diff --git a/src/backend/worksheet/plots/cartesian/CartesianPlot.cpp b/src/backend/worksheet/plots/cartesian/CartesianPlot.cpp
index 428495d25..4c83c6fa4 100644
--- a/src/backend/worksheet/plots/cartesian/CartesianPlot.cpp
+++ b/src/backend/worksheet/plots/cartesian/CartesianPlot.cpp
@@ -1,2965 +1,2971 @@
 /***************************************************************************
     File                 : CartesianPlot.cpp
     Project              : LabPlot
     Description          : Cartesian plot
     --------------------------------------------------------------------
     Copyright            : (C) 2011-2017 by Alexander Semke (alexander.semke@web.de)
     Copyright            : (C) 2016-2017 by Stefan Gerlach (stefan.gerlach@uni.kn)
 
  ***************************************************************************/
 
 /***************************************************************************
  *                                                                         *
  *  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.                                    *
  *                                                                         *
  *  This program is distributed in the hope that it will be useful,        *
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of         *
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
  *  GNU General Public License for more details.                           *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program; if not, write to the Free Software           *
  *   Foundation, Inc., 51 Franklin Street, Fifth Floor,                    *
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
 
 #include "CartesianPlot.h"
 #include "CartesianPlotPrivate.h"
 #include "Axis.h"
 #include "XYCurve.h"
 #include "Histogram.h"
 #include "XYEquationCurve.h"
 #include "XYDataReductionCurve.h"
 #include "XYDifferentiationCurve.h"
 #include "XYIntegrationCurve.h"
 #include "XYInterpolationCurve.h"
 #include "XYSmoothCurve.h"
 #include "XYFitCurve.h"
 #include "XYFourierFilterCurve.h"
 #include "XYFourierTransformCurve.h"
 #include "backend/core/Project.h"
 #include "backend/spreadsheet/Spreadsheet.h"
 #include "backend/worksheet/plots/cartesian/CartesianPlotLegend.h"
 #include "backend/worksheet/plots/cartesian/CustomPoint.h"
 #include "backend/worksheet/plots/PlotArea.h"
 #include "backend/worksheet/plots/AbstractPlotPrivate.h"
 #include "backend/worksheet/Worksheet.h"
 #include "backend/worksheet/plots/cartesian/Axis.h"
 #include "backend/worksheet/TextLabel.h"
 #include "backend/lib/XmlStreamReader.h"
 #include "backend/lib/commandtemplates.h"
 #include "backend/lib/macros.h"
 #include "backend/lib/trace.h"
 #include "kdefrontend/spreadsheet/PlotDataDialog.h" //for PlotDataDialog::AnalysisAction. TODO: find a better place for this enum.
 #include "kdefrontend/ThemeHandler.h"
 #include "kdefrontend/widgets/ThemesWidget.h"
 
 #include <QDir>
 #include <QDropEvent>
 #include <QIcon>
 #include <QMenu>
 #include <QMimeData>
 #include <QPainter>
 #include <QToolBar>
 #include <QWidgetAction>
 
 #include <KConfigGroup>
 #include <KLocale>
 
 /**
  * \class CartesianPlot
  * \brief A xy-plot.
  *
  *
  */
 CartesianPlot::CartesianPlot(const QString &name):AbstractPlot(name, new CartesianPlotPrivate(this)),
 	m_legend(0), m_zoomFactor(1.2), m_menusInitialized(false),
 	addNewMenu(nullptr), zoomMenu(nullptr), dataAnalysisMenu(nullptr), themeMenu(nullptr) {
 	init();
 }
 
 CartesianPlot::CartesianPlot(const QString &name, CartesianPlotPrivate *dd):AbstractPlot(name, dd),
 	m_legend(0), m_zoomFactor(1.2),
 	addNewMenu(nullptr), zoomMenu(nullptr), dataAnalysisMenu(nullptr), themeMenu(nullptr) {
 	init();
 }
 
 CartesianPlot::~CartesianPlot() {
 	if (m_menusInitialized) {
 		delete addNewMenu;
 		delete zoomMenu;
 		delete themeMenu;
 	}
 
 	delete m_coordinateSystem;
 
 	//don't need to delete objects added with addChild()
 
 	//no need to delete the d-pointer here - it inherits from QGraphicsItem
 	//and is deleted during the cleanup in QGraphicsScene
 }
 
 /*!
 	initializes all member variables of \c CartesianPlot
 */
 void CartesianPlot::init() {
 	Q_D(CartesianPlot);
 
 	d->cSystem = new CartesianCoordinateSystem(this);
 	m_coordinateSystem = d->cSystem;
 
 	d->rangeType = CartesianPlot::RangeFree;
 	d->rangeLastValues = 1000;
 	d->rangeFirstValues = 1000;
 	d->autoScaleX = true;
 	d->autoScaleY = true;
 	d->xScale = ScaleLinear;
 	d->yScale = ScaleLinear;
 	d->xRangeBreakingEnabled = false;
 	d->yRangeBreakingEnabled = false;
 
 	//the following factor determines the size of the offset between the min/max points of the curves
 	//and the coordinate system ranges, when doing auto scaling
 	//Factor 0 corresponds to the exact match - min/max values of the curves correspond to the start/end values of the ranges.
 	//TODO: make this factor optional.
 	//Provide in the UI the possibility to choose between "exact" or 0% offset, 2%, 5% and 10% for the auto fit option
 	d->autoScaleOffsetFactor = 0.0f;
 
 	m_plotArea = new PlotArea(name() + " plot area");
 	addChildFast(m_plotArea);
 
 	//offset between the plot area and the area defining the coordinate system, in scene units.
 	d->horizontalPadding = Worksheet::convertToSceneUnits(1.5, Worksheet::Centimeter);
 	d->verticalPadding = Worksheet::convertToSceneUnits(1.5, Worksheet::Centimeter);
 
 	connect(this, SIGNAL(aspectAdded(const AbstractAspect*)), this, SLOT(childAdded(const AbstractAspect*)));
 	connect(this, SIGNAL(aspectRemoved(const AbstractAspect*,const AbstractAspect*,const AbstractAspect*)),
 	        this, SLOT(childRemoved(const AbstractAspect*,const AbstractAspect*,const AbstractAspect*)));
 
 	graphicsItem()->setFlag(QGraphicsItem::ItemIsMovable, true);
 	graphicsItem()->setFlag(QGraphicsItem::ItemClipsChildrenToShape, true);
 	graphicsItem()->setFlag(QGraphicsItem::ItemIsSelectable, true);
 	graphicsItem()->setFlag(QGraphicsItem::ItemSendsGeometryChanges, true);
 	graphicsItem()->setFlag(QGraphicsItem::ItemIsFocusable, true);
 }
 
 /*!
 	initializes all children of \c CartesianPlot and
 	setups a default plot of type \c type with a plot title.
 */
 void CartesianPlot::initDefault(Type type) {
 	Q_D(CartesianPlot);
 
 	switch (type) {
 	case FourAxes: {
 			d->xMin = 0;
 			d->xMax = 1;
 			d->yMin = 0;
 			d->yMax = 1;
 
 			//Axes
 			Axis* axis = new Axis("x axis 1", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisBottom);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksIn);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksIn);
 			axis->setMinorTicksNumber(1);
 			QPen pen = axis->majorGridPen();
 			pen.setStyle(Qt::SolidLine);
 			axis->setMajorGridPen(pen);
 			pen = axis->minorGridPen();
 			pen.setStyle(Qt::DotLine);
 			axis->setMinorGridPen(pen);
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("x axis 2", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisTop);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksIn);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksIn);
 			axis->setMinorTicksNumber(1);
 			axis->setLabelsPosition(Axis::NoLabels);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 1", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisLeft);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksIn);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksIn);
 			axis->setMinorTicksNumber(1);
 			pen = axis->majorGridPen();
 			pen.setStyle(Qt::SolidLine);
 			axis->setMajorGridPen(pen);
 			pen = axis->minorGridPen();
 			pen.setStyle(Qt::DotLine);
 			axis->setMinorGridPen(pen);
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 2", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisRight);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setOffset(1);
 			axis->setMajorTicksDirection(Axis::ticksIn);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksIn);
 			axis->setMinorTicksNumber(1);
 			axis->setLabelsPosition(Axis::NoLabels);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			break;
 		}
 	case TwoAxes: {
 			d->xMin = 0;
 			d->xMax = 1;
 			d->yMin = 0;
 			d->yMax = 1;
 
 			Axis* axis = new Axis("x axis 1", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisBottom);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 1", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisLeft);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->setSuppressRetransform(false);
 
 			break;
 		}
 	case TwoAxesCentered: {
 			d->xMin = -0.5;
 			d->xMax = 0.5;
 			d->yMin = -0.5;
 			d->yMax = 0.5;
 
 			d->horizontalPadding = Worksheet::convertToSceneUnits(1.0, Worksheet::Centimeter);
 			d->verticalPadding = Worksheet::convertToSceneUnits(1.0, Worksheet::Centimeter);
 
 			QPen pen = m_plotArea->borderPen();
 			pen.setStyle(Qt::NoPen);
 			m_plotArea->setBorderPen(pen);
 
 			Axis* axis = new Axis("x axis 1", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisCentered);
 			axis->setStart(-0.5);
 			axis->setEnd(0.5);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 1", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisCentered);
 			axis->setStart(-0.5);
 			axis->setEnd(0.5);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			break;
 		}
 	case TwoAxesCenteredZero: {
 			d->xMin = -0.5;
 			d->xMax = 0.5;
 			d->yMin = -0.5;
 			d->yMax = 0.5;
 
 			d->horizontalPadding = Worksheet::convertToSceneUnits(1.0, Worksheet::Centimeter);
 			d->verticalPadding = Worksheet::convertToSceneUnits(1.0, Worksheet::Centimeter);
 
 			QPen pen = m_plotArea->borderPen();
 			pen.setStyle(Qt::NoPen);
 			m_plotArea->setBorderPen(pen);
 
 			Axis* axis = new Axis("x axis 1", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisCustom);
 			axis->setOffset(0);
 			axis->setStart(-0.5);
 			axis->setEnd(0.5);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 1", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisCustom);
 			axis->setOffset(0);
 			axis->setStart(-0.5);
 			axis->setEnd(0.5);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			break;
 		}
 	}
 
 	d->xMinPrev = d->xMin;
 	d->xMaxPrev = d->xMax;
 	d->yMinPrev = d->yMin;
 	d->yMaxPrev = d->yMax;
 
 	//Plot title
 	m_title = new TextLabel(this->name(), TextLabel::PlotTitle);
 	addChild(m_title);
 	m_title->setHidden(true);
 	m_title->setParentGraphicsItem(m_plotArea->graphicsItem());
 
 	//Geometry, specify the plot rect in scene coordinates.
 	//TODO: Use default settings for left, top, width, height and for min/max for the coordinate system
 	float x = Worksheet::convertToSceneUnits(2, Worksheet::Centimeter);
 	float y = Worksheet::convertToSceneUnits(2, Worksheet::Centimeter);
 	float w = Worksheet::convertToSceneUnits(10, Worksheet::Centimeter);
 	float h = Worksheet::convertToSceneUnits(10, Worksheet::Centimeter);
 
 	//all plot children are initialized -> set the geometry of the plot in scene coordinates.
 	d->rect = QRectF(x,y,w,h);
 }
 
 void CartesianPlot::initActions() {
 	//"add new" actions
 	addCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curve"), this);
 	addHistogramPlot = new QAction(QIcon::fromTheme("labplot-xy-fourier_filter-curve"), i18n("Histogram"), this);
 	addEquationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-equation-curve"), i18n("xy-curve from a mathematical equation"), this);
 // no icons yet
 	addDataReductionCurveAction = new QAction(i18n("xy-curve from a data reduction"), this);
 	addDifferentiationCurveAction = new QAction(i18n("xy-curve from a differentiation"), this);
 	addIntegrationCurveAction = new QAction(i18n("xy-curve from an integration"), this);
 	addInterpolationCurveAction = new QAction(i18n("xy-curve from an interpolation"), this);
 	addSmoothCurveAction = new QAction(i18n("xy-curve from a smooth"), this);
 	addFitCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fit-curve"), i18n("xy-curve from a fit to data"), this);
 	addFourierFilterCurveAction = new QAction(i18n("xy-curve from a Fourier filter"), this);
 	addFourierTransformCurveAction = new QAction(i18n("xy-curve from a Fourier transform"), this);
 //	addInterpolationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-interpolation-curve"), i18n("xy-curve from an interpolation"), this);
 //	addSmoothCurveAction = new QAction(QIcon::fromTheme("labplot-xy-smooth-curve"), i18n("xy-curve from a smooth"), this);
 //	addFourierFilterCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fourier_filter-curve"), i18n("xy-curve from a Fourier filter"), this);
 //	addFourierTransformCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fourier_transform-curve"), i18n("xy-curve from a Fourier transform"), this);
 	addLegendAction = new QAction(QIcon::fromTheme("text-field"), i18n("legend"), this);
 	if (children<CartesianPlotLegend>().size()>0)
 		addLegendAction->setEnabled(false);	//only one legend is allowed -> disable the action
 
 	addHorizontalAxisAction = new QAction(QIcon::fromTheme("labplot-axis-horizontal"), i18n("horizontal axis"), this);
 	addVerticalAxisAction = new QAction(QIcon::fromTheme("labplot-axis-vertical"), i18n("vertical axis"), this);
 	addCustomPointAction = new QAction(QIcon::fromTheme("draw-cross"), i18n("custom point"), this);
 
 	connect(addCurveAction, SIGNAL(triggered()), SLOT(addCurve()));
 	connect(addHistogramPlot,SIGNAL(triggered()), SLOT(addHistogram()));
 	connect(addEquationCurveAction, SIGNAL(triggered()), SLOT(addEquationCurve()));
 	connect(addDataReductionCurveAction, SIGNAL(triggered()), SLOT(addDataReductionCurve()));
 	connect(addDifferentiationCurveAction, SIGNAL(triggered()), SLOT(addDifferentiationCurve()));
 	connect(addIntegrationCurveAction, SIGNAL(triggered()), SLOT(addIntegrationCurve()));
 	connect(addInterpolationCurveAction, SIGNAL(triggered()), SLOT(addInterpolationCurve()));
 	connect(addSmoothCurveAction, SIGNAL(triggered()), SLOT(addSmoothCurve()));
 	connect(addFitCurveAction, SIGNAL(triggered()), SLOT(addFitCurve()));
 	connect(addFourierFilterCurveAction, SIGNAL(triggered()), SLOT(addFourierFilterCurve()));
 	connect(addFourierTransformCurveAction, SIGNAL(triggered()), SLOT(addFourierTransformCurve()));
 	connect(addLegendAction, SIGNAL(triggered()), SLOT(addLegend()));
 	connect(addHorizontalAxisAction, SIGNAL(triggered()), SLOT(addHorizontalAxis()));
 	connect(addVerticalAxisAction, SIGNAL(triggered()), SLOT(addVerticalAxis()));
 	connect(addCustomPointAction, SIGNAL(triggered()), SLOT(addCustomPoint()));
 
 	//Analysis menu actions
 	addDataOperationAction = new QAction(i18n("Data operation"), this);
 	addDataReductionAction = new QAction(i18n("Reduce data"), this);
 	addDifferentiationAction = new QAction(i18n("Differentiate"), this);
 	addIntegrationAction = new QAction(i18n("Integrate"), this);
 	addInterpolationAction = new QAction(i18n("Interpolate"), this);
 	addSmoothAction = new QAction(i18n("Smooth"), this);
 
 	QAction* fitAction = new QAction(i18n("Linear"), this);
 	fitAction->setData(PlotDataDialog::FitLinear);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Power"), this);
 	fitAction->setData(PlotDataDialog::FitPower);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Exponential (degree 1)"), this);
 	fitAction->setData(PlotDataDialog::FitExp1);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Exponential (degree 2)"), this);
 	fitAction->setData(PlotDataDialog::FitExp2);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Inverse exponential"), this);
 	fitAction->setData(PlotDataDialog::FitInvExp);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Gauss"), this);
 	fitAction->setData(PlotDataDialog::FitGauss);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Cauchy-Lorentz"), this);
 	fitAction->setData(PlotDataDialog::FitCauchyLorentz);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Arc Tangent"), this);
 	fitAction->setData(PlotDataDialog::FitTan);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Hyperbolic tangent"), this);
 	fitAction->setData(PlotDataDialog::FitTanh);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Error function"), this);
 	fitAction->setData(PlotDataDialog::FitErrFunc);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Custom"), this);
 	fitAction->setData(PlotDataDialog::FitCustom);
 	addFitAction.append(fitAction);
 
 	addFourierFilterAction = new QAction(i18n("Fourier filter"), this);
 
 	connect(addDataReductionAction, SIGNAL(triggered()), SLOT(addDataReductionCurve()));
 	connect(addDifferentiationAction, SIGNAL(triggered()), SLOT(addDifferentiationCurve()));
 	connect(addIntegrationAction, SIGNAL(triggered()), SLOT(addIntegrationCurve()));
 	connect(addInterpolationAction, SIGNAL(triggered()), SLOT(addInterpolationCurve()));
 	connect(addSmoothAction, SIGNAL(triggered()), SLOT(addSmoothCurve()));
 	for (const auto& action: addFitAction)
 		connect(action, SIGNAL(triggered()), SLOT(addFitCurve()));
 	connect(addFourierFilterAction, SIGNAL(triggered()), SLOT(addFourierFilterCurve()));
 
 	//zoom/navigate actions
 	scaleAutoAction = new QAction(QIcon::fromTheme("labplot-auto-scale-all"), i18n("auto scale"), this);
 	scaleAutoXAction = new QAction(QIcon::fromTheme("labplot-auto-scale-x"), i18n("auto scale X"), this);
 	scaleAutoYAction = new QAction(QIcon::fromTheme("labplot-auto-scale-y"), i18n("auto scale Y"), this);
 	zoomInAction = new QAction(QIcon::fromTheme("zoom-in"), i18n("zoom in"), this);
 	zoomOutAction = new QAction(QIcon::fromTheme("zoom-out"), i18n("zoom out"), this);
 	zoomInXAction = new QAction(QIcon::fromTheme("labplot-zoom-in-x"), i18n("zoom in X"), this);
 	zoomOutXAction = new QAction(QIcon::fromTheme("labplot-zoom-out-x"), i18n("zoom out X"), this);
 	zoomInYAction = new QAction(QIcon::fromTheme("labplot-zoom-in-y"), i18n("zoom in Y"), this);
 	zoomOutYAction = new QAction(QIcon::fromTheme("labplot-zoom-out-y"), i18n("zoom out Y"), this);
 	shiftLeftXAction = new QAction(QIcon::fromTheme("labplot-shift-left-x"), i18n("shift left X"), this);
 	shiftRightXAction = new QAction(QIcon::fromTheme("labplot-shift-right-x"), i18n("shift right X"), this);
 	shiftUpYAction = new QAction(QIcon::fromTheme("labplot-shift-up-y"), i18n("shift up Y"), this);
 	shiftDownYAction = new QAction(QIcon::fromTheme("labplot-shift-down-y"), i18n("shift down Y"), this);
 
 	connect(scaleAutoAction, SIGNAL(triggered()), SLOT(scaleAuto()));
 	connect(scaleAutoXAction, SIGNAL(triggered()), SLOT(scaleAutoX()));
 	connect(scaleAutoYAction, SIGNAL(triggered()), SLOT(scaleAutoY()));
 	connect(zoomInAction, SIGNAL(triggered()), SLOT(zoomIn()));
 	connect(zoomOutAction, SIGNAL(triggered()), SLOT(zoomOut()));
 	connect(zoomInXAction, SIGNAL(triggered()), SLOT(zoomInX()));
 	connect(zoomOutXAction, SIGNAL(triggered()), SLOT(zoomOutX()));
 	connect(zoomInYAction, SIGNAL(triggered()), SLOT(zoomInY()));
 	connect(zoomOutYAction, SIGNAL(triggered()), SLOT(zoomOutY()));
 	connect(shiftLeftXAction, SIGNAL(triggered()), SLOT(shiftLeftX()));
 	connect(shiftRightXAction, SIGNAL(triggered()), SLOT(shiftRightX()));
 	connect(shiftUpYAction, SIGNAL(triggered()), SLOT(shiftUpY()));
 	connect(shiftDownYAction, SIGNAL(triggered()), SLOT(shiftDownY()));
 
 	//visibility action
 	visibilityAction = new QAction(i18n("visible"), this);
 	visibilityAction->setCheckable(true);
 	connect(visibilityAction, SIGNAL(triggered()), this, SLOT(visibilityChanged()));
 }
 
 void CartesianPlot::initMenus() {
 	initActions();
 
 	addNewMenu = new QMenu(i18n("Add new"));
 	addNewMenu->addAction(addCurveAction);
 // 	addNewMenu->addAction(addHistogramPlot);
 	addNewMenu->addAction(addEquationCurveAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addDataReductionCurveAction);
 	addNewMenu->addAction(addDifferentiationCurveAction);
 	addNewMenu->addAction(addIntegrationCurveAction);
 	addNewMenu->addAction(addInterpolationCurveAction);
 	addNewMenu->addAction(addSmoothCurveAction);
 	addNewMenu->addAction(addFitCurveAction);
 	addNewMenu->addAction(addFourierFilterCurveAction);
 	addNewMenu->addAction(addFourierTransformCurveAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addLegendAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addHorizontalAxisAction);
 	addNewMenu->addAction(addVerticalAxisAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addCustomPointAction);
 
 	zoomMenu = new QMenu(i18n("Zoom"));
 	zoomMenu->addAction(scaleAutoAction);
 	zoomMenu->addAction(scaleAutoXAction);
 	zoomMenu->addAction(scaleAutoYAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(zoomInAction);
 	zoomMenu->addAction(zoomOutAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(zoomInXAction);
 	zoomMenu->addAction(zoomOutXAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(zoomInYAction);
 	zoomMenu->addAction(zoomOutYAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(shiftLeftXAction);
 	zoomMenu->addAction(shiftRightXAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(shiftUpYAction);
 	zoomMenu->addAction(shiftDownYAction);
 
 	// Data manipulation menu
 	QMenu* dataManipulationMenu = new QMenu(i18n("Data Manipulation"));
 	dataManipulationMenu->setIcon(QIcon::fromTheme("zoom-draw"));
 	dataManipulationMenu->addAction(addDataOperationAction);
 	dataManipulationMenu->addAction(addDataReductionAction);
 
 	// Data fit menu
 	QMenu* dataFitMenu = new QMenu(i18n("Fit"));
 	dataFitMenu->setIcon(QIcon::fromTheme("labplot-xy-fit-curve"));
 	dataFitMenu->addAction(addFitAction.at(0));
 	dataFitMenu->addAction(addFitAction.at(1));
 	dataFitMenu->addAction(addFitAction.at(2));
 	dataFitMenu->addAction(addFitAction.at(3));
 	dataFitMenu->addAction(addFitAction.at(4));
 	dataFitMenu->addSeparator();
 	dataFitMenu->addAction(addFitAction.at(5));
 	dataFitMenu->addAction(addFitAction.at(6));
 	dataFitMenu->addSeparator();
 	dataFitMenu->addAction(addFitAction.at(7));
 	dataFitMenu->addAction(addFitAction.at(8));
 	dataFitMenu->addAction(addFitAction.at(9));
 	dataFitMenu->addSeparator();
 	dataFitMenu->addAction(addFitAction.at(10));
 
 	//analysis menu
 	dataAnalysisMenu = new QMenu(i18n("Analysis"));
 	dataAnalysisMenu->insertMenu(0, dataManipulationMenu);
 	dataAnalysisMenu->addSeparator();
 	dataAnalysisMenu->addAction(addDifferentiationAction);
 	dataAnalysisMenu->addAction(addIntegrationAction);
 	dataAnalysisMenu->addSeparator();
 	dataAnalysisMenu->addAction(addInterpolationAction);
 	dataAnalysisMenu->addAction(addSmoothAction);
 	dataAnalysisMenu->addAction(addFourierFilterAction);
 	dataAnalysisMenu->addSeparator();
 	dataAnalysisMenu->addMenu(dataFitMenu);
 
 	//themes menu
 	themeMenu = new QMenu(i18n("Apply Theme"));
 	ThemesWidget* themeWidget = new ThemesWidget(0);
 	connect(themeWidget, SIGNAL(themeSelected(QString)), this, SLOT(loadTheme(QString)));
 	connect(themeWidget, SIGNAL(themeSelected(QString)), themeMenu, SLOT(close()));
 
 	QWidgetAction* widgetAction = new QWidgetAction(this);
 	widgetAction->setDefaultWidget(themeWidget);
 	themeMenu->addAction(widgetAction);
 
 	m_menusInitialized = true;
 }
 
 QMenu* CartesianPlot::createContextMenu() {
 	if (!m_menusInitialized)
 		initMenus();
 
