我想画一个中心GPS点和两个终点GPS点的弧.我可以使用任何可以与
android搭配使用的地图软件.
到目前为止,我已经尝试过Google Maps for Android. Android的MapBox ARCGIS for Android.他们似乎都不能做这个简单的任务.
我猜想我需要一些叠加层？
解决方法
首先,您必须更改地理数据表示.
由此：
36°46'02.5"S 174°50'03.6"E GRC 36°56'18.3"S 174°33'09.7"E CWA 36°52'19.2"S 174°29'23.5"E 5.0' NM 36°48'19.8"S 174°25'37.7"E GRC 36°41'06.1"S 174°37'32.9"E CCA 36°39'54.5"S 174°38'40.7"E 1.5' NM 36°41'00.3"S 174°39'57.1"E GRC 36°39'49.4"S 174°41'32.3"E CCA 36°38'43.5"S 174°40'15.7"E 1.5' NM 36°39'17.5"S 174°41'59.7"E GRC 36°39'38.6"S 174°44'37.7"E GRC 36°37'08.8"S 174°47'27.4"E CWA 36°42'03.8"S 174°46'17.0"E 5.0' NM
为此：
-36.76736 174.83433 GRC -36.93842 174.55269 CWA -36.87200 174.48986 0.08333 NM -36.80550 174.42714 GRC -36.68503 174.62581 CCA -36.66514 174.64464 0.02500 NM -36.68342 174.66586 GRC -36.66372 174.69231 CCA -36.64542 174.67103 0.02500 NM -36.65486 174.69992 GRC -36.66072 174.74381 GRC -36.61911 174.79094 CWA -36.70106 174.77139 0.08333 NM
然后,您可以使用它们来构建路径(例如,SVG path)：
<svg
...>
<g
transform="matrix(1250,1250,46206.909,-217995.49)"
...>
<path
d=" M -36.76736,174.83433 L -36.93842,174.55269 A 0.08333,0.08333 0 0,1 -36.80550,174.42714 L -36.68503,174.62581 A 0.02500,0.02500 0 0,0 -36.68342,174.66586 L -36.66372,174.69231 A 0.02500,0 -36.65486,174.69992 L -36.66072,174.74381 L -36.61911,174.79094 A 0.08333,1 -36.76736,174.83433 Z"
.../>
</g>
</svg>
实际上,没有API可以在GMaps / OSMDroid中创建曲线,弧等,所以你应该画几条小线.这意味着做一些数学,但这个数学可以由GeographicLib library做出：
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
MapView map = (MapView) findViewById(R.id.map);
map.setTileSource(TileSourceFactory.MAPNIK);
map.setBuiltInZoomControls(true);
map.setMultiTouchControls(true);
IMapController mapController = map.getController();
mapController.setZoom(9);
GeoPoint startPoint = new GeoPoint(-36.66372,174.69231);
mapController.setCenter(startPoint);
Polygon polyline = new Polygon(this);
List<GeoPoint> points = new LinkedList<>();
// I filled the data manually,but it can be done more clever,of course.
GRC(points,new GeoPoint(-36.76736,174.83433));
CWA(points,new GeoPoint(-36.93842,174.55269),new GeoPoint(-36.87200,174.48986),new GeoPoint(-36.80550,174.42714),0.08333);
CCA(points,new GeoPoint(-36.68503,174.62581),new GeoPoint(-36.66514,174.64464),new GeoPoint(-36.68342,174.66586),0.02500);
CCA(points,new GeoPoint(-36.66372,174.69231),new GeoPoint(-36.64542,174.67103),new GeoPoint(-36.65486,174.69992),0.02500);
GRC(points,new GeoPoint(-36.66072,174.74381));
CWA(points,new GeoPoint(-36.61911,174.79094),new GeoPoint(-36.70106,174.77139),174.83433),//close shape going to the start point
0.08333);
polyline.setPoints(points);
polyline.setFillColor(0xA0FF00FF);
polyline.setStrokeColor(Color.BLACK);
polyline.setStrokeWidth(2f);
map.getOverlays().add(polyline);
map.invalidate();
}
private void CCA(List<GeoPoint> points,GeoPoint startPoint,GeoPoint centerPoint,GeoPoint endPoint,double radius) {
points.add(startPoint);
GeodesicData f = Geodesic.WGS84.Inverse(centerPoint.getLatitude(),centerPoint.getLongitude(),startPoint.getLatitude(),startPoint.getLongitude());
GeodesicData t = Geodesic.WGS84.Inverse(centerPoint.getLatitude(),endPoint.getLatitude(),endPoint.getLongitude());
double ffaz = f.azi1;
double tfaz = t.azi1;
final int decrement = 1;
while (Math.abs((int)ffaz) != Math.abs((int)tfaz)) {
GeodesicData llb = Geodesic.WGS84.Direct(centerPoint.getLatitude(),ffaz,f.s12);
points.add(new GeoPoint(llb.lat2,llb.lon2));
ffaz -= decrement;
if (ffaz <0) {
ffaz += 360;
}
}
points.add(endPoint);
}
private void CWA(List<GeoPoint> points,endPoint.getLongitude());
double ffaz = f.azi1;
double tfaz = t.azi1 > 0 ? t.azi1 : 360 + t.azi1;
final int increment = 1;
while (Math.abs((int)ffaz) != Math.abs((int)tfaz)) {
GeodesicData llb = Geodesic.WGS84.Direct(centerPoint.getLatitude(),llb.lon2));
ffaz += increment;
if (ffaz>360) {
ffaz -= 360;
}
}
points.add(endPoint);
}
private void GRC(List<GeoPoint> points,GeoPoint geoPoint) {
points.add(geoPoint);
}
我使用osmdroid OSMBonusPack,但代码是相当普遍的,可以轻松地与Google地图一起使用.
结果：
另外,你会介意告诉你发布了哪个地理数据？地图上的形状看起来像一个允许的飞行区域,我猜.
