如何测试纬度/经度点是否在地图内（不是谷歌地图）

Question

如果我有一个定义地图的类，其顶部/左侧由经度和纬度定义，底部/右侧也由经度和纬度定义，如何测试给定的纬度/经度是否在地图的范围内边界点？ {这与谷歌地图无关）。 例如（在从 Tallhasse 到迈阿密的地图中是奥兰多）。

公共类 MapContext {

private Location mMapTop = null;
private Location mMapBottom = null;



public MapContext(String topLatitude,String topLongitude, String bottomLatitude, String bottomLongitude) {


    double theTopLat = Location.convert(topLatitude);
    double theTopLong = Location.convert(topLongitude);
    mMapTop = new Location("private");
    mMapTop.setLongitude(theTopLong);
    mMapTop.setLatitude(theTopLat);

    double theBottomLat = Location.convert(bottomLatitude);
    double theBottomLong = Location.convert(bottomLongitude);
    mMapBottom = new Location("private");
    mMapBottom.setLongitude(theBottomLong);
    mMapBottom.setLatitude(theBottomLat);

} 公共布尔testIfPointOnMap（位置位置）{ ? ? 返回 TRUE 或 FALSE } }

Answer 1

你能检查一下经纬度是否在界限之间吗？

   /*
    * top: north latitude of bounding box.
    * left: left longitude of bounding box (western bound). 
    * bottom: south latitude of the bounding box.
    * right: right longitude of bounding box (eastern bound).
    * latitude: latitude of the point to check.
    * longitude: longitude of the point to check.
    */
    boolean isBounded(double top, double left, 
                      double bottom, double right, 
                      double latitude, double longitude){
            /* Check latitude bounds first. */
            if(top >= latitude && latitude >= bottom){
                    /* If your bounding box doesn't wrap 
                       the date line the value
                       must be between the bounds.
                       If your bounding box does wrap the 
                       date line it only needs to be  
                       higher than the left bound or 
                       lower than the right bound. */
                if(left <= right && left <= longitude && longitude <= right){
                    return true;
                } else if(left > right && (left <= longitude || longitude <= right)) {
                    return true;
                }
            }
            return false;
    }

Answer 2

请发布您的代码 - 但假设您有这样的东西：

public class Map{
  public int x1, y1, x2, y2;
}

你的支票会很简单：

boolean isPointInMap(Map m, int x, int y){
  return m.x1 <= x && x <= m.x2 && m.y1 <= y && y <= m.y2;
}

Answer 3

这是一个完整的 Java 类，用于指定边界框并检查点是否位于其中。该框由其西南和东北地理坐标（纬度和经度）定义。

class Bbox
{
    public double swLatitude  = 0.0;
    public double swLongitude = 0.0;
    public double neLatitude  = 0.0;
    public double neLongitude = 0.0;

    /*************************************************************************
    Constructor.
    @param bboxSpecification A comma-separated string containing the 
        southwest latitude, soutwest longitude, northest latitude, and 
        northest longitude.
    *************************************************************************/
    public Bbox(String bboxSpecification)
    {
        String tokens[] = bboxSpecification.split("(?:,\\s*)+");

        if (tokens.length != 4)
        {
            throw new IllegalArgumentException(
                String.format("Expected 4 values in bbox string but found %d: %s\n",
                tokens.length, bboxSpecification));
        }

        swLatitude =  Double.parseDouble(tokens[0]);
        swLongitude = Double.parseDouble(tokens[1]);
        neLatitude =  Double.parseDouble(tokens[2]);
        neLongitude = Double.parseDouble(tokens[3]);
    }

    @Override
    public String toString()
    {
        return String.format("swLatitude=%f, swLongitude=%f, neLatitude=%f, neLongitude=%f", 
                swLatitude, swLongitude, neLatitude, neLongitude);
    }

    /*************************************************************************
    Checks if the bounding box contains the latitude and longitude. Note that
    the function works if the box contains the prime merdian but does not
    work if it contains one of the poles. 
    *************************************************************************/
    public boolean contains(double latitude, double longitude)
    {
        boolean longitudeContained = false;
        boolean latitudeContained = false;

        // Check if the bbox contains the prime meridian (longitude 0.0).
        if (swLongitude < neLongitude)
        {
            if (swLongitude < longitude && longitude < neLongitude)
            {
                longitudeContained = true;
            }
        }
        else
        {
            // Contains prime meridian.
            if ((0 < longitude && longitude < neLongitude) ||
                (swLongitude < longitude && longitude < 0))
            {
                longitudeContained = true;
            }
        }

        if (swLatitude < neLatitude)
        {
            if (swLatitude < latitude && latitude < neLatitude)
            {
                latitudeContained = true;
            }
        }
        else 
        {
            // The poles. Don't care.
        }

        return (longitudeContained && latitudeContained);
    }

    public static void test()
    {
        Bbox bbox;
        double latitude = 0;
        double longitude = 0;

        bbox = new Bbox("37.43, -122.38, 37.89, -121.98");
        latitude = 37.5;
        longitude = -122.0;

        System.out.printf("bbox (%s) contains %f, %f: %s\n", 
            bbox, latitude, longitude, bbox.contains(latitude, longitude));

        bbox = new Bbox("50.99, -2.0, 54, 1.0");
        latitude = 51.0;
        longitude = 0.1;

        System.out.printf("bbox (%s) contains %f, %f: %s\n", 
            bbox, latitude, longitude, bbox.contains(latitude, longitude));
    }
}

Answer 4

没有找到完美的解决方案，但使用简单的边界检查是可以的，因为缩放级别越来越精确，位置的变化变得越来越不明显。没有我想要的那么精确，但在 GPS 精度范围内。