Application: gvSIG desktop

#ifndef lint

static const char SCCSID[]="@(#)PJ_bacon.c        4.1        94/02/15        GIE        REL";

#endif

# define HLFPI2        2.46740110027233965467

# define EPS        1e-10

#define PROJ_PARMS__ \

        int bacn; \

        int ortl;

#define PJ_LIB__

#include        <projects.h>

PROJ_HEAD(apian, "Apian Globular I") "\n\tMisc Sph, no inv.";

PROJ_HEAD(ortel, "Ortelius Oval") "\n\tMisc Sph, no inv.";

PROJ_HEAD(bacon, "Bacon Globular") "\n\tMisc Sph, no inv.";

FORWARD(s_forward); /* spheroid */

        double ax, f;

        xy.y = P->bacn ? HALFPI * sin(lp.phi) : lp.phi;

        if ((ax = fabs(lp.lam)) >= EPS) {

                if (P->ortl && ax >= HALFPI)

                        xy.x = sqrt(HLFPI2 - lp.phi * lp.phi + EPS) + ax - HALFPI;

                else {

                        f = 0.5 * (HLFPI2 / ax + ax);

                        xy.x = ax - f + sqrt(f * f - xy.y * xy.y);

                }

                if (lp.lam < 0.) xy.x = - xy.x;

        } else

                xy.x = 0.;

        return (xy);

}

FREEUP; if (P) pj_dalloc(P); }

ENTRY0(bacon)

        P->bacn = 1;

        P->ortl = 0;

        P->es = 0.; P->fwd = s_forward;

ENDENTRY(P)

ENTRY0(apian)

        P->bacn = P->ortl = 0;

        P->es = 0.; P->fwd = s_forward;

ENDENTRY(P)

ENTRY0(ortel)

        P->bacn = 0;

        P->ortl = 1;

        P->es = 0.; P->fwd = s_forward;

ENDENTRY(P)