iOS - 确定坐标是否在 GMSPolyline 内

Question

我已经在使用GMSGeometryContainsLocation的方法了为了确定坐标(来自点击用户)是否在 GMSPolygon 内，但我不能让它适用于 GMSPolyline。

-(void) didTapOnPolyline:(CLLocationCoordinate2D)coordinate andMap:(GMSMapView *)mapView {
    if (_pathVS != nil) {
        for (id key in _pathVS) {
            if (GMSGeometryIsLocationOnPath(coordinate, [_pathVS objectForKey:key], YES)) {
                _myMarker = [GMSMarker markerWithPosition:coordinate];
                _myMarker.opacity = 1.f;
                // _myMarker.icon = [UIImage imageNamed:@"marker-maps"];

                _myMarker.map = mapView;
                _myMarker.userData = key;
                [_mapView setSelectedMarker:_myMarker];
            }
        }
    }
}

我从触发的委托(delegate)方法中调用此方法:

-(void) mapView:(GMSMapView *)mapView didTapAtCoordinate:(CLLocationCoordinate2D)coordinate
{
    if (_myMarker)
        _myMarker.map = nil;

    [self didTapOnPolygon:coordinate andMap:mapView];
    [self didTapOnPolyline:coordinate andMap:mapView];
}

Answer 1

如果点击点不在折线上，则 GMSGeometryIsLocationOnPath条件永远不会返回真。所以你必须使用 GMSGeometryIsLocationOnPathTolerance
谷歌地图 SDK 文档说

A point that is not equal to a vertex is on one side or the other of any path segment -- it can never be "exactly on the border"

BOOL GMSGeometryIsLocationOnPathTolerance (CLLocationCoordinate2D point, GMSPath *path, BOOL    geodesic, CLLocationDistance tolerance)

返回点是在路径上还是在路径附近，在以米为单位的指定容差范围内。