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Split qgscoordinatetransform_p into .h/cpp

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nyalldawson committed May 16, 2017
1 parent 59c9743 commit ae492abcf4ba007808b18ea48ddb98b2ec2f0777
Showing with 328 additions and 284 deletions.
  1. +1 −0 src/core/CMakeLists.txt
  2. +312 −0 src/core/qgscoordinatetransform_p.cpp
  3. +15 −284 src/core/qgscoordinatetransform_p.h
@@ -128,6 +128,7 @@ SET(QGIS_CORE_SRCS
qgscontexthelp.cpp
qgscoordinatereferencesystem.cpp
qgscoordinatetransform.cpp
qgscoordinatetransform_p.cpp
qgscoordinateutils.cpp
qgscredentials.cpp
qgscrscache.cpp
@@ -0,0 +1,312 @@
/***************************************************************************
qgscoordinatetransform_p.cpp
----------------------------
begin : May 2017
copyright : (C) 2017 Nyall Dawson
email : nyall dot dawson at gmail dot 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. *
* *
***************************************************************************/

#include "qgscoordinatetransform_p.h"
#include "qgslogger.h"
#include "qgsapplication.h"

extern "C"
{
#include <proj_api.h>
}
#include <sqlite3.h>

#include <QStringList>

/// @cond PRIVATE

QgsCoordinateTransformPrivate::QgsCoordinateTransformPrivate()
: mIsValid( false )
, mShortCircuit( false )
, mSourceProjection( nullptr )
, mDestinationProjection( nullptr )
, mSourceDatumTransform( -1 )
, mDestinationDatumTransform( -1 )
{
setFinder();
}

QgsCoordinateTransformPrivate::QgsCoordinateTransformPrivate( const QgsCoordinateReferenceSystem &source, const QgsCoordinateReferenceSystem &destination )
: mIsValid( false )
, mShortCircuit( false )
, mSourceCRS( source )
, mDestCRS( destination )
, mSourceProjection( nullptr )
, mDestinationProjection( nullptr )
, mSourceDatumTransform( -1 )
, mDestinationDatumTransform( -1 )
{
setFinder();
initialize();
}

QgsCoordinateTransformPrivate::QgsCoordinateTransformPrivate( const QgsCoordinateTransformPrivate &other )
: QSharedData( other )
, mIsValid( other.mIsValid )
, mShortCircuit( other.mShortCircuit )
, mSourceCRS( other.mSourceCRS )
, mDestCRS( other.mDestCRS )
, mSourceProjection( nullptr )
, mDestinationProjection( nullptr )
, mSourceDatumTransform( other.mSourceDatumTransform )
, mDestinationDatumTransform( other.mDestinationDatumTransform )
{
//must reinitialize to setup mSourceProjection and mDestinationProjection
initialize();
}

QgsCoordinateTransformPrivate::~QgsCoordinateTransformPrivate()
{
// free the proj objects
if ( mSourceProjection )
{
pj_free( mSourceProjection );
}
if ( mDestinationProjection )
{
pj_free( mDestinationProjection );
}
}

bool QgsCoordinateTransformPrivate::initialize()
{
mShortCircuit = true;
mIsValid = false;

if ( !mSourceCRS.isValid() )
{
// Pass through with no projection since we have no idea what the layer
// coordinates are and projecting them may not be appropriate
QgsDebugMsgLevel( "Source CRS is invalid!", 4 );
return false;
}

if ( !mDestCRS.isValid() )
{
//No destination projection is set so we set the default output projection to
//be the same as input proj.
mDestCRS = mSourceCRS;
QgsDebugMsgLevel( "Destination CRS is invalid!", 4 );
return false;
}

mIsValid = true;

bool useDefaultDatumTransform = ( mSourceDatumTransform == - 1 && mDestinationDatumTransform == -1 );

