DangleExtender

extends only the dangling (unconnected) ends of lines, leaving connected ends untouched.

How It Works

DangleExtender intersects the input lines and checks each line end to see whether another line meets it there. An end with no other line touching it is dangling; an end shared with another line is connected. This is done internally, so no upstream TopologyBuilder is needed.

Only dangling ends are extended. Each is lengthened by the Extension Length along the bearing of its final segment, so the line continues in the direction of that segment. Connected ends are left exactly as they are. This is the difference from a plain LineExtender: LineExtender can extend beginnings, ends, or both and separates the results, but it has no notion of whether an end is already attached to another line.

Extended lines are tagged with the _extended attribute set to true.

The transformer extends geometry only — it does not snap. To close a gap onto a target, follow it with a Snapper or AnchoredSnapper downstream. Because only dangling ends are extended, the snapping tolerance can be kept small, which avoids snapping to the wrong nearby feature in dense networks.

Input

The lines to process. Features that are not lines are routed to <Rejected>.

Output

Extended

Lines that had at least one dangling side extended. Each carries _extended set to true.

Unchanged

Lines that were not modified. This includes lines whose sides are all connected, and isolated lines when Handle Isolated Lines is set to Do not extend. Features on this port carry _extended set to false.

DanglingNodes

Point features marking the unconnected sides detected in the input network. They are produced as part of the internal analysis and exposed here so you can see where the loose sides are — for instance, to inspect them visually or to measure how far they sit from the features they should reach, which helps in choosing a snapping tolerance. These points carry no attributes linking them to their source line; they are a positional aid only.

\<Rejected>

Non-line input features, together with any features rejected by the transformer's internal processing.

Parameters

Extension Length

The distance each dangling end is extended. Specified in ground units — the same units as the input coordinates.

Handle Isolated Lines

Controls how isolated lines (lines whose ends are both dangling) are treated:

Do not extend — isolated lines pass through to Unchanged with _extended set to false.

Extend both sides — both sides are extended, and the line is output on Extended with _extended set to true.

Usage Notes

DangleExtender extends; it does not snap. Pair it with an anchored Snapper downstream to close the extended ends onto their targets.

Extending only dangling ends lets the downstream snapping tolerance stay small, which reduces the risk of connecting to the wrong feature in dense networks — for example, joining to an adjacent room on a digitized floor plan.