New

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

1 files changed, 112 insertions, 0 deletions

diff --git a/src/PJ_labrd.c b/src/PJ_labrd.c
new file mode 100644
index 00000000..01b0406f
--- /dev/null
+++ b/src/PJ_labrd.c
@@ -0,0 +1,112 @@
+#ifndef lint
+static const char SCCSID[]="@(#)PJ_labrd.c	4.1	94/02/15	GIE	REL";
+#endif
+#define PROJ_PARMS__ \
+	double	Az, kRg, p0s, A, C, Ca, Cb, Cc, Cd; \
+	int		rot;
+#define PJ_LIB__
+#include	<projects.h>
+PROJ_HEAD(labrd, "Laborde") "\n\tCyl, Sph\n\tSpecial for Madagascar";
+#define EPS	1.e-10
+FORWARD(e_forward);
+	double V1, V2, ps, sinps, cosps, sinps2, cosps2, I1, I2, I3, I4, I5, I6,
+		x2, y2, t;
+
+	V1 = P->A * log( tan(FORTPI + .5 * lp.phi) );
+	t = P->e * sin(lp.phi);
+	V2 = .5 * P->e * P->A * log ((1. + t)/(1. - t));
+	ps = 2. * (atan(exp(V1 - V2 + P->C)) - FORTPI);
+	I1 = ps - P->p0s;
+	cosps = cos(ps);	cosps2 = cosps * cosps;
+	sinps = sin(ps);	sinps2 = sinps * sinps;
+	I4 = P->A * cosps;
+	I2 = .5 * P->A * I4 * sinps;
+	I3 = I2 * P->A * P->A * (5. * cosps2 - sinps2) / 12.;
+	I6 = I4 * P->A * P->A;
+	I5 = I6 * (cosps2 - sinps2) / 6.;
+	I6 *= P->A * P->A *
+		(5. * cosps2 * cosps2 + sinps2 * (sinps2 - 18. * cosps2)) / 120.;
+	t = lp.lam * lp.lam;
+	xy.x = P->kRg * lp.lam * (I4 + t * (I5 + t * I6));
+	xy.y = P->kRg * (I1 + t * (I2 + t * I3));
+	x2 = xy.x * xy.x;
+	y2 = xy.y * xy.y;
+	V1 = 3. * xy.x * y2 - xy.x * x2;
+	V2 = xy.y * y2 - 3. * x2 * xy.y;
+	xy.x += P->Ca * V1 + P->Cb * V2;
+	xy.y += P->Ca * V2 - P->Cb * V1;
+	return (xy);
+}
+INVERSE(e_inverse); /* ellipsoid & spheroid */
+	double x2, y2, V1, V2, V3, V4, t, t2, ps, pe, tpe, s,
+		I7, I8, I9, I10, I11, d, Re;
+	int i;
+
+	x2 = xy.x * xy.x;
+	y2 = xy.y * xy.y;
+	V1 = 3. * xy.x * y2 - xy.x * x2;
+	V2 = xy.y * y2 - 3. * x2 * xy.y;
+	V3 = xy.x * (5. * y2 * y2 + x2 * (-10. * y2 + x2 ));
+	V4 = xy.y * (5. * x2 * x2 + y2 * (-10. * x2 + y2 ));
+	xy.x += - P->Ca * V1 - P->Cb * V2 + P->Cc * V3 + P->Cd * V4;
+	xy.y +=   P->Cb * V1 - P->Ca * V2 - P->Cd * V3 + P->Cc * V4;
+	ps = P->p0s + xy.y / P->kRg;
+	pe = ps + P->phi0 - P->p0s;
+	for ( i = 20; i; --i) {
+		V1 = P->A * log(tan(FORTPI + .5 * pe));
+		tpe = P->e * sin(pe);
+		V2 = .5 * P->e * P->A * log((1. + tpe)/(1. - tpe));
+		t = ps - 2. * (atan(exp(V1 - V2 + P->C)) - FORTPI);
+		pe += t;
+		if (fabs(t) < EPS)
+			break;
+	}
+/*
+	if (!i) {
+	} else {
+	}
+*/
+	t = P->e * sin(pe);
+	t = 1. - t * t;
+	Re = P->one_es / ( t * sqrt(t) );
+	t = tan(ps);
+	t2 = t * t;
+	s = P->kRg * P->kRg;
+	d = Re * P->k0 * P->kRg;
+	I7 = t / (2. * d);
+	I8 = t * (5. + 3. * t2) / (24. * d * s);
+	d = cos(ps) * P->kRg * P->A;
+	I9 = 1. / d;
+	d *= s;
+	I10 = (1. + 2. * t2) / (6. * d);
+	I11 = (5. + t2 * (28. + 24. * t2)) / (120. * d * s);
+	x2 = xy.x * xy.x;
+	lp.phi = pe + x2 * (-I7 + I8 * x2);
+	lp.lam = xy.x * (I9 + x2 * (-I10 + x2 * I11));
+	return (lp);
+}
+FREEUP; if (P) pj_dalloc(P); }
+ENTRY0(labrd)
+	double Az, sinp, R, N, t;
+
+	P->rot	= pj_param(P->params, "bno_rot").i == 0;
+	Az = pj_param(P->params, "razi").f;
+	sinp = sin(P->phi0);
+	t = 1. - P->es * sinp * sinp;
+	N = 1. / sqrt(t);
+	R = P->one_es * N / t;
+	P->kRg = P->k0 * sqrt( N * R );
+	P->p0s = atan( sqrt(R / N) * tan(P->phi0) );
+	P->A = sinp / sin(P->p0s);
+	t = P->e * sinp;
+	P->C = .5 * P->e * P->A * log((1. + t)/(1. - t)) +
+		- P->A * log( tan(FORTPI + .5 * P->phi0))
+		+ log( tan(FORTPI + .5 * P->p0s));
+	t = Az + Az;
+	P->Ca = (1. - cos(t)) * ( P->Cb = 1. / (12. * P->kRg * P->kRg) );
+	P->Cb *= sin(t);
+	P->Cc = 3. * (P->Ca * P->Ca - P->Cb * P->Cb);
+	P->Cd = 6. * P->Ca * P->Cb;
+	P->inv = e_inverse;
+	P->fwd = e_forward;
+ENDENTRY(P)