1 files changed, 102 insertions, 26 deletions
diff --git a/src/PJ_nell.c b/src/PJ_nell.c
index 77983de8..b69b9997 100644
--- a/src/PJ_nell.c
+++ b/src/PJ_nell.c
@@ -1,30 +1,106 @@
 #define PJ_LIB__
-#include	<projects.h>
+#include <projects.h>
+
 PROJ_HEAD(nell, "Nell") "\n\tPCyl., Sph.";
-#define MAX_ITER	10
-#define LOOP_TOL	1e-7
-FORWARD(s_forward); /* spheroid */
-	double k, V;
-	int i;
-	(void) P;
-
-	k = 2. * sin(lp.phi);
-	V = lp.phi * lp.phi;
-	lp.phi *= 1.00371 + V * (-0.0935382 + V * -0.011412);
-	for (i = MAX_ITER; i ; --i) {
-		lp.phi -= V = (lp.phi + sin(lp.phi) - k) /
-			(1. + cos(lp.phi));
-		if (fabs(V) < LOOP_TOL)
-			break;
-	}
-	xy.x = 0.5 * lp.lam * (1. + cos(lp.phi));
-	xy.y = lp.phi;
-	return (xy);
+
+#define MAX_ITER 10
+#define LOOP_TOL 1e-7
+
+
+static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
+    XY xy = {0.0,0.0};
+    double k, V;
+    int i;
+    (void) P;
+
+    k = 2. * sin(lp.phi);
+    V = lp.phi * lp.phi;
+    lp.phi *= 1.00371 + V * (-0.0935382 + V * -0.011412);
+    for (i = MAX_ITER; i ; --i) {
+        lp.phi -= V = (lp.phi + sin(lp.phi) - k) /
+            (1. + cos(lp.phi));
+        if (fabs(V) < LOOP_TOL)
+            break;
+    }
+    xy.x = 0.5 * lp.lam * (1. + cos(lp.phi));
+    xy.y = lp.phi;
+
+    return xy;
+}
+
+
+static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
+    LP lp = {0.0,0.0};
+    lp.lam = 2. * xy.x / (1. + cos(xy.y));
+    lp.phi = aasin(P->ctx,0.5 * (xy.y + sin(xy.y)));
+
+    return lp;
+}
+
+
+static void *freeup_new (PJ *P) {                       /* Destructor */
+    if (0==P)
+        return 0;
+
+    return pj_dealloc(P);
+}
+
+
+static void freeup (PJ *P) {
+    freeup_new (P);
+    return;
+}
+
+
+PJ *PROJECTION(nell) {
+
+    P->es = 0;
+    P->inv = s_inverse;
+    P->fwd = s_forward;
+
+    return P;
 }
-INVERSE(s_inverse); /* spheroid */
-	lp.lam = 2. * xy.x / (1. + cos(xy.y));
-	lp.phi = aasin(P->ctx,0.5 * (xy.y + sin(xy.y)));
-	return (lp);
+
+#ifdef PJ_OMIT_SELFTEST
+int pj_nell_selftest (void) {return 0;}
+#else
+
+int pj_nell_selftest (void) {
+    double tolerance_lp = 1e-10;
+    double tolerance_xy = 1e-7;
+
+    char s_args[] = {"+proj=nell   +a=6400000    +lat_1=0.5 +lat_2=2"};
+
+    LP fwd_in[] = {
+        { 2, 1},
+        { 2,-1},
+        {-2, 1},
+        {-2,-1}
+    };
+
+    XY s_fwd_expect[] = {
+        { 223385.132504695706,  111698.23644718733},
+        { 223385.132504695706, -111698.23644718733},
+        {-223385.132504695706,  111698.23644718733},
+        {-223385.132504695706, -111698.23644718733},
+    };
+
+    XY inv_in[] = {
+        { 200, 100},
+        { 200,-100},
+        {-200, 100},
+        {-200,-100}
+    };
+
+    LP s_inv_expect[] = {
+        { 0.00179049310989310567,  0.000895246554910125161},
+        { 0.00179049310989310567, -0.000895246554910125161},
+        {-0.00179049310989310567,  0.000895246554910125161},
+        {-0.00179049310989310567, -0.000895246554910125161},
+    };
+
+    return pj_generic_selftest (0, s_args, tolerance_xy, tolerance_lp, 4, 4, fwd_in, 0, s_fwd_expect, inv_in, 0, s_inv_expect);
 }
-FREEUP; if (P) pj_dalloc(P); }
-ENTRY0(nell) P->es = 0; P->inv = s_inverse; P->fwd = s_forward; ENDENTRY(P)
+
+
+#endif