 	QMenu* menu = WorksheetElement::createContextMenu();
 	QAction* firstAction = menu->actions().at(1);
 
 	visibilityAction->setChecked(isVisible());
 	menu->insertAction(firstAction, visibilityAction);
 
 	menu->insertMenu(firstAction, addNewMenu);
 	menu->insertMenu(firstAction, zoomMenu);
 	menu->insertSeparator(firstAction);
 	menu->insertMenu(firstAction, themeMenu);
 	menu->insertSeparator(firstAction);
 
 	return menu;
 }
 
 QMenu* CartesianPlot::analysisMenu() {
 	if (!m_menusInitialized)
 		initMenus();
 
 	return dataAnalysisMenu;
 }
 
 /*!
 	Returns an icon to be used in the project explorer.
 */
 QIcon CartesianPlot::icon() const {
 	return QIcon::fromTheme("office-chart-line");
 }
 
 QVector<AbstractAspect*> CartesianPlot::dependsOn() const {
 	//aspects which the plotted data in the worksheet depends on (spreadsheets and later matrices)
 	QVector<AbstractAspect*> aspects;
 
 	for (const auto* curve : children<XYCurve>()) {
 		if (curve->xColumn() && dynamic_cast<Spreadsheet*>(curve->xColumn()->parentAspect()) )
 			aspects << curve->xColumn()->parentAspect();
 
 		if (curve->yColumn() && dynamic_cast<Spreadsheet*>(curve->yColumn()->parentAspect()) )
 			aspects << curve->yColumn()->parentAspect();
 	}
 
 	return aspects;
 }
 
 void CartesianPlot::navigate(CartesianPlot::NavigationOperation op) {
 	if (op == ScaleAuto) scaleAuto();
 	else if (op == ScaleAutoX) scaleAutoX();
 	else if (op == ScaleAutoY) scaleAutoY();
 	else if (op == ZoomIn) zoomIn();
 	else if (op == ZoomOut) zoomOut();
 	else if (op == ZoomInX) zoomInX();
 	else if (op == ZoomOutX) zoomOutX();
 	else if (op == ZoomInY) zoomInY();
 	else if (op == ZoomOutY) zoomOutY();
 	else if (op == ShiftLeftX) shiftLeftX();
 	else if (op == ShiftRightX) shiftRightX();
 	else if (op == ShiftUpY) shiftUpY();
 	else if (op == ShiftDownY) shiftDownY();
 }
 
 void CartesianPlot::setSuppressDataChangedSignal(bool value) {
 	Q_D(CartesianPlot);
 	d->suppressRetransform = value;
 }
 
 void CartesianPlot::processDropEvent(QDropEvent* event) {
 	PERFTRACE("CartesianPlot::processDropEvent");
 	const QMimeData* mimeData = event->mimeData();
 	if (!mimeData)
 		return;
 
 	//deserialize the mime data to the vector of aspect pointers
 	QByteArray data = mimeData->data(QLatin1String("labplot-dnd"));
 	QVector<quintptr> vec;
 	QDataStream stream(&data, QIODevice::ReadOnly);
 	stream >> vec;
 	QVector<AbstractColumn*> columns;
 	for (auto i : vec) {
 		AbstractAspect* aspect = (AbstractAspect*)i;
 		AbstractColumn* column = dynamic_cast<AbstractColumn*>(aspect);
 		if (column)
 			columns << column;
 	}
 
 	//return if there are no columns being dropped.
 	//TODO: extend this later when we allow to drag&drop plots, etc.
 	if (columns.isEmpty())
 		return;
 
 	//determine the first column with "x plot designation" as the x-data column for all curves to be created
 	const AbstractColumn* xColumn = nullptr;
 	for (const auto* column : columns) {
 		if (column->plotDesignation() == AbstractColumn::X) {
 			xColumn = column;
 			break;
 		}
 	}
 
 	//if no column with "x plot designation" is available, use the x-data column of the first curve in the plot,
 	if (xColumn == nullptr) {
 		QVector<XYCurve*> curves = children<XYCurve>();
 		if (!curves.isEmpty())
 			xColumn = curves.at(0)->xColumn();
 	}
 
 	//use the first dropped column if no column with "x plot designation" nor curves are available
 	if (xColumn == nullptr)
 		xColumn = columns.at(0);
 
 	//create curves
 	bool curvesAdded = false;
 	for (const auto* column : columns) {
 		if (column == xColumn)
 			continue;
 
 		XYCurve* curve = new XYCurve(column->name());
 		curve->suppressRetransform(true); //suppress retransform, all curved will be recalculated at the end
 		curve->setXColumn(xColumn);
 		curve->setYColumn(column);
 		addChild(curve);
 		curve->suppressRetransform(false);
 		curvesAdded = true;
 	}
 
 	if (curvesAdded)
 		dataChanged();
 }
 
+
+bool CartesianPlot::isPanningActive() const {
+	Q_D(const CartesianPlot);
+	return d->panningStarted;
+}
+
 //##############################################################################
 //################################  getter methods  ############################
 //##############################################################################
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::RangeType, rangeType, rangeType)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, int, rangeLastValues, rangeLastValues)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, int, rangeFirstValues, rangeFirstValues)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, bool, autoScaleX, autoScaleX)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, double, xMin, xMin)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, double, xMax, xMax)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::Scale, xScale, xScale)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, bool, xRangeBreakingEnabled, xRangeBreakingEnabled)
 CLASS_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::RangeBreaks, xRangeBreaks, xRangeBreaks)
 
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, bool, autoScaleY, autoScaleY)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, double, yMin, yMin)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, double, yMax, yMax)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::Scale, yScale, yScale)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, bool, yRangeBreakingEnabled, yRangeBreakingEnabled)
 CLASS_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::RangeBreaks, yRangeBreaks, yRangeBreaks)
 
 CLASS_SHARED_D_READER_IMPL(CartesianPlot, QString, theme, theme)
 
 /*!
 	returns the actual bounding rectangular of the plot area showing data (plot's rectangular minus padding)
 	in plot's coordinates
  */
 QRectF CartesianPlot::dataRect() const {
 	Q_D(const CartesianPlot);
 	return d->dataRect;
 }
 
 CartesianPlot::MouseMode CartesianPlot::mouseMode() const {
 	Q_D(const CartesianPlot);
 	return d->mouseMode;
 }
 
 //##############################################################################
 //######################  setter methods and undo commands  ####################
 //##############################################################################
 /*!
 	set the rectangular, defined in scene coordinates
  */
 class CartesianPlotSetRectCmd : public QUndoCommand {
 public:
 	CartesianPlotSetRectCmd(CartesianPlotPrivate* private_obj, QRectF rect) : m_private(private_obj), m_rect(rect) {
 		setText(i18n("%1: change geometry rect", m_private->name()));
 	};
 
 	void redo() override {
 		QRectF tmp = m_private->rect;
 		//TODO:
 // 		const double horizontalRatio = m_rect.width() / m_private->rect.width();
 // 		const double verticalRatio = m_rect.height() / m_private->rect.height();
 // 		m_private->q->handleResize(horizontalRatio, verticalRatio, false);
 		m_private->rect = m_rect;
 		m_rect = tmp;
 		m_private->retransform();
 		emit m_private->q->rectChanged(m_private->rect);
 	};
 
 	void undo() override {
 		redo();
 	}
 
 private:
 	CartesianPlotPrivate* m_private;
 	QRectF m_rect;
 };
 
 void CartesianPlot::setRect(const QRectF& rect) {
 	Q_D(CartesianPlot);
 	if (rect != d->rect)
 		exec(new CartesianPlotSetRectCmd(d, rect));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetRangeType, CartesianPlot::RangeType, rangeType, rangeChanged);
 void CartesianPlot::setRangeType(RangeType type) {
 	Q_D(CartesianPlot);
 	if (type != d->rangeType)
 		exec(new CartesianPlotSetRangeTypeCmd(d, type, i18n("%1: set range type")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetRangeLastValues, int, rangeLastValues, rangeChanged);
 void CartesianPlot::setRangeLastValues(int values) {
 	Q_D(CartesianPlot);
 	if (values != d->rangeLastValues)
 		exec(new CartesianPlotSetRangeLastValuesCmd(d, values, i18n("%1: set range")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetRangeFirstValues, int, rangeFirstValues, rangeChanged);
 void CartesianPlot::setRangeFirstValues(int values) {
 	Q_D(CartesianPlot);
 	if (values != d->rangeFirstValues)
 		exec(new CartesianPlotSetRangeFirstValuesCmd(d, values, i18n("%1: set range")));
 }
 
 
 class CartesianPlotSetAutoScaleXCmd : public QUndoCommand {
 public:
 	CartesianPlotSetAutoScaleXCmd(CartesianPlotPrivate* private_obj, bool autoScale) :
 		m_private(private_obj), m_autoScale(autoScale), m_minOld(0.0), m_maxOld(0.0) {
 		setText(i18n("%1: change x-range auto scaling", m_private->name()));
 	};
 
 	void redo() override {
 		m_autoScaleOld = m_private->autoScaleX;
 		if (m_autoScale) {
 			m_minOld = m_private->xMin;
 			m_maxOld = m_private->xMax;
 			m_private->q->scaleAutoX();
 		}
 		m_private->autoScaleX = m_autoScale;
 		emit m_private->q->xAutoScaleChanged(m_autoScale);
 	};
 
 	void undo() override {
 		if (!m_autoScaleOld) {
 			m_private->xMin = m_minOld;
 			m_private->xMax = m_maxOld;
 			m_private->retransformScales();
 		}
 		m_private->autoScaleX = m_autoScaleOld;
 		emit m_private->q->xAutoScaleChanged(m_autoScaleOld);
 	}
 
 private:
 	CartesianPlotPrivate* m_private;
 	bool m_autoScale;
 	bool m_autoScaleOld;
 	double m_minOld;
 	double m_maxOld;
 };
 
 void CartesianPlot::setAutoScaleX(bool autoScaleX) {
 	Q_D(CartesianPlot);
 	if (autoScaleX != d->autoScaleX)
 		exec(new CartesianPlotSetAutoScaleXCmd(d, autoScaleX));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXMin, double, xMin, retransformScales)
 void CartesianPlot::setXMin(double xMin) {
 	Q_D(CartesianPlot);
 	if (xMin != d->xMin)
 		exec(new CartesianPlotSetXMinCmd(d, xMin, i18n("%1: set min x")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXMax, double, xMax, retransformScales)
 void CartesianPlot::setXMax(double xMax) {
 	Q_D(CartesianPlot);
 	if (xMax != d->xMax)
 		exec(new CartesianPlotSetXMaxCmd(d, xMax, i18n("%1: set max x")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXScale, CartesianPlot::Scale, xScale, retransformScales)
 void CartesianPlot::setXScale(Scale scale) {
 	Q_D(CartesianPlot);
 	if (scale != d->xScale)
 		exec(new CartesianPlotSetXScaleCmd(d, scale, i18n("%1: set x scale")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXRangeBreakingEnabled, bool, xRangeBreakingEnabled, retransformScales)
 void CartesianPlot::setXRangeBreakingEnabled(bool enabled) {
 	Q_D(CartesianPlot);
 	if (enabled != d->xRangeBreakingEnabled)
 		exec(new CartesianPlotSetXRangeBreakingEnabledCmd(d, enabled, i18n("%1: x-range breaking enabled")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXRangeBreaks, CartesianPlot::RangeBreaks, xRangeBreaks, retransformScales)
 void CartesianPlot::setXRangeBreaks(const RangeBreaks& breakings) {
 	Q_D(CartesianPlot);
 	exec(new CartesianPlotSetXRangeBreaksCmd(d, breakings, i18n("%1: x-range breaks changed")));
 }
 
 class CartesianPlotSetAutoScaleYCmd : public QUndoCommand {
 public:
 	CartesianPlotSetAutoScaleYCmd(CartesianPlotPrivate* private_obj, bool autoScale) :
 		m_private(private_obj), m_autoScale(autoScale), m_minOld(0.0), m_maxOld(0.0) {
 		setText(i18n("%1: change y-range auto scaling", m_private->name()));
 	};
 
 	void redo() override {
 		m_autoScaleOld = m_private->autoScaleY;
 		if (m_autoScale) {
 			m_minOld = m_private->yMin;
 			m_maxOld = m_private->yMax;
 			m_private->q->scaleAutoY();
 		}
 		m_private->autoScaleY = m_autoScale;
 		emit m_private->q->yAutoScaleChanged(m_autoScale);
 	};
 
 	void undo() override {
 		if (!m_autoScaleOld) {
 			m_private->yMin = m_minOld;
 			m_private->yMax = m_maxOld;
 			m_private->retransformScales();
 		}
 		m_private->autoScaleY = m_autoScaleOld;
 		emit m_private->q->yAutoScaleChanged(m_autoScaleOld);
 	}
 
 private:
 	CartesianPlotPrivate* m_private;
 	bool m_autoScale;
 	bool m_autoScaleOld;
 	double m_minOld;
 	double m_maxOld;
 };
 
 void CartesianPlot::setAutoScaleY(bool autoScaleY) {
 	Q_D(CartesianPlot);
 	if (autoScaleY != d->autoScaleY)
 		exec(new CartesianPlotSetAutoScaleYCmd(d, autoScaleY));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYMin, double, yMin, retransformScales)
 void CartesianPlot::setYMin(double yMin) {
 	Q_D(CartesianPlot);
 	if (yMin != d->yMin)
 		exec(new CartesianPlotSetYMinCmd(d, yMin, i18n("%1: set min y")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYMax, double, yMax, retransformScales)
 void CartesianPlot::setYMax(double yMax) {
 	Q_D(CartesianPlot);
 	if (yMax != d->yMax)
 		exec(new CartesianPlotSetYMaxCmd(d, yMax, i18n("%1: set max y")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYScale, CartesianPlot::Scale, yScale, retransformScales)
 void CartesianPlot::setYScale(Scale scale) {
 	Q_D(CartesianPlot);
 	if (scale != d->yScale)
 		exec(new CartesianPlotSetYScaleCmd(d, scale, i18n("%1: set y scale")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYRangeBreakingEnabled, bool, yRangeBreakingEnabled, retransformScales)
 void CartesianPlot::setYRangeBreakingEnabled(bool enabled) {
 	Q_D(CartesianPlot);
 	if (enabled != d->yRangeBreakingEnabled)
 		exec(new CartesianPlotSetYRangeBreakingEnabledCmd(d, enabled, i18n("%1: y-range breaking enabled")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYRangeBreaks, CartesianPlot::RangeBreaks, yRangeBreaks, retransformScales)
 void CartesianPlot::setYRangeBreaks(const RangeBreaks& breaks) {
 	Q_D(CartesianPlot);
 	exec(new CartesianPlotSetYRangeBreaksCmd(d, breaks, i18n("%1: y-range breaks changed")));
 }
 
 STD_SETTER_CMD_IMPL_S(CartesianPlot, SetTheme, QString, theme)
 void CartesianPlot::setTheme(const QString& theme) {
 	Q_D(CartesianPlot);
 	if (theme != d->theme) {
 		if (!theme.isEmpty()) {
 			beginMacro( i18n("%1: load theme %2", name(), theme) );
 			exec(new CartesianPlotSetThemeCmd(d, theme, i18n("%1: set theme")));
 			loadTheme(theme);
 			endMacro();
 		} else
 			exec(new CartesianPlotSetThemeCmd(d, theme, i18n("%1: disable theming")));
 	}
 }
 
 //################################################################
 //########################## Slots ###############################
 //################################################################
 void CartesianPlot::addHorizontalAxis() {
 	Axis* axis = new Axis("x-axis", Axis::AxisHorizontal);
 	if (axis->autoScale()) {
 		axis->setUndoAware(false);
 		axis->setStart(xMin());
 		axis->setEnd(xMax());
 		axis->setUndoAware(true);
 	}
 	addChild(axis);
 }
 
 void CartesianPlot::addVerticalAxis() {
 	Axis* axis = new Axis("y-axis", Axis::AxisVertical);
 	if (axis->autoScale()) {
 		axis->setUndoAware(false);
 		axis->setStart(yMin());
 		axis->setEnd(yMax());
 		axis->setUndoAware(true);
 	}
 	addChild(axis);
 }
 
 void CartesianPlot::addCurve() {
 	addChild(new XYCurve("xy-curve"));
 }
 
 void CartesianPlot::addEquationCurve() {
 	addChild(new XYEquationCurve("f(x)"));
 }
 
 void CartesianPlot::addHistogram() {
 	addChild(new Histogram("Histogram"));
 }
 
 /*!
  * returns the first selected XYCurve in the plot
  */
 const XYCurve* CartesianPlot::currentCurve() const {
 	for (const auto* curve: this->children<const XYCurve>()) {
 		if (curve->graphicsItem()->isSelected())
 			return curve;
 	}
 
 	return 0;
 }
 
 void CartesianPlot::addDataReductionCurve() {
 	XYDataReductionCurve* curve = new XYDataReductionCurve("Data reduction");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: reduce '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Reduction of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->dataReductionDataChanged(curve->dataReductionData());
 	} else {
 		beginMacro(i18n("%1: add data reduction curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addDifferentiationCurve() {
 	XYDifferentiationCurve* curve = new XYDifferentiationCurve("Differentiation");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: differentiate '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Derivative of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->differentiationDataChanged(curve->differentiationData());
 	} else {
 		beginMacro(i18n("%1: add differentiation curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addIntegrationCurve() {
 	XYIntegrationCurve* curve = new XYIntegrationCurve("Integration");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: integrate '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Integral of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->integrationDataChanged(curve->integrationData());
 	} else {
 		beginMacro(i18n("%1: add differentiation curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addInterpolationCurve() {
 	XYInterpolationCurve* curve = new XYInterpolationCurve("Interpolation");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: interpolate '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Interpolation of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		curve->recalculate();
 		this->addChild(curve);
 		emit curve->interpolationDataChanged(curve->interpolationData());
 	} else {
 		beginMacro(i18n("%1: add interpolation curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addSmoothCurve() {
 	XYSmoothCurve* curve = new XYSmoothCurve("Smooth");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: smooth '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Smoothing of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->smoothDataChanged(curve->smoothData());
 	} else {
 		beginMacro(i18n("%1: add smoothing curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addFitCurve() {
 	DEBUG("CartesianPlot::addFitCurve()");
 	XYFitCurve* curve = new XYFitCurve("fit");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: fit to '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Fit to '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 
 
 		//set the fit model category and type
 		const QAction* action = qobject_cast<const QAction*>(QObject::sender());
 		PlotDataDialog::AnalysisAction type = (PlotDataDialog::AnalysisAction)action->data().toInt();
 		curve->initFitData(type);
 		curve->initStartValues(curCurve);
 
 		//fit with weights for y if the curve has error bars for y
 		if (curCurve->yErrorType() == XYCurve::SymmetricError && curCurve->yErrorPlusColumn()) {
 			XYFitCurve::FitData fitData = curve->fitData();
 			fitData.yWeightsType = nsl_fit_weight_instrumental;
 			curve->setFitData(fitData);
 			curve->setYErrorColumn(curCurve->yErrorPlusColumn());
 		}
 
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->fitDataChanged(curve->fitData());
 	} else {
 		beginMacro(i18n("%1: add fit curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addFourierFilterCurve() {
 	XYFourierFilterCurve* curve = new XYFourierFilterCurve("Fourier filter");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: Fourier filtering of '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Fourier filtering of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 	} else {
 		beginMacro(i18n("%1: add Fourier filter curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addFourierTransformCurve() {
 	XYFourierTransformCurve* curve = new XYFourierTransformCurve("Fourier transform");
 	this->addChild(curve);
 }
 
 void CartesianPlot::addLegend() {
 	//don't do anything if there's already a legend
 	if (m_legend)
 		return;
 
 	m_legend = new CartesianPlotLegend(this, "legend");
 	this->addChild(m_legend);
 	m_legend->retransform();
 
 	//only one legend is allowed -> disable the action
 	if (m_menusInitialized)
 		addLegendAction->setEnabled(false);
 }
 
 void CartesianPlot::addCustomPoint() {
 	CustomPoint* point = new CustomPoint(this, "custom point");
 	this->addChild(point);
 }
 
 void CartesianPlot::childAdded(const AbstractAspect* child) {
 	Q_D(CartesianPlot);
 	const XYCurve* curve = qobject_cast<const XYCurve*>(child);
 	if (curve) {
 		connect(curve, SIGNAL(dataChanged()), this, SLOT(dataChanged()));
 		connect(curve, SIGNAL(xDataChanged()), this, SLOT(xDataChanged()));
 		connect(curve, SIGNAL(yDataChanged()), this, SLOT(yDataChanged()));
 		connect(curve, SIGNAL(visibilityChanged(bool)), this, SLOT(curveVisibilityChanged()));
 
 		//update the legend on changes of the name, line and symbol styles
 		connect(curve, SIGNAL(aspectDescriptionChanged(const AbstractAspect*)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(lineTypeChanged(XYCurve::LineType)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(linePenChanged(QPen)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(lineOpacityChanged(qreal)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsStyleChanged(Symbol::Style)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsSizeChanged(qreal)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsRotationAngleChanged(qreal)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsOpacityChanged(qreal)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsBrushChanged(QBrush)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsPenChanged(QPen)), this, SLOT(updateLegend()));
 
 		updateLegend();
 		d->curvesXMinMaxIsDirty = true;
 		d->curvesYMinMaxIsDirty = true;
 	} else {
 		const Histogram* histo = qobject_cast<const Histogram*>(child);
 		if (histo) {
 			connect(histo, SIGNAL(HistogramdataChanged()), this, SLOT(HistogramdataChanged()));
 			connect(histo, SIGNAL(xHistogramDataChanged()), this, SLOT(xHistogramDataChanged()));
 			connect(histo, SIGNAL(yHistogramDataChanged()), this, SLOT(yHistogramDataChanged()));
 			connect(histo, SIGNAL(visibilityChanged(bool)), this, SLOT(curveVisibilityChanged()));
 		}
 	}
 
 	//if a theme was selected, apply the theme settings for newly added children, too
 	if (!d->theme.isEmpty() && !isLoading()) {
 		const WorksheetElement* el = dynamic_cast<const WorksheetElement*>(child);
 		if (el) {
 			KConfig config(ThemeHandler::themeFilePath(d->theme), KConfig::SimpleConfig);
 			const_cast<WorksheetElement*>(el)->loadThemeConfig(config);
 		}
 	}
 }
 
 void CartesianPlot::childRemoved(const AbstractAspect* parent, const AbstractAspect* before, const AbstractAspect* child) {
 	Q_UNUSED(parent);
 	Q_UNUSED(before);
 	if (m_legend == child) {
 		if (m_menusInitialized)
 			addLegendAction->setEnabled(true);
 		m_legend = nullptr;
 	} else {
 		const XYCurve* curve = qobject_cast<const XYCurve*>(child);
 		if (curve)
 			updateLegend();
 	}
 }
 
 void CartesianPlot::updateLegend() {
 	if (m_legend)
 		m_legend->retransform();
 }
 
 /*!
 	called when in one of the curves the data was changed.
 	Autoscales the coordinate system and the x-axes, when "auto-scale" is active.
 */
 void CartesianPlot::dataChanged() {
 	Q_D(CartesianPlot);
 	d->curvesXMinMaxIsDirty = true;
 	d->curvesYMinMaxIsDirty = true;
 	if (d->autoScaleX && d->autoScaleY)
 		this->scaleAuto();
 	else if (d->autoScaleX)
 		this->scaleAutoX();
 	else if (d->autoScaleY)
 		this->scaleAutoY();
 	else {
 		//free ranges -> rentransform the curve that sent
 		XYCurve* curve = dynamic_cast<XYCurve*>(QObject::sender());
 		if (curve)
 			curve->retransform();
 		else {
 			//no sender available, the function was called in CartesianPlot::dataChanged() (live data source got new data)
 			//-> retransform all available curves since we don't know which curves are affected.
 			//TODO: this logic can be very expensive
 			for (auto c : children<XYCurve>())
 				c->retransform();
 		}
 	}
 }
 
 void CartesianPlot::HistogramdataChanged() {
 	Q_D(CartesianPlot);
 	d->curvesXMinMaxIsDirty = true;
 	d->curvesYMinMaxIsDirty = true;
 	if (d->autoScaleX && d->autoScaleY)
 		this->scaleAuto();
 	else if (d->autoScaleX)
 		this->scaleAutoY();
 	else if (d->autoScaleY)
 		this->scaleAutoY();
 	else {
 		Histogram* curve = dynamic_cast<Histogram*>(QObject::sender());
 		if (curve)
 			curve->retransform();
 		else {
 			//no sender available, the function was called in CartesianPlot::dataChanged() (live data source got new data)
 			//-> retransform all available curves since we don't know which curves are affected.
 			//TODO: this logic can be very expensive
 			for (auto c : children<Histogram>())
 				c->retransform();
 		}
 	}
 }
 
