hitTest method

HitTestResult hitTest(Offset point)

Performs hit testing at a point.

Tests in priority order matching visual z-order (top to bottom): foreground nodes (CommentNode) → ports → middle nodes → connections → background nodes (GroupNode) → canvas

This order ensures that elements visually on top receive hit priority. Foreground nodes (comments) are above everything except the interaction layer. Background nodes (groups) are behind regular nodes and connections.

Implementation

HitTestResult hitTest(Offset point) {
  // 1. Foreground nodes (CommentNode - highest priority, visually on top)
  final foregroundResult = _hitTestNodesByLayer(
    point,
    layer: NodeRenderLayer.foreground,
  );
  if (foregroundResult != null) return foregroundResult;

  // 2. Ports
  final portResult = _hitTestPorts(point);
  if (portResult != null) return portResult;

  // 3. Middle layer nodes (regular nodes)
  final nodeResult = _hitTestNodesByLayer(
    point,
    layer: NodeRenderLayer.middle,
  );
  if (nodeResult != null) return nodeResult;

  // 4. Connections
  final connectionResult = _hitTestConnections(point);
  if (connectionResult != null) return connectionResult;

  // 5. Background nodes (GroupNode - behind regular nodes/connections)
  final backgroundResult = _hitTestNodesByLayer(
    point,
    layer: NodeRenderLayer.background,
  );
  if (backgroundResult != null) return backgroundResult;

  // 6. Canvas (background)
  return const HitTestResult(hitType: HitTarget.canvas);
}