public override bool IsInsideDataArea {get;}

{
  // is the node "inside"
  var isInsideNode = node.IsInsideDataArea;

  // get all other nodes connected to "node" 
  IReadOnlyList<ArcGIS.Core.Data.Analyst3D.TinNode> adjNodes = node.GetAdjacentNodes();

  // get all edges that share "node" as a from node. 
  IReadOnlyList<ArcGIS.Core.Data.Analyst3D.TinEdge> edges = node.GetIncidentEdges();

  // get all triangles that share "node"
  IReadOnlyList<ArcGIS.Core.Data.Analyst3D.TinTriangle> triangles = node.GetIncidentTriangles();
}