RelateComputer class

Computes the topological relationship between two Geometries.

RelateComputer does not need to build a complete graph structure to compute the IntersectionMatrix. The relationship between the geometries can be computed by simply examining the labelling of edges incident on each node.

RelateComputer does not currently support arbitrary GeometryCollections. This is because GeometryCollections can contain overlapping Polygons. In order to correct compute relate on overlapping Polygons, they would first need to be noded and merged (if not explicitly, at least implicitly).

@version 1.7

Constructors

RelateComputer(List<GeometryGraph> arg)

Properties

arg ↔ List<GeometryGraph>

getter/setter pair

hashCode → int

The hash code for this object.

no setter, inherited

im ↔ IntersectionMatrix?

getter/setter pair

invalidPoint ↔ Coordinate?

getter/setter pair

isolatedEdges ↔ List

getter/setter pair

li ↔ LineIntersector

getter/setter pair

nodes ↔ NodeMap

getter/setter pair

ptLocator ↔ PointLocator

getter/setter pair

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

computeDisjointIM(IntersectionMatrix im) → void

If the Geometries are disjoint, we need to enter their dimension and boundary dimension in the Ext rows in the IM

computeIM() → IntersectionMatrix

computeIntersectionNodes(int argIndex) → void

Insert nodes for all intersections on the edges of a Geometry. Label the created nodes the same as the edge label if they do not already have a label. This allows nodes created by either self-intersections or mutual intersections to be labelled. Endpoint nodes will already be labelled from when they were inserted.

computeProperIntersectionIM(SegmentIntersector intersector, IntersectionMatrix im) → void

copyNodesAndLabels(int argIndex) → void

Copy all nodes from an arg geometry into this graph. The node label in the arg geometry overrides any previously computed label for that argIndex. (E.g. a node may be an intersection node with a computed label of BOUNDARY, but in the original arg Geometry it is actually in the interior due to the Boundary Determination Rule)

insertEdgeEnds(List ee) → void

labelIntersectionNodes(int argIndex) → void

For all intersections on the edges of a Geometry, label the corresponding node IF it doesn't already have a label. This allows nodes created by either self-intersections or mutual intersections to be labelled. Endpoint nodes will already be labelled from when they were inserted.

labelIsolatedEdge(Edge e, int targetIndex, Geometry target) → void

Label an isolated edge of a graph with its relationship to the target geometry. If the target has dim 2 or 1, the edge can either be in the interior or the exterior. If the target has dim 0, the edge must be in the exterior

labelIsolatedEdges(int thisIndex, int targetIndex) → void

Processes isolated edges by computing their labelling and adding them to the isolated edges list. Isolated edges are guaranteed not to touch the boundary of the target (since if they did, they would have caused an intersection to be computed and hence would not be isolated)

labelIsolatedNode(Node n, int targetIndex) → void

Label an isolated node with its relationship to the target geometry.

labelIsolatedNodes() → void

Isolated nodes are nodes whose labels are incomplete (e.g. the location for one Geometry is null). This is the case because nodes in one graph which don't intersect nodes in the other are not completely labelled by the initial process of adding nodes to the nodeList. To complete the labelling we need to check for nodes that lie in the interior of edges, and in the interior of areas.

labelNodeEdges() → void

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

updateIM(IntersectionMatrix im) → void

update the IM with the sum of the IMs for each component

Operators

operator ==(Object other) → bool

The equality operator.

inherited