Java 的纬度/经度和距离问题

Question

我试图让一部分代码正常工作（类似于我下面的代码），以便 OBJECT_LOC 和 CONVERTED_LOC 完全相同。我认为代码与我正在做的事情非常简单，但由于某种原因它们的结果并不相同？我做错了什么？ （您可以在下面看到输出）。

import com.bbn.openmap.LatLonPoint;
import com.bbn.openmap.proj.Length;
import com.bbn.openmap.proj.coords.DMSLatLonPoint;

public class Test {

       /**
        * @param args
        */
       public static void main(String[] args) {

               // 45:20:00.0N/24:00:00.0E
               LatLonPoint BASE_LOC = new DMSLatLonPoint(false, 45, 20, 00.0f, false,
                               24, 00, 00.0f).getLatLonPoint();

               System.out.println("BASE_LOC: " + BASE_LOC);

               LatLonPoint OBJECT_LOC = new LatLonPoint(52.749355, 26.346556);

               System.out.println("OBJECT_LOC: " + OBJECT_LOC);

               float distanceX = BASE_LOC.distance(new LatLonPoint(BASE_LOC
                               .getLatitude(), OBJECT_LOC.getLongitude()));

               float distanceY = BASE_LOC.distance(new LatLonPoint(OBJECT_LOC
                               .getLatitude(), BASE_LOC.getLongitude()));


               LatLonPoint CONVERTED_POINT = new LatLonPoint(BASE_LOC.getLatitude()
                               + Length.DECIMAL_DEGREE.fromRadians(distanceY),
                               BASE_LOC.getLongitude()
                                               + Length.DECIMAL_DEGREE.fromRadians(distanceX));

               System.out.println("CONVERTED_POINT " + CONVERTED_POINT);

       }
}

输出：

BASE_LOC: LatLonPoint[lat=45.333332,lon=24.0]
OBJECT_LOC: LatLonPoint[lat=52.749355,lon=26.346556]
CONVERTED_POINT LatLonPoint[lat=52.749355,lon=25.649527]

Answer 1

在查看了 API 文档和一些地理文献之后，您发现第二点的方法似乎有缺陷。正确的方法是使用距离和方位角（方位角）。以下是更正后的代码：

import com.bbn.openmap.LatLonPoint;
import com.bbn.openmap.proj.coords.DMSLatLonPoint;

public class TestProgram {

   /**
    * @param args
    */
   public static void main(String[] args) {

           // 45:20:00.0N/24:00:00.0E
           LatLonPoint BASE_LOC = new DMSLatLonPoint(false, 45, 20, 00.0f, false, 24, 00, 00.0f).getLatLonPoint();
           System.out.println("BASE_LOC: " + BASE_LOC);

           LatLonPoint OBJECT_LOC = new LatLonPoint(52.749355, 26.0);
           System.out.println("OBJECT_LOC: " + OBJECT_LOC);

           float distance = BASE_LOC.distance(OBJECT_LOC);
           float az = BASE_LOC.azimuth(OBJECT_LOC);

           LatLonPoint CONVERTED_POINT = BASE_LOC.getPoint(distance, az);

           System.out.println("CONVERTED_POINT " + CONVERTED_POINT);

   }

}

此处提供了一些信息 - http://www. move-type.co.uk/scripts/latlong.html

Answer 2

无论如何，当您执行 BASE_LOC.distance() 调用时，您将在两个距离的参数中的 OBJECT_LOC/BASE_LOC 之间进行交换。其中一个为 OBJECT_LOC/BASE_LOC，另一个为 BASE_LOC/OBJECT_LOC。