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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_gall.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_gall.cpp')
-rw-r--r--src/projections/PJ_gall.cpp44
1 files changed, 44 insertions, 0 deletions
diff --git a/src/projections/PJ_gall.cpp b/src/projections/PJ_gall.cpp
new file mode 100644
index 00000000..a8697482
--- /dev/null
+++ b/src/projections/PJ_gall.cpp
@@ -0,0 +1,44 @@
+#define PJ_LIB__
+
+#include <math.h>
+
+#include "projects.h"
+
+PROJ_HEAD(gall, "Gall (Gall Stereographic)") "\n\tCyl, Sph";
+
+#define YF 1.70710678118654752440
+#define XF 0.70710678118654752440
+#define RYF 0.58578643762690495119
+#define RXF 1.41421356237309504880
+
+
+static XY s_forward (LP lp, PJ *P) { /* Spheroidal, forward */
+ XY xy = {0.0,0.0};
+ (void) P;
+
+ xy.x = XF * lp.lam;
+ xy.y = YF * tan(.5 * lp.phi);
+
+ return xy;
+}
+
+
+static LP s_inverse (XY xy, PJ *P) { /* Spheroidal, inverse */
+ LP lp = {0.0,0.0};
+ (void) P;
+
+ lp.lam = RXF * xy.x;
+ lp.phi = 2. * atan(xy.y * RYF);
+
+ return lp;
+}
+
+
+PJ *PROJECTION(gall) {
+ P->es = 0.0;
+
+ P->inv = s_inverse;
+ P->fwd = s_forward;
+
+ return P;
+}