virtual MgEnvelope* MgCoordinateSystemTransform::Transform

(

MgEnvelope *

envelope

)

[pure virtual]

Transforms an MgEnvelope instance for the source coordinate system into an MgEnvelope instance for target coordinate system.

.NET Syntax

virtual MgEnvelope Transform(MgEnvelope envelope);

Java Syntax

virtual MgEnvelope Transform(MgEnvelope envelope);

PHP Syntax

virtual MgEnvelope Transform(MgEnvelope envelope);

Parameters:

envelope

(MgEnvelope) An MgEnvelope object obtained from the MgCoordinateSystemMeasure for the source coordinate system.

Returns:

Returns an MgEnvelope object for the target coordinate system..

Example (PHP)
The result of executing this code is that $env1 is the same as $env21 and $env2 is the same as $env12.

 $coordSys1 = $coordSysFactory->Create($wkt1);
 $coordSys2 = $coordSysFactory->Create($wkt2);
 $csTransform12 = new MgCoordinateSystemTransform($coordSys1, $coordSys2);
 $csTransform21 = new MgCoordinateSystemTransform($coordSys2, $coordSys1);
 $coordSysMeasure1 = new MgCoordinateSystemMeasure($coordSys1);
 $coordSysMeasure2 = new MgCoordinateSystemMeasure($coordSys2);
 $env1 = $coordSysMeasure1->GetEnvelope();
 $env2 = $coordSysMeasure2->GetEnvelope();
 $env12 = $csTransform12->Transform($env1);
 $env21 = $csTransform21->Transform($env2);

Example (C#)
This code creates a geography coordinate system envelope that is approximately 30 km on the diagonal and transforms that envelope into its equivalent in a projected coordinate system.

 using OSGeo.MapGuide;
 private MgCoordinateSystemTransform coordSysTransformGeogToProj;
 private MgCoordinateSystemTransform coordSysTransformProjToGeog;
 private double geogCSX = -160.101421317;
 private double geogCSY = 22.0234263273;
 private MgEnvelope geogCSEnv;
 private MgEnvelope projCSEnv;
 private double urX = geogCSX + 0.2;
 private double urY = geogCSY + 0.2;
 double expectedProjLLX = 386323.976322775;
 double expectedProjLLY = 2435694.36972722;
 double expectedProjURX = 407098.230068439;
 double expectedProjURY = 2457970.15998103;
 double tolerance = 0.001;
 Boolean lowerLeftIsEquivalent;
 Boolean upperRightIsEquivalent;

 geogCSEnv = new MgEnvelope(geogCSX, geogCSY, urX, urY);
 projCSEnv = coordSysTransformGeogToProj.Transform(geogCSEnv);
 lowerLeftIsEquivalent = Math.Abs(expectedProjLLX - projCSEnv.GetLowerLeftCoordinate().GetX()) < tolerance && Math.Abs(expectedProjLLY - projCSEnv.GetLowerLeftCoordinate().GetY()) < tolerance;
 upperRightIsEquivalent = Math.Abs(expectedProjURX - projCSEnv.GetUpperRightCoordinate().GetX()) < tolerance && Math.Abs(expectedProjURY - projCSEnv.GetUpperRightCoordinate().GetY()) < tolerance;

Exceptions:

MgCoordinateSystemTransformFailedException

Implements MgTransform.