recorder/geohash.h
2015-08-14 18:40:35 +02:00

77 lines
2.6 KiB
C

/*
* geohash.h
* libgeohash
*
* Created by Derek Smith on 10/6/09.
* Copyright (c) 2010, SimpleGeo
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this list
* of conditions and the following disclaimer. Redistributions in binary form must
* reproduce the above copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided with the distribution.
* Neither the name of the SimpleGeo nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
// Metric in meters
typedef struct GeoBoxDimensionStruct {
double height;
double width;
} GeoBoxDimension;
typedef struct GeoCoordStruct {
double latitude;
double longitude;
double north;
double east;
double south;
double west;
GeoBoxDimension dimension;
} GeoCoord;
/*
* Creates a the hash at the specified precision. If precision is set to 0.
* or less than it defaults to 12.
*/
extern char* geohash_encode(double lat, double lng, int precision);
/*
* Returns the latitude and longitude used to create the hash along with
* the bounding box for the encoded coordinate.
*/
extern GeoCoord geohash_decode(char* hash);
/*
* Return an array of geohashes that represent the neighbors of the passed
* in value. The neighbors are indexed as followed:
*
* N, NE, E, SE, S, SW, W, NW
* 0, 1, 2, 3, 4, 5, 6, 7
*/
extern char** geohash_neighbors(char* hash);
/*
* Returns the width and height of a precision value.
*/
extern GeoBoxDimension geohash_dimensions_for_precision(int precision);