Further tweaks and fixes for transformation selection dialog

python/core/auto_generated/qgsdatumtransform.sip.in

@@ -87,6 +87,8 @@ and ``destinationTransformId`` transforms.
       QString scope;
 
       QString remarks;
+
+      QString areaOfUse;
     };
 
     struct TransformDetails
@@ -95,8 +97,14 @@ and ``destinationTransformId`` transforms.
       QString name;
       double accuracy;
 
+      QString scope;
+
+      QString remarks;
+
       bool isAvailable;
 
+      QString areaOfUse;
+
       QList< QgsDatumTransform::GridDetails > grids;
 
       QList< QgsDatumTransform::SingleOperationDetails > operationDetails;

src/core/qgsdatumtransform.cpp

@@ -323,6 +323,17 @@ QgsDatumTransform::TransformDetails QgsDatumTransform::transformDetailsFromPj( P
   details.accuracy = proj_coordoperation_get_accuracy( pjContext, op );
   details.isAvailable = proj_coordoperation_is_instantiable( pjContext, op );
 
+  const char *areaOfUseName = nullptr;
+  if ( proj_get_area_of_use( pjContext, op, nullptr, nullptr, nullptr, nullptr, &areaOfUseName ) )
+  {
+    details.areaOfUse = QString( areaOfUseName );
+  }
+
+#if PROJ_VERSION_MAJOR > 6 or PROJ_VERSION_MINOR >= 2
+  details.remarks = QString( proj_get_remarks( op ) );
+  details.scope = QString( proj_get_scope( op ) );
+#endif
+
   for ( int j = 0; j < proj_coordoperation_get_grid_used_count( pjContext, op ); ++j )
   {
     const char *shortName = nullptr;
@@ -354,6 +365,12 @@ QgsDatumTransform::TransformDetails QgsDatumTransform::transformDetailsFromPj( P
       SingleOperationDetails singleOpDetails;
       singleOpDetails.remarks = QString( proj_get_remarks( step.get() ) );
       singleOpDetails.scope = QString( proj_get_scope( step.get() ) );
+
+      const char *areaOfUseName = nullptr;
+      if ( proj_get_area_of_use( pjContext, step.get(), nullptr, nullptr, nullptr, nullptr, &areaOfUseName ) )
+      {
+        singleOpDetails.areaOfUse = QString( areaOfUseName );
+      }
       details.operationDetails.append( singleOpDetails );
     }
   }

src/core/qgsdatumtransform.h

@@ -160,6 +160,9 @@ class CORE_EXPORT QgsDatumTransform
 
       //! Remarks for operation, from EPSG registry database
       QString remarks;
+
+      //! Area of use, from EPSG registry database
+      QString areaOfUse;
     };
 
     /**
@@ -177,6 +180,22 @@ class CORE_EXPORT QgsDatumTransform
       //! Transformation accuracy (in meters)
       double accuracy = 0;
 
+      /**
+       * Scope of operation, from EPSG registry database.
+       *
+       * This is only available for single step coordinate operations. For multi-step operations, check
+       * \a operationDetails instead.
+       */
+      QString scope;
+
+      /**
+      * Remarks for operation, from EPSG registry database.
+      *
+      * This is only available for single step coordinate operations. For multi-step operations, check
+      * \a operationDetails instead.
+      */
+      QString remarks;
+
       /**
        * TRUE if operation is available.
        *
@@ -185,6 +204,14 @@ class CORE_EXPORT QgsDatumTransform
        */
       bool isAvailable = false;
 
+      /**
+       * Area of use string.
+       *
+       * This is only available for single step coordinate operations. For multi-step operations, check
+       * \a operationDetails instead.
+       */
+      QString areaOfUse;
+
       /**
        * Contains a list of transform grids used by the operation.
        */

src/core/qgsprojutils.cpp

@@ -204,8 +204,7 @@ QList<QgsDatumTransform::GridDetails> QgsProjUtils::gridsUsed( const QString &pr
     const QString gridName = match.captured( 1 );
     QgsDatumTransform::GridDetails grid;
     grid.shortName = gridName;
-#if PROJ_VERSION_MAJOR >= 6
-#if PROJ_VERSION_MINOR >= 2
+#if PROJ_VERSION_MAJOR > 6 or PROJ_VERSION_MINOR >= 2
     const char *fullName = nullptr;
     const char *packageName = nullptr;
     const char *url = nullptr;
@@ -219,7 +218,6 @@ QList<QgsDatumTransform::GridDetails> QgsProjUtils::gridsUsed( const QString &pr
     grid.directDownload = directDownload;
     grid.openLicense = openLicense;
     grid.isAvailable = available;
-#endif
 #endif
     grids.append( grid );
   }

src/gui/qgsdatumtransformdialog.cpp

@@ -82,6 +82,9 @@ QgsDatumTransformDialog::QgsDatumTransformDialog( const QgsCoordinateReferenceSy
 
