Example #1
0
void TestQgsDistanceArea::unit_conversions()
{
    // Do some very simple test of conversion and units
    QgsDistanceArea myDa;
    myDa.setEllipsoidalMode( false );

    double inputValue;
    QGis::UnitType inputUnit;
    QGis::UnitType outputUnit;

    inputValue = 10000.0;
    inputUnit = QGis::Meters;
    outputUnit = QGis::Feet;
    //outputUnit = QGis::Meters;

    // First, convert from sq.meter to sq.feet
    Q_NOWARN_DEPRECATED_PUSH
    myDa.convertMeasurement( inputValue, inputUnit, outputUnit, true );
    Q_NOWARN_DEPRECATED_POP
    QVERIFY( qAbs( inputValue - 107639.1041671 ) <= 0.0000001 );

    // The print a text unit. This is i18n, so we should ignore the unit
    // and use the locale settings for separation of digits.
    QString myTxt = QgsDistanceArea::textUnit( inputValue, 7, inputUnit, true, false );
    QString expectedTxt = QLocale::system().toString( 2.4710538146717, 'g', 1 + 7 );
    QVERIFY( myTxt.startsWith( expectedTxt ) ); // Ignore units for now.
}
void QgsMapToolIdentify::convertMeasurement( QgsDistanceArea &calc, double &measure, QGis::UnitType &u, bool isArea )
{
  // Helper for converting between meters and feet
  // The parameter &u is out only...

  // Get the canvas units
  QGis::UnitType myUnits = mCanvas->mapUnits();

  // Get the units for display
  QSettings settings;
  QGis::UnitType displayUnits = QGis::fromLiteral( settings.value( "/qgis/measure/displayunits", QGis::toLiteral( QGis::Meters ) ).toString() );

  calc.convertMeasurement( measure, myUnits, displayUnits, isArea );
  u = myUnits;
}
void QgsMapToolViewshed::drawFinished()
{
  QString layerid = QgsProject::instance()->readEntry( "Heightmap", "layer" );
  QgsMapLayer* layer = QgsMapLayerRegistry::instance()->mapLayer( layerid );
  if ( !layer || layer->type() != QgsMapLayer::RasterLayer )
  {
    QgisApp::instance()->messageBar()->pushMessage( tr( "No heightmap is defined in the project." ), tr( "Right-click a raster layer in the layer tree and select it to be used as heightmap." ), QgsMessageBar::INFO, 10 );
    reset();
    return;
  }

  QgsCoordinateReferenceSystem canvasCrs = canvas()->mapSettings().destinationCrs();
  double curRadius;
  QgsPoint center;
  double trash;
  getPart( 0, center, curRadius, trash, trash );

  QGis::UnitType measureUnit = canvasCrs.mapUnits();
  QgsDistanceArea().convertMeasurement( curRadius, measureUnit, QGis::Meters, false );

  QgsViewshedDialog viewshedDialog( curRadius );
  connect( &viewshedDialog, SIGNAL( radiusChanged( double ) ), this, SLOT( adjustRadius( double ) ) );
  if ( viewshedDialog.exec() == QDialog::Rejected )
  {
    reset();
    return;
  }

  QString outputFileName = QString( "viewshed_%1,%2.tif" ).arg( center.x() ).arg( center.y() );
  QString outputFile = QgsTemporaryFile::createNewFile( outputFileName );

  QVector<QgsPoint> filterRegion;
  QgsPolygon poly = QgsGeometry( getRubberBand()->geometry()->clone() ).asPolygon();
  if ( !poly.isEmpty() )
  {
    filterRegion = poly.front();
  }
  getPart( 0, center, curRadius, trash, trash );

  if ( mCanvas->mapSettings().mapUnits() == QGis::Degrees )
  {
    // Need to compute radius in meters
    QgsDistanceArea da;
    da.setSourceCrs( mCanvas->mapSettings().destinationCrs() );
    da.setEllipsoid( QgsProject::instance()->readEntry( "Measure", "/Ellipsoid", GEO_NONE ) );
    da.setEllipsoidalMode( mCanvas->mapSettings().hasCrsTransformEnabled() );
    curRadius = da.measureLine( center, QgsPoint( center.x() + curRadius, center.y() ) );
    QGis::UnitType measureUnits = mCanvas->mapSettings().mapUnits();
    da.convertMeasurement( curRadius, measureUnits, QGis::Meters, false );
  }

  double heightConv = QGis::fromUnitToUnitFactor( QgsCoordinateFormat::instance()->getHeightDisplayUnit(), QGis::Meters );

  QProgressDialog p( tr( "Calculating viewshed..." ), tr( "Abort" ), 0, 0 );
  p.setWindowTitle( tr( "Viewshed" ) );
  p.setWindowModality( Qt::ApplicationModal );
  bool displayVisible = viewshedDialog.getDisplayMode() == QgsViewshedDialog::DisplayVisibleArea;
  int accuracyFactor = viewshedDialog.getAccuracyFactor();
  QApplication::setOverrideCursor( Qt::WaitCursor );
  bool success = QgsViewshed::computeViewshed( layer->source(), outputFile, "GTiff", center, canvasCrs, viewshedDialog.getObserverHeight() * heightConv, viewshedDialog.getTargetHeight() * heightConv, viewshedDialog.getHeightRelativeToGround(), curRadius, QGis::Meters, filterRegion, displayVisible, accuracyFactor, &p );
  QApplication::restoreOverrideCursor();
  if ( success )
  {
    QgsRasterLayer* layer = new QgsRasterLayer( outputFile, tr( "Viewshed [%1]" ).arg( center.toString() ) );
    QgsColorRampShader* rampShader = new QgsColorRampShader();
    if ( displayVisible )
    {
      QList<QgsColorRampShader::ColorRampItem> colorRampItems = QList<QgsColorRampShader::ColorRampItem>()
          << QgsColorRampShader::ColorRampItem( 0, QColor( 0, 0, 0, 0 ), "" )
          << QgsColorRampShader::ColorRampItem( 255, QColor( 0, 255, 0 ), tr( "Visible" ) );
      rampShader->setColorRampItemList( colorRampItems );
    }
    else
    {
      QList<QgsColorRampShader::ColorRampItem> colorRampItems = QList<QgsColorRampShader::ColorRampItem>()
          << QgsColorRampShader::ColorRampItem( 0, QColor( 0, 0, 0, 0 ), "" )
          << QgsColorRampShader::ColorRampItem( 0, QColor( 255, 0, 0 ), tr( "Invisible" ) );
      rampShader->setColorRampItemList( colorRampItems );
    }
    QgsRasterShader* shader = new QgsRasterShader();
    shader->setRasterShaderFunction( rampShader );
    QgsSingleBandPseudoColorRenderer* renderer = new QgsSingleBandPseudoColorRenderer( 0, 1, shader );
    layer->setRenderer( renderer );
    QgsMapLayerRegistry::instance()->addMapLayer( layer );
    QgsPinAnnotationItem* pin = new QgsPinAnnotationItem( canvas() );
    pin->setMapPosition( center, canvasCrs );
    pin->setItemFlags( pin->itemFlags() | QgsAnnotationItem::ItemMapPositionLocked );
    QgisApp::instance()->itemCouplingManager()->addCoupling( layer, pin );
  }
  else
  {
    QMessageBox::critical( 0, tr( "Error" ), tr( "Failed to compute viewshed." ) );
  }
  reset();
}