 /*!
 	called when in one of the curves the x-data was changed.
 	Autoscales the coordinate system and the x-axes, when "auto-scale" is active.
 */
 void CartesianPlot::xDataChanged() {
 	if (project()->isLoading())
 		return;
 
 	Q_D(CartesianPlot);
 	if (d->suppressRetransform)
 		return;
 
 	d->curvesXMinMaxIsDirty = true;
 	if (d->autoScaleX)
 		this->scaleAutoX();
 	else {
 		XYCurve* curve = dynamic_cast<XYCurve*>(QObject::sender());
 		curve->retransform();
 	}
 }
 
 void CartesianPlot::xHistogramDataChanged() {
 	if (project()->isLoading())
 		return;
 
 	Q_D(CartesianPlot);
 	if (d->suppressRetransform)
 		return;
 
 	d->curvesXMinMaxIsDirty = true;
 	if (d->autoScaleX)
 		this->scaleAutoX();
 	else {
 		Histogram* curve = dynamic_cast<Histogram*>(QObject::sender());
 		curve->retransform();
 	}
 }
 /*!
 	called when in one of the curves the x-data was changed.
 	Autoscales the coordinate system and the x-axes, when "auto-scale" is active.
 */
 void CartesianPlot::yDataChanged() {
 	if (project()->isLoading())
 		return;
 
 	Q_D(CartesianPlot);
 	if (d->suppressRetransform)
 		return;
 
 	d->curvesYMinMaxIsDirty = true;
 	if (d->autoScaleY)
 		this->scaleAutoY();
 	else {
 		XYCurve* curve = dynamic_cast<XYCurve*>(QObject::sender());
 		curve->retransform();
 	}
 }
 void CartesianPlot::yHistogramDataChanged() {
 	if (project()->isLoading())
 		return;
 
 	Q_D(CartesianPlot);
 	if (d->suppressRetransform)
 		return;
 
 	d->curvesYMinMaxIsDirty = true;
 	if (d->autoScaleY)
 		this->scaleAutoY();
 	else {
 		Histogram* curve = dynamic_cast<Histogram*>(QObject::sender());
 		curve->retransform();
 	}
 }
 
 void CartesianPlot::curveVisibilityChanged() {
 	Q_D(CartesianPlot);
 	d->curvesXMinMaxIsDirty = true;
 	d->curvesYMinMaxIsDirty = true;
 	updateLegend();
 	if (d->autoScaleX && d->autoScaleY)
 		this->scaleAuto();
 	else if (d->autoScaleX)
 		this->scaleAutoX();
 	else if (d->autoScaleY)
 		this->scaleAutoY();
 }
 
 void CartesianPlot::setMouseMode(const MouseMode mouseMode) {
 	Q_D(CartesianPlot);
 
 	d->mouseMode = mouseMode;
 	d->setHandlesChildEvents(mouseMode != CartesianPlot::SelectionMode);
 
 	QList<QGraphicsItem*> items = d->childItems();
 	if (d->mouseMode == CartesianPlot::SelectionMode) {
 		for (auto* item: items)
 			item->setFlag(QGraphicsItem::ItemStacksBehindParent, false);
 	} else {
 		for (auto* item: items)
 			item->setFlag(QGraphicsItem::ItemStacksBehindParent, true);
 	}
 
 	//when doing zoom selection, prevent the graphics item from being movable
 	//if it's currently movable (no worksheet layout available)
 	const Worksheet* worksheet = dynamic_cast<const Worksheet*>(parentAspect());
 	if (worksheet) {
 		if (mouseMode == CartesianPlot::SelectionMode) {
 			if (worksheet->layout() != Worksheet::NoLayout)
 				graphicsItem()->setFlag(QGraphicsItem::ItemIsMovable, false);
 			else
 				graphicsItem()->setFlag(QGraphicsItem::ItemIsMovable, true);
 		} else   //zoom m_selection
 			graphicsItem()->setFlag(QGraphicsItem::ItemIsMovable, false);
 	}
 }
 
 void CartesianPlot::scaleAutoX() {
 	Q_D(CartesianPlot);
 	if (d->curvesXMinMaxIsDirty) {
 		int count = 0;
 		switch (d->rangeType) {
 		case CartesianPlot::RangeFree:
 			count = 0;
 			break;
 		case CartesianPlot::RangeLast:
 			count = -d->rangeLastValues;
 			break;
 		case CartesianPlot::RangeFirst:
 			count = d->rangeFirstValues;
 			break;
 		}
 
 		d->curvesXMin = INFINITY;
 		d->curvesXMax = -INFINITY;
 
 		//loop over all xy-curves and determine the maximum and minimum x-values
 		for (const auto* curve: this->children<const XYCurve>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->xColumn())
 				continue;
 
 			const double min = curve->xColumn()->minimum(count);
 			if (min < d->curvesXMin)
 				d->curvesXMin = min;
 
 			const double max = curve->xColumn()->maximum(count);
 			if (max > d->curvesXMax)
 				d->curvesXMax = max;
 		}
 
 		//loop over all histograms and determine the maximum and minimum x-values
 		for (const auto* curve: this->children<const Histogram>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->xColumn())
 				continue;
 
 			const double min = curve->xColumn()->minimum(count);
 			if (min < d->curvesXMin)
 				d->curvesXMin = min;
 
 			const double max = curve->xColumn()->maximum(count);
 			if (max > d->curvesXMax)
 				d->curvesXMax = max;
 		}
 
 		d->curvesXMinMaxIsDirty = false;
 	}
 
 	bool update = false;
 	if (d->curvesXMin != d->xMin && d->curvesXMin != INFINITY) {
 		d->xMin = d->curvesXMin;
 		update = true;
 	}
 
 	if (d->curvesXMax != d->xMax && d->curvesXMax != -INFINITY) {
 		d->xMax = d->curvesXMax;
 		update = true;
 	}
 
 	if (update) {
 		if (d->xMax == d->xMin) {
 			//in case min and max are equal (e.g. if we plot a single point), subtract/add 10% of the value
 			if (d->xMax != 0) {
 				d->xMax = d->xMax*1.1;
 				d->xMin = d->xMin*0.9;
 			} else {
 				d->xMax = 0.1;
 				d->xMin = -0.1;
 			}
 		} else {
 			double offset = (d->xMax - d->xMin)*d->autoScaleOffsetFactor;
 			d->xMin -= offset;
 			d->xMax += offset;
 		}
 		d->retransformScales();
 	}
 }
 
 void CartesianPlot::scaleAutoY() {
 	Q_D(CartesianPlot);
 
 	if (d->curvesYMinMaxIsDirty) {
 		int count = 0;
 		switch (d->rangeType) {
 		case CartesianPlot::RangeFree:
 			count = 0;
 			break;
 		case CartesianPlot::RangeLast:
 			count = -d->rangeLastValues;
 			break;
 		case CartesianPlot::RangeFirst:
 			count = d->rangeFirstValues;
 			break;
 		}
 
 		d->curvesYMin = INFINITY;
 		d->curvesYMax = -INFINITY;
 
 		//loop over all xy-curves and determine the maximum and minimum y-values
 		for (const auto* curve: this->children<const XYCurve>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->yColumn())
 				continue;
 
 			const double min = curve->yColumn()->minimum(count);
 			if (min < d->curvesYMin)
 				d->curvesYMin = min;
 
 			const double max = curve->yColumn()->maximum(count);
 			if (max > d->curvesYMax)
 				d->curvesYMax = max;
 		}
 
 		//loop over all histograms and determine the maximum y-value
 		for (const auto* curve: this->children<const Histogram>()) {
 			if (!curve->isVisible())
 				continue;
 
 			if (d->curvesYMin > 0.0)
 				d->curvesYMin = 0.0;
 
 			if ( curve->getYMaximum() > d->curvesYMax)
 				d->curvesYMax = curve->getYMaximum();
 		}
 
 		d->curvesYMinMaxIsDirty = false;
 	}
 
 
 	bool update = false;
 	if (d->curvesYMin != d->yMin && d->curvesYMin != INFINITY) {
 		d->yMin = d->curvesYMin;
 		update = true;
 	}
 
 	if (d->curvesYMax != d->yMax && d->curvesYMax != -INFINITY) {
 		d->yMax = d->curvesYMax;
 		update = true;
 	}
 
 	if (update) {
 		if (d->yMax == d->yMin) {
 			//in case min and max are equal (e.g. if we plot a single point), subtract/add 10% of the value
 			if (d->yMax != 0) {
 				d->yMax = d->yMax*1.1;
 				d->yMin = d->yMin*0.9;
 			} else {
 				d->yMax = 0.1;
 				d->yMin = -0.1;
 			}
 		} else {
 			double offset = (d->yMax - d->yMin)*d->autoScaleOffsetFactor;
 			d->yMin -= offset;
 			d->yMax += offset;
 		}
 		d->retransformScales();
 	}
 }
 
 void CartesianPlot::scaleAuto() {
 	DEBUG("CartesianPlot::scaleAuto()");
 	Q_D(CartesianPlot);
 
 	int count = 0;
 	switch (d->rangeType) {
 	case CartesianPlot::RangeFree:
 		count = 0;
 		break;
 	case CartesianPlot::RangeLast:
 		count = -d->rangeLastValues;
 		break;
 	case CartesianPlot::RangeFirst:
 		count = d->rangeFirstValues;
 		break;
 	}
 
 	if (d->curvesXMinMaxIsDirty) {
 		d->curvesXMin = INFINITY;
 		d->curvesXMax = -INFINITY;
 
 		//loop over all xy-curves and determine the maximum and minimum x-values
 		for (const auto* curve: this->children<const XYCurve>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->xColumn())
 				continue;
 
 			const double min = curve->xColumn()->minimum(count);
 			if (min < d->curvesXMin)
 				d->curvesXMin = min;
 
 			double max = curve->xColumn()->maximum(count);
 			if (max > d->curvesXMax)
 				d->curvesXMax = max;
 		}
 
 		//loop over all histograms and determine the maximum and minimum x-values
 		for (const auto* curve: this->children<const Histogram>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->xColumn())
 				continue;
 
 			const double min = curve->xColumn()->minimum(count);
 			if (min < d->curvesXMin)
 				d->curvesXMin = min;
 
 			const double max = curve->xColumn()->maximum(count);
 			if (max > d->curvesXMax)
 				d->curvesXMax = max;
 		}
 
 		d->curvesXMinMaxIsDirty = false;
 	}
 
 	if (d->curvesYMinMaxIsDirty) {
 		d->curvesYMin = INFINITY;
 		d->curvesYMax = -INFINITY;
 
 		//loop over all xy-curves and determine the maximum and minimum y-values
 		for (const auto* curve: this->children<const XYCurve>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->yColumn())
 				continue;
 
 			const double min = curve->yColumn()->minimum(count);
 			if (min < d->curvesYMin)
 				d->curvesYMin = min;
 
 			const double max = curve->yColumn()->maximum(count);
 			if (max > d->curvesYMax)
 				d->curvesYMax = max;
 		}
 
 		//loop over all histograms and determine the maximum y-value
 		for (const auto* curve: this->children<const Histogram>()) {
 			if (!curve->isVisible())
 				continue;
 
 			if (d->curvesYMin > 0.0)
 				d->curvesYMin = 0.0;
 
 			const double max = curve->getYMaximum();
 			if (max > d->curvesYMax)
 				d->curvesYMax = max;
 		}
 	}
 
 	bool updateX = false;
 	bool updateY = false;
 	if (d->curvesXMin != d->xMin && d->curvesXMin != INFINITY) {
 		d->xMin = d->curvesXMin;
 		updateX = true;
 	}
 
 	if (d->curvesXMax != d->xMax && d->curvesXMax != -INFINITY) {
 		d->xMax = d->curvesXMax;
 		updateX = true;
 	}
 
 	if (d->curvesYMin != d->yMin && d->curvesYMin != INFINITY) {
 		d->yMin = d->curvesYMin;
 		updateY = true;
 	}
 
 	if (d->curvesYMax != d->yMax && d->curvesYMax != -INFINITY) {
 		d->yMax = d->curvesYMax;
 		updateY = true;
 	}
 	DEBUG(" xmin/xmax = " << d->xMin << '/' << d->xMax << ", ymin/ymax = " << d->yMin << '/' << d->yMax);
 
 	if (updateX || updateY) {
 		if (updateX) {
 			if (d->xMax == d->xMin) {
 				//in case min and max are equal (e.g. if we plot a single point), subtract/add 10% of the value
 				if (d->xMax != 0) {
 					d->xMax = d->xMax*1.1;
 					d->xMin = d->xMin*0.9;
 				} else {
 					d->xMax = 0.1;
 					d->xMin = -0.1;
 				}
 			} else {
 				double offset = (d->xMax - d->xMin)*d->autoScaleOffsetFactor;
 				d->xMin -= offset;
 				d->xMax += offset;
 			}
 		}
 		if (updateY) {
 			if (d->yMax == d->yMin) {
 				//in case min and max are equal (e.g. if we plot a single point), subtract/add 10% of the value
 				if (d->yMax != 0) {
 					d->yMax = d->yMax*1.1;
 					d->yMin = d->yMin*0.9;
 				} else {
 					d->yMax = 0.1;
 					d->yMin = -0.1;
 				}
 			} else {
 				double offset = (d->yMax - d->yMin)*d->autoScaleOffsetFactor;
 				d->yMin -= offset;
 				d->yMax += offset;
 			}
 		}
 		d->retransformScales();
 	}
 }
 
 void CartesianPlot::zoomIn() {
 	DEBUG("CartesianPlot::zoomIn()");
 	Q_D(CartesianPlot);
 
 	double oldRange = (d->xMax - d->xMin);
 	double newRange = (d->xMax - d->xMin) / m_zoomFactor;
 	d->xMax = d->xMax + (newRange - oldRange) / 2;
 	d->xMin = d->xMin - (newRange - oldRange) / 2;
 
 	oldRange = (d->yMax - d->yMin);
 	newRange = (d->yMax - d->yMin) / m_zoomFactor;
 	d->yMax = d->yMax + (newRange - oldRange) / 2;
 	d->yMin = d->yMin - (newRange - oldRange) / 2;
 
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomOut() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->xMax-d->xMin);
 	double newRange = (d->xMax-d->xMin)*m_zoomFactor;
 	d->xMax = d->xMax + (newRange-oldRange)/2;
 	d->xMin = d->xMin - (newRange-oldRange)/2;
 
 	oldRange = (d->yMax-d->yMin);
 	newRange = (d->yMax-d->yMin)*m_zoomFactor;
 	d->yMax = d->yMax + (newRange-oldRange)/2;
 	d->yMin = d->yMin - (newRange-oldRange)/2;
 
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomInX() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->xMax-d->xMin);
 	double newRange = (d->xMax-d->xMin)/m_zoomFactor;
 	d->xMax = d->xMax + (newRange-oldRange)/2;
 	d->xMin = d->xMin - (newRange-oldRange)/2;
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomOutX() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->xMax-d->xMin);
 	double newRange = (d->xMax-d->xMin)*m_zoomFactor;
 	d->xMax = d->xMax + (newRange-oldRange)/2;
 	d->xMin = d->xMin - (newRange-oldRange)/2;
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomInY() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->yMax-d->yMin);
 	double newRange = (d->yMax-d->yMin)/m_zoomFactor;
 	d->yMax = d->yMax + (newRange-oldRange)/2;
 	d->yMin = d->yMin - (newRange-oldRange)/2;
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomOutY() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->yMax-d->yMin);
 	double newRange = (d->yMax-d->yMin)*m_zoomFactor;
 	d->yMax = d->yMax + (newRange-oldRange)/2;
 	d->yMin = d->yMin - (newRange-oldRange)/2;
 	d->retransformScales();
 }
 
 void CartesianPlot::shiftLeftX() {
 	Q_D(CartesianPlot);
 	double offsetX = (d->xMax-d->xMin)*0.1;
 	d->xMax -= offsetX;
 	d->xMin -= offsetX;
 	d->retransformScales();
 }
 
 void CartesianPlot::shiftRightX() {
 	Q_D(CartesianPlot);
 	double offsetX = (d->xMax-d->xMin)*0.1;
 	d->xMax += offsetX;
 	d->xMin += offsetX;
 	d->retransformScales();
 }
 
 void CartesianPlot::shiftUpY() {
 	Q_D(CartesianPlot);
 	double offsetY = (d->yMax-d->yMin)*0.1;
 	d->yMax += offsetY;
 	d->yMin += offsetY;
 	d->retransformScales();
 }
 
 void CartesianPlot::shiftDownY() {
 	Q_D(CartesianPlot);
 	double offsetY = (d->yMax-d->yMin)*0.1;
 	d->yMax -= offsetY;
 	d->yMin -= offsetY;
 	d->retransformScales();
 }
 
 //##############################################################################
 //######  SLOTs for changes triggered via QActions in the context menu  ########
 //##############################################################################
 void CartesianPlot::visibilityChanged() {
 	Q_D(CartesianPlot);
 	this->setVisible(!d->isVisible());
 }
 
 //#####################################################################
 //################### Private implementation ##########################
 //#####################################################################
 CartesianPlotPrivate::CartesianPlotPrivate(CartesianPlot* plot) : AbstractPlotPrivate(plot),
 	curvesXMinMaxIsDirty(false), curvesYMinMaxIsDirty(false),
 	curvesXMin(INFINITY), curvesXMax(-INFINITY), curvesYMin(INFINITY), curvesYMax(-INFINITY),
 	q(plot),
 	mouseMode(CartesianPlot::SelectionMode),
 	cSystem(nullptr),
 	suppressRetransform(false),
 	m_selectionBandIsShown(false),
-	m_panningStarted(false) {
+	panningStarted(false) {
 
 	setData(0, WorksheetElement::NameCartesianPlot);
 }
 
 /*!
 	updates the position of plot rectangular in scene coordinates to \c r and recalculates the scales.
 	The size of the plot corresponds to the size of the plot area, the area which is filled with the background color etc.
 	and which can pose the parent item for several sub-items (like TextLabel).
 	Note, the size of the area used to define the coordinate system doesn't need to be equal to this plot area.
 	Also, the size (=bounding box) of CartesianPlot can be greater than the size of the plot area.
  */
 void CartesianPlotPrivate::retransform() {
 	if (suppressRetransform)
 		return;
 
 	PERFTRACE("CartesianPlotPrivate::retransform()");
 	prepareGeometryChange();
 	setPos( rect.x()+rect.width()/2, rect.y()+rect.height()/2);
 
 	updateDataRect();
 	retransformScales();
 
 	//plotArea position is always (0, 0) in parent's coordinates, don't need to update here
 	q->plotArea()->setRect(rect);
 
 	//call retransform() for the title and the legend (if available)
 	//when a predefined position relative to the (Left, Centered etc.) is used,
 	//the actual position needs to be updated on plot's geometry changes.
 	if (q->title())
 		q->title()->retransform();
 	if (q->m_legend)
 		q->m_legend->retransform();
 
 	WorksheetElementContainerPrivate::recalcShapeAndBoundingRect();
 }
 
 void CartesianPlotPrivate::retransformScales() {
 	PERFTRACE("CartesianPlotPrivate::retransformScales()");
 	DEBUG(" xmin/xmax = " << xMin << '/'<< xMax << ", ymin/ymax = " << yMin << '/' << yMax);
 
 	CartesianPlot* plot = dynamic_cast<CartesianPlot*>(q);
 	QVector<CartesianScale*> scales;
 
 	//perform the mapping from the scene coordinates to the plot's coordinates here.
 	QRectF itemRect = mapRectFromScene(rect);
 
 	//check ranges for log-scales
 	if (xScale != CartesianPlot::ScaleLinear)
 		checkXRange();
 
 	//check whether we have x-range breaks - the first break, if available, should be valid
 	bool hasValidBreak = (xRangeBreakingEnabled && !xRangeBreaks.list.isEmpty() && xRangeBreaks.list.first().isValid());
 
 	static const int breakGap = 20;
 	double sceneStart, sceneEnd, logicalStart, logicalEnd;
 
 	//create x-scales
 	int plotSceneStart = itemRect.x() + horizontalPadding;
 	int plotSceneEnd = itemRect.x() + itemRect.width() - horizontalPadding;
 	if (!hasValidBreak) {
 		//no breaks available -> range goes from the plot beginning to the end of the plot
 		sceneStart = plotSceneStart;
 		sceneEnd = plotSceneEnd;
 		logicalStart = xMin;
 		logicalEnd = xMax;
 
 		//TODO: how should we handle the case sceneStart == sceneEnd?
 		//(to reproduce, create plots and adjust the spacing/pading to get zero size for the plots)
 		if (sceneStart != sceneEnd)
 			scales << this->createScale(xScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	} else {
 		int sceneEndLast = plotSceneStart;
 		int logicalEndLast = xMin;
 		for (const auto& rb: xRangeBreaks.list) {
 			if (!rb.isValid())
 				break;
 
 			//current range goes from the end of the previous one (or from the plot beginning) to curBreak.start
 			sceneStart = sceneEndLast;
 			if (&rb == &xRangeBreaks.list.first()) sceneStart += breakGap;
 			sceneEnd = plotSceneStart + (plotSceneEnd-plotSceneStart) * rb.position;
 			logicalStart = logicalEndLast;
 			logicalEnd = rb.start;
 
 			if (sceneStart != sceneEnd)
 				scales << this->createScale(xScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 
 			sceneEndLast = sceneEnd;
 			logicalEndLast = rb.end;
 		}
 
 		//add the remaining range going from the last available range break to the end of the plot (=end of the x-data range)
 		sceneStart = sceneEndLast+breakGap;
 		sceneEnd = plotSceneEnd;
 		logicalStart = logicalEndLast;
 		logicalEnd = xMax;
 
 		if (sceneStart != sceneEnd)
 			scales << this->createScale(xScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	}
 
 	cSystem->setXScales(scales);
 
 	//check ranges for log-scales
 	if (yScale != CartesianPlot::ScaleLinear)
 		checkYRange();
 
 	//check whether we have y-range breaks - the first break, if available, should be valid
 	hasValidBreak = (yRangeBreakingEnabled && !yRangeBreaks.list.isEmpty() && yRangeBreaks.list.first().isValid());
 
 	//create y-scales
 	scales.clear();
 	plotSceneStart = itemRect.y()+itemRect.height()-verticalPadding;
 	plotSceneEnd = itemRect.y()+verticalPadding;
 	if (!hasValidBreak) {
 		//no breaks available -> range goes from the plot beginning to the end of the plot
 		sceneStart = plotSceneStart;
 		sceneEnd = plotSceneEnd;
 		logicalStart = yMin;
 		logicalEnd = yMax;
 
 		if (sceneStart != sceneEnd)
 			scales << this->createScale(yScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	} else {
 		int sceneEndLast = plotSceneStart;
 		int logicalEndLast = yMin;
 		for (const auto& rb: yRangeBreaks.list) {
 			if (!rb.isValid())
 				break;
 
 			//current range goes from the end of the previous one (or from the plot beginning) to curBreak.start
 			sceneStart = sceneEndLast;
 			if (&rb == &yRangeBreaks.list.first()) sceneStart -= breakGap;
 			sceneEnd = plotSceneStart + (plotSceneEnd-plotSceneStart) * rb.position;
 			logicalStart = logicalEndLast;
 			logicalEnd = rb.start;
 
 			if (sceneStart != sceneEnd)
 				scales << this->createScale(yScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 
 			sceneEndLast = sceneEnd;
 			logicalEndLast = rb.end;
 		}
 
 		//add the remaining range going from the last available range break to the end of the plot (=end of the y-data range)
 		sceneStart = sceneEndLast-breakGap;
 		sceneEnd = plotSceneEnd;
 		logicalStart = logicalEndLast;
 		logicalEnd = yMax;
 
 		if (sceneStart != sceneEnd)
 			scales << this->createScale(yScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	}
 
 	cSystem->setYScales(scales);
 
