ITinEdit.InitNew Method

Initializes a new TIN using the passed extent to define the data area.

[Visual Basic .NET]
Public Sub InitNew ( _
    ByVal pExtent As IEnvelope _
)

[C#]
public void InitNew (
    IEnvelope pExtent
);

[C++]
HRESULT InitNew(
  IEnvelope* pExtent
);

[C++]
Parameters
pExtent [in]

  pExtent is a parameter of type IEnvelope*

Product Availability

Description

The envelope, pExtent, defines the intended 2D domain of the TIN. Data subsequently added to the triangulation should fall within this extent. Four software synthesized nodes (called super nodes) will be used to form an initial triangulation. These will be positioned outside the declared extent. You should be fairly accurate with the extent so the positions of the super nodes is estimated correctly. Providing an unnecessarily large extent would result in the nodes being placed farther away than necessary from the data which can hurt performance and increase the likelihood of precision related issues.

If the envelope has a spatial reference it will be copied and assigned to the TIN. If there is a spatial reference it should have a Z domain/resolution defined. This is particularly true if you will be doing anything with the TIN other than simply adding features to it and saving to disk. Some operations on TIN use the geometry topology engine and these require a z domain when z-aware geometry is involved. Some spatial references are not supported by the prj file saved with a TIN for the sake of compatibility with workstation Arc/INFO. If a spatial reference is used that's not supported by workstation Arc/INFO a call to ITinEdit.SaveAs will exclude the prj file.

InitNew will automatically place the TIN in edit mode as there is an assumption that edits are about to take place.

See Also

.NET Samples