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authorKristian Evers <kristianevers@gmail.com>2018-12-26 10:53:01 +0100
committerGitHub <noreply@github.com>2018-12-26 10:53:01 +0100
commit81ec8c0b58d66333fccd3703dab62a11132a0331 (patch)
tree41b4675d169f849516649700ab4f50d4cffa4c02 /src/projections/gall.cpp
parent355d681ed88019e97742344bd642c2fd97e700a1 (diff)
parent80dad6ef2bed4a83008db06986dc168918d48476 (diff)
downloadPROJ-81ec8c0b58d66333fccd3703dab62a11132a0331.tar.gz
PROJ-81ec8c0b58d66333fccd3703dab62a11132a0331.zip
Merge pull request #1203 from rouault/cpp_conversion
Conversion of most C files to C++
Diffstat (limited to 'src/projections/gall.cpp')
-rw-r--r--src/projections/gall.cpp44
1 files changed, 44 insertions, 0 deletions
diff --git a/src/projections/gall.cpp b/src/projections/gall.cpp
new file mode 100644
index 00000000..a8697482
--- /dev/null
+++ b/src/projections/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;
+}