The polygon builder allows you to create and modify Polygon geometries incrementally. More...
| Header: | #include <PolygonBuilder.h> |
| Since: | Esri::ArcGISRuntime 100.0 |
| Inherits: | Esri::ArcGISRuntime::MultipartBuilder |
Public Functions
| PolygonBuilder(const Esri::ArcGISRuntime::SpatialReference &spatialReference, QObject *parent = nullptr) | |
| PolygonBuilder(const Esri::ArcGISRuntime::Polygon &polygon, QObject *parent = nullptr) | |
| virtual | ~PolygonBuilder() override |
| Esri::ArcGISRuntime::Polygon | toPolygon() const |
| Esri::ArcGISRuntime::Polyline | toPolyline() const |
Reimplemented Public Functions
| virtual Esri::ArcGISRuntime::GeometryBuilderType | geometryBuilderType() const override |
| virtual Esri::ArcGISRuntime::Geometry | toGeometry() const override |
Detailed Description
Polygon geometries are immutable and cannot be changed directly once created. A polygon is a closed area shape defined by one or more parts. Each part in a polygon is a connected sequence of Segment instances that start and end at the same point (a closed ring). If a polygon has more than one ring, the rings may be separate from one another or they may nest inside one another, but they should not overlap. Note: interior rings, to make donut polygons, should be counter-clockwise in direction to be topology correct. If there is ever a doubt about the topological correctness of a polygon, call GeometryEngine::simplify(const Esri::ArcGISRuntime::Geometry&) to correct any issues.
The polygon builder allows you to change the contents of the shape using the PartCollection that you can access from the MultipartBuilder::parts. Each Part, in this PartCollection, comprises a collection of segments that make edges of the Part. You can add or remove a Part from the PartCollection, or you can create a new or edit the segment vertices of an existing Part. Use GeometryBuilder::toGeometry to return the new Polygon from the builder.
// create a polygon builder PolygonBuilder* polygonBuilder = new PolygonBuilder(SpatialReference(3857), this); // create a single-part polygon using x/y polygonBuilder->addPoint(-18.0, 34.0); polygonBuilder->addPoint(-18.0, 35.0); polygonBuilder->addPoint(-17.0, 34.0); Polygon singlePartPolygonXY(polygonBuilder->toGeometry()); // create a multi-part polygon with same PolygonBuilder PartCollection* partCollection = new PartCollection(polygonBuilder->spatialReference(), this); // create outer poly 1 Part* part1 = new Part(polygonBuilder->spatialReference(), this); part1->addPoint(2.123456789, 3.123456789); part1->addPoint(1.123456789, 3.123456789); part1->addPoint(1.123456789, 1.123456789); partCollection->addPart(part1); // create outer poly 2 Part* part2 = new Part(polygonBuilder->spatialReference(), this); part2->addPoint(3.123456789, 3.123456789); part2->addPoint(4.123456789, 3.123456789); part2->addPoint(4.123456789, 1.123456789); partCollection->addPart(part2); polygonBuilder->setParts(partCollection); Polygon multipartPolygon = polygonBuilder->toPolygon();
Member Function Documentation
[explicit] PolygonBuilder::PolygonBuilder (const Esri::ArcGISRuntime::SpatialReference &spatialReference , QObject *parent = nullptr)
Creates a new empty polygon builder with the specified SpatialReference.
- spatialReference - The builder's spatial reference.
- parent - The optional parent QObject.
The SpatialReference cannot be changed after instantiation.
See also GeometryBuilder::hasCurves.
[explicit] PolygonBuilder::PolygonBuilder (const Esri::ArcGISRuntime::Polygon &polygon, QObject *parent = nullptr)
Creates a new polygon builder by copying the parts from the specified Polygon.
- polygon - A polygon used to initialize the new builder.
- parent - The optional parent QObject.
The SpatialReference of the new polygon builder will match that of the given Polygon. Use this constructor in workflows that create a modified version of an existing geometry. Polygons with curves are supported.
See also GeometryBuilder::hasCurves.
[override virtual] PolygonBuilder::~PolygonBuilder ()
Destructor.
[override virtual] Esri::ArcGISRuntime::GeometryBuilderType PolygonBuilder::geometryBuilderType () const
Reimplements: GeometryBuilder::geometryBuilderType() const.
Returns the GeometryBuilderType of this builder.
[override virtual] Esri::ArcGISRuntime::Geometry PolygonBuilder::toGeometry () const
Reimplements: GeometryBuilder::toGeometry() const.
Returns the Polygon geometry this builder is constructing or modifying.
Esri::ArcGISRuntime::Polygon PolygonBuilder::toPolygon () const
Returns the Polygon geometry this builder is constructing or modifying.
This is a convenience method to avoid casting the return value.
Esri::ArcGISRuntime::Polyline PolygonBuilder::toPolyline () const
Returns a polyline with the values in the polygon builder.