api:dk11:delphi:gishydrology.tgis_hydrology.streamtopolyline_tgis_layerpixel_tgis_layerpixel_tgis_extent_tgis_layervector_string_integer
Table of Contents
TGIS_Hydrology.StreamToPolyline method
DK11 for Delphi | GisHydrology.TGIS_Hydrology.StreamToPolyline | Constructors | Methods | Events
Converts a stream network to polylines.
Syntax
// Delphi public procedure StreamToPolyline( const _flowDir : TGIS_LayerPixel; const _streamsPix : TGIS_LayerPixel; const _extent : TGIS_Extent; const _streamsVec : TGIS_LayerVector; const _orderField : String = STREAM_POLYLINE_FIELD; const _threshold : Integer = STREAM_POLYLINE_THRESHOLD );
// C++ Builder public: void StreamToPolyline( TGIS_LayerPixel* const _flowDir, TGIS_LayerPixel* const _streamsPix, TGIS_Extent* const _extent, TGIS_LayerVector* const _streamsVec, const UnicodeString _orderField, const int _threshold );
Parameters
| Name | Type | Description |
|---|---|---|
| _flowDir | TGIS_LayerPixel | an input flow direction grid |
| _streamsPix | TGIS_LayerPixel | an input grid representing a stream network |
| _extent | TGIS_Extent | an extent to be processed |
| _streamsVec | TGIS_LayerVector | the output vector layer |
| _orderField | String | an optional numerical field from _streamsVec to populate stream network value (flow accumulation, or stream order value from grid); default parameter is empty string, this means that no attribute information is transferred to vector layer |
| _threshold | Integer | use this property to limit processed cells from stream network; default parameter is 0 |
Remarks
The stream network is represented by flow accumulation, or stream order grid. If the flow accumulation grid is used, recommended threshold is 1% of the maximum value from the flow accumulation grid.
References
2021/05/26 01:14