 	//calculate the changes in x and y and save the current values for xMin, xMax, yMin, yMax
 	double deltaXMin = 0;
 	double deltaXMax = 0;
 	double deltaYMin = 0;
 	double deltaYMax = 0;
 
 	if (xMin != xMinPrev) {
 		deltaXMin = xMin - xMinPrev;
 		emit plot->xMinChanged(xMin);
 	}
 
 	if (xMax != xMaxPrev) {
 		deltaXMax = xMax - xMaxPrev;
 		emit plot->xMaxChanged(xMax);
 	}
 
 	if (yMin != yMinPrev) {
 		deltaYMin = yMin - yMinPrev;
 		emit plot->yMinChanged(yMin);
 	}
 
 	if (yMax!=yMaxPrev) {
 		deltaYMax = yMax - yMaxPrev;
 		emit plot->yMaxChanged(yMax);
 	}
 
 	xMinPrev = xMin;
 	xMaxPrev = xMax;
 	yMinPrev = yMin;
 	yMaxPrev = yMax;
 	//adjust auto-scale axes
 	for (auto* axis: q->children<Axis>()) {
 		if (!axis->autoScale())
 			continue;
 
 		if (axis->orientation() == Axis::AxisHorizontal) {
 			if (deltaXMax != 0) {
 				axis->setUndoAware(false);
 				axis->setSuppressRetransform(true);
 				axis->setEnd(xMax);
 				axis->setUndoAware(true);
 				axis->setSuppressRetransform(false);
 			}
 			if (deltaXMin != 0) {
 				axis->setUndoAware(false);
 				axis->setSuppressRetransform(true);
 				axis->setStart(xMin);
 				axis->setUndoAware(true);
 				axis->setSuppressRetransform(false);
 			}
 			//TODO;
 // 			if (axis->position() == Axis::AxisCustom && deltaYMin != 0) {
 // 				axis->setOffset(axis->offset() + deltaYMin, false);
 // 			}
 		} else {
 			if (deltaYMax != 0) {
 				axis->setUndoAware(false);
 				axis->setSuppressRetransform(true);
 				axis->setEnd(yMax);
 				axis->setUndoAware(true);
 				axis->setSuppressRetransform(false);
 			}
 			if (deltaYMin != 0) {
 				axis->setUndoAware(false);
 				axis->setSuppressRetransform(true);
 				axis->setStart(yMin);
 				axis->setUndoAware(true);
 				axis->setSuppressRetransform(false);
 			}
 
 			//TODO;
 // 			if (axis->position() == Axis::AxisCustom && deltaXMin != 0) {
 // 				axis->setOffset(axis->offset() + deltaXMin, false);
 // 			}
 		}
 	}
 	// call retransform() on the parent to trigger the update of all axes and curvesю
 	//no need to do this on load since all plots are retransformed again after the project is loaded.
 	if (!q->isLoading())
 		q->retransform();
 }
 
 /*
  * calculates the rectangular of the are showing the actual data (plot's rect minus padding),
  * in plot's coordinates.
  */
 void CartesianPlotPrivate::updateDataRect() {
 	dataRect = mapRectFromScene(rect);
 	dataRect.setX(dataRect.x() + horizontalPadding);
 	dataRect.setY(dataRect.y() + verticalPadding);
 	dataRect.setWidth(dataRect.width() - horizontalPadding);
 	dataRect.setHeight(dataRect.height() - verticalPadding);
 }
 
 void CartesianPlotPrivate::rangeChanged() {
 	curvesXMinMaxIsDirty = true;
 	curvesYMinMaxIsDirty = true;
 	if (autoScaleX && autoScaleY)
 		q->scaleAuto();
 	else if (autoScaleX)
 		q->scaleAutoX();
 	else if (autoScaleY)
 		q->scaleAutoY();
 }
 
 /*!
  * don't allow any negative values for the x range when log or sqrt scalings are used
  */
 void CartesianPlotPrivate::checkXRange() {
 	double min = 0.01;
 
 	if (xMin <= 0.0) {
 		(min < xMax*min) ? xMin = min : xMin = xMax*min;
 		emit q->xMinChanged(xMin);
 	} else if (xMax <= 0.0) {
 		(-min > xMin*min) ? xMax = -min : xMax = xMin*min;
 		emit q->xMaxChanged(xMax);
 	}
 }
 
 /*!
  * don't allow any negative values for the y range when log or sqrt scalings are used
  */
 void CartesianPlotPrivate::checkYRange() {
 	double min = 0.01;
 
 	if (yMin <= 0.0) {
 		(min < yMax*min) ? yMin = min : yMin = yMax*min;
 		emit q->yMinChanged(yMin);
 	} else if (yMax <= 0.0) {
 		(-min > yMin*min) ? yMax = -min : yMax = yMin*min;
 		emit q->yMaxChanged(yMax);
 	}
 }
 
 CartesianScale* CartesianPlotPrivate::createScale(CartesianPlot::Scale type, double sceneStart, double sceneEnd, double logicalStart, double logicalEnd) {
 	DEBUG("CartesianPlotPrivate::createScale() scence start/end = " << sceneStart << '/' << sceneEnd << ", logical start/end = " << logicalStart << '/' << logicalEnd);
 // 	Interval<double> interval (logicalStart-0.01, logicalEnd+0.01); //TODO: move this to CartesianScale
 	Interval<double> interval (std::numeric_limits<double>::lowest(), std::numeric_limits<double>::max());
 // 	Interval<double> interval (logicalStart, logicalEnd);
 	if (type == CartesianPlot::ScaleLinear)
 		return CartesianScale::createLinearScale(interval, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	else {
 		double base;
 		if (type == CartesianPlot::ScaleLog10)
 			base = 10.0;
 		else if (type == CartesianPlot::ScaleLog2)
 			base = 2.0;
 		else
 			base = M_E;
 
 		return CartesianScale::createLogScale(interval, sceneStart, sceneEnd, logicalStart, logicalEnd, base);
 	}
 }
 
 /*!
  * Reimplemented from QGraphicsItem.
  */
 QVariant CartesianPlotPrivate::itemChange(GraphicsItemChange change, const QVariant &value) {
 	if (change == QGraphicsItem::ItemPositionChange) {
 		const QPointF& itemPos = value.toPointF();//item's center point in parent's coordinates;
 		const qreal x = itemPos.x();
 		const qreal y = itemPos.y();
 
 		//calculate the new rect and forward the changes to the frontend
 		QRectF newRect;
 		const qreal w = rect.width();
 		const qreal h = rect.height();
 		newRect.setX(x-w/2);
 		newRect.setY(y-h/2);
 		newRect.setWidth(w);
 		newRect.setHeight(h);
 		emit q->rectChanged(newRect);
 	}
 	return QGraphicsItem::itemChange(change, value);
 }
 
 //##############################################################################
 //##################################  Events  ##################################
 //##############################################################################
 void CartesianPlotPrivate::mousePressEvent(QGraphicsSceneMouseEvent *event) {
 	if (mouseMode == CartesianPlot::ZoomSelectionMode || mouseMode == CartesianPlot::ZoomXSelectionMode || mouseMode == CartesianPlot::ZoomYSelectionMode) {
 
 		if (mouseMode == CartesianPlot::ZoomSelectionMode)
 			m_selectionStart = event->pos();
 		else if (mouseMode == CartesianPlot::ZoomXSelectionMode) {
 			m_selectionStart.setX(event->pos().x());
 			m_selectionStart.setY(dataRect.height()/2);
 		} else if (mouseMode == CartesianPlot::ZoomYSelectionMode) {
 			m_selectionStart.setX(-dataRect.width()/2);
 			m_selectionStart.setY(event->pos().y());
 		}
 
 		m_selectionEnd = m_selectionStart;
 		m_selectionBandIsShown = true;
 	} else {
 		if ( dataRect.contains(event->pos()) ){
-			m_panningStarted = true;
+			panningStarted = true;
 			m_panningStart = event->pos();
 			setCursor(Qt::ClosedHandCursor);
 		}
 		QGraphicsItem::mousePressEvent(event);
 	}
 }
 
 void CartesianPlotPrivate::mouseMoveEvent(QGraphicsSceneMouseEvent* event) {
 	if (mouseMode == CartesianPlot::SelectionMode) {
-		if (m_panningStarted && dataRect.contains(event->pos()) ) {
+		if (panningStarted && dataRect.contains(event->pos()) ) {
 			//don't retransform on small mouse movement deltas
 			const int deltaXScene = (m_panningStart.x() - event->pos().x());
 			const int deltaYScene = (m_panningStart.y() - event->pos().y());
 			if (abs(deltaXScene) < 5 && abs(deltaYScene) < 5)
 				return;
 
 			const QPointF logicalEnd = cSystem->mapSceneToLogical(event->pos());
 			const QPointF logicalStart = cSystem->mapSceneToLogical(m_panningStart);
 			const float deltaX = (logicalStart.x() - logicalEnd.x());
 			const float deltaY = (logicalStart.y() - logicalEnd.y());
 			xMax += deltaX;
 			xMin += deltaX;
 			yMax += deltaY;
 			yMin += deltaY;
 			retransformScales();
 			m_panningStart = event->pos();
 		} else
 			QGraphicsItem::mouseMoveEvent(event);
 	} else if (mouseMode == CartesianPlot::ZoomSelectionMode || mouseMode == CartesianPlot::ZoomXSelectionMode || mouseMode == CartesianPlot::ZoomYSelectionMode) {
 		QGraphicsItem::mouseMoveEvent(event);
 		if ( !boundingRect().contains(event->pos()) ) {
 			q->info("");
 			return;
 		}
 
 		QString info;
 		QPointF logicalStart = cSystem->mapSceneToLogical(m_selectionStart);
 		if (mouseMode == CartesianPlot::ZoomSelectionMode) {
 			m_selectionEnd = event->pos();
 			QPointF logicalEnd = cSystem->mapSceneToLogical(m_selectionEnd);
 			info = QString::fromUtf8("Δx=") + QString::number(logicalEnd.x()-logicalStart.x()) + QString::fromUtf8(", Δy=") + QString::number(logicalEnd.y()-logicalStart.y());
 		} else if (mouseMode == CartesianPlot::ZoomXSelectionMode) {
 			m_selectionEnd.setX(event->pos().x());
 			m_selectionEnd.setY(-dataRect.height()/2);
 			QPointF logicalEnd = cSystem->mapSceneToLogical(m_selectionEnd);
 			info = QString::fromUtf8("Δx=") + QString::number(logicalEnd.x()-logicalStart.x());
 		} else if (mouseMode == CartesianPlot::ZoomYSelectionMode) {
 			m_selectionEnd.setX(dataRect.width()/2);
 			m_selectionEnd.setY(event->pos().y());
 			QPointF logicalEnd = cSystem->mapSceneToLogical(m_selectionEnd);
 			info = QString::fromUtf8("Δy=") + QString::number(logicalEnd.y()-logicalStart.y());
 		}
 		q->info(info);
 		update();
 	}
 }
 
 void CartesianPlotPrivate::mouseReleaseEvent(QGraphicsSceneMouseEvent* event) {
 	setCursor(Qt::ArrowCursor);
 	if (mouseMode == CartesianPlot::SelectionMode) {
-		m_panningStarted = false;
+		panningStarted = false;
 
 		//TODO: why do we do this all the time?!?!
 		const QPointF& itemPos = pos();//item's center point in parent's coordinates;
 		const qreal x = itemPos.x();
 		const qreal y = itemPos.y();
 
 		//calculate the new rect and set it
 		QRectF newRect;
 		const qreal w = rect.width();
 		const qreal h = rect.height();
 		newRect.setX(x-w/2);
 		newRect.setY(y-h/2);
 		newRect.setWidth(w);
 		newRect.setHeight(h);
 
 		suppressRetransform = true;
 		q->setRect(newRect);
 		suppressRetransform = false;
 
 		QGraphicsItem::mouseReleaseEvent(event);
 	} else if (mouseMode == CartesianPlot::ZoomSelectionMode || mouseMode == CartesianPlot::ZoomXSelectionMode || mouseMode == CartesianPlot::ZoomYSelectionMode) {
 		//don't zoom if very small region was selected, avoid occasional/unwanted zooming
 		if ( qAbs(m_selectionEnd.x()-m_selectionStart.x()) < 20 || qAbs(m_selectionEnd.y()-m_selectionStart.y()) < 20 ) {
 			m_selectionBandIsShown = false;
 			return;
 		}
 
 		//determine the new plot ranges
 		QPointF logicalZoomStart = cSystem->mapSceneToLogical(m_selectionStart, AbstractCoordinateSystem::SuppressPageClipping);
 		QPointF logicalZoomEnd = cSystem->mapSceneToLogical(m_selectionEnd, AbstractCoordinateSystem::SuppressPageClipping);
 		if (m_selectionEnd.x() > m_selectionStart.x()) {
 			xMin = logicalZoomStart.x();
 			xMax = logicalZoomEnd.x();
 		} else {
 			xMin = logicalZoomEnd.x();
 			xMax = logicalZoomStart.x();
 		}
 
 		if (m_selectionEnd.y() > m_selectionStart.y()) {
 			yMin = logicalZoomEnd.y();
 			yMax = logicalZoomStart.y();
 		} else {
 			yMin = logicalZoomStart.y();
 			yMax = logicalZoomEnd.y();
 		}
 
 		m_selectionBandIsShown = false;
 		retransformScales();
 	}
 }
 
 void CartesianPlotPrivate::wheelEvent(QGraphicsSceneWheelEvent* event) {
 	//determine first, which axes are selected and zoom only in the corresponding direction.
 	//zoom the entire plot if no axes selected.
 	bool zoomX = false;
 	bool zoomY = false;
 	for (auto* axis: q->children<Axis>()) {
 		if (!axis->graphicsItem()->isSelected())
 			continue;
 
 		if (axis->orientation() == Axis::AxisHorizontal)
 			zoomX  = true;
 		else
 			zoomY = true;
 	}
 
 	if (event->delta() > 0) {
 		if (!zoomX && !zoomY) {
 			//no special axis selected -> zoom in everything
 			q->zoomIn();
 		} else {
 			if (zoomX) q->zoomInX();
 			if (zoomY) q->zoomInY();
 		}
 	} else {
 		if (!zoomX && !zoomY) {
 			//no special axis selected -> zoom in everything
 			q->zoomOut();
 		} else {
 			if (zoomX) q->zoomOutX();
 			if (zoomY) q->zoomOutY();
 		}
 	}
 }
 
 void CartesianPlotPrivate::hoverMoveEvent(QGraphicsSceneHoverEvent* event) {
 	QPointF point = event->pos();
 	QString info;
 	if (dataRect.contains(point)) {
 		QPointF logicalPoint = cSystem->mapSceneToLogical(point);
 		if (mouseMode == CartesianPlot::ZoomSelectionMode && !m_selectionBandIsShown)
 			info = "x=" + QString::number(logicalPoint.x()) + ", y=" + QString::number(logicalPoint.y());
 		else if (mouseMode == CartesianPlot::ZoomXSelectionMode && !m_selectionBandIsShown) {
 			QPointF p1(logicalPoint.x(), yMin);
 			QPointF p2(logicalPoint.x(), yMax);
 			m_selectionStartLine.setP1(cSystem->mapLogicalToScene(p1));
 			m_selectionStartLine.setP2(cSystem->mapLogicalToScene(p2));
 			info = "x=" + QString::number(logicalPoint.x());
 			update();
 		} else if (mouseMode == CartesianPlot::ZoomYSelectionMode && !m_selectionBandIsShown) {
 			QPointF p1(xMin, logicalPoint.y());
 			QPointF p2(xMax, logicalPoint.y());
 			m_selectionStartLine.setP1(cSystem->mapLogicalToScene(p1));
 			m_selectionStartLine.setP2(cSystem->mapLogicalToScene(p2));
 			info = "y=" + QString::number(logicalPoint.y());
 			update();
 		}
 	}
 	q->info(info);
 
 	QGraphicsItem::hoverMoveEvent(event);
 }
 
 void CartesianPlotPrivate::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget * widget) {
 	if (!isVisible())
 		return;
 
 	painter->setPen(QPen(Qt::black, 3));
 	if ((mouseMode == CartesianPlot::ZoomXSelectionMode || mouseMode == CartesianPlot::ZoomYSelectionMode)
 	        && (!m_selectionBandIsShown))
 		painter->drawLine(m_selectionStartLine);
 
 	if (m_selectionBandIsShown) {
 		painter->save();
 		painter->setPen(QPen(Qt::black, 5));
 		painter->drawRect(QRectF(m_selectionStart, m_selectionEnd));
 		painter->setBrush(Qt::blue);
 		painter->setOpacity(0.2);
 		painter->drawRect(QRectF(m_selectionStart, m_selectionEnd));
 		painter->restore();
 	}
 
 	WorksheetElementContainerPrivate::paint(painter, option, widget);
 }
 
 //##############################################################################
 //##################  Serialization/Deserialization  ###########################
 //##############################################################################
 
 //! Save as XML
 void CartesianPlot::save(QXmlStreamWriter* writer) const {
 	Q_D(const CartesianPlot);
 
 	writer->writeStartElement( "cartesianPlot" );
 	writeBasicAttributes(writer);
 	writeCommentElement(writer);
 
 	//applied theme
 	if (!d->theme.isEmpty()) {
 		writer->writeStartElement( "theme" );
 		writer->writeAttribute("name", d->theme);
 		writer->writeEndElement();
 	}
 
 	//geometry
 	writer->writeStartElement( "geometry" );
 	writer->writeAttribute( "x", QString::number(d->rect.x()) );
 	writer->writeAttribute( "y", QString::number(d->rect.y()) );
 	writer->writeAttribute( "width", QString::number(d->rect.width()) );
 	writer->writeAttribute( "height", QString::number(d->rect.height()) );
 	writer->writeAttribute( "visible", QString::number(d->isVisible()) );
 	writer->writeEndElement();
 
 	//coordinate system and padding
 	writer->writeStartElement( "coordinateSystem" );
 	writer->writeAttribute( "autoScaleX", QString::number(d->autoScaleX) );
 	writer->writeAttribute( "autoScaleY", QString::number(d->autoScaleY) );
 	writer->writeAttribute( "xMin", QString::number(d->xMin) );
 	writer->writeAttribute( "xMax", QString::number(d->xMax) );
 	writer->writeAttribute( "yMin", QString::number(d->yMin) );
 	writer->writeAttribute( "yMax", QString::number(d->yMax) );
 	writer->writeAttribute( "xScale", QString::number(d->xScale) );
 	writer->writeAttribute( "yScale", QString::number(d->yScale) );
 	writer->writeAttribute( "horizontalPadding", QString::number(d->horizontalPadding) );
 	writer->writeAttribute( "verticalPadding", QString::number(d->verticalPadding) );
 	writer->writeEndElement();
 
 	//x-scale breaks
 	if (d->xRangeBreakingEnabled || !d->xRangeBreaks.list.isEmpty()) {
 		writer->writeStartElement("xRangeBreaks");
 		writer->writeAttribute( "enabled", QString::number(d->xRangeBreakingEnabled) );
 		for (const auto& rb: d->xRangeBreaks.list) {
 			writer->writeStartElement("xRangeBreak");
 			writer->writeAttribute("start", QString::number(rb.start));
 			writer->writeAttribute("end", QString::number(rb.end));
 			writer->writeAttribute("position", QString::number(rb.position));
 			writer->writeAttribute("style", QString::number(rb.style));
 			writer->writeEndElement();
 		}
 		writer->writeEndElement();
 	}
 
 	//y-scale breaks
 	if (d->yRangeBreakingEnabled || !d->yRangeBreaks.list.isEmpty()) {
 		writer->writeStartElement("yRangeBreaks");
 		writer->writeAttribute( "enabled", QString::number(d->yRangeBreakingEnabled) );
 		for (const auto& rb: d->yRangeBreaks.list) {
 			writer->writeStartElement("yRangeBreak");
 			writer->writeAttribute("start", QString::number(rb.start));
 			writer->writeAttribute("end", QString::number(rb.end));
 			writer->writeAttribute("position", QString::number(rb.position));
 			writer->writeAttribute("style", QString::number(rb.style));
 			writer->writeEndElement();
 		}
 		writer->writeEndElement();
 	}
 
 	//serialize all children (plot area, title text label, axes and curves)
 	for (auto *elem: children<WorksheetElement>(IncludeHidden))
 		elem->save(writer);
 
 	writer->writeEndElement(); // close "cartesianPlot" section
 }
 
 
 //! Load from XML
 bool CartesianPlot::load(XmlStreamReader* reader, bool preview) {
 	Q_D(CartesianPlot);
 
 	if (!reader->isStartElement() || reader->name() != "cartesianPlot") {
 		reader->raiseError(i18n("no cartesianPlot element found"));
 		return false;
 	}
 
 	if (!readBasicAttributes(reader))
 		return false;
 
 	QString attributeWarning = i18n("Attribute '%1' missing or empty, default value is used");
 	QXmlStreamAttributes attribs;
 	QString str;
 
 	while (!reader->atEnd()) {
 		reader->readNext();
 		if (reader->isEndElement() && reader->name() == "cartesianPlot")
 			break;
 
 		if (!reader->isStartElement())
 			continue;
 
 		if (reader->name() == "comment") {
 			if (!readCommentElement(reader))
 				return false;
 		} else if (!preview && reader->name() == "theme") {
 			attribs = reader->attributes();
 			d->theme = attribs.value("name").toString();
 		} else if (!preview && reader->name() == "geometry") {
 			attribs = reader->attributes();
 
 			str = attribs.value("x").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'x'"));
 			else
 				d->rect.setX( str.toDouble() );
 
 			str = attribs.value("y").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'y'"));
 			else
 				d->rect.setY( str.toDouble() );
 
 			str = attribs.value("width").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'width'"));
 			else
 				d->rect.setWidth( str.toDouble() );
 
 			str = attribs.value("height").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'height'"));
 			else
 				d->rect.setHeight( str.toDouble() );
 
 			str = attribs.value("visible").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'visible'"));
 			else
 				d->setVisible(str.toInt());
 		} else if (!preview && reader->name() == "coordinateSystem") {
 			attribs = reader->attributes();
 
 			str = attribs.value("autoScaleX").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'autoScaleX'"));
 			else
 				d->autoScaleX = bool(str.toInt());
 
 			str = attribs.value("autoScaleY").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'autoScaleY'"));
 			else
 				d->autoScaleY = bool(str.toInt());
 
 			str = attribs.value("xMin").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'xMin'"));
 			else {
 				d->xMin = str.toDouble();
 				d->xMinPrev = d->xMin;
 			}
 
 			str = attribs.value("xMax").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'xMax'"));
 			else {
 				d->xMax = str.toDouble();
 				d->xMaxPrev = d->xMax;
 			}
 
 			str = attribs.value("yMin").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'yMin'"));
 			else {
 				d->yMin = str.toDouble();
 				d->yMinPrev = d->yMin;
 			}
 
 			str = attribs.value("yMax").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'yMax'"));
 			else {
 				d->yMax = str.toDouble();
 				d->yMaxPrev = d->yMax;
 			}
 
 			str = attribs.value("xScale").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'xScale'"));
 			else
 				d->xScale = CartesianPlot::Scale(str.toInt());
 
 			str = attribs.value("yScale").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'yScale'"));
 			else
 				d->yScale = CartesianPlot::Scale(str.toInt());
 
 			str = attribs.value("horizontalPadding").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'horizontalPadding'"));
 			else
 				d->horizontalPadding = str.toDouble();
 
 			str = attribs.value("verticalPadding").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'verticalPadding'"));
 			else
 				d->verticalPadding = str.toDouble();
 		} else if (!preview && reader->name() == "xRangeBreaks") {
 			//delete default rang break
 			d->xRangeBreaks.list.clear();
 
 			attribs = reader->attributes();
 			str = attribs.value("enabled").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'enabled'"));
 			else
 				d->xRangeBreakingEnabled = str.toInt();
 		} else if (!preview && reader->name() == "xRangeBreak") {
 			attribs = reader->attributes();
 
 			RangeBreak b;
 			str = attribs.value("start").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'start'"));
 			else
 				b.start = str.toDouble();
 
 			str = attribs.value("end").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'end'"));
 			else
 				b.end = str.toDouble();
 
 			str = attribs.value("position").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'position'"));
 			else
 				b.position = str.toDouble();
 
 			str = attribs.value("style").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'style'"));
 			else
 				b.style = CartesianPlot::RangeBreakStyle(str.toInt());
 
 			d->xRangeBreaks.list << b;
 		} else if (!preview && reader->name() == "yRangeBreaks") {
 			//delete default rang break
 			d->yRangeBreaks.list.clear();
 
 			attribs = reader->attributes();
 			str = attribs.value("enabled").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'enabled'"));
 			else
 				d->yRangeBreakingEnabled = str.toInt();
 		} else if (!preview && reader->name() == "yRangeBreak") {
 			attribs = reader->attributes();
 
