qgscoordinatetransform.h

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/***************************************************************************
               QgsCoordinateTransform.h  - Coordinate Transforms
                             -------------------
    begin                : Dec 2004
    copyright            : (C) 2004 Tim Sutton
    email                : tim at linfiniti.com
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
#ifndef QGSCOORDINATETRANSFORM_H
#define QGSCOORDINATETRANSFORM_H

//qt includes
#include <QObject>
#include <QThreadStorage>
#include <QReadWriteLock>

//qgis includes
#include "qgspoint.h"
#include "qgsrectangle.h"
#include "qgscsexception.h"
#include "qgscoordinatereferencesystem.h"
class QDomNode;
class QDomDocument;
class QPolygonF;

//non qt includes
#include <iostream>
#include <vector>

typedef void* projPJ;
typedef void* projCtx;
class QString;

class CORE_EXPORT QgsCoordinateTransform : public QObject
{
    Q_OBJECT
  public:
    QgsCoordinateTransform();

    QgsCoordinateTransform( const QgsCoordinateReferenceSystem& theSource,
                            const QgsCoordinateReferenceSystem& theDest );

    QgsCoordinateTransform( long theSourceSrsId, long theDestSrsId );

    QgsCoordinateTransform( const QString& theSourceWkt, const QString& theDestWkt );

    QgsCoordinateTransform( long theSourceSrid,
                            const QString& theDestWkt,
                            QgsCoordinateReferenceSystem::CrsType theSourceCRSType = QgsCoordinateReferenceSystem::PostgisCrsId );

    ~QgsCoordinateTransform();

    QgsCoordinateTransform* clone() const;

    enum TransformDirection
    {
      ForwardTransform,     
      ReverseTransform      
    };

    void setSourceCrs( const QgsCoordinateReferenceSystem& theCRS );

    void setDestCRS( const QgsCoordinateReferenceSystem& theCRS );

    const QgsCoordinateReferenceSystem& sourceCrs() const { return mSourceCRS; }

    const QgsCoordinateReferenceSystem& destCRS() const { return mDestCRS; }

    QgsPoint transform( const QgsPoint &p, TransformDirection direction = ForwardTransform ) const;

    QgsPoint transform( const double x, const double y, TransformDirection direction = ForwardTransform ) const;

    QgsRectangle transformBoundingBox( const QgsRectangle &theRect, TransformDirection direction = ForwardTransform, const bool handle180Crossover = false ) const;

    // Same as for the other transform() functions, but alters the x
    // and y variables in place. The second one works with good old-fashioned
    // C style arrays.
    void transformInPlace( double& x, double& y, double &z, TransformDirection direction = ForwardTransform ) const;

    void transformInPlace( float& x, float& y, double &z, TransformDirection direction = ForwardTransform ) const;
    void transformInPlace( float& x, float& y, float& z, TransformDirection direction = ForwardTransform ) const;
    void transformInPlace( QVector<float>& x, QVector<float>& y, QVector<float>& z,
                           TransformDirection direction = ForwardTransform ) const;

    void transformInPlace( QVector<double>& x, QVector<double>& y, QVector<double>& z,
                           TransformDirection direction = ForwardTransform ) const;

    void transformPolygon( QPolygonF& poly, TransformDirection direction = ForwardTransform ) const;

    QgsRectangle transform( const QgsRectangle &theRect, TransformDirection direction = ForwardTransform ) const;

    void transformCoords( int numPoint, double *x, double *y, double *z, TransformDirection direction = ForwardTransform ) const;

    bool isInitialised() const { return mInitialisedFlag; }

    bool isShortCircuited() const { return mShortCircuit; }

    void setDestCRSID( long theCRSID );

    static QList< QList< int > > datumTransformations( const QgsCoordinateReferenceSystem& srcCRS, const QgsCoordinateReferenceSystem& destCRS );
    static QString datumTransformString( int datumTransform );
    static bool datumTransformCrsInfo( int datumTransform, int& epsgNr, QString& srcProjection, QString& dstProjection, QString &remarks, QString &scope, bool &preferred, bool &deprecated );

    int sourceDatumTransform() const { return mSourceDatumTransform; }
    void setSourceDatumTransform( int dt ) { mSourceDatumTransform = dt; }
    int destinationDatumTransform() const { return mDestinationDatumTransform; }
    void setDestinationDatumTransform( int dt ) { mDestinationDatumTransform = dt; }

  public slots:
    void initialise();

    bool readXML( QDomNode & theNode );

    bool writeXML( QDomNode & theNode, QDomDocument & theDoc );

  signals:
    void invalidTransformInput() const;

  private:

    bool mShortCircuit;

    bool mInitialisedFlag;

    QgsCoordinateReferenceSystem mSourceCRS;

    QgsCoordinateReferenceSystem mDestCRS;

    QString mSourceProjString;
    QString mDestProjString;

    class QgsProjContextStore
    {
      public:

        QgsProjContextStore();
        ~QgsProjContextStore();

        projCtx get() { return context; }

      private:

        projCtx context;
    };

    static QThreadStorage< QgsProjContextStore* > mProjContext;
    mutable QReadWriteLock mProjLock;
    mutable QMap< uintptr_t, QPair< projPJ, projPJ > > mProjProjections;

    int mSourceDatumTransform;
    int mDestinationDatumTransform;

    void setFinder();

    static QString stripDatumTransform( const QString& proj4 );
    static void searchDatumTransform( const QString& sql, QList< int >& transforms );
    void addNullGridShifts( QString& srcProjString, QString& destProjString );

    QPair< projPJ, projPJ > threadLocalProjData() const;
    void freeProj();
};

inline std::ostream& operator << ( std::ostream& os, const QgsCoordinateTransform &r )
{
  QString mySummary( "\n%%%%%%%%%%%%%%%%%%%%%%%%\nCoordinate Transform def begins:" );
  mySummary += "\n\tInitialised? : ";
  //prevent warnings
  if ( r.isInitialised() )
  {
    //do nothing this is a dummy
  }

#if 0
  if ( r.isInitialised() )
  {
    mySummary += "Yes";
  }
  else
  {
    mySummary += "No";
  }
  mySummary += "\n\tShort Circuit?  : ";
  if ( r.isShortCircuited() )
  {
    mySummary += "Yes";
  }
  else
  {
    mySummary += "No";
  }

  mySummary += "\n\tSource Spatial Ref Sys  : ";
  if ( r.sourceCrs() )
  {
    mySummary << r.sourceCrs();
  }
  else
  {
    mySummary += "Undefined";
  }

  mySummary += "\n\tDest Spatial Ref Sys  : ";
  if ( r.destCRS() )
  {
    mySummary << r.destCRS();
  }
  else
  {
    mySummary += "Undefined";
  }
#endif

  mySummary += ( "\nCoordinate Transform def ends \n%%%%%%%%%%%%%%%%%%%%%%%%\n" );
  return os << mySummary.toLocal8Bit().data() << std::endl;
}


#endif // QGSCOORDINATETRANSFORM_H