getVisualPortOrigin method

Offset getVisualPortOrigin(String portId, { required Size portSize, NodeShape? shape, })

Gets the visual position where a port should be rendered within the node container.

Gets the visual origin (top-left corner) of a port within this node's local coordinate space.

The origin is where the port widget's top-left corner should be positioned. Port widgets are positioned so their outer edge aligns with the node boundary.

Parameters:

• portId - The unique identifier of the port
• portSize - The size of the port widget (width x height)
• shape - Optional shape for anchor-based positioning

Returns the Offset where the port widget's top-left corner should be positioned.

Throws ArgumentError if no port with the given portId is found.

See also:

• getConnectionPoint for the connection attachment position
• getPortCenter for the visual center position

Implementation

Offset getVisualPortOrigin(
  String portId, {
  required Size portSize,
  NodeShape? shape,
}) {
  final port = [
    ...inputPorts,
    ...outputPorts,
  ].cast<Port?>().firstWhere((p) => p?.id == portId, orElse: () => null);

  if (port == null) {
    throw ArgumentError('Port $portId not found');
  }

  // Get anchor position from shape (full node size) or default edge centers
  final Offset anchorOffset;
  if (shape != null) {
    final anchors = shape.getPortAnchors(size.value);
    final anchor = anchors.firstWhere(
      (a) => a.position == port.position,
      orElse: () => _fallbackAnchor(port.position),
    );
    anchorOffset = anchor.offset;
  } else {
    anchorOffset = _fallbackAnchor(port.position).offset;
  }

  // Use centralized calculation from PortPosition extension
  return port.position.calculateOrigin(
    anchorOffset: anchorOffset,
    portSize: portSize,
    portAdjustment: port.offset,
    useAnchorForPerpendicularAxis: shape != null,
  );
}