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Home GeoPack GeoMap Class TGeoMap Events OnSelectRect
See also: TSelectRectEvent, MouseAction 

OnSelectRect


Unit:SDL_geomap
Class:TGeoMap
Declaration: OnSelectRect: TSelectRectEvent;
{TSelectRectEvent = procedure (Sender: TObject; Layer: integer; LoX, LoY, HiX, HiY: double) of object;}

The event OnSelectRect is triggered when the left mouse button is released while the property MouseAction is maSelectRect. The returned coordinates are either geographical coordinates or pixel coordinates. Which kind of coordinates is returned is indicated by the parameter Layer. If Layer is zero the parameters LoX, LoY, HiX, and HiY specify the pixel coordinates, if Layer is 1 the geographic coordinates of the lower left and upper right corner of the selection rectangle are returned.

Hint: The returned coordinates are always geographic coordinates (indicated by Layer=1) unless the calibration of the map is invalid. In the case of an invalid calibration the returned coordinates are pixel coordinates (indicated by Layer=0).


Last Update: 2023-Dec-13