** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. ** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY ** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, ** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE ** SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #define PROJ_PARMS__ \ double qp; \ double *apa; #define PROJ_LIB__ # include <lib_proj.h> PROJ_HEAD(cea, "Equal Area Cylindrical") "\n\tCyl, Sph&Ell\n\tlat_ts=(0)"; # define EPS 1e-10 FORWARD(e_forward); /* ellipsoid */ xy.x = P->k0 * lp.lam; xy.y = .5 * proj_qsfn(lp.phi, P->apa) / P->k0; return (xy); } FORWARD(s_forward); /* spheroid */ xy.x = P->k0 * lp.lam; xy.y = sin(lp.phi) / P->k0; return (xy); } INVERSE(e_inverse); /* ellipsoid */ lp.phi = proj_auth_inv(asin( 2. * xy.y * P->k0 / P->qp), P->apa); lp.lam = xy.x / P->k0; return (lp); } INVERSE(s_inverse); /* spheroid */ double t;
#define sinph0 P->sinb1
#define cosph0 P->cosb1
#define EPS10 1.e-10
#define NITER 20
#define CONV 1.e-10
#define N_POLE 0
#define S_POLE 1
#define EQUIT 2
#define OBLIQ 3
FORWARD(e_forward); /* ellipsoid */
double coslam, sinlam, sinphi, q, sinb=0., cosb=0., b=0.;
coslam = cos(lp.lam);
sinlam = sin(lp.lam);
sinphi = sin(lp.phi);
q = proj_qsfn(lp.phi, P->apa);
if (P->mode == OBLIQ || P->mode == EQUIT) {
sinb = q / P->qp;
cosb = sqrt(1. - sinb * sinb);
}
switch (P->mode) {
case OBLIQ:
b = 1. + P->sinb1 * sinb + P->cosb1 * cosb * coslam;
break;
case EQUIT:
b = 1. + cosb * coslam;
break;
case N_POLE:
b = HALFPI + lp.phi;
q = P->qp - q;
break;
