Introduce geodetic-geocentric conversions ... (#669)

* Introduce geodetic-geocentric conversions, as PJ_xxx style conversion step and as API entry points

* minor improvements and minor bug squashing

1 files changed, 56 insertions, 0 deletions

diff --git a/src/PJ_geoc.c b/src/PJ_geoc.c
new file mode 100644
index 00000000..865b1089
--- /dev/null
+++ b/src/PJ_geoc.c
@@ -0,0 +1,56 @@
+/******************************************************************************
+ * Project:  PROJ.4
+ * Purpose:  Conversion from geographic to geocentric latitude and back.
+ * Author:   Thomas Knudsen (2017)
+ *
+ ******************************************************************************
+ * Copyright (c) 2017, SDFE, http://www.sdfe.dk
+ * Copyright (c) 2017, Thomas Knudsen
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *****************************************************************************/
+
+#define PJ_LIB__
+#include <proj.h>
+#include <errno.h>
+#include "projects.h"
+
+PROJ_HEAD(geoc, "Geocentric Latitude");
+
+/* Geographical to geocentric */
+static PJ_COORD forward(PJ_COORD coo, PJ *P) {
+    return proj_geoc_lat (P, PJ_FWD, coo);
+}
+
+/* Geocentric to geographical */
+static PJ_COORD inverse(PJ_COORD coo, PJ *P) {
+    return proj_geoc_lat (P, PJ_INV, coo);
+}
+
+
+static PJ *CONVERSION(geoc, 1) {
+    P->inv4d = inverse;
+    P->fwd4d = forward;
+
+    P->left   =  PJ_IO_UNITS_RADIANS;
+    P->right  =  PJ_IO_UNITS_RADIANS;
+
+    P->is_latlong = 1;
+    return P;
+}