ee.Geometry.closestPoint

  • closestPoint() returns the nearest point on the right geometry to the left geometry, returning null if either input is empty.

  • If only one input is unbounded, an arbitrary point in the bounded input is returned, and if both are unbounded, an arbitrary point is returned.

  • It accepts an optional maxError for reprojection and an optional proj to define the projection for the operation, defaulting to spherical coordinates in meters if unspecified.

  • There is also a one-sided API: closestPointOnInputGeom that returns a feature representing the closest point only on the input geometry.

 Returns the point on the right input that is nearest to the left input. If either input is empty, null is returned. If both inputs are unbounded, an arbitrary point is returned. If one input is unbounded, an arbitrary point in the bounded input is returned.

UsageReturns
Geometry.closestPoint(right, maxError, proj)Object
ArgumentTypeDetails
this: leftGeometryThe geometry used as the left operand of the operation.
rightGeometryThe geometry used as the right operand of the operation.
maxErrorErrorMargin, default: nullThe maximum amount of error tolerated when performing any necessary reprojection.
projProjection, default: nullThe projection in which to perform the operation. If not specified, the operation will be performed in a spherical coordinate system, and linear distances will be in meters on the sphere.

Examples

Code Editor (JavaScript)

// Define a Geometry object.
var geometry = ee.Geometry({
  'type': 'Polygon',
  'coordinates':
    [[[-122.081, 37.417],
      [-122.086, 37.421],
      [-122.084, 37.418],
      [-122.089, 37.416]]]
});

// Define other inputs.
var inputGeom = ee.Geometry.Polygon(
        [[[-122.068, 37.418],
          [-122.068, 37.416],
          [-122.064, 37.416],
          [-122.064, 37.418]]]);

// Apply the closestPoints method to the Geometry objects.
var closestPoints = ee.Dictionary(geometry.closestPoints({'right': inputGeom, 'maxError': 1}));

// Print the result to the console.
print('geometry.closestPoints(...) =', closestPoints);

// There is also a one-sided API for convenience.
var closestPointOnInputGeom = geometry.closestPoint({'right': inputGeom, 'maxError': 1});
print('geometry.closestPoint(...) =', closestPointOnInputGeom);

// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(geometry,
             {'color': 'black'},
             'Geometry [black]: geometry');
Map.addLayer(inputGeom,
             {'color': 'blue'},
             'Parameter [blue]: inputGeom');
Map.addLayer(closestPoints.getGeometry('left'),
             {'color': 'red'},
             'Result [red]: closestPointOnLeft');
Map.addLayer(closestPoints.getGeometry('right'),
             {'color': 'red'},
             'Result [red]: closestPointOnRight');