nearestPointOnLine function

Feature<Point> nearestPointOnLine(
  1. LineString line,
  2. Point point, [
  3. Unit unit = Unit.kilometers
])

Takes a Point and a LineString and calculates the closest Point on the LineString.

The properties of returned Point will contain three values:

  • index: closest point was found on nth line part
  • dist: distance between point and the closest point on line
  • location: distance along the line between start and the closest point.

Example:

var line = LineString(
  coordinates: [
    Position.of([-77.031669, 38.878605]),
    Position.of([-77.029609, 38.881946]),
    Position.of([-77.020339, 38.884084]),
    Position.of([-77.025661, 38.885821]),
    Position.of([-77.021884, 38.889563]),
    Position.of([-77.019824, 38.892368])
]);
var pt = Point(coordinates: Position(-77.037076, 38.884017));

var snapped = nearestPointOnLine(line, pt, Unit.miles);

Implementation

Feature<Point> nearestPointOnLine(
  LineString line,
  Point point, [
  Unit unit = Unit.kilometers,
]) {
  return _nearestPointOnLine(line, point, unit).toFeature();
}