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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/boggs.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/boggs.cpp')
-rw-r--r--src/projections/boggs.cpp43
1 files changed, 43 insertions, 0 deletions
diff --git a/src/projections/boggs.cpp b/src/projections/boggs.cpp
new file mode 100644
index 00000000..119357c0
--- /dev/null
+++ b/src/projections/boggs.cpp
@@ -0,0 +1,43 @@
+#define PJ_LIB__
+#include <math.h>
+
+#include "projects.h"
+
+PROJ_HEAD(boggs, "Boggs Eumorphic") "\n\tPCyl, no inv, Sph";
+# define NITER 20
+# define EPS 1e-7
+# define FXC 2.00276
+# define FXC2 1.11072
+# define FYC 0.49931
+
+
+static XY s_forward (LP lp, PJ *P) { /* Spheroidal, forward */
+ XY xy = {0.0,0.0};
+ double theta, th1, c;
+ int i;
+ (void) P;
+
+ theta = lp.phi;
+ if (fabs(fabs(lp.phi) - M_HALFPI) < EPS)
+ xy.x = 0.;
+ else {
+ c = sin(theta) * M_PI;
+ for (i = NITER; i; --i) {
+ theta -= th1 = (theta + sin(theta) - c) /
+ (1. + cos(theta));
+ if (fabs(th1) < EPS) break;
+ }
+ theta *= 0.5;
+ xy.x = FXC * lp.lam / (1. / cos(lp.phi) + FXC2 / cos(theta));
+ }
+ xy.y = FYC * (lp.phi + M_SQRT2 * sin(theta));
+ return (xy);
+}
+
+
+
+PJ *PROJECTION(boggs) {
+ P->es = 0.;
+ P->fwd = s_forward;
+ return P;
+}