api:dk11:delphi:gislayervector.tgis_layervector.locate_tgis_point_double_boolean
Table of Contents
TGIS_LayerVector.Locate(TGIS_Point; Double; Boolean) method
DK11 for Delphi | GisLayerVector.TGIS_LayerVector.Locate | Overloads | Constructors | Fields | Methods | Properties | Events
Locates a shape.
Syntax
// Delphi public function Locate( const _ptg : TGIS_Point; const _prec : Double; const _visible : Boolean ) : TGIS_Shape; overload; virtual;
// C++ Builder public: virtual TGIS_Shape* Locate( TGIS_Point* const _ptg, const double _prec, const bool _visible ) /* overload */;
Parameters
| Name | Type | Description |
|---|---|---|
| _ptg | TGIS_Point | reference point /searching point/; if the layer has been attached to the Viewer then expected _ptg units are in a Viewer coordinate space; otherwise expected _ptg units are in a Layer coordinate space |
| _prec | Double | precision /not a longer distance than/; for points inside the polygon (if _prec >= 0) the distance will be multiply by 0.95 (to prefer points inside the polygon) but will not be bigger then _prec; for point distance will be multiplied by 0.9 to prefer points over lines and polygons _prec units are calculated same way as _ptg |
| _visible | Boolean | if true the only visible shapes will be evaluated; shapes turned of by query of hidden will be ignored |
Result
| Type | Description |
|---|---|
| TGIS_Shape | Found shape or nil. |
Remarks
Use this method to locate a shape that is closest to point _ptg but also on _prec distance. Internally it calls LocateEx method.
If locate is called upon active paint operations then result could be null. But Locate and paint process are using the same vector enumerator context.
It is recommended to check InPaint property before calling this Locate.
2024/07/07 01:07