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authorEven Rouault <even.rouault@spatialys.com>2018-12-19 12:25:33 +0100
committerEven Rouault <even.rouault@spatialys.com>2018-12-26 10:08:54 +0100
commite6de172371ea203f6393d745641d66c82b5b13e2 (patch)
tree791fa07f431a2d1db6f6e813ab984db982587278 /src/projections/PJ_eck1.cpp
parentce8075076b4e4ffebd32afaba419e1d9ab27cd03 (diff)
downloadPROJ-e6de172371ea203f6393d745641d66c82b5b13e2.tar.gz
PROJ-e6de172371ea203f6393d745641d66c82b5b13e2.zip
cpp conversion: move source files in apps/ iso19111/ conversions/ projections/ transformations/ tests/ subdirectories
Diffstat (limited to 'src/projections/PJ_eck1.cpp')
-rw-r--r--src/projections/PJ_eck1.cpp41
1 files changed, 41 insertions, 0 deletions
diff --git a/src/projections/PJ_eck1.cpp b/src/projections/PJ_eck1.cpp
new file mode 100644
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--- /dev/null
+++ b/src/projections/PJ_eck1.cpp
@@ -0,0 +1,41 @@
+#define PJ_LIB__
+#include <math.h>
+
+#include "projects.h"
+
+PROJ_HEAD(eck1, "Eckert I") "\n\tPCyl, Sph";
+#define FC 0.92131773192356127802
+#define RP 0.31830988618379067154
+
+
+static XY s_forward (LP lp, PJ *P) { /* Spheroidal, forward */
+ XY xy = {0.0,0.0};
+ (void) P;
+
+ xy.x = FC * lp.lam * (1. - RP * fabs(lp.phi));
+ xy.y = FC * lp.phi;
+
+ return xy;
+}
+
+
+static LP s_inverse (XY xy, PJ *P) { /* Spheroidal, inverse */
+ LP lp = {0.0,0.0};
+ (void) P;
+
+ lp.phi = xy.y / FC;
+ lp.lam = xy.x / (FC * (1. - RP * fabs(lp.phi)));
+
+ return (lp);
+}
+
+
+
+PJ *PROJECTION(eck1) {
+ P->es = 0.0;
+ P->inv = s_inverse;
+ P->fwd = s_forward;
+
+ return P
+;
+}