   QgsGui::enableAutoGeometryRestore( this );
 
+  mLabelSrcDescription->setTextInteractionFlags( Qt::TextBrowserInteraction );
+  mLabelSrcDescription->setOpenExternalLinks( true );
+
   if ( !showMakeDefault )
     mMakeDefaultCheckBox->setVisible( false );
 
@@ -92,10 +95,15 @@ QgsDatumTransformDialog::QgsDatumTransformDialog( const QgsCoordinateReferenceSy
     setWindowFlags( windowFlags() & ~Qt::WindowCloseButtonHint );
   }
 
+#if PROJ_VERSION_MAJOR>=6
+  mDatumTransformTableWidget->setColumnCount( 3 );
+#else
   mDatumTransformTableWidget->setColumnCount( 2 );
+#endif
+
   QStringList headers;
 #if PROJ_VERSION_MAJOR>=6
-  headers << tr( "Transformation" ) << tr( "Accuracy (meters)" ) ;
+  headers << tr( "Transformation" ) << tr( "Accuracy (meters)" ) << tr( "Area of Use" );
 #else
   headers << tr( "Source Transform" ) << tr( "Destination Transform" ) ;
 #endif
@@ -159,10 +167,9 @@ void QgsDatumTransformDialog::load( QPair<int, int> selectedDatumTransforms, con
   Q_UNUSED( selectedDatumTransforms )
   for ( const QgsDatumTransform::TransformDetails &transform : qgis::as_const( mDatumTransforms ) )
   {
-    bool itemDisabled = !transform.isAvailable;
-
     std::unique_ptr< QTableWidgetItem > item = qgis::make_unique< QTableWidgetItem >();
     item->setData( ProjRole, transform.proj );
+    item->setData( AvailableRole, transform.isAvailable );
     item->setFlags( item->flags() & ~Qt::ItemIsEditable );
 
     item->setText( transform.name );
@@ -175,12 +182,55 @@ void QgsDatumTransformDialog::load( QPair<int, int> selectedDatumTransforms, con
       item->setForeground( QBrush( QColor( 0, 120, 0 ) ) );
     }
 
+    if ( !transform.isAvailable )
+    {
+      item->setForeground( QBrush( palette().color( QPalette::Disabled, QPalette::Text ) ) );
+    }
+
     if ( preferredInitialRow < 0 && transform.isAvailable )
     {
       // try to select a "preferred" entry by default
       preferredInitialRow = row;
     }
 
+    QString missingMessage;
+    if ( !transform.isAvailable )
+    {
+      QStringList gridMessages;
+      for ( const QgsDatumTransform::GridDetails &grid : transform.grids )
+      {
+        if ( !grid.isAvailable )
+        {
+          QString m = tr( "This transformation requires the grid file “%1”, which is not available for use on the system." ).arg( grid.shortName );
+          if ( !grid.url.isEmpty() )
+          {
+            if ( !grid.packageName.isEmpty() )
+            {
+              m += ' ' +  tr( "This grid is part of the <i>%1</i> package, available for download from <a href=\"%2\">%2</a>." ).arg( grid.packageName, grid.url );
+            }
+            else
+            {
+              m += ' ' + tr( "This grid is available for download from <a href=\"%1\">%1</a>." ).arg( grid.url );
+            }
+          }
+          gridMessages << m;
+        }
+      }
+
+      if ( gridMessages.count() > 1 )
+      {
+        for ( int k = 0; k < gridMessages.count(); ++k )
+          gridMessages[k] = QStringLiteral( "<li>%1</li>" ).arg( gridMessages.at( k ) );
+
+        missingMessage = QStringLiteral( "<ul>%1</ul" ).arg( gridMessages.join( QString() ) );
+      }
+      else if ( !gridMessages.empty() )
+      {
+        missingMessage = gridMessages.constFirst();
+      }
+    }
+
+    QStringList areasOfUse;
 
