1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81
|
#define PJ_LIB__
#include <projects.h>
PROJ_HEAD(urm5, "Urmaev V") "\n\tPCyl., Sph., no inv.\n\tn= q= alpha=";
struct pj_opaque {
double m, rmn, q3, n;
};
static XY s_forward (LP lp, PJ *P) { /* Spheroidal, forward */
XY xy = {0.0, 0.0};
struct pj_opaque *Q = P->opaque;
double t;
t = lp.phi = aasin (P->ctx, Q->n * sin (lp.phi));
xy.x = Q->m * lp.lam * cos (lp.phi);
t *= t;
xy.y = lp.phi * (1. + t * Q->q3) * Q->rmn;
return xy;
}
static void *freeup_new (PJ *P) { /* Destructor */
return pj_dealloc(P);
}
static void freeup (PJ *P) {
freeup_new (P);
return;
}
PJ *PROJECTION(urm5) {
double alpha, t;
struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
if (0==Q)
return freeup_new (P);
P->opaque = Q;
Q->n = pj_param(P->ctx, P->params, "dn").f;
Q->q3 = pj_param(P->ctx, P->params, "dq").f / 3.;
alpha = pj_param(P->ctx, P->params, "ralpha").f;
t = Q->n * sin (alpha);
Q->m = cos (alpha) / sqrt (1. - t * t);
Q->rmn = 1. / (Q->m * Q->n);
P->es = 0.;
P->inv = 0;
P->fwd = s_forward;
return P;
}
#ifndef PJ_SELFTEST
int pj_urm5_selftest (void) {return 0;}
#else
int pj_urm5_selftest (void) {
double tolerance_lp = 1e-10;
double tolerance_xy = 1e-7;
char s_args[] = {"+proj=urm5 +a=6400000 +lat_1=0.5 +lat_2=2"};
LP fwd_in[] = {
{ 2, 1},
{ 2,-1},
{-2, 1},
{-2,-1}
};
XY s_fwd_expect[] = {
{ 223393.6384339639, 111696.81878511712},
{ 223393.6384339639, -111696.81878511712},
{-223393.6384339639, 111696.81878511712},
{-223393.6384339639, -111696.81878511712},
};
return pj_generic_selftest (0, s_args, tolerance_xy, tolerance_lp, 4, 4, fwd_in, 0, s_fwd_expect, 0, 0, 0);
}
#endif
|