New

git-svn-id: http://svn.osgeo.org/metacrs/proj/trunk@776 4e78687f-474d-0410-85f9-8d5e500ac6b2

1 files changed, 148 insertions, 0 deletions

diff --git a/src/PJ_tmerc.c b/src/PJ_tmerc.c
new file mode 100644
index 00000000..bac2db3e
--- /dev/null
+++ b/src/PJ_tmerc.c
@@ -0,0 +1,148 @@
+#ifndef lint
+static const char SCCSID[]="@(#)PJ_tmerc.c	4.2	94/06/02	GIE	REL";
+#endif
+#define PROJ_PARMS__ \
+	double	esp; \
+	double	ml0; \
+	double	*en;
+#define PJ_LIB__
+#include	<projects.h>
+PROJ_HEAD(tmerc, "Transverse Mercator") "\n\tCyl, Sph&Ell";
+PROJ_HEAD(utm, "Universal Transverse Mercator (UTM)")
+	"\n\tCyl, Sph\n\tzone= south";
+#define EPS10	1.e-10
+#define aks0	P->esp
+#define aks5	P->ml0
+#define FC1 1.
+#define FC2 .5
+#define FC3 .16666666666666666666
+#define FC4 .08333333333333333333
+#define FC5 .05
+#define FC6 .03333333333333333333
+#define FC7 .02380952380952380952
+#define FC8 .01785714285714285714
+FORWARD(e_forward); /* ellipse */
+	double al, als, n, cosphi, sinphi, t;
+
+	sinphi = sin(lp.phi); cosphi = cos(lp.phi);
+	t = fabs(cosphi) > 1e-10 ? sinphi/cosphi : 0.;
+	t *= t;
+	al = cosphi * lp.lam;
+	als = al * al;
+	al /= sqrt(1. - P->es * sinphi * sinphi);
+	n = P->esp * cosphi * cosphi;
+	xy.x = P->k0 * al * (FC1 +
+		FC3 * als * (1. - t + n +
+		FC5 * als * (5. + t * (t - 18.) + n * (14. - 58. * t)
+		+ FC7 * als * (61. + t * ( t * (179. - t) - 479. ) )
+		)));
+	xy.y = P->k0 * (pj_mlfn(lp.phi, sinphi, cosphi, P->en) - P->ml0 +
+		sinphi * al * lp.lam * FC2 * ( 1. +
+		FC4 * als * (5. - t + n * (9. + 4. * n) +
+		FC6 * als * (61. + t * (t - 58.) + n * (270. - 330 * t)
+		+ FC8 * als * (1385. + t * ( t * (543. - t) - 3111.) )
+		))));
+	return (xy);
+}
+FORWARD(s_forward); /* sphere */
+	double b, cosphi;
+
+	b = (cosphi = cos(lp.phi)) * sin(lp.lam);
+	if (fabs(fabs(b) - 1.) <= EPS10) F_ERROR;
+	xy.x = aks5 * log((1. + b) / (1. - b));
+	if ((b = fabs( xy.y = cosphi * cos(lp.lam) / sqrt(1. - b * b) )) >= 1.) {
+		if ((b - 1.) > EPS10) F_ERROR
+		else xy.y = 0.;
+	} else
+		xy.y = acos(xy.y);
+	if (lp.phi < 0.) xy.y = -xy.y;
+	xy.y = aks0 * (xy.y - P->phi0);
+	return (xy);
+}
+INVERSE(e_inverse); /* ellipsoid */
+	double n, con, cosphi, d, ds, sinphi, t;
+
+	lp.phi = pj_inv_mlfn(P->ml0 + xy.y / P->k0, P->es, P->en);
+	if (fabs(lp.phi) >= HALFPI) {
+		lp.phi = xy.y < 0. ? -HALFPI : HALFPI;
+		lp.lam = 0.;
+	} else {
+		sinphi = sin(lp.phi);
+		cosphi = cos(lp.phi);
+		t = fabs(cosphi) > 1e-10 ? sinphi/cosphi : 0.;
+		n = P->esp * cosphi * cosphi;
+		d = xy.x * sqrt(con = 1. - P->es * sinphi * sinphi) / P->k0;
+		con *= t;
+		t *= t;
+		ds = d * d;
+		lp.phi -= (con * ds / (1.-P->es)) * FC2 * (1. -
+			ds * FC4 * (5. + t * (3. - 9. *  n) + n * (1. - 4 * n) -
+			ds * FC6 * (61. + t * (90. - 252. * n +
+				45. * t) + 46. * n
+		   - ds * FC8 * (1385. + t * (3633. + t * (4095. + 1574. * t)) )
+			)));
+		lp.lam = d*(FC1 -
+			ds*FC3*( 1. + 2.*t + n -
+			ds*FC5*(5. + t*(28. + 24.*t + 8.*n) + 6.*n
+		   - ds * FC7 * (61. + t * (662. + t * (1320. + 720. * t)) )
+		))) / cosphi;
+	}
+	return (lp);
+}
+INVERSE(s_inverse); /* sphere */
+	double h, g;
+
+	h = exp(xy.x / aks0);
+	g = .5 * (h - 1. / h);
+	h = cos(P->phi0 + xy.y / aks0);
+	lp.phi = asin(sqrt((1. - h * h) / (1. + g * g)));
+	if (xy.y < 0.) lp.phi = -lp.phi;
+	lp.lam = (g || h) ? atan2(g, h) : 0.;
+	return (lp);
+}
+FREEUP;
+	if (P) {
+		if (P->en)
+			pj_dalloc(P->en);
+		pj_dalloc(P);
+	}
+}
+	static PJ *
+setup(PJ *P) { /* general initialization */
+	if (P->es) {
+		if (!(P->en = pj_enfn(P->es)))
+			E_ERROR_0;
+		P->ml0 = pj_mlfn(P->phi0, sin(P->phi0), cos(P->phi0), P->en);
+		P->esp = P->es / (1. - P->es);
+		P->inv = e_inverse;
+		P->fwd = e_forward;
+	} else {
+		aks0 = P->k0;
+		aks5 = .5 * aks0;
+		P->inv = s_inverse;
+		P->fwd = s_forward;
+	}
+	return P;
+}
+ENTRY1(tmerc, en)
+ENDENTRY(setup(P))
+ENTRY1(utm, en)
+	int zone;
+
+	if (!P->es) E_ERROR(-34);
+	P->y0 = pj_param(P->params, "bsouth").i ? 10000000. : 0.;
+	P->x0 = 500000.;
+	if (pj_param(P->params, "tzone").i) /* zone input ? */
+		if ((zone = pj_param(P->params, "izone").i) > 0 && zone <= 60)
+			--zone;
+		else
+			E_ERROR(-35)
+	else /* nearest central meridian input */
+		if ((zone = floor((adjlon(P->lam0) + PI) * 30. / PI)) < 0)
+			zone = 0;
+		else if (zone >= 60)
+			zone = 59;
+	P->lam0 = (zone + .5) * PI / 30. - PI;
+	P->k0 = 0.9996;
+	P->phi0 = 0.;
+ENDENTRY(setup(P))