LineString.build constructor

LineString.build(Iterable<double> chain, { Coords type = Coords.xy, Box? bounds, })

Builds a line string geometry from a chain of positions.

Use type to specify the type of coordinates, by default Coords.xy is expected.

An optional bounds can used set a minimum bounding box for a geometry.

The chain array must contain at least two positions (or be empty). It contains coordinate values of chain positions as a flat structure. For example for Coords.xyz the first three coordinate values are x, y and z of the first position, the next three coordinate values are x, y and z of the second position, and so on.

Examples:

// a line string from 2D positions
LineString.build(
  [
    10.0, 20.0, // (x, y) for position 0
    12.5, 22.5, // (x, y) for position 1
    15.0, 25.0, // (x, y) for position 2
  ],
  type: Coords.xy,
);

// a line string from 3D positions
LineString.build(
  [
    10.0, 20.0, 30.0, // (x, y, z) for position 0
    12.5, 22.5, 32.5, // (x, y, z) for position 1
    15.0, 25.0, 35.0, // (x, y, z) for position 2
  ],
  type: Coords.xyz,
);

// a line string from measured 2D positions
LineString.build(
  [
    10.0, 20.0, 40.0, // (x, y, m) for position 0
    12.5, 22.5, 42.5, // (x, y, m) for position 1
    15.0, 25.0, 45.0, // (x, y, m) for position 2
  ],
  type: Coords.xym,
);

// a line string from measured 3D positions
LineString.build(
  [
    10.0, 20.0, 30.0, 40.0, // (x, y, z, m) for position 0
    12.5, 22.5, 32.5, 42.5, // (x, y, z, m) for position 1
    15.0, 25.0, 35.0, 45.0, // (x, y, z, m) for position 2
  ],
  type: Coords.xyzm,
);

Implementation

factory LineString.build(
  Iterable<double> chain, {
  Coords type = Coords.xy,
  Box? bounds,
}) =>
    LineString(
      PositionSeries.view(
        chain is List<double> ? chain : toFloatNNList(chain),
        type: type,
      ),
      bounds: bounds,
    );