The SDL Component Suite is an industry leading collection of components supporting scientific and engineering computing. Please visit the SDL Web site for more information....


Home GeoPack GeoMap Type Declarations and Constants TCalibData
See also: Calibration of Maps, TCalQuad, CalibModel 

TCalibData

Unit:SDL_geomap
Class: none
Declaration: 
TCalibData = record
               MapFName    : string;
               Caption     : string;
               Corners     : array[TCorners] of TCoords;
               Resolution  : double;
               NumCalLines : integer;
               CalLines    : array[1..MAXCALLINES] of TCalibLine;
               NumCalQuads : integer;
               CalQuads    : array[1..MAXCALQUADS] of TCalQuad;
               UTMZone     : integer;
               UTMSouth    : boolean;
               Ellipsoid   : TGeoEllipsoid;
             end;

The TCalibData type contains the entire information needed to calibrate a map. Please note that this data structure is prepared to hold calibration data for all available calibration models. Thus part of the structure may be empty, if only one calibration model is used. The parameter NumCalLines contains the number of calibrated graticule lines which can be accessed using the parameter CalLines (of type TCalibLine). CalLines is used for the parabolic interpolation model. The parameter NumCalQuads holds the number of calibration quadruples stored in the parameter CalQuads. The contents of CalQuads is used for the biquadratic polynomial calibration.

Corners holds the latitude and longitude of all four corners of the calibrated map. The parameter Resolution contains the resolution of the map in meters per pixel. The parameter Ellipsoid defines the ellipsoid used by some of the calibration models. For Universal Transverse Mercator (UTM) projection the UTM zone code is stored in the parameters UTMZone and UTMSouth.

The parameters MapFName and Caption contain the filename of the map image and the (invisible) caption of the map. The caption can be used to store a "nice name" along with the map data which can be presented to the user. The Caption parameter can also be accessed directly by the property Caption.

Please note that both the corner coordinates and the resolution are calculated from the calibrated graticule and cannot be set directly (cf. CalcExtentsAndResolution).

Last Update: 2023-Feb-06