 			RangeBreak b;
 			str = attribs.value("start").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'start'"));
 			else
 				b.start = str.toDouble();
 
 			str = attribs.value("end").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'end'"));
 			else
 				b.end = str.toDouble();
 
 			str = attribs.value("position").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'position'"));
 			else
 				b.position = str.toDouble();
 
 			str = attribs.value("style").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'style'"));
 			else
 				b.style = CartesianPlot::RangeBreakStyle(str.toInt());
 
 			d->yRangeBreaks.list << b;
 		} else if (reader->name() == "textLabel") {
 			m_title = new TextLabel("");
 			if (m_title->load(reader, preview))
 				addChildFast(m_title);
 			else {
 				delete m_title;
 				m_title=0;
 				return false;
 			}
 		} else if (reader->name() == "plotArea")
 			m_plotArea->load(reader, preview);
 		else if (reader->name() == "axis") {
 			Axis* axis = new Axis("");
 			if (axis->load(reader, preview))
 				addChildFast(axis);
 			else {
 				delete axis;
 				return false;
 			}
 		} else if (reader->name() == "xyCurve") {
 			XYCurve* curve = new XYCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyEquationCurve") {
 			XYEquationCurve* curve = new XYEquationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyDataReductionCurve") {
 			XYDataReductionCurve* curve = new XYDataReductionCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyDifferentiationCurve") {
 			XYDifferentiationCurve* curve = new XYDifferentiationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyIntegrationCurve") {
 			XYIntegrationCurve* curve = new XYIntegrationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyInterpolationCurve") {
 			XYInterpolationCurve* curve = new XYInterpolationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyFitCurve") {
 			XYFitCurve* curve = new XYFitCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyFourierFilterCurve") {
 			XYFourierFilterCurve* curve = new XYFourierFilterCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyFourierTransformCurve") {
 			XYFourierTransformCurve* curve = new XYFourierTransformCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xySmoothCurve") {
 			XYSmoothCurve* curve = new XYSmoothCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "cartesianPlotLegend") {
 			m_legend = new CartesianPlotLegend(this, "");
 			if (m_legend->load(reader, preview))
 				addChildFast(m_legend);
 			else {
 				delete m_legend;
 				return false;
 			}
 		} else if (reader->name() == "customPoint") {
 			CustomPoint* point = new CustomPoint(this, "");
 			if (point->load(reader, preview))
 				addChildFast(point);
 			else {
 				delete point;
 				return false;
 			}
 		} else if(reader->name() == "Histogram") {
 			Histogram* curve = new Histogram("Histogram");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else { // unknown element
 			reader->raiseWarning(i18n("unknown cartesianPlot element '%1'", reader->name().toString()));
 			if (!reader->skipToEndElement()) return false;
 		}
 	}
 
 	if (preview)
 		return true;
 
 	d->retransform();
 
 	if (m_title) {
 		m_title->setHidden(true);
 		m_title->graphicsItem()->setParentItem(m_plotArea->graphicsItem());
 	}
 
 	//if a theme was used, initialize the color palette
 	if (!d->theme.isEmpty()) {
 		//TODO: check whether the theme config really exists
 		KConfig config( ThemeHandler::themeFilePath(d->theme), KConfig::SimpleConfig );
 		this->setColorPalette(config);
 	}
 
 	return true;
 }
 
 //##############################################################################
 //#########################  Theme management ##################################
 //##############################################################################
 void CartesianPlot::loadTheme(const QString& theme) {
 	KConfig config(ThemeHandler::themeFilePath(theme), KConfig::SimpleConfig);
 	loadThemeConfig(config);
 }
 
 void CartesianPlot::loadThemeConfig(const KConfig& config) {
 	QString str = config.name();
 	str = str.right(str.length() - str.lastIndexOf(QDir::separator()) - 1);
 	this->setTheme(str);
 
 	//load the color palettes for the curves
 	this->setColorPalette(config);
 
 	//load the theme for all the children
 	for (auto* child: children<WorksheetElement>(AbstractAspect::IncludeHidden))
 		child->loadThemeConfig(config);
 
 	Q_D(CartesianPlot);
 	d->update(this->rect());
 }
 
 void CartesianPlot::saveTheme(KConfig &config) {
 	const QVector<Axis*>& axisElements = children<Axis>(AbstractAspect::IncludeHidden);
 	const QVector<PlotArea*>& plotAreaElements = children<PlotArea>(AbstractAspect::IncludeHidden);
 	const QVector<TextLabel*>& textLabelElements = children<TextLabel>(AbstractAspect::IncludeHidden);
 
 	axisElements.at(0)->saveThemeConfig(config);
 	plotAreaElements.at(0)->saveThemeConfig(config);
 	textLabelElements.at(0)->saveThemeConfig(config);
 
 	for (auto *child: children<XYCurve>(AbstractAspect::IncludeHidden))
 		child->saveThemeConfig(config);
 }
 
 //Generating colors from 5-color theme palette
 void CartesianPlot::setColorPalette(const KConfig& config) {
 	KConfigGroup group = config.group("Theme");
 
 	//read the five colors defining the palette
 	m_themeColorPalette.clear();
 	m_themeColorPalette.append(group.readEntry("ThemePaletteColor1", QColor()));
 	m_themeColorPalette.append(group.readEntry("ThemePaletteColor2", QColor()));
 	m_themeColorPalette.append(group.readEntry("ThemePaletteColor3", QColor()));
 	m_themeColorPalette.append(group.readEntry("ThemePaletteColor4", QColor()));
 	m_themeColorPalette.append(group.readEntry("ThemePaletteColor5", QColor()));
 
 	//generate 30 additional shades if the color palette contains more than one color
 	if (m_themeColorPalette.at(0) != m_themeColorPalette.at(1)) {
 		QColor c;
 
 		//3 factors to create shades from theme's palette
 		float fac[3] = {0.25f,0.45f,0.65f};
 
 		//Generate 15 lighter shades
 		for (int i = 0; i < 5; i++) {
 			for (int j = 1; j < 4; j++) {
 				c.setRed( m_themeColorPalette.at(i).red()*(1-fac[j-1]) );
 				c.setGreen( m_themeColorPalette.at(i).green()*(1-fac[j-1]) );
 				c.setBlue( m_themeColorPalette.at(i).blue()*(1-fac[j-1]) );
 				m_themeColorPalette.append(c);
 			}
 		}
 
 		//Generate 15 darker shades
 		for (int i = 0; i < 5; i++) {
 			for (int j = 4; j < 7; j++) {
 				c.setRed( m_themeColorPalette.at(i).red()+((255-m_themeColorPalette.at(i).red())*fac[j-4]) );
 				c.setGreen( m_themeColorPalette.at(i).green()+((255-m_themeColorPalette.at(i).green())*fac[j-4]) );
 				c.setBlue( m_themeColorPalette.at(i).blue()+((255-m_themeColorPalette.at(i).blue())*fac[j-4]) );
 				m_themeColorPalette.append(c);
 			}
 		}
 	}
 }
 
 const QList<QColor>& CartesianPlot::themeColorPalette() const {
 	return m_themeColorPalette;
 }
diff --git a/src/backend/worksheet/plots/cartesian/CartesianPlot.h b/src/backend/worksheet/plots/cartesian/CartesianPlot.h
index 9bc80d22f..1fcc4ef99 100644
--- a/src/backend/worksheet/plots/cartesian/CartesianPlot.h
+++ b/src/backend/worksheet/plots/cartesian/CartesianPlot.h
@@ -1,284 +1,285 @@
 
 /***************************************************************************
     File                 : CartesianPlot.h
     Project              : LabPlot
     Description          : Cartesian plot
     --------------------------------------------------------------------
     Copyright            : (C) 2011-2017 by Alexander Semke (alexander.semke@web.de)
 
  ***************************************************************************/
 
 /***************************************************************************
  *                                                                         *
  *  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.                                    *
  *                                                                         *
  *  This program is distributed in the hope that it will be useful,        *
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of         *
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
  *  GNU General Public License for more details.                           *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program; if not, write to the Free Software           *
  *   Foundation, Inc., 51 Franklin Street, Fifth Floor,                    *
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
 
 #ifndef CARTESIANPLOT_H
 #define CARTESIANPLOT_H
 
 #include "backend/worksheet/plots/AbstractPlot.h"
 #include "backend/worksheet/plots/cartesian/Histogram.h"
 
 #include <math.h>
 
 class QDropEvent;
 class QToolBar;
 class CartesianPlotPrivate;
 class CartesianPlotLegend;
 class AbstractColumn;
 class XYCurve;
 class XYEquationCurve;
 class XYDataReductionCurve;
 class XYDifferentiationCurve;
 class XYIntegrationCurve;
 class XYInterpolationCurve;
 class XYSmoothCurve;
 class XYFitCurve;
 class XYFourierFilterCurve;
 class KConfig;
 class XYFourierTransformCurve;
 
 class CartesianPlot:public AbstractPlot {
 	Q_OBJECT
 
 public:
 	explicit CartesianPlot(const QString &name);
 	~CartesianPlot() override;
 
 	enum Scale {ScaleLinear, ScaleLog10, ScaleLog2, ScaleLn, ScaleSqrt, ScaleX2};
 	enum Type {FourAxes, TwoAxes, TwoAxesCentered, TwoAxesCenteredZero};
 	enum RangeType {RangeFree, RangeLast, RangeFirst};
 	enum RangeBreakStyle {RangeBreakSimple, RangeBreakVertical, RangeBreakSloped};
 	enum MouseMode {SelectionMode, ZoomSelectionMode, ZoomXSelectionMode, ZoomYSelectionMode};
 	enum NavigationOperation {ScaleAuto, ScaleAutoX, ScaleAutoY, ZoomIn, ZoomOut, ZoomInX, ZoomOutX,
 	                          ZoomInY, ZoomOutY, ShiftLeftX, ShiftRightX, ShiftUpY, ShiftDownY
 	                         };
 
 	struct RangeBreak {
 		RangeBreak() : start(NAN), end(NAN), position(0.5), style(RangeBreakSloped) {}
 		bool isValid() const {
 			return (!std::isnan(start) && !std::isnan(end));
 		}
 		double start;
 		double end;
 		double position;
 		RangeBreakStyle style;
 	};
 
 	//simple wrapper for QList<RangeBreaking> in order to get our macros working
 	struct RangeBreaks {
 		RangeBreaks() : lastChanged(-1) {
 			RangeBreak b;
 			list << b;
 		};
 		QList<RangeBreak> list;
 		int lastChanged;
 	};
 
 	void initDefault(Type = FourAxes);
 	QIcon icon() const override;
 	QMenu* createContextMenu() override;
 	QMenu* analysisMenu();
 	QVector<AbstractAspect*> dependsOn() const override;
 	void setRect(const QRectF&) override;
 	QRectF dataRect() const;
 	void setMouseMode(const MouseMode);
 	MouseMode mouseMode() const;
 	void navigate(NavigationOperation);
 	void setSuppressDataChangedSignal(bool);
 	const QList<QColor>& themeColorPalette() const;
 	void processDropEvent(QDropEvent*);
+	bool isPanningActive() const;
 
 	void save(QXmlStreamWriter*) const override;
 	bool load(XmlStreamReader*, bool preview) override;
 	void loadThemeConfig(const KConfig&) override;
 	void saveTheme(KConfig& config);
 
 	BASIC_D_ACCESSOR_DECL(CartesianPlot::RangeType, rangeType, RangeType)
 	BASIC_D_ACCESSOR_DECL(int, rangeLastValues, RangeLastValues)
 	BASIC_D_ACCESSOR_DECL(int, rangeFirstValues, RangeFirstValues)
 	BASIC_D_ACCESSOR_DECL(bool, autoScaleX, AutoScaleX)
 	BASIC_D_ACCESSOR_DECL(bool, autoScaleY, AutoScaleY)
 	BASIC_D_ACCESSOR_DECL(double, xMin, XMin)
 	BASIC_D_ACCESSOR_DECL(double, xMax, XMax)
 	BASIC_D_ACCESSOR_DECL(double, yMin, YMin)
 	BASIC_D_ACCESSOR_DECL(double, yMax, YMax)
 	BASIC_D_ACCESSOR_DECL(CartesianPlot::Scale, xScale, XScale)
 	BASIC_D_ACCESSOR_DECL(CartesianPlot::Scale, yScale, YScale)
 	BASIC_D_ACCESSOR_DECL(bool, xRangeBreakingEnabled, XRangeBreakingEnabled)
 	BASIC_D_ACCESSOR_DECL(bool, yRangeBreakingEnabled, YRangeBreakingEnabled)
 	CLASS_D_ACCESSOR_DECL(RangeBreaks, xRangeBreaks, XRangeBreaks)
 	CLASS_D_ACCESSOR_DECL(RangeBreaks, yRangeBreaks, YRangeBreaks)
 
 	QString theme() const;
 
 	typedef CartesianPlotPrivate Private;
 
 public slots:
 	void setTheme(const QString&);
 
 private:
 	void init();
 	void initActions();
 	void initMenus();
 	void setColorPalette(const KConfig&);
 	const XYCurve* currentCurve() const;
 
 	CartesianPlotLegend* m_legend;
 	double m_zoomFactor;
 	QList<QColor> m_themeColorPalette;
 	bool m_menusInitialized;
 
 	QAction* visibilityAction;
 
 	//"add new" actions
 	QAction* addCurveAction;
 	QAction* addEquationCurveAction;
 	QAction* addHistogramPlot;
 	QAction* addDataReductionCurveAction;
 	QAction* addDifferentiationCurveAction;
 	QAction* addIntegrationCurveAction;
 	QAction* addInterpolationCurveAction;
 	QAction* addSmoothCurveAction;
 	QAction* addFitCurveAction;
 	QAction* addFourierFilterCurveAction;
 	QAction* addFourierTransformCurveAction;
 	QAction* addHorizontalAxisAction;
 	QAction* addVerticalAxisAction;
 	QAction* addLegendAction;
 	QAction* addCustomPointAction;
 
 	//scaling, zooming, navigation actions
 	QAction* scaleAutoXAction;
 	QAction* scaleAutoYAction;
 	QAction* scaleAutoAction;
 	QAction* zoomInAction;
 	QAction* zoomOutAction;
 	QAction* zoomInXAction;
 	QAction* zoomOutXAction;
 	QAction* zoomInYAction;
 	QAction* zoomOutYAction;
 	QAction* shiftLeftXAction;
 	QAction* shiftRightXAction;
 	QAction* shiftUpYAction;
 	QAction* shiftDownYAction;
 
 	//analysis menu actions
 	QAction* addDataOperationAction;
 	QAction* addDataReductionAction;
 	QAction* addDifferentiationAction;
 	QAction* addIntegrationAction;
 	QAction* addInterpolationAction;
 	QAction* addSmoothAction;
 	QVector <QAction *> addFitAction;
 	QAction* addFourierFilterAction;
 
 	QMenu* addNewMenu;
 	QMenu* zoomMenu;
 	QMenu* dataAnalysisMenu;
 	QMenu* themeMenu;
 
 	Q_DECLARE_PRIVATE(CartesianPlot)
 
 public slots:
 	void addHorizontalAxis();
 	void addVerticalAxis();
 	void addCurve();
 	void addHistogram();
 	void addEquationCurve();
 	void addDataReductionCurve();
 	void addDifferentiationCurve();
 	void addIntegrationCurve();
 	void addInterpolationCurve();
 	void addSmoothCurve();
 	void addFitCurve();
 	void addFourierFilterCurve();
 	void addFourierTransformCurve();
 	void addLegend();
 	void addCustomPoint();
 	void scaleAuto();
 	void scaleAutoX();
 	void scaleAutoY();
 	void zoomIn();
 	void zoomOut();
 	void zoomInX();
 	void zoomOutX();
 	void zoomInY();
 	void zoomOutY();
 	void shiftLeftX();
 	void shiftRightX();
 	void shiftUpY();
 	void shiftDownY();
 	void dataChanged();
 
 private slots:
 	void updateLegend();
 	void childAdded(const AbstractAspect*);
 	void childRemoved(const AbstractAspect* parent, const AbstractAspect* before, const AbstractAspect* child);
 
 	void xDataChanged();
 	void yDataChanged();
 	void HistogramdataChanged();
 	void xHistogramDataChanged();
 	void yHistogramDataChanged();
 	void curveVisibilityChanged();
 
 	//SLOTs for changes triggered via QActions in the context menu
 	void visibilityChanged();
 	void loadTheme(const QString&);
 
 protected:
 	CartesianPlot(const QString &name, CartesianPlotPrivate *dd);
 
 signals:
 	friend class CartesianPlotSetCRangeTypeCmd;
 	friend class CartesianPlotSetCRangeLastValuesCmd;
 	friend class CartesianPlotSetCRangeFirstValuesCmd;
 	friend class CartesianPlotSetRectCmd;
 	friend class CartesianPlotSetAutoScaleXCmd;
 	friend class CartesianPlotSetXMinCmd;
 	friend class CartesianPlotSetXMaxCmd;
 	friend class CartesianPlotSetXScaleCmd;
 	friend class CartesianPlotSetAutoScaleYCmd;
 	friend class CartesianPlotSetYMinCmd;
 	friend class CartesianPlotSetYMaxCmd;
 	friend class CartesianPlotSetYScaleCmd;
 	friend class CartesianPlotSetXRangeBreakingEnabledCmd;
 	friend class CartesianPlotSetYRangeBreakingEnabledCmd;
 	friend class CartesianPlotSetXRangeBreaksCmd;
 	friend class CartesianPlotSetYRangeBreaksCmd;
 	friend class CartesianPlotSetThemeCmd;
 	void rangeTypeChanged(CartesianPlot::RangeType);
 	void rangeLastValuesChanged(int);
 	void rangeFirstValuesChanged(int);
 	void rectChanged(QRectF&);
 	void xAutoScaleChanged(bool);
 	void xMinChanged(double);
 	void xMaxChanged(double);
 	void xScaleChanged(int);
 	void yAutoScaleChanged(bool);
 	void yMinChanged(double);
 	void yMaxChanged(double);
 	void yScaleChanged(int);
 	void xRangeBreakingEnabledChanged(bool);
 	void xRangeBreaksChanged(const CartesianPlot::RangeBreaks&);
 	void yRangeBreakingEnabledChanged(bool);
 	void yRangeBreaksChanged(const CartesianPlot::RangeBreaks&);
 	void themeChanged(const QString&);
 };
 
 #endif
diff --git a/src/backend/worksheet/plots/cartesian/CartesianPlotPrivate.h b/src/backend/worksheet/plots/cartesian/CartesianPlotPrivate.h
index f3444f513..513ce3349 100644
--- a/src/backend/worksheet/plots/cartesian/CartesianPlotPrivate.h
+++ b/src/backend/worksheet/plots/cartesian/CartesianPlotPrivate.h
@@ -1,95 +1,95 @@
 /***************************************************************************
     File                 : CartesianPlotPrivate.h
     Project              : LabPlot
     Description          : Private members of CartesianPlot.
     --------------------------------------------------------------------
     Copyright            : (C) 2014-2017 Alexander Semke (alexander.semke@web.de)
 
  *******************************************************7*******************/
 
 /***************************************************************************
  *                                                                         *
  *  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.                                    *
  *                                                                         *
  *  This program is distributed in the hope that it will be useful,        *
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of         *
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
  *  GNU General Public License for more details.                           *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program; if not, write to the Free Software           *
  *   Foundation, Inc., 51 Franklin Street, Fifth Floor,                    *
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
 
 #ifndef CARTESIANPLOTPRIVATE_H
 #define CARTESIANPLOTPRIVATE_H
 
 #include "CartesianPlot.h"
 #include "CartesianCoordinateSystem.h"
 #include "backend/worksheet/plots/AbstractPlotPrivate.h"
 
 #include <QGraphicsSceneMouseEvent>
 
 class CartesianPlotPrivate : public AbstractPlotPrivate {
 
 public:
 	explicit CartesianPlotPrivate(CartesianPlot*);
 
 	void retransform() override;
 	void retransformScales();
 	void rangeChanged();
 
 	QRectF dataRect;
 	CartesianPlot::RangeType rangeType;
 	int rangeFirstValues;
 	int rangeLastValues;
 	double xMin, xMax, yMin, yMax;
 	float xMinPrev, xMaxPrev, yMinPrev, yMaxPrev;
 	bool autoScaleX, autoScaleY;
 	float autoScaleOffsetFactor;
 	CartesianPlot::Scale xScale, yScale;
 	bool xRangeBreakingEnabled;
 	bool yRangeBreakingEnabled;
 	CartesianPlot::RangeBreaks xRangeBreaks;
 	CartesianPlot::RangeBreaks yRangeBreaks;
 	QString theme;
 
 	//cached values of minimum and maximum for all visible curves
 	bool curvesXMinMaxIsDirty, curvesYMinMaxIsDirty;
 	double curvesXMin, curvesXMax, curvesYMin, curvesYMax;
 
 	CartesianPlot* const q;
 	CartesianPlot::MouseMode mouseMode;
 	CartesianCoordinateSystem* cSystem;
 	bool suppressRetransform;
+	bool panningStarted;
 
 private:
 	QVariant itemChange(GraphicsItemChange change, const QVariant &value) override;
 	void mousePressEvent(QGraphicsSceneMouseEvent*) override;
 	void mouseReleaseEvent(QGraphicsSceneMouseEvent*) override;
 	void mouseMoveEvent(QGraphicsSceneMouseEvent*) override;
 	void wheelEvent(QGraphicsSceneWheelEvent*) override;
 	void hoverMoveEvent(QGraphicsSceneHoverEvent*) override;
 	void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget* widget = nullptr) override;
 
 	void updateDataRect();
 	void checkXRange();
 	void checkYRange();
 	CartesianScale* createScale(CartesianPlot::Scale type,
 		double sceneStart, double sceneEnd,
 		double logicalStart, double logicalEnd);
 
 	bool m_selectionBandIsShown;
 	QPointF m_selectionStart;
 	QPointF m_selectionEnd;
 	QLineF m_selectionStartLine;
-	bool m_panningStarted;
 	QPointF m_panningStart;
 };
 
 #endif
diff --git a/src/backend/worksheet/plots/cartesian/XYCurve.cpp b/src/backend/worksheet/plots/cartesian/XYCurve.cpp
index 350efda40..03e102f41 100644
--- a/src/backend/worksheet/plots/cartesian/XYCurve.cpp
+++ b/src/backend/worksheet/plots/cartesian/XYCurve.cpp
@@ -1,2452 +1,2454 @@
 /***************************************************************************
     File                 : XYCurve.cpp
     Project              : LabPlot
     Description          : A xy-curve
     --------------------------------------------------------------------
     Copyright            : (C) 2010-2015 Alexander Semke (alexander.semke@web.de)
     Copyright            : (C) 2013 Stefan Gerlach (stefan.gerlach@uni.kn)
 
  ***************************************************************************/
 
 /***************************************************************************
  *                                                                         *
  *  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.                                    *
  *                                                                         *
  *  This program is distributed in the hope that it will be useful,        *
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of         *
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
  *  GNU General Public License for more details.                           *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program; if not, write to the Free Software           *
  *   Foundation, Inc., 51 Franklin Street, Fifth Floor,                    *
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
 
 /*!
   \class XYCurve
   \brief A 2D-curve, provides an interface for editing many properties of the curve.
 
