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Diffstat (limited to 'src/3rdparty/proj/pj_inv.c')
-rw-r--r--src/3rdparty/proj/pj_inv.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/src/3rdparty/proj/pj_inv.c b/src/3rdparty/proj/pj_inv.c
new file mode 100644
index 00000000..ee2b44f8
--- /dev/null
+++ b/src/3rdparty/proj/pj_inv.c
@@ -0,0 +1,29 @@
+/* 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_errno = -15;
+ }
+ errno = pj_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;
+ lp = (*P->inv)(xy, P); /* inverse project */
+ if (pj_errno || (pj_errno = 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)-HALFPI) > EPS)
+ lp.phi = atan(P->one_es * tan(lp.phi));
+ }
+ return lp;
+}