The Esri TinTriangle component.
The TinTriangle object is one of the three basic elements of a TIN: nodes, edges, and triangles. Triangles are comprised of three nodes and edges. Nodes and edges are ordered in a clockwise direction.
The data area of a TIN is controlled through triangle masking. Every triangle has a mask bit that indicates whether the triangle is inside the data area (or interpolation zone). It's an editable property. ITinElement, and its inherited interface ITinTriangle, provide read-only access to this property via IsInsideDataArea. ITinAdvanced2.IsTriangleInsideDataArea can also be used for read access and is preferential in many cases because it hands the TIN object a triangle index number to use and does not incur the overhead of dealing with TinTriangle objects. ITinEdit.SetTriangleInsideDataArea is used to write the property. Also, ITinEdit.AddFromFeatureClass and ITinEdit's AddShape/AddShapeZ have the ability to add polygon geometry as clip or erase surface feature types. Triangles falling outside a clip feature are masked as outside. Erase features mask triangles that are inside them.
Extended Error Information
Use the ISupportErrorInfo method InterfaceSupportsErrorInfo to determine if the object supports extended error information. If the object supports extended error info, VC++ developers should use the OLE/COM IErrorInfo interface to access the ErrorInfo object. Visual Basic developers should use the global error object Err to retrieve this extended error information.
|ISupportErrorInfo||Indicates whether a specific interface can return Automation error objects.|
|ITinElement||Provides access to members to control TIN elements.|
|ITinFeatureSeed||Provides access to control TIN elements' properties.|
|ITinTriangle||Provides access to members that control TIN triangles.|