s_inverse (PJ_XY xy, PJ *P) { /* Spheroidal, inverse */ +static PJ_LP hammer_s_inverse (PJ_XY xy, PJ *P) { /* Spheroidal, inverse */ PJ_LP lp = {0.0,0.0}; struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque); double z; @@ -70,8 +77,8 @@ PJ *PROJECTION(hammer) { Q->m /= Q->w; P->es = 0.; - P->fwd = s_forward; - P->inv = s_inverse; + P->fwd = hammer_s_forward; + P->inv = hammer_s_inverse; return P; } |