   \ingroup worksheet
 */
 
 #include "XYCurve.h"
 #include "XYCurvePrivate.h"
 #include "backend/core/column/Column.h"
 #include "backend/worksheet/plots/cartesian/CartesianCoordinateSystem.h"
 #include "backend/worksheet/plots/cartesian/CartesianPlot.h"
 #include "backend/lib/commandtemplates.h"
 #include "backend/core/Project.h"
 #include "backend/spreadsheet/Spreadsheet.h"
 #include "backend/worksheet/Worksheet.h"
 #include "backend/lib/XmlStreamReader.h"
 #include "backend/lib/macros.h"
 #include "backend/lib/trace.h"
 #include "backend/gsl/errors.h"
 #include "tools/ImageTools.h"
 
 #include <QPainter>
 #include <QGraphicsSceneContextMenuEvent>
 #include <QMenu>
 
 #include <KConfigGroup>
 #include <KLocale>
 
 extern "C" {
 #include <gsl/gsl_spline.h>
 #include <gsl/gsl_errno.h>
 }
 
 XYCurve::XYCurve(const QString &name) : WorksheetElement(name), d_ptr(new XYCurvePrivate(this)), m_menusInitialized(false) {
 	init();
 }
 
 XYCurve::XYCurve(const QString& name, XYCurvePrivate* dd) : WorksheetElement(name), d_ptr(dd), m_menusInitialized(false) {
 	init();
 }
 
 XYCurve::~XYCurve() {
 	//no need to delete the d-pointer here - it inherits from QGraphicsItem
 	//and is deleted during the cleanup in QGraphicsScene
 }
 
 void XYCurve::finalizeAdd() {
 	Q_D(XYCurve);
 	d->plot = dynamic_cast<const CartesianPlot*>(parentAspect());
 	Q_ASSERT(d->plot);
 	d->cSystem = dynamic_cast<const CartesianCoordinateSystem*>(d->plot->coordinateSystem());
 }
 
 void XYCurve::init() {
 	Q_D(XYCurve);
 
 	KConfig config;
 	KConfigGroup group = config.group("XYCurve");
 
 	d->xColumn = nullptr;
 	d->yColumn = nullptr;
 
 	d->lineType = (XYCurve::LineType) group.readEntry("LineType", (int)XYCurve::Line);
 	d->lineSkipGaps = group.readEntry("SkipLineGaps", false);
 	d->lineInterpolationPointsCount = group.readEntry("LineInterpolationPointsCount", 1);
 	d->linePen.setStyle( (Qt::PenStyle) group.readEntry("LineStyle", (int)Qt::SolidLine) );
 	d->linePen.setColor( group.readEntry("LineColor", QColor(Qt::black)) );
 	d->linePen.setWidthF( group.readEntry("LineWidth", Worksheet::convertToSceneUnits(1.0, Worksheet::Point)) );
 	d->lineOpacity = group.readEntry("LineOpacity", 1.0);
 
 	d->dropLineType = (XYCurve::DropLineType) group.readEntry("DropLineType", (int)XYCurve::NoLine);
 	d->dropLinePen.setStyle( (Qt::PenStyle) group.readEntry("DropLineStyle", (int)Qt::SolidLine) );
 	d->dropLinePen.setColor( group.readEntry("DropLineColor", QColor(Qt::black)));
 	d->dropLinePen.setWidthF( group.readEntry("DropLineWidth", Worksheet::convertToSceneUnits(1.0, Worksheet::Point)) );
 	d->dropLineOpacity = group.readEntry("DropLineOpacity", 1.0);
 
 	d->symbolsStyle = (Symbol::Style)group.readEntry("SymbolStyle", (int)Symbol::NoSymbols);
 	d->symbolsSize = group.readEntry("SymbolSize", Worksheet::convertToSceneUnits(5, Worksheet::Point));
 	d->symbolsRotationAngle = group.readEntry("SymbolRotation", 0.0);
 	d->symbolsOpacity = group.readEntry("SymbolOpacity", 1.0);
 	d->symbolsBrush.setStyle( (Qt::BrushStyle)group.readEntry("SymbolFillingStyle", (int)Qt::SolidPattern) );
 	d->symbolsBrush.setColor( group.readEntry("SymbolFillingColor", QColor(Qt::black)) );
 	d->symbolsPen.setStyle( (Qt::PenStyle)group.readEntry("SymbolBorderStyle", (int)Qt::SolidLine) );
 	d->symbolsPen.setColor( group.readEntry("SymbolBorderColor", QColor(Qt::black)) );
 	d->symbolsPen.setWidthF( group.readEntry("SymbolBorderWidth", Worksheet::convertToSceneUnits(0.0, Worksheet::Point)) );
 
 	d->valuesType = (XYCurve::ValuesType) group.readEntry("ValuesType", (int)XYCurve::NoValues);
 	d->valuesColumn = nullptr;
 	d->valuesPosition = (XYCurve::ValuesPosition) group.readEntry("ValuesPosition", (int)XYCurve::ValuesAbove);
 	d->valuesDistance = group.readEntry("ValuesDistance", Worksheet::convertToSceneUnits(5, Worksheet::Point));
 	d->valuesRotationAngle = group.readEntry("ValuesRotation", 0.0);
 	d->valuesOpacity = group.readEntry("ValuesOpacity", 1.0);
 	d->valuesPrefix = group.readEntry("ValuesPrefix", "");
 	d->valuesSuffix = group.readEntry("ValuesSuffix", "");
 	d->valuesFont = group.readEntry("ValuesFont", QFont());
 	d->valuesFont.setPixelSize( Worksheet::convertToSceneUnits( 8, Worksheet::Point ) );
 	d->valuesColor = group.readEntry("ValuesColor", QColor(Qt::black));
 
 	d->fillingPosition = (XYCurve::FillingPosition) group.readEntry("FillingPosition", (int)XYCurve::NoFilling);
 	d->fillingType = (PlotArea::BackgroundType) group.readEntry("FillingType", (int)PlotArea::Color);
 	d->fillingColorStyle = (PlotArea::BackgroundColorStyle) group.readEntry("FillingColorStyle", (int) PlotArea::SingleColor);
 	d->fillingImageStyle = (PlotArea::BackgroundImageStyle) group.readEntry("FillingImageStyle", (int) PlotArea::Scaled);
 	d->fillingBrushStyle = (Qt::BrushStyle) group.readEntry("FillingBrushStyle", (int) Qt::SolidPattern);
 	d->fillingFileName = group.readEntry("FillingFileName", QString());
 	d->fillingFirstColor = group.readEntry("FillingFirstColor", QColor(Qt::white));
 	d->fillingSecondColor = group.readEntry("FillingSecondColor", QColor(Qt::black));
 	d->fillingOpacity = group.readEntry("FillingOpacity", 1.0);
 
 	d->xErrorType = (XYCurve::ErrorType) group.readEntry("XErrorType", (int)XYCurve::NoError);
 	d->xErrorPlusColumn = nullptr;
 	d->xErrorMinusColumn = nullptr;
 	d->yErrorType = (XYCurve::ErrorType) group.readEntry("YErrorType", (int)XYCurve::NoError);
 	d->yErrorPlusColumn = nullptr;
 	d->yErrorMinusColumn = nullptr;
 	d->errorBarsType = (XYCurve::ErrorBarsType) group.readEntry("ErrorBarsType", (int)XYCurve::ErrorBarsSimple);
 	d->errorBarsCapSize = group.readEntry( "ErrorBarsCapSize", Worksheet::convertToSceneUnits(10, Worksheet::Point) );
 	d->errorBarsPen.setStyle( (Qt::PenStyle)group.readEntry("ErrorBarsStyle", (int)Qt::SolidLine) );
 	d->errorBarsPen.setColor( group.readEntry("ErrorBarsColor", QColor(Qt::black)) );
 	d->errorBarsPen.setWidthF( group.readEntry("ErrorBarsWidth", Worksheet::convertToSceneUnits(1.0, Worksheet::Point)) );
 	d->errorBarsOpacity = group.readEntry("ErrorBarsOpacity", 1.0);
 }
 
 void XYCurve::initActions() {
 	visibilityAction = new QAction(i18n("visible"), this);
 	visibilityAction->setCheckable(true);
 	connect(visibilityAction, SIGNAL(triggered()), this, SLOT(visibilityChanged()));
 
 	navigateToAction = new QAction(QIcon::fromTheme("go-next-view"), "", this);
 	connect(navigateToAction, SIGNAL(triggered()), this, SLOT(navigateTo()));
 
 	m_menusInitialized = true;
 }
 
 QMenu* XYCurve::createContextMenu() {
 	if (!m_menusInitialized)
 		initActions();
 
 
 	QMenu *menu = WorksheetElement::createContextMenu();
 	QAction* firstAction = menu->actions().at(1); //skip the first action because of the "title-action"
 	visibilityAction->setChecked(isVisible());
 	menu->insertAction(firstAction, visibilityAction);
 
 	//"data analysis" menu
 	CartesianPlot* plot = dynamic_cast<CartesianPlot*>(parentAspect());
 	menu->insertMenu(visibilityAction, plot->analysisMenu());
 	menu->insertSeparator(visibilityAction);
 
 	//"Navigate to spreadsheet"-action, show only if x- or y-columns have data from a spreadsheet
 	AbstractAspect* parentSpreadsheet = 0;
 	if (xColumn() && dynamic_cast<Spreadsheet*>(xColumn()->parentAspect()) )
 		parentSpreadsheet = xColumn()->parentAspect();
 	else if (yColumn() && dynamic_cast<Spreadsheet*>(yColumn()->parentAspect()) )
 		parentSpreadsheet = yColumn()->parentAspect();
 
 	if (parentSpreadsheet) {
 		navigateToAction->setText(i18n("Navigate to \"%1\"", parentSpreadsheet->name()));
 		navigateToAction->setData(parentSpreadsheet->path());
 		menu->insertAction(visibilityAction, navigateToAction);
 		menu->insertSeparator(visibilityAction);
 	}
 
 	//if the context menu is called on an item that is not selected yet, select it
 	if (!graphicsItem()->isSelected())
 		graphicsItem()->setSelected(true);
 
 	return menu;
 }
 
 /*!
 	Returns an icon to be used in the project explorer.
 */
 QIcon XYCurve::icon() const {
 	return QIcon::fromTheme("labplot-xy-curve");
 }
 
 QGraphicsItem* XYCurve::graphicsItem() const {
 	return d_ptr;
 }
 
 STD_SWAP_METHOD_SETTER_CMD_IMPL(XYCurve, SetVisible, bool, swapVisible)
 void XYCurve::setVisible(bool on) {
 	Q_D(XYCurve);
 	exec(new XYCurveSetVisibleCmd(d, on, on ? i18n("%1: set visible") : i18n("%1: set invisible")));
 }
 
 bool XYCurve::isVisible() const {
 	Q_D(const XYCurve);
 	return d->isVisible();
 }
 
 void XYCurve::setPrinting(bool on) {
 	Q_D(XYCurve);
 	d->setPrinting(on);
 }
 
 //##############################################################################
 //##########################  getter methods  ##################################
 //##############################################################################
 
 //data source
 BASIC_SHARED_D_READER_IMPL(XYCurve, const AbstractColumn*, xColumn, xColumn)
 BASIC_SHARED_D_READER_IMPL(XYCurve, const AbstractColumn*, yColumn, yColumn)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QString, xColumnPath, xColumnPath)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QString, yColumnPath, yColumnPath)
 
 //line
 BASIC_SHARED_D_READER_IMPL(XYCurve, XYCurve::LineType, lineType, lineType)
 BASIC_SHARED_D_READER_IMPL(XYCurve, bool, lineSkipGaps, lineSkipGaps)
 BASIC_SHARED_D_READER_IMPL(XYCurve, int, lineInterpolationPointsCount, lineInterpolationPointsCount)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QPen, linePen, linePen)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, lineOpacity, lineOpacity)
 
 //droplines
 BASIC_SHARED_D_READER_IMPL(XYCurve, XYCurve::DropLineType, dropLineType, dropLineType)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QPen, dropLinePen, dropLinePen)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, dropLineOpacity, dropLineOpacity)
 
 //symbols
 BASIC_SHARED_D_READER_IMPL(XYCurve, Symbol::Style, symbolsStyle, symbolsStyle)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, symbolsOpacity, symbolsOpacity)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, symbolsRotationAngle, symbolsRotationAngle)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, symbolsSize, symbolsSize)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QBrush, symbolsBrush, symbolsBrush)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QPen, symbolsPen, symbolsPen)
 
 //values
 BASIC_SHARED_D_READER_IMPL(XYCurve, XYCurve::ValuesType, valuesType, valuesType)
 BASIC_SHARED_D_READER_IMPL(XYCurve, const AbstractColumn *, valuesColumn, valuesColumn)
 const QString& XYCurve::valuesColumnPath() const {
 	return d_ptr->valuesColumnPath;
 }
 BASIC_SHARED_D_READER_IMPL(XYCurve, XYCurve::ValuesPosition, valuesPosition, valuesPosition)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, valuesDistance, valuesDistance)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, valuesRotationAngle, valuesRotationAngle)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, valuesOpacity, valuesOpacity)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QString, valuesPrefix, valuesPrefix)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QString, valuesSuffix, valuesSuffix)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QColor, valuesColor, valuesColor)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QFont, valuesFont, valuesFont)
 
 //filling
 BASIC_SHARED_D_READER_IMPL(XYCurve, XYCurve::FillingPosition, fillingPosition, fillingPosition)
 BASIC_SHARED_D_READER_IMPL(XYCurve, PlotArea::BackgroundType, fillingType, fillingType)
 BASIC_SHARED_D_READER_IMPL(XYCurve, PlotArea::BackgroundColorStyle, fillingColorStyle, fillingColorStyle)
 BASIC_SHARED_D_READER_IMPL(XYCurve, PlotArea::BackgroundImageStyle, fillingImageStyle, fillingImageStyle)
 CLASS_SHARED_D_READER_IMPL(XYCurve, Qt::BrushStyle, fillingBrushStyle, fillingBrushStyle)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QColor, fillingFirstColor, fillingFirstColor)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QColor, fillingSecondColor, fillingSecondColor)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QString, fillingFileName, fillingFileName)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, fillingOpacity, fillingOpacity)
 
 //error bars
 BASIC_SHARED_D_READER_IMPL(XYCurve, XYCurve::ErrorType, xErrorType, xErrorType)
 BASIC_SHARED_D_READER_IMPL(XYCurve, const AbstractColumn*, xErrorPlusColumn, xErrorPlusColumn)
 const QString& XYCurve::xErrorPlusColumnPath() const {
 	return d_ptr->xErrorPlusColumnPath;
 }
 BASIC_SHARED_D_READER_IMPL(XYCurve, const AbstractColumn*, xErrorMinusColumn, xErrorMinusColumn)
 const QString& XYCurve::xErrorMinusColumnPath() const {
 	return d_ptr->xErrorMinusColumnPath;
 }
 
 BASIC_SHARED_D_READER_IMPL(XYCurve, XYCurve::ErrorType, yErrorType, yErrorType)
 BASIC_SHARED_D_READER_IMPL(XYCurve, const AbstractColumn*, yErrorPlusColumn, yErrorPlusColumn)
 const QString& XYCurve::yErrorPlusColumnPath() const {
 	return d_ptr->yErrorPlusColumnPath;
 }
 BASIC_SHARED_D_READER_IMPL(XYCurve, const AbstractColumn*, yErrorMinusColumn, yErrorMinusColumn)
 const QString& XYCurve::yErrorMinusColumnPath() const {
 	return d_ptr->yErrorMinusColumnPath;
 }
 
 BASIC_SHARED_D_READER_IMPL(XYCurve, XYCurve::ErrorBarsType, errorBarsType, errorBarsType)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, errorBarsCapSize, errorBarsCapSize)
 CLASS_SHARED_D_READER_IMPL(XYCurve, QPen, errorBarsPen, errorBarsPen)
 BASIC_SHARED_D_READER_IMPL(XYCurve, qreal, errorBarsOpacity, errorBarsOpacity)
 
 
 /*!
  * return \c true if the data in the source columns (x, y) used in the analysis curves, \c false otherwise
  */
 bool XYCurve::isSourceDataChangedSinceLastRecalc() const {
 	Q_D(const XYCurve);
 	return d->sourceDataChangedSinceLastRecalc;
 }
 
 //##############################################################################
 //#################  setter methods and undo commands ##########################
 //##############################################################################
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetXColumn, const AbstractColumn*, xColumn, retransform)
 void XYCurve::setXColumn(const AbstractColumn* column) {
 	Q_D(XYCurve);
 	if (column != d->xColumn) {
 		exec(new XYCurveSetXColumnCmd(d, column, i18n("%1: x-data source changed")));
 
 		//emit xDataChanged() in order to notify the plot about the changes
 		emit xDataChanged();
 		if (column) {
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SIGNAL(xDataChanged()));
 
 			//update the curve itself on changes
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SLOT(retransform()));
 			connect(column->parentAspect(), SIGNAL(aspectAboutToBeRemoved(const AbstractAspect*)),
 			        this, SLOT(xColumnAboutToBeRemoved(const AbstractAspect*)));
 			//TODO: add disconnect in the undo-function
 		}
 	}
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetYColumn, const AbstractColumn*, yColumn, retransform)
 void XYCurve::setYColumn(const AbstractColumn* column) {
 	Q_D(XYCurve);
 	if (column != d->yColumn) {
 		exec(new XYCurveSetYColumnCmd(d, column, i18n("%1: y-data source changed")));
 
 		//emit yDataChanged() in order to notify the plot about the changes
 		emit yDataChanged();
 		if (column) {
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SIGNAL(yDataChanged()));
 
 			//update the curve itself on changes
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SLOT(retransform()));
 			connect(column->parentAspect(), SIGNAL(aspectAboutToBeRemoved(const AbstractAspect*)),
 			        this, SLOT(yColumnAboutToBeRemoved(const AbstractAspect*)));
 			//TODO: add disconnect in the undo-function
 		}
 	}
 }
 
 void XYCurve::setXColumnPath(const QString& path) {
 	Q_D(XYCurve);
 	d->xColumnPath = path;
 }
 
 void XYCurve::setYColumnPath(const QString& path) {
 	Q_D(XYCurve);
 	d->yColumnPath = path;
 }
 
 //Line
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetLineType, XYCurve::LineType, lineType, updateLines)
 void XYCurve::setLineType(LineType type) {
 	Q_D(XYCurve);
 	if (type != d->lineType)
 		exec(new XYCurveSetLineTypeCmd(d, type, i18n("%1: line type changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetLineSkipGaps, bool, lineSkipGaps, updateLines)
 void XYCurve::setLineSkipGaps(bool skip) {
 	Q_D(XYCurve);
 	if (skip != d->lineSkipGaps)
 		exec(new XYCurveSetLineSkipGapsCmd(d, skip, i18n("%1: set skip line gaps")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetLineInterpolationPointsCount, int, lineInterpolationPointsCount, updateLines)
 void XYCurve::setLineInterpolationPointsCount(int count) {
 	Q_D(XYCurve);
 	if (count != d->lineInterpolationPointsCount)
 		exec(new XYCurveSetLineInterpolationPointsCountCmd(d, count, i18n("%1: set the number of interpolation points")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetLinePen, QPen, linePen, recalcShapeAndBoundingRect)
 void XYCurve::setLinePen(const QPen &pen) {
 	Q_D(XYCurve);
 	if (pen != d->linePen)
 		exec(new XYCurveSetLinePenCmd(d, pen, i18n("%1: set line style")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetLineOpacity, qreal, lineOpacity, updatePixmap);
 void XYCurve::setLineOpacity(qreal opacity) {
 	Q_D(XYCurve);
 	if (opacity != d->lineOpacity)
 		exec(new XYCurveSetLineOpacityCmd(d, opacity, i18n("%1: set line opacity")));
 }
 
 //Drop lines
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetDropLineType, XYCurve::DropLineType, dropLineType, updateDropLines)
 void XYCurve::setDropLineType(DropLineType type) {
 	Q_D(XYCurve);
 	if (type != d->dropLineType)
 		exec(new XYCurveSetDropLineTypeCmd(d, type, i18n("%1: drop line type changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetDropLinePen, QPen, dropLinePen, recalcShapeAndBoundingRect)
 void XYCurve::setDropLinePen(const QPen &pen) {
 	Q_D(XYCurve);
 	if (pen != d->dropLinePen)
 		exec(new XYCurveSetDropLinePenCmd(d, pen, i18n("%1: set drop line style")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetDropLineOpacity, qreal, dropLineOpacity, updatePixmap)
 void XYCurve::setDropLineOpacity(qreal opacity) {
 	Q_D(XYCurve);
 	if (opacity != d->dropLineOpacity)
 		exec(new XYCurveSetDropLineOpacityCmd(d, opacity, i18n("%1: set drop line opacity")));
 }
 
 // Symbols-Tab
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetSymbolsStyle, Symbol::Style, symbolsStyle, updateSymbols)
 void XYCurve::setSymbolsStyle(Symbol::Style style) {
 	Q_D(XYCurve);
 	if (style != d->symbolsStyle)
 		exec(new XYCurveSetSymbolsStyleCmd(d, style, i18n("%1: set symbol style")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetSymbolsSize, qreal, symbolsSize, updateSymbols)
 void XYCurve::setSymbolsSize(qreal size) {
 	Q_D(XYCurve);
 	if (!qFuzzyCompare(1 + size, 1 + d->symbolsSize))
 		exec(new XYCurveSetSymbolsSizeCmd(d, size, i18n("%1: set symbol size")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetSymbolsRotationAngle, qreal, symbolsRotationAngle, updateSymbols)
 void XYCurve::setSymbolsRotationAngle(qreal angle) {
 	Q_D(XYCurve);
 	if (!qFuzzyCompare(1 + angle, 1 + d->symbolsRotationAngle))
 		exec(new XYCurveSetSymbolsRotationAngleCmd(d, angle, i18n("%1: rotate symbols")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetSymbolsBrush, QBrush, symbolsBrush, updatePixmap)
 void XYCurve::setSymbolsBrush(const QBrush &brush) {
 	Q_D(XYCurve);
 	if (brush != d->symbolsBrush)
 		exec(new XYCurveSetSymbolsBrushCmd(d, brush, i18n("%1: set symbol filling")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetSymbolsPen, QPen, symbolsPen, updateSymbols)
 void XYCurve::setSymbolsPen(const QPen &pen) {
 	Q_D(XYCurve);
 	if (pen != d->symbolsPen)
 		exec(new XYCurveSetSymbolsPenCmd(d, pen, i18n("%1: set symbol outline style")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetSymbolsOpacity, qreal, symbolsOpacity, updatePixmap)
 void XYCurve::setSymbolsOpacity(qreal opacity) {
 	Q_D(XYCurve);
 	if (opacity != d->symbolsOpacity)
 		exec(new XYCurveSetSymbolsOpacityCmd(d, opacity, i18n("%1: set symbols opacity")));
 }
 
 //Values-Tab
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesType, XYCurve::ValuesType, valuesType, updateValues)
 void XYCurve::setValuesType(XYCurve::ValuesType type) {
 	Q_D(XYCurve);
 	if (type != d->valuesType)
 		exec(new XYCurveSetValuesTypeCmd(d, type, i18n("%1: set values type")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesColumn, const AbstractColumn*, valuesColumn, updateValues)
 void XYCurve::setValuesColumn(const AbstractColumn* column) {
 	Q_D(XYCurve);
 	if (column != d->valuesColumn) {
 		exec(new XYCurveSetValuesColumnCmd(d, column, i18n("%1: set values column")));
 		if (column) {
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SLOT(updateValues()));
 			connect(column->parentAspect(), SIGNAL(aspectAboutToBeRemoved(const AbstractAspect*)),
 			        this, SLOT(valuesColumnAboutToBeRemoved(const AbstractAspect*)));
 		}
 	}
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesPosition, XYCurve::ValuesPosition, valuesPosition, updateValues)
 void XYCurve::setValuesPosition(ValuesPosition position) {
 	Q_D(XYCurve);
 	if (position != d->valuesPosition)
 		exec(new XYCurveSetValuesPositionCmd(d, position, i18n("%1: set values position")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesDistance, qreal, valuesDistance, updateValues)
 void XYCurve::setValuesDistance(qreal distance) {
 	Q_D(XYCurve);
 	if (distance != d->valuesDistance)
 		exec(new XYCurveSetValuesDistanceCmd(d, distance, i18n("%1: set values distance")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesRotationAngle, qreal, valuesRotationAngle, updateValues)
 void XYCurve::setValuesRotationAngle(qreal angle) {
 	Q_D(XYCurve);
 	if (!qFuzzyCompare(1 + angle, 1 + d->valuesRotationAngle))
 		exec(new XYCurveSetValuesRotationAngleCmd(d, angle, i18n("%1: rotate values")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesOpacity, qreal, valuesOpacity, updatePixmap)
 void XYCurve::setValuesOpacity(qreal opacity) {
 	Q_D(XYCurve);
 	if (opacity != d->valuesOpacity)
 		exec(new XYCurveSetValuesOpacityCmd(d, opacity, i18n("%1: set values opacity")));
 }
 
 //TODO: Format, Precision
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesPrefix, QString, valuesPrefix, updateValues)
 void XYCurve::setValuesPrefix(const QString& prefix) {
 	Q_D(XYCurve);
 	if (prefix != d->valuesPrefix)
 		exec(new XYCurveSetValuesPrefixCmd(d, prefix, i18n("%1: set values prefix")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesSuffix, QString, valuesSuffix, updateValues)
 void XYCurve::setValuesSuffix(const QString& suffix) {
 	Q_D(XYCurve);
 	if (suffix != d->valuesSuffix)
 		exec(new XYCurveSetValuesSuffixCmd(d, suffix, i18n("%1: set values suffix")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesFont, QFont, valuesFont, updateValues)
 void XYCurve::setValuesFont(const QFont& font) {
 	Q_D(XYCurve);
 	if (font != d->valuesFont)
 		exec(new XYCurveSetValuesFontCmd(d, font, i18n("%1: set values font")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetValuesColor, QColor, valuesColor, updatePixmap)
 void XYCurve::setValuesColor(const QColor& color) {
 	Q_D(XYCurve);
 	if (color != d->valuesColor)
 		exec(new XYCurveSetValuesColorCmd(d, color, i18n("%1: set values color")));
 }
 
