[mapguide-trac] #143: Transforming Coordinates from MgPoint

[MapGuide Open Source]

#143: Transforming Coordinates from MgPoint
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   Reporter:  JimO     |       Owner:     
       Type:  defect   |      Status:  new
   Priority:  medium   |   Milestone:     
  Component:  General  |     Version:     
   Severity:  major    |    Keywords:     
External_id:           |  
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 I am able to transform coordinates on the fly from a FeatureReader,
 but not from an MgPoint. The MgPoint->Transform() returns the coordinate
 as rads and must be converted like this:

 $x = $x / M_PI * 180.0;// M_PI is the PHP constant for pi
 $y = $y / M_PI * 180.0;

 This transform into rads works from BC Albers to LL84, but does not work
 at all the other way.

 The featurereader code that works goes:

 while ($featureReader->ReadNext())
 {
     // MgByteReader *  GetGeometry (CREFSTRING propertyName)=0
     // Gets the Geometry for the specified property.
     $byteReader = $featureReader->GetGeometry('GEOMETRY');
     // MgGeometry *  Read (MgByteReader *agf)
     // Translates an MgByteReader object into an MgGeometry object.
     $geometry = $agfReaderWriter->Read($byteReader);
     $geometry = $geometry->Transform($transform);

 The MgPoint code that works only one way and returns a coordinate as rads
 goes:

 // MgCoordinate *  CreateCoordinateXY (double x, double y)
 // Creates an MgCoordinate object with Dimension = XY
 $coord = $geometryFactory->CreateCoordinateXY((double) $_REQUEST['x'],
 (double) $_REQUEST['y']);
 // MgPoint *  CreatePoint (MgCoordinate *coordinate)
 // Creates a point from a coordinate.
 $point = $geometryFactory->CreatePoint($coord);
 // MgPoint is a subclass of MgGeometry
 $point = $point->Transform($transform);

-- 
Ticket URL: <http://trac.osgeo.org/mapguide/ticket/143>
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