blob: 9a3417697c039d9825d918a5bc9cac9da34c08d4 (
plain)
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
|
/* general inverse projection */
#define PJ_LIB__
#include <projects.h>
#include <errno.h>
# define EPS 1.0e-12
LP /* inverse projection entry */
pj_inv(XY xy, PJ *P) {
LP lp;
/* can't do as much preliminary checking as with forward */
if (xy.x == HUGE_VAL || xy.y == HUGE_VAL) {
lp.lam = lp.phi = HUGE_VAL;
pj_ctx_set_errno( P->ctx, -15);
return lp;
}
errno = pj_errno = 0;
P->ctx->last_errno = 0;
xy.x = (xy.x * P->to_meter - P->x0) * P->ra; /* descale and de-offset */
xy.y = (xy.y * P->to_meter - P->y0) * P->ra;
/* Check for NULL pointer */
if (P->inv != NULL)
{
lp = (*P->inv)(xy, P); /* inverse project */
if (P->ctx->last_errno )
lp.lam = lp.phi = HUGE_VAL;
else {
lp.lam += P->lam0; /* reduce from del lp.lam */
if (!P->over)
lp.lam = adjlon(lp.lam); /* adjust longitude to CM */
if (P->geoc && fabs(fabs(lp.phi)-M_HALFPI) > EPS)
lp.phi = atan(P->one_es * tan(lp.phi));
}
}
else
{
lp.lam = lp.phi = HUGE_VAL;
}
return lp;
}
|