 #if PROJ_VERSION_MAJOR > 6 or PROJ_VERSION_MINOR >= 2
     QStringList opText;
@@ -197,48 +247,89 @@ void QgsDatumTransformDialog::load( QPair<int, int> selectedDatumTransforms, con
           text += QStringLiteral( "<br>" );
         text += QStringLiteral( "<b>%1</b>: %2" ).arg( tr( "Remarks" ), singleOpDetails.remarks );
       }
+      if ( !singleOpDetails.areaOfUse.isEmpty() )
+      {
+        if ( !areasOfUse.contains( singleOpDetails.areaOfUse ) )
+          areasOfUse << singleOpDetails.areaOfUse;
+      }
 
       if ( !text.isEmpty() )
       {
         opText.append( text );
       }
     }
 
+    QString text;
+    if ( !transform.scope.isEmpty() )
+    {
+      text += QStringLiteral( "<b>%1</b>: %2" ).arg( tr( "Scope" ), transform.scope );
+    }
+    if ( !transform.remarks.isEmpty() )
+    {
+      if ( !text.isEmpty() )
+        text += QStringLiteral( "<br>" );
+      text += QStringLiteral( "<b>%1</b>: %2" ).arg( tr( "Remarks" ), transform.remarks );
+    }
+    if ( !text.isEmpty() )
+    {
+      opText.append( text );
+    }
+
     if ( opText.count() > 1 )
     {
       for ( int k = 0; k < opText.count(); ++k )
         opText[k] = QStringLiteral( "<li>%1</li>" ).arg( opText.at( k ) );
     }
+#endif
+
+    if ( !transform.areaOfUse.isEmpty() && !areasOfUse.contains( transform.areaOfUse ) )
+      areasOfUse << transform.areaOfUse;
 
+#if PROJ_VERSION_MAJOR > 6 or PROJ_VERSION_MINOR >= 2
     const QColor disabled = palette().color( QPalette::Disabled, QPalette::Text );
     const QColor active = palette().color( QPalette::Active, QPalette::Text );
 
     const QColor codeColor( static_cast< int >( active.red() * 0.6 + disabled.red() * 0.4 ),
                             static_cast< int >( active.green() * 0.6 + disabled.green() * 0.4 ),
                             static_cast< int >( active.blue() * 0.6 + disabled.blue() * 0.4 ) );
     const QString toolTipString = QStringLiteral( "<b>%1</b>" ).arg( transform.name )
-                                  + ( !opText.empty() ? ( opText.count() == 1 ? QStringLiteral( "<p>%1</p>" ).arg( opText.at( 0 ) ) : QStringLiteral( "<ul>%1</ul>" ).arg( opText.join( QString() ) ) ) : QString() ) +
-                                  QStringLiteral( "<p><code style=\"color: %1\">%2</code></p>" ).arg( codeColor.name(), transform.proj );
+                                  + ( !opText.empty() ? ( opText.count() == 1 ? QStringLiteral( "<p>%1</p>" ).arg( opText.at( 0 ) ) : QStringLiteral( "<ul>%1</ul>" ).arg( opText.join( QString() ) ) ) : QString() )
+                                  + ( !areasOfUse.empty() ? QStringLiteral( "<p><b>%1</b>: %2</p>" ).arg( tr( "Area of use" ), areasOfUse.join( QStringLiteral( ", " ) ) ) : QString() )
+                                  + ( !missingMessage.isEmpty() ? QStringLiteral( "<p><b style=\"color: red\">%1</b></p>" ).arg( missingMessage ) : QString() )
+                                  + QStringLiteral( "<p><code style=\"color: %1\">%2</code></p>" ).arg( codeColor.name(), transform.proj );
 #else
-    const QString toolTipString = QStringLiteral( "<b>%1</b><p><code>%2</code></p>" ).arg( transform.name, transform.proj );
+    const QString toolTipString = QStringLiteral( "<b>%1</b>%2%3<p><code>%4</code></p>" ).arg( transform.name,
+                                  ( !transform.areaOfUse.isEmpty() ? QStringLiteral( "<p><b>%1</b>: %2</p>" ).arg( tr( "Area of use" ), transform.areaOfUse ) : QString() ),
+                                  ( !missingMessage.isEmpty() ? QStringLiteral( "<p><b style=\"color: red\">%1</b></p>" ).arg( missingMessage ) : QString() ),
+                                  transform.proj );
 #endif
     item->setToolTip( toolTipString );
-    if ( itemDisabled )
-    {
-      item->setFlags( Qt::NoItemFlags );
-    }
     mDatumTransformTableWidget->setRowCount( row + 1 );
     mDatumTransformTableWidget->setItem( row, 0, item.release() );
 
     item = qgis::make_unique< QTableWidgetItem >();
     item->setFlags( item->flags() & ~Qt::ItemIsEditable );
     item->setText( transform.accuracy >= 0 ? QString::number( transform.accuracy ) : tr( "Unknown" ) );
-    if ( itemDisabled )
+    item->setToolTip( toolTipString );
+    if ( !transform.isAvailable )
     {
-      item->setFlags( Qt::NoItemFlags );
+      item->setForeground( QBrush( palette().color( QPalette::Disabled, QPalette::Text ) ) );
     }
     mDatumTransformTableWidget->setItem( row, 1, item.release() );
 
