AutoCAD Map 3D 2009 Geospatial Platform Reference

AutoCAD Map 3D Geospatial Platform API

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virtual MgCoordinate* MgCoordinateSystemTransform::Transform ( MgCoordinate * coordinate ) [pure virtual]

Transforms the given coordinate whose frame of reference is the source coordinate system into a coordinate whose frame of reference is the target coordinate system.

.NET Syntax

virtual MgCoordinate Transform(MgCoordinate coordinate);

Java Syntax

virtual MgCoordinate Transform(MgCoordinate coordinate);

PHP Syntax

virtual MgCoordinate Transform(MgCoordinate coordinate);

Parameters:

coordinate

(MgCoordinate) An MgCoordinate object defined in terms of the source coordinate system.

Returns:: Returns an MgCoordinate object which is the equivalent in the target coordinate system of the given coordinate.

Example (PHP) The name of $coordSys1 is "Longitude / Latitude (NAD 83)". The name of $coordSys2 is "UTM Zone 18 (NAD 83)". $csTransform12 transforms coordinates defined in terms of $coordSys1 to coordinates defined in terms of $coordSys2. $csTransform21 does the reverse.

The MgCoordinate object can contain an XY, XYM, XYZ, or XYZM coordinate. This example uses an XY coordinate.

The value of $x1Arg is -71.061342, and the value of $y1Arg is 42.355892. These values are the longitude and latitude of Boston, Massachusetts.

The output is:

xArg

x21: -71.061341999861

yArg

y21: 42.355891999573

x12

y12 : 4696809.9055963

 $csTransform12 = new MgCoordinateSystemTransform($coordSys1, $coordSys2);
 $csTransform21 = new MgCoordinateSystemTransform($coordSys2, $coordSys1);
 $coordinateArg = $geometryFactory->CreateCoordinateXY($xArg, $yArg);
 $coordinate12 = $csTransform12->Transform($coordinateArg);
 $x12 = $coordinate12->GetX();
 $y12 = $coordinate12->GetY();
 $coordinate21 = $csTransform21->Transform($coordinate12);
 $x21 = $coordinate21->GetX();
 $y21 = $coordinate21->GetY();
 echo "$xArg: $xArg; $x21: $x21n";
 echo "$yArg: $yArg; $y21: $y21n";
 echo "$x12: $x12; $y12 : $y12n";

Example (C#)

 using OSGeo.MapGuide;
 private MgCoordinateSystemTransform coordSysTransformGeogToProj;
 private MgCoordinateSystemTransform coordSysTransformProjToGeog;
 private double geogCSX = -160.101421317;
 private double geogCSY = 22.0234263273;
 private double projCSX = 386323.97632;
 private double projCSY = 2435829.67936;
 private MgCoordinate XY;
 Boolean isEquivalent;
 private double tolerance = 0.001;

 XY = coordSysTransformGeogToProj.Transform(geogCSX, geogCSY);
 the X and Y values of XY are equal to projCSX and projCSY
 isEquivalent = Math.Abs(projCSX - XY.GetX()) < tolerance && Math.Abs(projCSY - XY.GetY()) < tolerance;

 XY = coordSysTransformProjToGeog.Transform(projCSX, projCSY);
 the X and Y values of XY are equal to geogCSX and geogCSY
 isEquivalent = Math.Abs(geogCSX - XY.GetX()) < tolerance && Math.Abs(geogCSY - XY.GetY()) < tolerance;

Exceptions:

MgCoordinateSystemTransformFailedException

Implements MgTransform.

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