GeometryCollection<E extends Geometry>.build constructor
GeometryCollection<E extends Geometry>.build (
- WriteGeometries geometries, {
- Coords? type,
- int? count,
- Box? bounds,
Builds a geometry collection from the content provided by geometries
.
Only geometry objects of E
are built, any other geometries are ignored.
An optional type
specifies the coordinate type of geometry objects in a
collection. When not provided, the type can be resolved from objects.
An optional expected count
, when given, specifies the number of geometry
objects in a content stream. Note that when given the count MUST be exact.
An optional bounds
can used set a minimum bounding box for a geometry
collection.
Examples:
GeometryCollection.build(
count: 3,
(GeometryContent geom) {
geom
// a point with a 2D position
..point([10.0, 20.0].xy)
// a point with a 3D position
..point([10.0, 20.0, 30.0].xyz)
// a line string from three 3D positions
..lineString(
[
10.0, 20.0, 30.0,
12.5, 22.5, 32.5,
15.0, 25.0, 35.0,
//
].positions(Coords.xyz),
);
},
);
Implementation
factory GeometryCollection.build(
WriteGeometries geometries, {
Coords? type,
int? count,
Box? bounds,
}) =>
GeometryCollection<E>(
GeometryBuilder.buildList<E>(geometries, count: count),
bounds: bounds,
type: type,
);