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Diffstat (limited to 'src/utils.cpp')
| -rw-r--r-- | src/utils.cpp | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/src/utils.cpp b/src/utils.cpp new file mode 100644 index 00000000..8587dc30 --- /dev/null +++ b/src/utils.cpp @@ -0,0 +1,181 @@ +/****************************************************************************** + * Project: PROJ.4 + * Purpose: Some utility functions we don't want to bother putting in + * their own source files. + * Author: Frank Warmerdam, warmerdam@pobox.com + * + ****************************************************************************** + * Copyright (c) 2001, Frank Warmerdam + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 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 PJ_LIB__ + +#include <stdio.h> +#include <string.h> + +#include "projects.h" + +/************************************************************************/ +/* pj_is_latlong() */ +/* */ +/* Returns TRUE if this coordinate system object is */ +/* geographic. */ +/************************************************************************/ + +int pj_is_latlong( PJ *pj ) + +{ + return pj == nullptr || pj->is_latlong; +} + +/************************************************************************/ +/* pj_is_geocent() */ +/* */ +/* Returns TRUE if this coordinate system object is geocentric. */ +/************************************************************************/ + +int pj_is_geocent( PJ *pj ) + +{ + return pj != nullptr && pj->is_geocent; +} + +/************************************************************************/ +/* pj_latlong_from_proj() */ +/* */ +/* Return a PJ* definition defining the lat/long coordinate */ +/* system on which a projection is based. If the coordinate */ +/* system passed in is latlong, a clone of the same will be */ +/* returned. */ +/************************************************************************/ + +PJ *pj_latlong_from_proj( PJ *pj_in ) + +{ + char defn[512]; + int got_datum = FALSE; + + pj_errno = 0; + strcpy( defn, "+proj=latlong" ); + + if( pj_param(pj_in->ctx, pj_in->params, "tdatum").i ) + { + got_datum = TRUE; + sprintf( defn+strlen(defn), " +datum=%s", + pj_param(pj_in->ctx, pj_in->params,"sdatum").s ); + } + else if( pj_param(pj_in->ctx, pj_in->params, "tellps").i ) + { + sprintf( defn+strlen(defn), " +ellps=%s", + pj_param(pj_in->ctx, pj_in->params,"sellps").s ); + } + else if( pj_param(pj_in->ctx,pj_in->params, "ta").i ) + { + sprintf( defn+strlen(defn), " +a=%s", + pj_param(pj_in->ctx,pj_in->params,"sa").s ); + + if( pj_param(pj_in->ctx,pj_in->params, "tb").i ) + sprintf( defn+strlen(defn), " +b=%s", + pj_param(pj_in->ctx,pj_in->params,"sb").s ); + else if( pj_param(pj_in->ctx,pj_in->params, "tes").i ) + sprintf( defn+strlen(defn), " +es=%s", + pj_param(pj_in->ctx,pj_in->params,"ses").s ); + else if( pj_param(pj_in->ctx,pj_in->params, "tf").i ) + sprintf( defn+strlen(defn), " +f=%s", + pj_param(pj_in->ctx,pj_in->params,"sf").s ); + else + { + char* ptr = defn+strlen(defn); + sprintf( ptr, " +es=%.16g", pj_in->es ); + /* TODO later: use C++ ostringstream with imbue(std::locale::classic()) */ + /* to be locale unaware */ + for(; *ptr; ptr++) + { + if( *ptr == ',' ) + *ptr = '.'; + } + } + } + else + { + pj_ctx_set_errno( pj_in->ctx, PJD_ERR_MAJOR_AXIS_NOT_GIVEN ); + + return nullptr; + } + + if( !got_datum ) + { + if( pj_param(pj_in->ctx,pj_in->params, "ttowgs84").i ) + sprintf( defn+strlen(defn), " +towgs84=%s", + pj_param(pj_in->ctx,pj_in->params,"stowgs84").s ); + + if( pj_param(pj_in->ctx,pj_in->params, "tnadgrids").i ) + sprintf( defn+strlen(defn), " +nadgrids=%s", + pj_param(pj_in->ctx,pj_in->params,"snadgrids").s ); + } + + /* copy over some other information related to ellipsoid */ + if( pj_param(pj_in->ctx,pj_in->params, "tR").i ) + sprintf( defn+strlen(defn), " +R=%s", + pj_param(pj_in->ctx,pj_in->params,"sR").s ); + + if( pj_param(pj_in->ctx,pj_in->params, "tR_A").i ) + sprintf( defn+strlen(defn), " +R_A" ); + + if( pj_param(pj_in->ctx,pj_in->params, "tR_V").i ) + sprintf( defn+strlen(defn), " +R_V" ); + + if( pj_param(pj_in->ctx,pj_in->params, "tR_a").i ) + sprintf( defn+strlen(defn), " +R_a" ); + + if( pj_param(pj_in->ctx,pj_in->params, "tR_lat_a").i ) + sprintf( defn+strlen(defn), " +R_lat_a=%s", + pj_param(pj_in->ctx,pj_in->params,"sR_lat_a").s ); + + if( pj_param(pj_in->ctx,pj_in->params, "tR_lat_g").i ) + sprintf( defn+strlen(defn), " +R_lat_g=%s", + pj_param(pj_in->ctx,pj_in->params,"sR_lat_g").s ); + + /* copy over prime meridian */ + if( pj_param(pj_in->ctx,pj_in->params, "tpm").i ) + sprintf( defn+strlen(defn), " +pm=%s", + pj_param(pj_in->ctx,pj_in->params,"spm").s ); + + return pj_init_plus_ctx( pj_in->ctx, defn ); +} + +/************************************************************************/ +/* pj_get_spheroid_defn() */ +/* */ +/* Fetch the internal definition of the spheroid. Note that */ +/* you can compute "b" from eccentricity_squared as: */ +/* */ +/* b = a * sqrt(1 - es) */ +/************************************************************************/ + +void pj_get_spheroid_defn(projPJ defn, double *major_axis, double *eccentricity_squared) +{ + if ( major_axis ) + *major_axis = defn->a; + + if ( eccentricity_squared ) + *eccentricity_squared = defn->es; +} |