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Home GeoPack GeoMap Class TGeoMap Methods RemoveCalibPoint
See also: Calibration of Maps, AddCalibPoint, RestoreLastDeletedCalPoint, ClearCalibData 

RemoveCalibPoint

Unit:SDL_geomap
Class:TGeoMap
Declaration: [1] function RemoveCalibPoint (GratLineKind: TGratLineKind; LineValue: double; PixPosX, PixPosY: integer): boolean;
[2] function RemoveCalibPoint (PixPosX, PixPosY: integer): boolean;

In order to remove a calibration point from the calibration data pool, you have two possibilities: (1) you fully specify the point in the same manner as when adding a point. The function returns TRUE if the point has been removed successfully. Please note that the point to be removed is searched by comparing its parameters. Thus it is important to specify the parameters to the same precision (i.e. number of decimal places for the LineValue parameter) as when the point was entered. This version of the removal procedure is only applicable to the parabolic interpolation model. (2) The second way to use the method RemoveCalibPoint is to specify only the pixel coordinates PixPosX and PixPosY. In this case the nearest calibration point is removed.

The parameter GratLineKind defines the type of the graticule line (parallel or meridian) the point belongs to. The corresponding value of the graticule line (i.e. the latitude or the longitude) has to be passed in the parameter LineValue. PixPosX and PixPosY specify the pixel coordinates on the map image.

Hint 1: The method RemoveCalibPoint is applied only to calibration points which belong to the currently active calibration model.

Hint 2: The pixel coordinates are in the reference frame of the scanned map image, use the method MapImageToControl to transform the coordinates to the screen reference frame.

Example: This method is used in the following example program (see http://www.lohninger.com/examples.html for downloading the code): simplegeomap


Last Update: 2023-Dec-13