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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_collg.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_collg.cpp')
-rw-r--r--src/projections/PJ_collg.cpp53
1 files changed, 53 insertions, 0 deletions
diff --git a/src/projections/PJ_collg.cpp b/src/projections/PJ_collg.cpp
new file mode 100644
index 00000000..7904de29
--- /dev/null
+++ b/src/projections/PJ_collg.cpp
@@ -0,0 +1,53 @@
+#define PJ_LIB__
+
+#include <math.h>
+
+#include "proj.h"
+#include "projects.h"
+
+PROJ_HEAD(collg, "Collignon") "\n\tPCyl, Sph";
+#define FXC 1.12837916709551257390
+#define FYC 1.77245385090551602729
+#define ONEEPS 1.0000001
+
+
+static XY s_forward (LP lp, PJ *P) { /* Spheroidal, forward */
+ XY xy = {0.0,0.0};
+ (void) P;
+ if ((xy.y = 1. - sin(lp.phi)) <= 0.)
+ xy.y = 0.;
+ else
+ xy.y = sqrt(xy.y);
+ xy.x = FXC * lp.lam * xy.y;
+ xy.y = FYC * (1. - xy.y);
+ return (xy);
+}
+
+
+static LP s_inverse (XY xy, PJ *P) { /* Spheroidal, inverse */
+ LP lp = {0.0,0.0};
+ lp.phi = xy.y / FYC - 1.;
+ if (fabs(lp.phi = 1. - lp.phi * lp.phi) < 1.)
+ lp.phi = asin(lp.phi);
+ else if (fabs(lp.phi) > ONEEPS) {
+ proj_errno_set(P, PJD_ERR_TOLERANCE_CONDITION);
+ return lp;
+ } else {
+ lp.phi = lp.phi < 0. ? -M_HALFPI : M_HALFPI;
+ }
+
+ if ((lp.lam = 1. - sin(lp.phi)) <= 0.)
+ lp.lam = 0.;
+ else
+ lp.lam = xy.x / (FXC * sqrt(lp.lam));
+ return (lp);
+}
+
+
+PJ *PROJECTION(collg) {
+ P->es = 0.0;
+ P->inv = s_inverse;
+ P->fwd = s_forward;
+
+ return P;
+}