+#if PROJ_VERSION_MAJOR>=6
+    // area of use column
+    item = qgis::make_unique< QTableWidgetItem >();
+    item->setFlags( item->flags() & ~Qt::ItemIsEditable );
+    item->setText( areasOfUse.join( QStringLiteral( ", " ) ) );
+    item->setToolTip( toolTipString );
+    if ( !transform.isAvailable )
+    {
+      item->setForeground( QBrush( palette().color( QPalette::Disabled, QPalette::Text ) ) );
+    }
+    mDatumTransformTableWidget->setItem( row, 2, item.release() );
+#endif
+
     if ( transform.proj == selectedProj )
     {
       mDatumTransformTableWidget->selectRow( row );
@@ -356,7 +447,12 @@ void QgsDatumTransformDialog::load( QPair<int, int> selectedDatumTransforms, con
 void QgsDatumTransformDialog::setOKButtonEnabled()
 {
   int row = mDatumTransformTableWidget->currentRow();
+#if PROJ_VERSION_MAJOR>=6
+  mButtonBox->button( QDialogButtonBox::Ok )->setEnabled( mSourceCrs.isValid() && mDestinationCrs.isValid()
+      && mDatumTransformTableWidget->item( row, 0 ) && mDatumTransformTableWidget->item( row, 0 )->data( AvailableRole ).toBool() );
+#else
   mButtonBox->button( QDialogButtonBox::Ok )->setEnabled( mSourceCrs.isValid() && mDestinationCrs.isValid() && row >= 0 );
+#endif
 }
 
 QgsDatumTransformDialog::~QgsDatumTransformDialog()

src/gui/qgsdatumtransformdialog.h

@@ -108,6 +108,7 @@ class GUI_EXPORT QgsDatumTransformDialog : public QDialog, private Ui::QgsDatumT
     {
       TransformIdRole = Qt::UserRole + 1,
       ProjRole,
+      AvailableRole,
     };
 
     bool gridShiftTransformation( const QString &itemText ) const;

src/gui/qgsprojectionselectiontreewidget.cpp

@@ -95,8 +95,15 @@ QgsProjectionSelectionTreeWidget::QgsProjectionSelectionTreeWidget( QWidget *par
   mRecentProjections = QgsCoordinateReferenceSystem::recentProjections();
 
   mCheckBoxNoProjection->setHidden( true );
+  mCheckBoxNoProjection->setEnabled( false );
   connect( mCheckBoxNoProjection, &QCheckBox::toggled, this, &QgsProjectionSelectionTreeWidget::crsSelected );
-  connect( mCheckBoxNoProjection, &QCheckBox::toggled, mFrameProjections, &QFrame::setDisabled );
+  connect( mCheckBoxNoProjection, &QCheckBox::toggled, this, [ = ]( bool checked )
+  {
+    if ( mCheckBoxNoProjection->isEnabled() )
+    {
+      mFrameProjections->setDisabled( checked );
+    }
+  } );
 }
 
 QgsProjectionSelectionTreeWidget::~QgsProjectionSelectionTreeWidget()
@@ -472,7 +479,7 @@ QString QgsProjectionSelectionTreeWidget::getSelectedExpression( const QString &
 
 QgsCoordinateReferenceSystem QgsProjectionSelectionTreeWidget::crs() const
 {
-  if ( mCheckBoxNoProjection->isChecked() )
+  if ( mCheckBoxNoProjection->isEnabled() && mCheckBoxNoProjection->isChecked() )
     return QgsCoordinateReferenceSystem();
 
   int srid = getSelectedExpression( QStringLiteral( "srs_id" ) ).toLong();
@@ -484,7 +491,12 @@ QgsCoordinateReferenceSystem QgsProjectionSelectionTreeWidget::crs() const
 
 void QgsProjectionSelectionTreeWidget::setShowNoProjection( bool show )
 {
-  mCheckBoxNoProjection->setHidden( !show );
+  mCheckBoxNoProjection->setVisible( show );
+  mCheckBoxNoProjection->setEnabled( show );
+  if ( show )
+  {
+    mFrameProjections->setDisabled( mCheckBoxNoProjection->isChecked() );
+  }
 }
 
 void QgsProjectionSelectionTreeWidget::setShowBoundsMap( bool show )