aboutsummaryrefslogtreecommitdiff
path: root/src/projections/hammer.cpp
diff options
context:
space:
mode:
authorEven Rouault <even.rouault@spatialys.com>2018-12-19 13:00:37 +0100
committerEven Rouault <even.rouault@spatialys.com>2018-12-26 10:08:55 +0100
commitdf574ae332d57f556fd56314883b3354cab1d0ff (patch)
tree63a68d40d7ed7932d6329d9c7baa340bb6294f7f /src/projections/hammer.cpp
parente6de172371ea203f6393d745641d66c82b5b13e2 (diff)
downloadPROJ-df574ae332d57f556fd56314883b3354cab1d0ff.tar.gz
PROJ-df574ae332d57f556fd56314883b3354cab1d0ff.zip
cpp conversion: remove useless pj_, PJ_ and proj_ filename prefixes
Diffstat (limited to 'src/projections/hammer.cpp')
-rw-r--r--src/projections/hammer.cpp77
1 files changed, 77 insertions, 0 deletions
diff --git a/src/projections/hammer.cpp b/src/projections/hammer.cpp
new file mode 100644
index 00000000..d4caa656
--- /dev/null
+++ b/src/projections/hammer.cpp
@@ -0,0 +1,77 @@
+#define PJ_LIB__
+
+#include <errno.h>
+#include <math.h>
+
+#include "proj.h"
+#include "projects.h"
+
+PROJ_HEAD(hammer, "Hammer & Eckert-Greifendorff")
+ "\n\tMisc Sph, \n\tW= M=";
+
+#define EPS 1.0e-10
+
+namespace { // anonymous namespace
+struct pj_opaque {
+ double w;
+ double m, rm;
+};
+} // anonymous namespace
+
+
+static XY s_forward (LP lp, PJ *P) { /* Spheroidal, forward */
+ 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)));
+ xy.x = Q->m * d * cosphi * sin(lp.lam);
+ xy.y = Q->rm * d * sin(lp.phi);
+ return xy;
+}
+
+
+static LP s_inverse (XY xy, PJ *P) { /* Spheroidal, inverse */
+ LP lp = {0.0,0.0};
+ struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
+ double z;
+
+ z = sqrt(1. - 0.25*Q->w*Q->w*xy.x*xy.x - 0.25*xy.y*xy.y);
+ if (fabs(2.*z*z-1.) < EPS) {
+ lp.lam = HUGE_VAL;
+ lp.phi = HUGE_VAL;
+ proj_errno_set(P, PJD_ERR_LAT_OR_LON_EXCEED_LIMIT);
+ } else {
+ lp.lam = aatan2(Q->w * xy.x * z,2. * z * z - 1)/Q->w;
+ lp.phi = aasin(P->ctx,z * xy.y);
+ }
+ return lp;
+}
+
+
+PJ *PROJECTION(hammer) {
+ struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
+ if (nullptr==Q)
+ return pj_default_destructor (P, ENOMEM);
+ P->opaque = Q;
+
+ if (pj_param(P->ctx, P->params, "tW").i) {
+ if ((Q->w = fabs(pj_param(P->ctx, P->params, "dW").f)) <= 0.)
+ return pj_default_destructor (P, PJD_ERR_W_OR_M_ZERO_OR_LESS);
+ } else
+ Q->w = .5;
+ if (pj_param(P->ctx, P->params, "tM").i) {
+ if ((Q->m = fabs(pj_param(P->ctx, P->params, "dM").f)) <= 0.)
+ return pj_default_destructor (P, PJD_ERR_W_OR_M_ZERO_OR_LESS);
+ } else
+ Q->m = 1.;
+
+ Q->rm = 1. / Q->m;
+ Q->m /= Q->w;
+
+ P->es = 0.;
+ P->fwd = s_forward;
+ P->inv = s_inverse;
+
+ return P;
+}