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authorEven Rouault <even.rouault@spatialys.com>2018-12-18 20:24:11 +0100
committerEven Rouault <even.rouault@spatialys.com>2018-12-26 10:08:53 +0100
commit610957f7035242f15743c399ffd429b92bc36206 (patch)
tree73f0d51147e2f4860c4bfc875f7a4bf9359386d4 /src/pj_auth.cpp
parent355d681ed88019e97742344bd642c2fd97e700a1 (diff)
downloadPROJ-610957f7035242f15743c399ffd429b92bc36206.tar.gz
PROJ-610957f7035242f15743c399ffd429b92bc36206.zip
cpp conversion: minimal steps to fix compilation errors, not warnings
Diffstat (limited to 'src/pj_auth.cpp')
-rw-r--r--src/pj_auth.cpp36
1 files changed, 36 insertions, 0 deletions
diff --git a/src/pj_auth.cpp b/src/pj_auth.cpp
new file mode 100644
index 00000000..d6024671
--- /dev/null
+++ b/src/pj_auth.cpp
@@ -0,0 +1,36 @@
+/* determine latitude from authalic latitude */
+
+#include <math.h>
+#include <stddef.h>
+
+#include "projects.h"
+
+# define P00 .33333333333333333333 /* 1 / 3 */
+# define P01 .17222222222222222222 /* 31 / 180 */
+# define P02 .10257936507936507937 /* 517 / 5040 */
+# define P10 .06388888888888888888 /* 23 / 360 */
+# define P11 .06640211640211640212 /* 251 / 3780 */
+# define P20 .01677689594356261023 /* 761 / 45360 */
+#define APA_SIZE 3
+
+ double *
+pj_authset(double es) {
+ double t, *APA;
+
+ if ((APA = (double *)pj_malloc(APA_SIZE * sizeof(double))) != NULL) {
+ APA[0] = es * P00;
+ t = es * es;
+ APA[0] += t * P01;
+ APA[1] = t * P10;
+ t *= es;
+ APA[0] += t * P02;
+ APA[1] += t * P11;
+ APA[2] = t * P20;
+ }
+ return APA;
+}
+ double
+pj_authlat(double beta, double *APA) {
+ double t = beta+beta;
+ return(beta + APA[0] * sin(t) + APA[1] * sin(t+t) + APA[2] * sin(t+t+t));
+}