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(eck1, "Eckert I") "\n\tPCyl., Sph."; 31 #define FC .92131773192356127802 32 #define RP .31830988618379067154 33 FORWARD(s_forward); /* spheroid */ 34 (void) P; /* avoid warning */ 35 xy.x = FC * lp.lam * (1. - RP * fabs(lp.phi)); 36 xy.y = FC * lp.phi; 37 return (xy); 38 } 39 INVERSE(s_inverse); /* spheroid */ 40 (void) P; /* avoid warning */ 41 lp.phi = xy.y / FC; 42 lp.lam = xy.x / (FC * (1. - RP * fabs(lp.phi))); 43 return (lp); 44 } 45 FREEUP; if (P) free(P); } 46 ENTRY0(eck1) 47 P->es = 0.; P->inv = s_inverse; P->fwd = s_forward; 48 ENDENTRY(P) 49 /* 50 ** Log: proj_eck1.c 51 ** Revision 3.1 2006/01/11 01:38:18 gie 52 ** Initial 53 ** 54 */ 55