1 /* 2 ** libproj -- library of cartographic projections 3 ** 4 ** Copyright (c) 2003, 2006 Gerald I. Evenden 5 */ 6 static const char 7 LIBPROJ_ID[] = "Id"; 8 /* 9 ** Permission is hereby granted, free of charge, to any person obtaining 10 ** a copy of this software and associated documentation files (the 11 ** "Software"), to deal in the Software without restriction, including 12 ** without limitation the rights to use, copy, modify, merge, publish, 13 ** distribute, sublicense, and/or sell copies of the Software, and to 14 ** permit persons to whom the Software is furnished to do so, subject to 15 ** the following conditions: 16 ** 17 ** The above copyright notice and this permission notice shall be 18 ** included in all copies or substantial portions of the Software. 19 ** 20 ** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 21 ** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 22 ** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 23 ** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 24 ** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 25 ** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 26 ** SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 27 */ 28 #define PROJ_LIB__ 29 # include <lib_proj.h> 30 PROJ_HEAD(fahey, "Fahey") "\n\tPcyl, Sph."; 31 #define TOL 1e-6 32 FORWARD(s_forward); /* spheroid */ 33 (void) P; /* avoid warning */ 34 xy.y = 1.819152 * ( xy.x = tan(0.5 * lp.phi) ); 35 xy.x = 0.819152 * lp.lam * proj_sqrt(1 - xy.x * xy.x); 36 return (xy); 37 } 38 INVERSE(s_inverse); /* spheroid */ 39 (void) P; /* avoid warning */ 40 lp.phi = 2. * atan(xy.y /= 1.819152); 41 lp.lam = fabs(xy.y = 1. - xy.y * xy.y) < TOL ? 0. : 42 xy.x / (0.819152 * sqrt(xy.y)); 43 return (lp); 44 } 45 FREEUP; if (P) free(P); } 46 ENTRY0(fahey) P->es = 0.; P->inv = s_inverse; P->fwd = s_forward; ENDENTRY(P) 47 /* 48 ** Log: proj_fahey.c 49 ** Revision 3.1 2006/01/11 01:38:18 gie 50 ** Initial 51 ** 52 */ 53