 //Filling
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingPosition, XYCurve::FillingPosition, fillingPosition, updateFilling)
 void XYCurve::setFillingPosition(FillingPosition position) {
 	Q_D(XYCurve);
 	if (position != d->fillingPosition)
 		exec(new XYCurveSetFillingPositionCmd(d, position, i18n("%1: filling position changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingType, PlotArea::BackgroundType, fillingType, updatePixmap)
 void XYCurve::setFillingType(PlotArea::BackgroundType type) {
 	Q_D(XYCurve);
 	if (type != d->fillingType)
 		exec(new XYCurveSetFillingTypeCmd(d, type, i18n("%1: filling type changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingColorStyle, PlotArea::BackgroundColorStyle, fillingColorStyle, updatePixmap)
 void XYCurve::setFillingColorStyle(PlotArea::BackgroundColorStyle style) {
 	Q_D(XYCurve);
 	if (style != d->fillingColorStyle)
 		exec(new XYCurveSetFillingColorStyleCmd(d, style, i18n("%1: filling color style changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingImageStyle, PlotArea::BackgroundImageStyle, fillingImageStyle, updatePixmap)
 void XYCurve::setFillingImageStyle(PlotArea::BackgroundImageStyle style) {
 	Q_D(XYCurve);
 	if (style != d->fillingImageStyle)
 		exec(new XYCurveSetFillingImageStyleCmd(d, style, i18n("%1: filling image style changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingBrushStyle, Qt::BrushStyle, fillingBrushStyle, updatePixmap)
 void XYCurve::setFillingBrushStyle(Qt::BrushStyle style) {
 	Q_D(XYCurve);
 	if (style != d->fillingBrushStyle)
 		exec(new XYCurveSetFillingBrushStyleCmd(d, style, i18n("%1: filling brush style changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingFirstColor, QColor, fillingFirstColor, updatePixmap)
 void XYCurve::setFillingFirstColor(const QColor& color) {
 	Q_D(XYCurve);
 	if (color != d->fillingFirstColor)
 		exec(new XYCurveSetFillingFirstColorCmd(d, color, i18n("%1: set filling first color")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingSecondColor, QColor, fillingSecondColor, updatePixmap)
 void XYCurve::setFillingSecondColor(const QColor& color) {
 	Q_D(XYCurve);
 	if (color != d->fillingSecondColor)
 		exec(new XYCurveSetFillingSecondColorCmd(d, color, i18n("%1: set filling second color")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingFileName, QString, fillingFileName, updatePixmap)
 void XYCurve::setFillingFileName(const QString& fileName) {
 	Q_D(XYCurve);
 	if (fileName != d->fillingFileName)
 		exec(new XYCurveSetFillingFileNameCmd(d, fileName, i18n("%1: set filling image")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetFillingOpacity, qreal, fillingOpacity, updatePixmap)
 void XYCurve::setFillingOpacity(qreal opacity) {
 	Q_D(XYCurve);
 	if (opacity != d->fillingOpacity)
 		exec(new XYCurveSetFillingOpacityCmd(d, opacity, i18n("%1: set filling opacity")));
 }
 
 //Error bars
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetXErrorType, XYCurve::ErrorType, xErrorType, updateErrorBars)
 void XYCurve::setXErrorType(ErrorType type) {
 	Q_D(XYCurve);
 	if (type != d->xErrorType)
 		exec(new XYCurveSetXErrorTypeCmd(d, type, i18n("%1: x-error type changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetXErrorPlusColumn, const AbstractColumn*, xErrorPlusColumn, updateErrorBars)
 void XYCurve::setXErrorPlusColumn(const AbstractColumn* column) {
 	Q_D(XYCurve);
 	if (column != d->xErrorPlusColumn) {
 		exec(new XYCurveSetXErrorPlusColumnCmd(d, column, i18n("%1: set x-error column")));
 		if (column) {
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SLOT(updateErrorBars()));
 			connect(column->parentAspect(), SIGNAL(aspectAboutToBeRemoved(const AbstractAspect*)),
 			        this, SLOT(xErrorPlusColumnAboutToBeRemoved(const AbstractAspect*)));
 		}
 	}
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetXErrorMinusColumn, const AbstractColumn*, xErrorMinusColumn, updateErrorBars)
 void XYCurve::setXErrorMinusColumn(const AbstractColumn* column) {
 	Q_D(XYCurve);
 	if (column != d->xErrorMinusColumn) {
 		exec(new XYCurveSetXErrorMinusColumnCmd(d, column, i18n("%1: set x-error column")));
 		if (column) {
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SLOT(updateErrorBars()));
 			connect(column->parentAspect(), SIGNAL(aspectAboutToBeRemoved(const AbstractAspect*)),
 			        this, SLOT(xErrorMinusColumnAboutToBeRemoved(const AbstractAspect*)));
 		}
 	}
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetYErrorType, XYCurve::ErrorType, yErrorType, updateErrorBars)
 void XYCurve::setYErrorType(ErrorType type) {
 	Q_D(XYCurve);
 	if (type != d->yErrorType)
 		exec(new XYCurveSetYErrorTypeCmd(d, type, i18n("%1: y-error type changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetYErrorPlusColumn, const AbstractColumn*, yErrorPlusColumn, updateErrorBars)
 void XYCurve::setYErrorPlusColumn(const AbstractColumn* column) {
 	Q_D(XYCurve);
 	if (column != d->yErrorPlusColumn) {
 		exec(new XYCurveSetYErrorPlusColumnCmd(d, column, i18n("%1: set y-error column")));
 		if (column) {
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SLOT(updateErrorBars()));
 			connect(column->parentAspect(), SIGNAL(aspectAboutToBeRemoved(const AbstractAspect*)),
 			        this, SLOT(yErrorPlusColumnAboutToBeRemoved(const AbstractAspect*)));
 		}
 	}
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetYErrorMinusColumn, const AbstractColumn*, yErrorMinusColumn, updateErrorBars)
 void XYCurve::setYErrorMinusColumn(const AbstractColumn* column) {
 	Q_D(XYCurve);
 	if (column != d->yErrorMinusColumn) {
 		exec(new XYCurveSetYErrorMinusColumnCmd(d, column, i18n("%1: set y-error column")));
 		if (column) {
 			connect(column, SIGNAL(dataChanged(const AbstractColumn*)), this, SLOT(updateErrorBars()));
 			connect(column->parentAspect(), SIGNAL(aspectAboutToBeRemoved(const AbstractAspect*)),
 			        this, SLOT(yErrorMinusColumnAboutToBeRemoved(const AbstractAspect*)));
 		}
 	}
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetErrorBarsCapSize, qreal, errorBarsCapSize, updateErrorBars)
 void XYCurve::setErrorBarsCapSize(qreal size) {
 	Q_D(XYCurve);
 	if (size != d->errorBarsCapSize)
 		exec(new XYCurveSetErrorBarsCapSizeCmd(d, size, i18n("%1: set error bar cap size")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetErrorBarsType, XYCurve::ErrorBarsType, errorBarsType, updateErrorBars)
 void XYCurve::setErrorBarsType(ErrorBarsType type) {
 	Q_D(XYCurve);
 	if (type != d->errorBarsType)
 		exec(new XYCurveSetErrorBarsTypeCmd(d, type, i18n("%1: error bar type changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetErrorBarsPen, QPen, errorBarsPen, recalcShapeAndBoundingRect)
 void XYCurve::setErrorBarsPen(const QPen& pen) {
 	Q_D(XYCurve);
 	if (pen != d->errorBarsPen)
 		exec(new XYCurveSetErrorBarsPenCmd(d, pen, i18n("%1: set error bar style")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(XYCurve, SetErrorBarsOpacity, qreal, errorBarsOpacity, updatePixmap)
 void XYCurve::setErrorBarsOpacity(qreal opacity) {
 	Q_D(XYCurve);
 	if (opacity != d->errorBarsOpacity)
 		exec(new XYCurveSetErrorBarsOpacityCmd(d, opacity, i18n("%1: set error bar opacity")));
 }
 
 void XYCurve::suppressRetransform(bool b) {
 	Q_D(XYCurve);
 	d->suppressRetransform(b);
 }
 
 //##############################################################################
 //#################################  SLOTS  ####################################
 //##############################################################################
 void XYCurve::retransform() {
 	Q_D(XYCurve);
 	d->retransform();
 }
 
 void XYCurve::updateValues() {
 	Q_D(XYCurve);
 	d->updateValues();
 }
 
 void XYCurve::updateErrorBars() {
 	Q_D(XYCurve);
 	d->updateErrorBars();
 }
 
 //TODO
 void XYCurve::handleResize(double horizontalRatio, double verticalRatio, bool pageResize) {
 	Q_UNUSED(pageResize);
 	Q_D(const XYCurve);
 
 	setSymbolsSize(d->symbolsSize * horizontalRatio);
 
 	QPen pen = d->symbolsPen;
 	pen.setWidthF(pen.widthF() * (horizontalRatio + verticalRatio) / 2.0);
 	setSymbolsPen(pen);
 
 	pen = d->linePen;
 	pen.setWidthF(pen.widthF() * (horizontalRatio + verticalRatio) / 2.0);
 	setLinePen(pen);
 
 	//setValuesDistance(d->distance*);
 	QFont font=d->valuesFont;
 	font.setPointSizeF(font.pointSizeF()*horizontalRatio);
 	setValuesFont(font);
 }
 
 void XYCurve::xColumnAboutToBeRemoved(const AbstractAspect* aspect) {
 	Q_D(XYCurve);
 	if (aspect == d->xColumn) {
 		d->xColumn = 0;
 		d->retransform();
 	}
 }
 
 void XYCurve::yColumnAboutToBeRemoved(const AbstractAspect* aspect) {
 	Q_D(XYCurve);
 	if (aspect == d->yColumn) {
 		d->yColumn = 0;
 		d->retransform();
 	}
 }
 
 void XYCurve::valuesColumnAboutToBeRemoved(const AbstractAspect* aspect) {
 	Q_D(XYCurve);
 	if (aspect == d->valuesColumn) {
 		d->valuesColumn = 0;
 		d->updateValues();
 	}
 }
 
 void XYCurve::xErrorPlusColumnAboutToBeRemoved(const AbstractAspect* aspect) {
 	Q_D(XYCurve);
 	if (aspect == d->xErrorPlusColumn) {
 		d->xErrorPlusColumn = 0;
 		d->updateErrorBars();
 	}
 }
 
 void XYCurve::xErrorMinusColumnAboutToBeRemoved(const AbstractAspect* aspect) {
 	Q_D(XYCurve);
 	if (aspect == d->xErrorMinusColumn) {
 		d->xErrorMinusColumn = 0;
 		d->updateErrorBars();
 	}
 }
 
 void XYCurve::yErrorPlusColumnAboutToBeRemoved(const AbstractAspect* aspect) {
 	Q_D(XYCurve);
 	if (aspect == d->yErrorPlusColumn) {
 		d->yErrorPlusColumn = 0;
 		d->updateErrorBars();
 	}
 }
 
 void XYCurve::yErrorMinusColumnAboutToBeRemoved(const AbstractAspect* aspect) {
 	Q_D(XYCurve);
 	if (aspect == d->yErrorMinusColumn) {
 		d->yErrorMinusColumn = 0;
 		d->updateErrorBars();
 	}
 }
 
 //##############################################################################
 //######  SLOTs for changes triggered via QActions in the context menu  ########
 //##############################################################################
 void XYCurve::visibilityChanged() {
 	Q_D(const XYCurve);
 	this->setVisible(!d->isVisible());
 }
 
 void XYCurve::navigateTo() {
 	project()->navigateTo(navigateToAction->data().toString());
 }
 
 //##############################################################################
 //######################### Private implementation #############################
 //##############################################################################
 XYCurvePrivate::XYCurvePrivate(XYCurve *owner) :
 	sourceDataChangedSinceLastRecalc(false),
 	q(owner),
 	plot(nullptr),
 	cSystem(nullptr),
 	m_hoverEffectImageIsDirty(false),
 	m_selectionEffectImageIsDirty(false),
 	m_hovered(false),
 	m_suppressRecalc(false),
 	m_suppressRetransform(false),
 	m_printing(false) {
 
 	setFlag(QGraphicsItem::ItemIsSelectable, true);
 	setAcceptHoverEvents(true);
 }
 
 QString XYCurvePrivate::name() const {
 	return q->name();
 }
 
 QRectF XYCurvePrivate::boundingRect() const {
 	return boundingRectangle;
 }
 
 /*!
   Returns the shape of the XYCurve as a QPainterPath in local coordinates
 */
 QPainterPath XYCurvePrivate::shape() const {
 	return curveShape;
 }
 
 void XYCurvePrivate::contextMenuEvent(QGraphicsSceneContextMenuEvent* event) {
 	q->createContextMenu()->exec(event->screenPos());
 }
 
 bool XYCurvePrivate::swapVisible(bool on) {
 	bool oldValue = isVisible();
 	setVisible(on);
 	emit q->visibilityChanged(on);
 	return oldValue;
 }
 
 /*!
   recalculates the position of the points to be drawn. Called when the data was changed.
   Triggers the update of lines, drop lines, symbols etc.
 */
 void XYCurvePrivate::retransform() {
 	if (m_suppressRetransform || !plot)
 		return;
 
 #ifdef PERFTRACE_CURVES
 	PERFTRACE(name().toLatin1() + ", XYCurvePrivate::retransform()");
 #endif
 	symbolPointsLogical.clear();
 	symbolPointsScene.clear();
 	connectedPointsLogical.clear();
 
 	if ( (NULL == xColumn) || (NULL == yColumn) ) {
 		linePath = QPainterPath();
 		dropLinePath = QPainterPath();
 		symbolsPath = QPainterPath();
 		valuesPath = QPainterPath();
 		errorBarsPath = QPainterPath();
 		recalcShapeAndBoundingRect();
 		return;
 	}
 
-	WAIT_CURSOR;
-	QApplication::processEvents(QEventLoop::AllEvents, 0);
+	if (!plot->isPanningActive()) {
+		WAIT_CURSOR;
+		QApplication::processEvents(QEventLoop::AllEvents, 0);
+	}
 
 	QPointF tempPoint;
 
 	AbstractColumn::ColumnMode xColMode = xColumn->columnMode();
 	AbstractColumn::ColumnMode yColMode = yColumn->columnMode();
 
 	//take over only valid and non masked points.
 	for (int row = 0; row < xColumn->rowCount(); row++) {
 		if ( xColumn->isValid(row) && yColumn->isValid(row)
 		        && (!xColumn->isMasked(row)) && (!yColumn->isMasked(row)) ) {
 			switch (xColMode) {
 			case AbstractColumn::Numeric:
 			case AbstractColumn::Integer:
 				tempPoint.setX(xColumn->valueAt(row));
 				break;
 			case AbstractColumn::Text:	//TODO
 			case AbstractColumn::DateTime:
 			case AbstractColumn::Month:
 			case AbstractColumn::Day:
 				break;
 			}
 
 			switch (yColMode) {
 			case AbstractColumn::Numeric:
 			case AbstractColumn::Integer:
 				tempPoint.setY(yColumn->valueAt(row));
 				break;
 			case AbstractColumn::Text:	//TODO
 			case AbstractColumn::DateTime:
 			case AbstractColumn::Month:
 			case AbstractColumn::Day:
 				break;
 			}
 			symbolPointsLogical.append(tempPoint);
 			connectedPointsLogical.push_back(true);
 		} else {
 			if (!connectedPointsLogical.empty())
 				connectedPointsLogical[connectedPointsLogical.size()-1] = false;
 		}
 	}
 
 	//calculate the scene coordinates
 	visiblePoints = std::vector<bool>(symbolPointsLogical.count(), false);
 	{
 #ifdef PERFTRACE_CURVES
 		PERFTRACE(name().toLatin1() + ", XYCurvePrivate::retransform(), map logical points to scene coordinates");
 #endif
 		cSystem->mapLogicalToScene(symbolPointsLogical, symbolPointsScene, visiblePoints);
 	}
 
 	m_suppressRecalc = true;
 	updateLines();
 	updateDropLines();
 	updateSymbols();
 	updateValues();
 	m_suppressRecalc = false;
 	updateErrorBars();
 
 	RESET_CURSOR;
 }
 
 /*!
   recalculates the painter path for the lines connecting the data points.
   Called each time when the type of this connection is changed.
 */
 void XYCurvePrivate::updateLines() {
 #ifdef PERFTRACE_CURVES
 	PERFTRACE(name().toLatin1() + ", XYCurvePrivate::updateLines()");
 #endif
 	linePath = QPainterPath();
 	lines.clear();
 	if (lineType == XYCurve::NoLine) {
 		updateFilling();
 		recalcShapeAndBoundingRect();
 		return;
 	}
 
 	unsigned int count = (unsigned int)symbolPointsLogical.count();
 	if (count <= 1) {
 		//nothing to do, if no data points available
 		recalcShapeAndBoundingRect();
 		return;
 	}
 
 	//calculate the lines connecting the data points
 	{
 #ifdef PERFTRACE_CURVES
 	PERFTRACE(name().toLatin1() + ", XYCurvePrivate::updateLines(), calculate the lines connecting the data points");
 #endif
 	QPointF tempPoint1, tempPoint2;
 	QPointF curPoint, nextPoint;
 	switch (lineType) {
 	case XYCurve::NoLine:
 		break;
 	case XYCurve::Line:
 		for (unsigned int i = 0; i < count - 1; i++) {
 			if (!lineSkipGaps && !connectedPointsLogical[i]) continue;
 			lines.append(QLineF(symbolPointsLogical.at(i), symbolPointsLogical.at(i+1)));
 		}
 		break;
 	case XYCurve::StartHorizontal:
 		for (unsigned int i = 0; i < count - 1; i++) {
 			if (!lineSkipGaps && !connectedPointsLogical[i]) continue;
 			curPoint = symbolPointsLogical.at(i);
 			nextPoint = symbolPointsLogical.at(i+1);
 			tempPoint1 = QPointF(nextPoint.x(), curPoint.y());
 			lines.append(QLineF(curPoint, tempPoint1));
 			lines.append(QLineF(tempPoint1, nextPoint));
 		}
 		break;
 	case XYCurve::StartVertical:
 		for (unsigned int i = 0; i < count - 1; i++) {
 			if (!lineSkipGaps && !connectedPointsLogical[i]) continue;
 			curPoint = symbolPointsLogical.at(i);
 			nextPoint = symbolPointsLogical.at(i+1);
 			tempPoint1 = QPointF(curPoint.x(), nextPoint.y());
 			lines.append(QLineF(curPoint, tempPoint1));
 			lines.append(QLineF(tempPoint1,nextPoint));
 		}
 		break;
 	case XYCurve::MidpointHorizontal:
 		for (unsigned int i = 0; i < count - 1; i++) {
 			if (!lineSkipGaps && !connectedPointsLogical[i]) continue;
 			curPoint = symbolPointsLogical.at(i);
 			nextPoint = symbolPointsLogical.at(i+1);
 			tempPoint1 = QPointF(curPoint.x() + (nextPoint.x()-curPoint.x())/2, curPoint.y());
 			tempPoint2 = QPointF(curPoint.x() + (nextPoint.x()-curPoint.x())/2, nextPoint.y());
 			lines.append(QLineF(curPoint, tempPoint1));
 			lines.append(QLineF(tempPoint1, tempPoint2));
 			lines.append(QLineF(tempPoint2, nextPoint));
 		}
 		break;
 	case XYCurve::MidpointVertical:
 		for (unsigned int i = 0; i < count - 1; i++) {
 			if (!lineSkipGaps && !connectedPointsLogical[i]) continue;
 			curPoint = symbolPointsLogical.at(i);
 			nextPoint = symbolPointsLogical.at(i+1);
 			tempPoint1 = QPointF(curPoint.x(), curPoint.y() + (nextPoint.y()-curPoint.y())/2);
 			tempPoint2 = QPointF(nextPoint.x(), curPoint.y() + (nextPoint.y()-curPoint.y())/2);
 			lines.append(QLineF(curPoint, tempPoint1));
 			lines.append(QLineF(tempPoint1, tempPoint2));
 			lines.append(QLineF(tempPoint2, nextPoint));
 		}
 		break;
 	case XYCurve::Segments2: {
 			int skip=0;
 			for (unsigned int i = 0; i < count - 1; i++) {
 				if (skip != 1) {
 					if (!lineSkipGaps && !connectedPointsLogical[i]) {
 						skip = 0;
 						continue;
 					}
 					lines.append(QLineF(symbolPointsLogical.at(i), symbolPointsLogical.at(i+1)));
 					skip++;
 				} else
 					skip = 0;
 			}
 			break;
 		}
 	case XYCurve::Segments3: {
 			int skip = 0;
 			for (unsigned int i = 0; i < count - 1; i++) {
 				if (skip != 2) {
 					if (!lineSkipGaps && !connectedPointsLogical[i]) {
 						skip = 0;
 						continue;
 					}
 					lines.append(QLineF(symbolPointsLogical.at(i), symbolPointsLogical.at(i+1)));
 					skip++;
 				} else
 					skip = 0;
 			}
 			break;
 		}
 	case XYCurve::SplineCubicNatural:
 	case XYCurve::SplineCubicPeriodic:
 	case XYCurve::SplineAkimaNatural:
 	case XYCurve::SplineAkimaPeriodic: {
 			gsl_interp_accel *acc = gsl_interp_accel_alloc();
 			gsl_spline *spline = 0;
 
 			double* x = new double[count];
 			double* y = new double[count];
 			for (unsigned int i = 0; i < count; i++) {
 				x[i] = symbolPointsLogical.at(i).x();
 				y[i] = symbolPointsLogical.at(i).y();
 			}
 
 			gsl_set_error_handler_off();
 			if (lineType == XYCurve::SplineCubicNatural)
 				spline = gsl_spline_alloc(gsl_interp_cspline, count);
 			else if (lineType == XYCurve::SplineCubicPeriodic)
 				spline = gsl_spline_alloc(gsl_interp_cspline_periodic, count);
 			else if (lineType == XYCurve::SplineAkimaNatural)
 				spline = gsl_spline_alloc(gsl_interp_akima, count);
 			else if (lineType == XYCurve::SplineAkimaPeriodic)
 				spline = gsl_spline_alloc(gsl_interp_akima_periodic, count);
 
 			if (!spline) {
 				QString msg;
 				if ( (lineType == XYCurve::SplineAkimaNatural || lineType == XYCurve::SplineAkimaPeriodic) && count < 5)
 					msg = i18n("Error: Akima spline interpolation requires a minimum of 5 points.");
 				else
 					msg = i18n("Error: Couldn't initialize the spline function.");
 				emit q->info(msg);
 
 				recalcShapeAndBoundingRect();
 				delete[] x;
 				delete[] y;
 				gsl_interp_accel_free (acc);
 				return;
 			}
 
 			int status = gsl_spline_init (spline, x, y, count);
 			if (status) {
 				//TODO: check in gsl/interp.c when GSL_EINVAL is thrown
 				QString gslError;
 				if (status == GSL_EINVAL)
 					gslError = i18n("x values must be monotonically increasing.");
 				else
 					gslError = gslErrorToString(status);
 				emit q->info( i18n("Error: %1").arg(gslError) );
 
 				recalcShapeAndBoundingRect();
 				delete[] x;
 				delete[] y;
 				gsl_spline_free (spline);
 				gsl_interp_accel_free (acc);
 				return;
 			}
 
 			//create interpolating points
 			std::vector<double> xinterp, yinterp;
 			double step;
 			double xi, yi, x1, x2;
 			for (unsigned int i = 0; i < count - 1; i++) {
 				x1 = x[i];
 				x2 = x[i+1];
 				step=fabs(x2 - x1)/(lineInterpolationPointsCount + 1);
 
 				for (xi = x1; xi < x2; xi += step) {
 					yi = gsl_spline_eval(spline, xi, acc);
 					xinterp.push_back(xi);
 					yinterp.push_back(yi);
 				}
 			}
 
 			for (unsigned int i = 0; i < xinterp.size() - 1; i++)
 				lines.append(QLineF(xinterp[i], yinterp[i], xinterp[i+1], yinterp[i+1]));
 			lines.append(QLineF(xinterp[xinterp.size()-1], yinterp[yinterp.size()-1], x[count-1], y[count-1]));
 
 			delete[] x;
 			delete[] y;
 			gsl_spline_free (spline);
 			gsl_interp_accel_free (acc);
 			break;
 		}
 	}
 	}
 
 	//map the lines to scene coordinates
 	{
 #ifdef PERFTRACE_CURVES
 		PERFTRACE(name().toLatin1() + ", XYCurvePrivate::updateLines(), map lines to scene coordinates");
 #endif
 		lines = cSystem->mapLogicalToScene(lines);
 	}
 
 	{
 #ifdef PERFTRACE_CURVES
 	PERFTRACE(name().toLatin1() + ", XYCurvePrivate::updateLines(), calculate new line path");
 #endif
 	//new line path
 	for (const auto& line : lines) {
 		linePath.moveTo(line.p1());
 		linePath.lineTo(line.p2());
 	}
 	}
 
 	updateFilling();
 	recalcShapeAndBoundingRect();
 }
 
 /*!
   recalculates the painter path for the drop lines.
   Called each time when the type of the drop lines is changed.
 */
 void XYCurvePrivate::updateDropLines() {
 	dropLinePath = QPainterPath();
 	if (dropLineType == XYCurve::NoDropLine) {
 		recalcShapeAndBoundingRect();
 		return;
 	}
 