// init the projections (destination and source)

pj_free( mSourceProjection );
QString sourceProjString = mSourceCRS.toProj4();
if ( !useDefaultDatumTransform )
{
sourceProjString = stripDatumTransform( sourceProjString );
}
if ( mSourceDatumTransform != -1 )
{
sourceProjString += ( ' ' + datumTransformString( mSourceDatumTransform ) );
}

pj_free( mDestinationProjection );
QString destProjString = mDestCRS.toProj4();
if ( !useDefaultDatumTransform )
{
destProjString = stripDatumTransform( destProjString );
}
if ( mDestinationDatumTransform != -1 )
{
destProjString += ( ' ' + datumTransformString( mDestinationDatumTransform ) );
}

if ( !useDefaultDatumTransform )
{
addNullGridShifts( sourceProjString, destProjString );
}

mSourceProjection = pj_init_plus( sourceProjString.toUtf8() );
mDestinationProjection = pj_init_plus( destProjString.toUtf8() );

#ifdef COORDINATE_TRANSFORM_VERBOSE
QgsDebugMsg( "From proj : " + mSourceCRS.toProj4() );
QgsDebugMsg( "To proj : " + mDestCRS.toProj4() );
#endif

if ( !mDestinationProjection || !mSourceProjection )
{
mIsValid = false;
}

#ifdef COORDINATE_TRANSFORM_VERBOSE
if ( mIsValid )
{
QgsDebugMsg( "------------------------------------------------------------" );
QgsDebugMsg( "The OGR Coordinate transformation for this layer was set to" );
QgsLogger::debug<QgsCoordinateReferenceSystem>( "Input", mSourceCRS, __FILE__, __FUNCTION__, __LINE__ );
QgsLogger::debug<QgsCoordinateReferenceSystem>( "Output", mDestCRS, __FILE__, __FUNCTION__, __LINE__ );
QgsDebugMsg( "------------------------------------------------------------" );
}
else
{
QgsDebugMsg( "------------------------------------------------------------" );
QgsDebugMsg( "The OGR Coordinate transformation FAILED TO INITIALIZE!" );
QgsDebugMsg( "------------------------------------------------------------" );
}
#else
if ( !mIsValid )
{
QgsDebugMsg( "Coordinate transformation failed to initialize!" );
}
#endif

//XXX todo overload == operator for QgsCoordinateReferenceSystem
//at the moment srs.parameters contains the whole proj def...soon it won't...
//if (mSourceCRS->toProj4() == mDestCRS->toProj4())
if ( mSourceCRS == mDestCRS )
{
// If the source and destination projection are the same, set the short
// circuit flag (no transform takes place)
mShortCircuit = true;
QgsDebugMsgLevel( "Source/Dest CRS equal, shortcircuit is set.", 3 );
}
else
{
// Transform must take place
mShortCircuit = false;
QgsDebugMsgLevel( "Source/Dest CRS not equal, shortcircuit is not set.", 3 );
}
return mIsValid;
}

QString QgsCoordinateTransformPrivate::stripDatumTransform( const QString &proj4 ) const
{
QStringList parameterSplit = proj4.split( '+', QString::SkipEmptyParts );
QString currentParameter;
QString newProjString;

for ( int i = 0; i < parameterSplit.size(); ++i )
{
currentParameter = parameterSplit.at( i );
if ( !currentParameter.startsWith( QLatin1String( "towgs84" ), Qt::CaseInsensitive )
&& !currentParameter.startsWith( QLatin1String( "nadgrids" ), Qt::CaseInsensitive ) )
{
newProjString.append( '+' );
newProjString.append( currentParameter );
newProjString.append( ' ' );
}
}
return newProjString;
}

