WGS84到Google地图位置和返回的Java代码
问题描述:
搜索将WGS84坐标系中的点转换为Google地图中的地图位置(像素位置)的一些示例代码,同样支持缩放级别。WGS84到Google地图位置和返回的Java代码
如果代码评论得很好,那么它也可以是其他语言。
您还可以点我一个开源Java项目:)
发现的一些资源:
OpenLayer实施。
JOSM项目
优秀Java Map Projection Library从JH LABS。这是一个纯java PROJ.4端口。从WGS84投影到米。从那里转换米到像素是非常简单的。
答
下面是JavaScript中的功能......作为从的OpenLayers
提取function toMercator (lon, lat) {
var x = lon * 20037508.34/180;
var y = Math.log(Math.tan((90 + lat) * Math.PI/360))/(Math.PI/180);
y = y * 20037508.34/180;
return [x, y];
}
function inverseMercator (x, y) {
var lon = (x/20037508.34) * 180;
var lat = (y/20037508.34) * 180;
lat = 180/Math.PI * (2 * Math.atan(Math.exp(lat * Math.PI/180)) - Math.PI/2);
return [lon, lat];
}
相当简单转换成Java
答
我移植这PHP - 这里的代码,如果有人需要它:
要麦卡托:
$lon = ($lon * 20037508.34)/180;
$lat = log(tan((90 + $lat) * M_PI/360))/(M_PI/180);
$lat = $lat * 20037508.34/180;
从墨卡托:
$lon = ($lon/20037508.34) * 180;
$lat = ($lat/20037508.34) * 180;
$lat = 180/M_PI * (2 * atan(exp($lat * M_PI/180)) - M_PI/2);
答
/*
* Utility functions to transform between wgs84 and google projection coordinates
* Derived from openmap http://openmap.bbn.com/
*/
public class MercatorTransform {
public final static double NORTH_POLE = 90.0;
public final static double SOUTH_POLE = -NORTH_POLE;
public final static double DATELINE = 180.0;
public final static double LON_RANGE = 360.0;
final public static transient double wgs84_earthEquatorialRadiusMeters_D = 6378137.0;
private static double latfac = wgs84_earthEquatorialRadiusMeters_D;
private static double lonfac = wgs84_earthEquatorialRadiusMeters_D;
final public static transient double HALF_PI_D = Math.PI/2.0d;
/**
* Returns google projection coordinates from wgs84 lat,long coordinates
*/
public static double[] forward(double lat, double lon) {
lat = normalizeLatitude(lat);
lon = wrapLongitude(lon);
double latrad = Math.toRadians(lat);
double lonrad = Math.toRadians(lon);
double lat_m = latfac * Math.log(Math.tan(((latrad + HALF_PI_D)/2d)));
double lon_m = lonfac * lonrad;
double[] x = { lon_m, lat_m };
return x;
}
/**
* Returns wgs84 lat,long coordinates from google projection coordinates
*/
public static float[] inverse(float lon_m, float lat_m) {
double latrad = (2d * Math.atan(Math.exp(lat_m/latfac))) - HALF_PI_D;
double lonrad = lon_m/lonfac;
double lat = Math.toDegrees(latrad);
double lon = Math.toDegrees(lonrad);
lat = normalizeLatitude(lat);
lon = wrapLongitude(lon);
float[] x = { (float) lat, (float) lon };
return x;
}
private static double wrapLongitude(double lon) {
if ((lon < -DATELINE) || (lon > DATELINE)) {
lon += DATELINE;
lon = lon % LON_RANGE;
lon = (lon < 0) ? DATELINE + lon : -DATELINE + lon;
}
return lon;
}
private static double normalizeLatitude(double lat) {
if (lat > NORTH_POLE) {
lat = NORTH_POLE;
}
if (lat < SOUTH_POLE) {
lat = SOUTH_POLE;
}
return lat;
}
}
+0
我已经看到一些公式将W GS84到EPSG 3785,他们也问半球和时区(子午线)? – 2013-06-06 02:49:34
我用wayback机器找到了它:http://web.archive.org/web/20110809084551/http://mapki.com/wiki/Tile_utility_code_in_Java – 2013-03-05 15:50:34