ITinAdvanced.ExtractPolygon Method

Returns a polygon definition based on all contiguous triangles having the same filter criteria.

[Visual Basic .NET]
Public Function ExtractPolygon ( _
    ByVal pSeed As ITinElement, _
    ByVal pFilter As ITinFilter, _
    ByVal bStopAtEnforcedEdge As Boolean _
) As ITinPolygon

[C#]
public ITinPolygon ExtractPolygon (
    ITinElement pSeed,
    ITinFilter pFilter,
    bool bStopAtEnforcedEdge
);

[C++]
HRESULT ExtractPolygon(
  ITinElement* pSeed,
  ITinFilter* pFilter,
  VARIANT_BOOL bStopAtEnforcedEdge,
  ITinPolygon** ppPolygon
);

[C++]

Parameters
pSeed [in]

  pSeed is a parameter of type ITinElement
pFilter [in]

  pFilter is a parameter of type ITinFilter
bStopAtEnforcedEdge [in]
  bStopAtEnforcedEdge is a parameter of type VARIANT_BOOL
ppPolygon [out, retval]

  ppPolygon is a parameter of type ITinPolygon

Product Availability

Description

Returns a TinPolygon that references the polygon defined by the input seed and filter.

The seed is a TIN triangle that falls within the desired polygon or a TIN edge that falls on its boundary. An edge seed can only extract a single part polygon without holes.

The filter defines the criteria used to extract the polygon. Starting from a triangle based seed outward, all triangles that can pass through the filter are considered part of the polygon (the inside). If an edge is given as a seed, connected edges that pass through the filter are used to define the polygon boundary.

The filter argument can be NULL ('Nothing' in VB) if the seed is a triangle. A filter is required if the seed is an edge.

Use no filter with the bStopAtEnforcedEdge argument set to TRUE to extract polygons whose definition is that they are enclosed by breaklines. Be careful, no filter with bStopAtEnforcedEdge set to FALSE is guaranteed to return all triangles in the TIN. Also, while an area may look closed it may not actually be. This can return many more triangles than expected.

See Also