该项目的最新进展包括地图共享模块，android同事集团开始，使用百度地图sdk，我开始回，运用iOS SDK的mapkit做，之后，问题是，用纬度和经度坐标iOS端和Android端出现了比較大偏差。查了下资料苹果地图在大陆的数据源是高德的，查了下高德採用GCJ-02, 百度map sdk 採用的是BD-09。仅仅好写了个类在发送和接收时做好转换，稍微蛋疼。Github上有人写了一个现成的转换类，能够參考參考传送门 。其主要代码见下：
头文件：
#import <Foundation/Foundation.h>#import <CoreLocation/CoreLocation.h>@interface JZLocationConverter : NSObject/***@brief世界标准地理坐标(WGS-84) 转换成 中国国測局地理坐标（GCJ-02）<火星坐标>** ####仅仅在中国大陆的范围的坐标有效，以外直接返回世界标准坐标**@param location 世界标准地理坐标(WGS-84)**@return中国国測局地理坐标（GCJ-02）<火星坐标>*/+ (CLLocationCoordinate2D)wgs84ToGcj02:(CLLocationCoordinate2D)location;/***@brief中国国測局地理坐标（GCJ-02） 转换成 世界标准地理坐标（WGS-84）** ####此接口有1－2米左右的误差，须要精确定位情景慎用**@param location 中国国測局地理坐标（GCJ-02）**@return世界标准地理坐标（WGS-84）*/+ (CLLocationCoordinate2D)gcj02ToWgs84:(CLLocationCoordinate2D)location;/***@brief世界标准地理坐标(WGS-84) 转换成 百度地理坐标（BD-09)**@param location 世界标准地理坐标(WGS-84)**@return百度地理坐标（BD-09)*/+ (CLLocationCoordinate2D)wgs84ToBd09:(CLLocationCoordinate2D)location;/***@brief中国国測局地理坐标（GCJ-02）<火星坐标> 转换成 百度地理坐标（BD-09)**@param location 中国国測局地理坐标（GCJ-02）<火星坐标>**@return百度地理坐标（BD-09)*/+ (CLLocationCoordinate2D)gcj02ToBd09:(CLLocationCoordinate2D)location;/***@brief百度地理坐标（BD-09) 转换成 中国国測局地理坐标（GCJ-02）<火星坐标>**@param location 百度地理坐标（BD-09)**@return中国国測局地理坐标（GCJ-02）<火星坐标>*/+ (CLLocationCoordinate2D)bd09ToGcj02:(CLLocationCoordinate2D)location;/***@brief百度地理坐标（BD-09) 转换成 世界标准地理坐标（WGS-84）** ####此接口有1－2米左右的误差，须要精确定位情景慎用**@param location 百度地理坐标（BD-09)**@return世界标准地理坐标（WGS-84）*/+ (CLLocationCoordinate2D)bd09ToWgs84:(CLLocationCoordinate2D)location;@end
实现文件
#import "JZLocationConverter.h"#import <CoreLocation/CoreLocation.h>#define LAT_OFFSET_0(x,y) -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * sqrt(fabs(x))#define LAT_OFFSET_1 (20.0 * sin(6.0 * x * M_PI) + 20.0 * sin(2.0 * x * M_PI)) * 2.0 / 3.0#define LAT_OFFSET_2 (20.0 * sin(y * M_PI) + 40.0 * sin(y / 3.0 * M_PI)) * 2.0 / 3.0#define LAT_OFFSET_3 (160.0 * sin(y / 12.0 * M_PI) + 320 * sin(y * M_PI / 30.0)) * 2.0 / 3.0#define LON_OFFSET_0(x,y) 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * sqrt(fabs(x))#define LON_OFFSET_1 (20.0 * sin(6.0 * x * M_PI) + 20.0 * sin(2.0 * x * M_PI)) * 2.0 / 3.0#define LON_OFFSET_2 (20.0 * sin(x * M_PI) + 40.0 * sin(x / 3.0 * M_PI)) * 2.0 / 3.0#define LON_OFFSET_3 (150.0 * sin(x / 12.0 * M_PI) + 300.0 * sin(x / 30.0 * M_PI)) * 2.0 / 3.0#define RANGE_LON_MAX 137.8347#define RANGE_LON_MIN 72.004#define RANGE_LAT_MAX 55.8271#define RANGE_LAT_MIN 0.8293// jzA = 6378245.0, 1/f = 298.3// b = a * (1 - f)// ee = (a^2 - b^2) / a^2;#define jzA 6378245.0#define jzEE 0.00669342162296594323@implementation JZLocationConverter+ (double)transformLat:(double)x bdLon:(double)y{double ret = LAT_OFFSET_0(x, y);ret += LAT_OFFSET_1;ret += LAT_OFFSET_2;ret += LAT_OFFSET_3;return ret;}+ (double)transformLon:(double)x bdLon:(double)y{double ret = LON_OFFSET_0(x, y);ret += LON_OFFSET_1;ret += LON_OFFSET_2;ret += LON_OFFSET_3;return ret;}+ (BOOL)outOfChina:(double)lat bdLon:(double)lon{if (lon < RANGE_LON_MIN || lon > RANGE_LON_MAX)return true;if (lat < RANGE_LAT_MIN || lat > RANGE_LAT_MAX)return true;return false;}+ (CLLocationCoordinate2D)gcj02Encrypt:(double)ggLat bdLon:(double)ggLon{CLLocationCoordinate2D resPoint;double mgLat;double mgLon;if ([self outOfChina:ggLat bdLon:ggLon]) {resPoint.latitude = ggLat;resPoint.longitude = ggLon;return resPoint;}double dLat = [self transformLat:(ggLon - 105.0)bdLon:(ggLat - 35.0)];double dLon = [self transformLon:(ggLon - 105.0) bdLon:(ggLat - 35.0)];double radLat = ggLat / 180.0 * M_PI;double magic = sin(radLat);magic = 1 - jzEE * magic * magic;double sqrtMagic = sqrt(magic);dLat = (dLat * 180.0) / ((jzA * (1 - jzEE)) / (magic * sqrtMagic) * M_PI);dLon = (dLon * 180.0) / (jzA / sqrtMagic * cos(radLat) * M_PI);mgLat = ggLat + dLat;mgLon = ggLon + dLon;resPoint.latitude = mgLat;resPoint.longitude = mgLon;return resPoint;}+ (CLLocationCoordinate2D)gcj02Decrypt:(double)gjLat gjLon:(double)gjLon {CLLocationCoordinate2D gPt = [self gcj02Encrypt:gjLat bdLon:gjLon];double dLon = gPt.longitude - gjLon;double dLat = gPt.latitude - gjLat;CLLocationCoordinate2D pt;pt.latitude = gjLat - dLat;pt.longitude = gjLon - dLon;return pt;}+ (CLLocationCoordinate2D)bd09Decrypt:(double)bdLat bdLon:(double)bdLon{CLLocationCoordinate2D gcjPt;double x = bdLon - 0.0065, y = bdLat - 0.006;double z = sqrt(x * x + y * y) - 0.00002 * sin(y * M_PI);double theta = atan2(y, x) - 0.000003 * cos(x * M_PI);gcjPt.longitude = z * cos(theta);gcjPt.latitude = z * sin(theta);return gcjPt;}+(CLLocationCoordinate2D)bd09Encrypt:(double)ggLat bdLon:(double)ggLon{CLLocationCoordinate2D bdPt;double x = ggLon, y = ggLat;double z = sqrt(x * x + y * y) + 0.00002 * sin(y * M_PI);double theta = atan2(y, x) + 0.000003 * cos(x * M_PI);bdPt.longitude = z * cos(theta) + 0.0065;bdPt.latitude = z * sin(theta) + 0.006;return bdPt;}+ (CLLocationCoordinate2D)wgs84ToGcj02:(CLLocationCoordinate2D)location{return [self gcj02Encrypt:location.latitude bdLon:location.longitude];}+ (CLLocationCoordinate2D)gcj02ToWgs84:(CLLocationCoordinate2D)location{return [self gcj02Decrypt:location.latitude gjLon:location.longitude];}+ (CLLocationCoordinate2D)wgs84ToBd09:(CLLocationCoordinate2D)location{CLLocationCoordinate2D gcj02Pt = [self gcj02Encrypt:location.latitudebdLon:location.longitude];return [self bd09Encrypt:gcj02Pt.latitude bdLon:gcj02Pt.longitude] ;}+ (CLLocationCoordinate2D)gcj02ToBd09:(CLLocationCoordinate2D)location{return [self bd09Encrypt:location.latitude bdLon:location.longitude];}+ (CLLocationCoordinate2D)bd09ToGcj02:(CLLocationCoordinate2D)location{return [self bd09Decrypt:location.latitude bdLon:location.longitude];}+ (CLLocationCoordinate2D)bd09ToWgs84:(CLLocationCoordinate2D)location{CLLocationCoordinate2D gcj02 = [self bd09ToGcj02:location];return [self gcj02Decrypt:gcj02.latitude gjLon:gcj02.longitude];}@end
測试用例：
CLLocationCoordinate2D gcj02 = CLLocationCoordinate2DMake(114.21892734521,29.575429778924);CLLocationCoordinate2D bd09 = [JZLocationConverter gcj02ToBd09:gcj02];NSLog(@"%f,%f", bd09.latitude, bd09.longitude); // /map/index.php?title=webapi/guide/changeposition// JZLocationConverter 測试数据: 114.21892734521,29.575429778924 ; 转化结果: 114.224960,29.581853// 百度api 測试数据: 114.21892734521,29.575429778924 ; 百度api转换结果: 114.22539195429,29.581585367458
整体来说，存在一点偏差，但跟处理前的效果比一下。相对能够接受了些。
參考：
/jiajiayouba/article/details/25140967
/map/index.php?
title=webapi/guide/changeposition
/winnyrain/article/details/22233559
/article/17
/coolypf/article/details/8569813
/socketref/archive//06/29/149713.html
版权声明：本文博主原创文章，博客，未经同意。