QString QgsCoordinateTransformPrivate::datumTransformString( int datumTransform )
{
QString transformString;

sqlite3 *db = nullptr;
int openResult = sqlite3_open_v2( QgsApplication::srsDatabaseFilePath().toUtf8().constData(), &db, SQLITE_OPEN_READONLY, 0 );
if ( openResult != SQLITE_OK )
{
sqlite3_close( db );
return transformString;
}

sqlite3_stmt *stmt = nullptr;
QString sql = QStringLiteral( "SELECT coord_op_method_code,p1,p2,p3,p4,p5,p6,p7 FROM tbl_datum_transform WHERE coord_op_code=%1" ).arg( datumTransform );
int prepareRes = sqlite3_prepare( db, sql.toLatin1(), sql.size(), &stmt, nullptr );
if ( prepareRes != SQLITE_OK )
{
sqlite3_finalize( stmt );
sqlite3_close( db );
return transformString;
}

if ( sqlite3_step( stmt ) == SQLITE_ROW )
{
//coord_op_methode_code
int methodCode = sqlite3_column_int( stmt, 0 );
if ( methodCode == 9615 ) //ntv2
{
transformString = "+nadgrids=" + QString( reinterpret_cast< const char * >( sqlite3_column_text( stmt, 1 ) ) );
}
else if ( methodCode == 9603 || methodCode == 9606 || methodCode == 9607 )
{
transformString += QLatin1String( "+towgs84=" );
double p1 = sqlite3_column_double( stmt, 1 );
double p2 = sqlite3_column_double( stmt, 2 );
double p3 = sqlite3_column_double( stmt, 3 );
double p4 = sqlite3_column_double( stmt, 4 );
double p5 = sqlite3_column_double( stmt, 5 );
double p6 = sqlite3_column_double( stmt, 6 );
double p7 = sqlite3_column_double( stmt, 7 );
if ( methodCode == 9603 ) //3 parameter transformation
{
transformString += QStringLiteral( "%1,%2,%3" ).arg( p1 ).arg( p2 ).arg( p3 );
}
else //7 parameter transformation
{
transformString += QStringLiteral( "%1,%2,%3,%4,%5,%6,%7" ).arg( p1 ).arg( p2 ).arg( p3 ).arg( p4 ).arg( p5 ).arg( p6 ).arg( p7 );
}
}
}

sqlite3_finalize( stmt );
sqlite3_close( db );
return transformString;
}

void QgsCoordinateTransformPrivate::addNullGridShifts( QString &srcProjString, QString &destProjString ) const
{
//if one transformation uses ntv2, the other one needs to be null grid shift
if ( mDestinationDatumTransform == -1 && srcProjString.contains( QLatin1String( "+nadgrids" ) ) ) //add null grid if source transformation is ntv2
{
destProjString += QLatin1String( " +nadgrids=@null" );
return;
}
if ( mSourceDatumTransform == -1 && destProjString.contains( QLatin1String( "+nadgrids" ) ) )
{
srcProjString += QLatin1String( " +nadgrids=@null" );
return;
}

//add null shift grid for google mercator
//(see e.g. http://trac.osgeo.org/proj/wiki/FAQ#ChangingEllipsoidWhycantIconvertfromWGS84toGoogleEarthVirtualGlobeMercator)
if ( mSourceCRS.authid().compare( QLatin1String( "EPSG:3857" ), Qt::CaseInsensitive ) == 0 && mSourceDatumTransform == -1 )
{
srcProjString += QLatin1String( " +nadgrids=@null" );
}
if ( mDestCRS.authid().compare( QLatin1String( "EPSG:3857" ), Qt::CaseInsensitive ) == 0 && mDestinationDatumTransform == -1 )
{
destProjString += QLatin1String( " +nadgrids=@null" );
}
}

void QgsCoordinateTransformPrivate::setFinder()
{
#if 0
// Attention! It should be possible to set PROJ_LIB
// but it can happen that it was previously set by installer
// (version 0.7) and the old installation was deleted

// Another problem: PROJ checks if pj_finder was set before
// PROJ_LIB environment variable. pj_finder is probably set in
// GRASS gproj library when plugin is loaded, consequently
// PROJ_LIB is ignored

pj_set_finder( finder );
#endif
}

///@endcond

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