 	//calculate drop lines
 	QVector<QLineF> lines;
 	float xMin = 0;
 	float yMin = 0;
 
 	xMin = plot->xMin();
 	yMin = plot->yMin();
 	switch (dropLineType) {
 	case XYCurve::NoDropLine:
 		break;
 	case XYCurve::DropLineX:
 		for(int i=0; i<symbolPointsLogical.size(); ++i) {
 			if (!visiblePoints[i]) continue;
 			const QPointF& point = symbolPointsLogical.at(i);
 			lines.append(QLineF(point, QPointF(point.x(), yMin)));
 		}
 		break;
 	case XYCurve::DropLineY:
 		for(int i=0; i<symbolPointsLogical.size(); ++i) {
 			if (!visiblePoints[i]) continue;
 			const QPointF& point = symbolPointsLogical.at(i);
 			lines.append(QLineF(point, QPointF(xMin, point.y())));
 		}
 		break;
 	case XYCurve::DropLineXY:
 		for(int i=0; i<symbolPointsLogical.size(); ++i) {
 			if (!visiblePoints[i]) continue;
 			const QPointF& point = symbolPointsLogical.at(i);
 			lines.append(QLineF(point, QPointF(point.x(), yMin)));
 			lines.append(QLineF(point, QPointF(xMin, point.y())));
 		}
 		break;
 	case XYCurve::DropLineXZeroBaseline:
 		for(int i=0; i<symbolPointsLogical.size(); ++i) {
 			if (!visiblePoints[i]) continue;
 			const QPointF& point = symbolPointsLogical.at(i);
 			lines.append(QLineF(point, QPointF(point.x(), 0)));
 		}
 		break;
 	case XYCurve::DropLineXMinBaseline:
 		for(int i=0; i<symbolPointsLogical.size(); ++i) {
 			if (!visiblePoints[i]) continue;
 			const QPointF& point = symbolPointsLogical.at(i);
 			lines.append( QLineF(point, QPointF(point.x(), dynamic_cast<const Column*>(yColumn)->minimum())) );
 		}
 		break;
 	case XYCurve::DropLineXMaxBaseline:
 		for(int i=0; i<symbolPointsLogical.size(); ++i) {
 			if (!visiblePoints[i]) continue;
 			const QPointF& point = symbolPointsLogical.at(i);
 			lines.append( QLineF(point, QPointF(point.x(), dynamic_cast<const Column*>(yColumn)->maximum())) );
 		}
 		break;
 	}
 
 	//map the drop lines to scene coordinates
 	lines = cSystem->mapLogicalToScene(lines);
 
 	//new painter path for the drop lines
 	for (const auto& line : lines) {
 		dropLinePath.moveTo(line.p1());
 		dropLinePath.lineTo(line.p2());
 	}
 
 	recalcShapeAndBoundingRect();
 }
 
 void XYCurvePrivate::updateSymbols() {
 	symbolsPath = QPainterPath();
 	if (symbolsStyle != Symbol::NoSymbols) {
 		QPainterPath path = Symbol::pathFromStyle(symbolsStyle);
 
 		QTransform trafo;
 		trafo.scale(symbolsSize, symbolsSize);
 		path = trafo.map(path);
 		trafo.reset();
 
 		if (symbolsRotationAngle != 0) {
 			trafo.rotate(symbolsRotationAngle);
 			path = trafo.map(path);
 		}
 
 		for (const auto& point : symbolPointsScene) {
 			trafo.reset();
 			trafo.translate(point.x(), point.y());
 			symbolsPath.addPath(trafo.map(path));
 		}
 	}
 
 	recalcShapeAndBoundingRect();
 }
 
 /*!
   recreates the value strings to be shown and recalculates their draw position.
 */
 void XYCurvePrivate::updateValues() {
 	valuesPath = QPainterPath();
 	valuesPoints.clear();
 	valuesStrings.clear();
 
 	if (valuesType == XYCurve::NoValues) {
 		recalcShapeAndBoundingRect();
 		return;
 	}
 
 	//determine the value string for all points that are currently visible in the plot
 	switch (valuesType) {
 	case XYCurve::NoValues:
 	case XYCurve::ValuesX: {
 			for(int i=0; i<symbolPointsLogical.size(); ++i) {
 				if (!visiblePoints[i]) continue;
 				valuesStrings << valuesPrefix + QString::number(symbolPointsLogical.at(i).x()) + valuesSuffix;
 			}
 			break;
 		}
 	case XYCurve::ValuesY: {
 			for(int i=0; i<symbolPointsLogical.size(); ++i) {
 				if (!visiblePoints[i]) continue;
 				valuesStrings << valuesPrefix + QString::number(symbolPointsLogical.at(i).y()) + valuesSuffix;
 			}
 			break;
 		}
 	case XYCurve::ValuesXY: {
 			for(int i=0; i<symbolPointsLogical.size(); ++i) {
 				if (!visiblePoints[i]) continue;
 				valuesStrings << valuesPrefix + QString::number(symbolPointsLogical.at(i).x()) + ','
 				              + QString::number(symbolPointsLogical.at(i).y()) + valuesSuffix;
 			}
 			break;
 		}
 	case XYCurve::ValuesXYBracketed: {
 			for(int i=0; i<symbolPointsLogical.size(); ++i) {
 				if (!visiblePoints[i]) continue;
 				valuesStrings <<  valuesPrefix + '(' + QString::number(symbolPointsLogical.at(i).x()) + ','
 				              + QString::number(symbolPointsLogical.at(i).y()) +')' + valuesSuffix;
 			}
 			break;
 		}
 	case XYCurve::ValuesCustomColumn: {
 			if (!valuesColumn) {
 				recalcShapeAndBoundingRect();
 				return;
 			}
 
 			int endRow;
 			if (symbolPointsLogical.size()>valuesColumn->rowCount())
 				endRow =  valuesColumn->rowCount();
 			else
 				endRow = symbolPointsLogical.size();
 
 			AbstractColumn::ColumnMode xColMode = valuesColumn->columnMode();
 			for (int i = 0; i < endRow; ++i) {
 				if (!visiblePoints[i]) continue;
 
 				if ( !valuesColumn->isValid(i) || valuesColumn->isMasked(i) )
 					continue;
 
 				switch (xColMode) {
 				case AbstractColumn::Numeric:
 				case AbstractColumn::Integer:
 					valuesStrings << valuesPrefix + QString::number(valuesColumn->valueAt(i)) + valuesSuffix;
 					break;
 				case AbstractColumn::Text:
 					valuesStrings << valuesPrefix + valuesColumn->textAt(i) + valuesSuffix;
 				case AbstractColumn::DateTime:
 				case AbstractColumn::Month:
 				case AbstractColumn::Day:
 					//TODO
 					break;
 				}
 			}
 		}
 	}
 
 	//Calculate the coordinates where to paint the value strings.
 	//The coordinates depend on the actual size of the string.
 	QPointF tempPoint;
 	QFontMetrics fm(valuesFont);
 	qreal w;
 	qreal h=fm.ascent();
 
 	for (int i=0; i<valuesStrings.size(); i++) {
 		w=fm.width(valuesStrings.at(i));
 		switch (valuesPosition) {
 		case XYCurve::ValuesAbove:
 			tempPoint.setX( symbolPointsScene.at(i).x() - w/2);
 			tempPoint.setY( symbolPointsScene.at(i).y() - valuesDistance );
 			break;
 		case XYCurve::ValuesUnder:
 			tempPoint.setX( symbolPointsScene.at(i).x() -w/2 );
 			tempPoint.setY( symbolPointsScene.at(i).y() + valuesDistance + h/2);
 			break;
 		case XYCurve::ValuesLeft:
 			tempPoint.setX( symbolPointsScene.at(i).x() - valuesDistance - w - 1 );
 			tempPoint.setY( symbolPointsScene.at(i).y());
 			break;
 		case XYCurve::ValuesRight:
 			tempPoint.setX( symbolPointsScene.at(i).x() + valuesDistance - 1 );
 			tempPoint.setY( symbolPointsScene.at(i).y() );
 			break;
 		}
 		valuesPoints.append(tempPoint);
 	}
 
 	QTransform trafo;
 	QPainterPath path;
 	for (int i=0; i<valuesPoints.size(); i++) {
 		path = QPainterPath();
 		path.addText( QPoint(0,0), valuesFont, valuesStrings.at(i) );
 
 		trafo.reset();
 		trafo.translate( valuesPoints.at(i).x(), valuesPoints.at(i).y() );
 		if (valuesRotationAngle!=0)
 			trafo.rotate( -valuesRotationAngle );
 
 		valuesPath.addPath(trafo.map(path));
 	}
 
 	recalcShapeAndBoundingRect();
 }
 
 void XYCurvePrivate::updateFilling() {
 	if (m_suppressRetransform)
 		return;
 
 	fillPolygons.clear();
 
 	//don't try to calculate the filling polygons if no filling was enabled or the nubmer of visible points on the scene is too high
 	if (fillingPosition==XYCurve::NoFilling || symbolPointsScene.size()>1000) {
 		recalcShapeAndBoundingRect();
 		return;
 	}
 
 	QVector<QLineF> fillLines;
 
 	//if there're no interpolation lines available (XYCurve::NoLine selected), create line-interpolation,
 	//use already available lines otherwise.
 	if (!lines.isEmpty())
 		fillLines = lines;
 	else {
 		for (int i=0; i<symbolPointsLogical.count()-1; i++) {
 			if (!lineSkipGaps && !connectedPointsLogical[i]) continue;
 			fillLines.append(QLineF(symbolPointsLogical.at(i), symbolPointsLogical.at(i+1)));
 		}
 		fillLines = cSystem->mapLogicalToScene(fillLines);
 
 		//no lines available (no points), nothing to do
 		if (fillLines.isEmpty())
 			return;
 	}
 
 	//create polygon(s):
 	//1. Depending on the current zoom-level, only a subset of the curve may be visible in the plot
 	//and more of the filling area should be shown than the area defined by the start and end points of the currently visible points.
 	//We check first whether the curve crosses the boundaries of the plot and determine new start and end points and put them to the boundaries.
 	//2. Furthermore, depending on the current filling type we determine the end point (x- or y-coordinate) where all polygons are closed at the end.
 	QPolygonF pol;
 	QPointF start = fillLines.at(0).p1(); //starting point of the current polygon, initialize with the first visible point
 	QPointF end = fillLines.at(fillLines.size()-1).p2(); //starting point of the current polygon, initialize with the last visible point
 	const QPointF& first = symbolPointsLogical.at(0); //first point of the curve, may not be visible currently
 	const QPointF& last = symbolPointsLogical.at(symbolPointsLogical.size()-1);//first point of the curve, may not be visible currently
 	QPointF edge;
 	float xEnd=0, yEnd=0;
 	if (fillingPosition == XYCurve::FillingAbove) {
 		edge = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMin()));
 
 		//start point
 		if (AbstractCoordinateSystem::essentiallyEqual(start.y(), edge.y())) {
 			if (first.x() < plot->xMin())
 				start = edge;
 			else if (first.x() > plot->xMax())
 				start = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMin()));
 			else
 				start = cSystem->mapLogicalToScene(QPointF(first.x(), plot->yMin()));
 		}
 
 		//end point
 		if (AbstractCoordinateSystem::essentiallyEqual(end.y(), edge.y())) {
 			if (last.x() < plot->xMin())
 				end = edge;
 			else if (last.x() > plot->xMax())
 				end = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMin()));
 			else
 				end = cSystem->mapLogicalToScene(QPointF(last.x(), plot->yMin()));
 		}
 
 		//coordinate at which to close all polygons
 		yEnd = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMax())).y();
 	} else if (fillingPosition == XYCurve::FillingBelow) {
 		edge = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMax()));
 
 		//start point
 		if (AbstractCoordinateSystem::essentiallyEqual(start.y(), edge.y())) {
 			if (first.x() < plot->xMin())
 				start = edge;
 			else if (first.x() > plot->xMax())
 				start = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMax()));
 			else
 				start = cSystem->mapLogicalToScene(QPointF(first.x(), plot->yMax()));
 		}
 
 		//end point
 		if (AbstractCoordinateSystem::essentiallyEqual(end.y(), edge.y())) {
 			if (last.x() < plot->xMin())
 				end = edge;
 			else if (last.x() > plot->xMax())
 				end = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMax()));
 			else
 				end = cSystem->mapLogicalToScene(QPointF(last.x(), plot->yMax()));
 		}
 
 		//coordinate at which to close all polygons
 		yEnd = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMin())).y();
 	} else if (fillingPosition == XYCurve::FillingZeroBaseline) {
 		edge = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMax()));
 
 		//start point
 		if (AbstractCoordinateSystem::essentiallyEqual(start.y(), edge.y())) {
 			if (plot->yMax()>0) {
 				if (first.x() < plot->xMin())
 					start = edge;
 				else if (first.x() > plot->xMax())
 					start = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMax()));
 				else
 					start = cSystem->mapLogicalToScene(QPointF(first.x(), plot->yMax()));
 			} else {
 				if (first.x() < plot->xMin())
 					start = edge;
 				else if (first.x() > plot->xMax())
 					start = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMin()));
 				else
 					start = cSystem->mapLogicalToScene(QPointF(first.x(), plot->yMin()));
 			}
 		}
 
 		//end point
 		if (AbstractCoordinateSystem::essentiallyEqual(end.y(), edge.y())) {
 			if (plot->yMax()>0) {
 				if (last.x() < plot->xMin())
 					end = edge;
 				else if (last.x() > plot->xMax())
 					end = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMax()));
 				else
 					end = cSystem->mapLogicalToScene(QPointF(last.x(), plot->yMax()));
 			} else {
 				if (last.x() < plot->xMin())
 					end = edge;
 				else if (last.x() > plot->xMax())
 					end = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMin()));
 				else
 					end = cSystem->mapLogicalToScene(QPointF(last.x(), plot->yMin()));
 			}
 		}
 
 		yEnd = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMin()>0 ? plot->yMin() : 0)).y();
 	} else if (fillingPosition == XYCurve::FillingLeft) {
 		edge = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMin()));
 
 		//start point
 		if (AbstractCoordinateSystem::essentiallyEqual(start.x(), edge.x())) {
 			if (first.y() < plot->yMin())
 				start = edge;
 			else if (first.y() > plot->yMax())
 				start = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMax()));
 			else
 				start = cSystem->mapLogicalToScene(QPointF(plot->xMax(), first.y()));
 		}
 
 		//end point
 		if (AbstractCoordinateSystem::essentiallyEqual(end.x(), edge.x())) {
 			if (last.y() < plot->yMin())
 				end = edge;
 			else if (last.y() > plot->yMax())
 				end = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMax()));
 			else
 				end = cSystem->mapLogicalToScene(QPointF(plot->xMax(), last.y()));
 		}
 
 		//coordinate at which to close all polygons
 		xEnd = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMin())).x();
 	} else { //FillingRight
 		edge = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMin()));
 
 		//start point
 		if (AbstractCoordinateSystem::essentiallyEqual(start.x(), edge.x())) {
 			if (first.y() < plot->yMin())
 				start = edge;
 			else if (first.y() > plot->yMax())
 				start = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMax()));
 			else
 				start = cSystem->mapLogicalToScene(QPointF(plot->xMin(), first.y()));
 		}
 
 		//end point
 		if (AbstractCoordinateSystem::essentiallyEqual(end.x(), edge.x())) {
 			if (last.y() < plot->yMin())
 				end = edge;
 			else if (last.y() > plot->yMax())
 				end = cSystem->mapLogicalToScene(QPointF(plot->xMin(), plot->yMax()));
 			else
 				end = cSystem->mapLogicalToScene(QPointF(plot->xMin(), last.y()));
 		}
 
 		//coordinate at which to close all polygons
 		xEnd = cSystem->mapLogicalToScene(QPointF(plot->xMax(), plot->yMin())).x();
 	}
 
 	if (start != fillLines.at(0).p1())
 		pol << start;
 
 	QPointF p1, p2;
 	for (int i=0; i<fillLines.size(); ++i) {
 		const QLineF& line = fillLines.at(i);
 		p1 = line.p1();
 		p2 = line.p2();
 		if (i!=0 && p1!=fillLines.at(i-1).p2()) {
 			//the first point of the current line is not equal to the last point of the previous line
 			//->check whether we have a break in between.
 			bool gap = false; //TODO
 			if (!gap) {
 				//-> we have no break in the curve -> connect the points by a horizontal/vertical line
 				pol << fillLines.at(i-1).p2() << p1;
 			} else {
 				//-> we have a break in the curve -> close the polygon add it to the polygon list and start a new polygon
 				if (fillingPosition==XYCurve::FillingAbove || fillingPosition==XYCurve::FillingBelow || fillingPosition==XYCurve::FillingZeroBaseline) {
 					pol << QPointF(fillLines.at(i-1).p2().x(), yEnd);
 					pol << QPointF(start.x(), yEnd);
 				} else {
 					pol << QPointF(xEnd, fillLines.at(i-1).p2().y());
 					pol << QPointF(xEnd, start.y());
 				}
 
 				fillPolygons << pol;
 				pol.clear();
 				start = p1;
 			}
 		}
 		pol << p1 << p2;
 	}
 
 	if (p2!=end)
 		pol << end;
 
 	//close the last polygon
 	if (fillingPosition==XYCurve::FillingAbove || fillingPosition==XYCurve::FillingBelow || fillingPosition==XYCurve::FillingZeroBaseline) {
 		pol << QPointF(end.x(), yEnd);
 		pol << QPointF(start.x(), yEnd);
 	} else {
 		pol << QPointF(xEnd, end.y());
 		pol << QPointF(xEnd, start.y());
 	}
 
 	fillPolygons << pol;
 	recalcShapeAndBoundingRect();
 }
 
 void XYCurvePrivate::updateErrorBars() {
 	errorBarsPath = QPainterPath();
 	if (xErrorType==XYCurve::NoError && yErrorType==XYCurve::NoError) {
 		recalcShapeAndBoundingRect();
 		return;
 	}
 
 	QVector<QLineF> lines;
 	float errorPlus, errorMinus;
 
 	//the cap size for the errorbars is given in scene units.
 	//determine first the (half of the) cap size in logical units:
 	// * take the first visible point in logical units
 	// * convert it to scene units
 	// * add to this point an offset corresponding to the cap size in scene units
 	// * convert this point back to logical units
 	// * subtract from this point the original coordinates (without the new offset)
 	//   to determine the cap size in logical units.
 	float capSizeX = 0;
 	float capSizeY = 0;
 	if (errorBarsType != XYCurve::ErrorBarsSimple && !symbolPointsLogical.isEmpty()) {
 		//determine the index of the first visible point
 		size_t i = 0;
 		while (i<visiblePoints.size() && !visiblePoints[i])
 			i++;
 
 		if (i == visiblePoints.size())
 			return; //no visible points -> no error bars to draw
 
 		//cap size for x-error bars
 		QPointF pointScene = cSystem->mapLogicalToScene(symbolPointsLogical.at((int)i));
 		pointScene.setY(pointScene.y()-errorBarsCapSize);
 		QPointF pointLogical = cSystem->mapSceneToLogical(pointScene);
 		capSizeX = (pointLogical.y() - symbolPointsLogical.at((int)i).y())/2;
 
 		//cap size for y-error bars
 		pointScene = cSystem->mapLogicalToScene(symbolPointsLogical.at((int)i));
 		pointScene.setX(pointScene.x()+errorBarsCapSize);
 		pointLogical = cSystem->mapSceneToLogical(pointScene);
 		capSizeY = (pointLogical.x() - symbolPointsLogical.at((int)i).x())/2;
 	}
 
 	for (int i=0; i < symbolPointsLogical.size(); ++i) {
 		if (!visiblePoints[i])
 			continue;
 
 		const QPointF& point = symbolPointsLogical.at(i);
 
 		//error bars for x
 		if (xErrorType != XYCurve::NoError) {
 			//determine the values for the errors
 			if (xErrorPlusColumn && xErrorPlusColumn->isValid(i) && !xErrorPlusColumn->isMasked(i))
 				errorPlus = xErrorPlusColumn->valueAt(i);
 			else
 				errorPlus = 0;
 
 			if (xErrorType==XYCurve::SymmetricError)
 				errorMinus = errorPlus;
 			else {
 				if (xErrorMinusColumn && xErrorMinusColumn->isValid(i) && !xErrorMinusColumn->isMasked(i))
 					errorMinus = xErrorMinusColumn->valueAt(i);
 				else
 					errorMinus = 0;
 			}
 
 			//draw the error bars
 			switch (errorBarsType) {
 			case XYCurve::ErrorBarsSimple:
 				lines.append(QLineF(QPointF(point.x()-errorMinus, point.y()),
 				                    QPointF(point.x()+errorPlus, point.y())));
 				break;
 			case XYCurve::ErrorBarsWithEnds:
 				lines.append(QLineF(QPointF(point.x()-errorMinus, point.y()),
 				                    QPointF(point.x()+errorPlus, point.y())));
 				if (errorMinus!=0) {
 					lines.append(QLineF(QPointF(point.x()-errorMinus, point.y()-capSizeX),
 					                    QPointF(point.x()-errorMinus, point.y()+capSizeX)));
 				}
 				if (errorPlus!=0) {
 					lines.append(QLineF(QPointF(point.x()+errorPlus, point.y()-capSizeX),
 					                    QPointF(point.x()+errorPlus, point.y()+capSizeX)));
 				}
 				break;
 			}
 		}
 
 		//error bars for y
 		if (yErrorType != XYCurve::NoError) {
 			//determine the values for the errors
 			if (yErrorPlusColumn && yErrorPlusColumn->isValid(i) && !yErrorPlusColumn->isMasked(i))
 				errorPlus = yErrorPlusColumn->valueAt(i);
 			else
 				errorPlus = 0;
 
 			if (yErrorType == XYCurve::SymmetricError)
 				errorMinus = errorPlus;
 			else {
 				if (yErrorMinusColumn && yErrorMinusColumn->isValid(i) && !yErrorMinusColumn->isMasked(i) )
 					errorMinus = yErrorMinusColumn->valueAt(i);
 				else
 					errorMinus = 0;
 			}
 
 			//draw the error bars
 			switch (errorBarsType) {
 			case XYCurve::ErrorBarsSimple:
 				lines.append(QLineF(QPointF(point.x(), point.y()-errorMinus),
 				                    QPointF(point.x(), point.y()+errorPlus)));
 				break;
 			case XYCurve::ErrorBarsWithEnds:
 				lines.append(QLineF(QPointF(point.x(), point.y()-errorMinus),
 				                    QPointF(point.x(), point.y()+errorPlus)));
 				if (errorMinus != 0)
 					lines.append(QLineF(QPointF(point.x()-capSizeY, point.y()-errorMinus),
 					                    QPointF(point.x()+capSizeY, point.y()-errorMinus)));
 				if (errorPlus != 0)
 					lines.append(QLineF(QPointF(point.x()-capSizeY, point.y()+errorPlus),
 					                    QPointF(point.x()+capSizeY, point.y()+errorPlus)));
 				break;
 			}
 		}
 	}
 
 	//map the error bars to scene coordinates
 	lines = cSystem->mapLogicalToScene(lines);
 
 	//new painter path for the drop lines
 	for (const auto& line : lines) {
 		errorBarsPath.moveTo(line.p1());
 		errorBarsPath.lineTo(line.p2());
 	}
 
 	recalcShapeAndBoundingRect();
 }
 
 /*!
   recalculates the outer bounds and the shape of the curve.
 */
 void XYCurvePrivate::recalcShapeAndBoundingRect() {
 	if (m_suppressRecalc)
 		return;
 
 #ifdef PERFTRACE_CURVES
 	PERFTRACE(name().toLatin1() + ", XYCurvePrivate::recalcShapeAndBoundingRect()");
 #endif
 
 	prepareGeometryChange();
 	curveShape = QPainterPath();
 	if (lineType != XYCurve::NoLine)
 		curveShape.addPath(WorksheetElement::shapeFromPath(linePath, linePen));
 
 	if (dropLineType != XYCurve::NoDropLine)
 		curveShape.addPath(WorksheetElement::shapeFromPath(dropLinePath, dropLinePen));
 
 	if (symbolsStyle != Symbol::NoSymbols)
 		curveShape.addPath(symbolsPath);
 
 	if (valuesType != XYCurve::NoValues)
 		curveShape.addPath(valuesPath);
 
 	if (xErrorType != XYCurve::NoError || yErrorType != XYCurve::NoError)
 		curveShape.addPath(WorksheetElement::shapeFromPath(errorBarsPath, errorBarsPen));
 
 	boundingRectangle = curveShape.boundingRect();
 
 	for (const auto& pol : fillPolygons)
 		boundingRectangle = boundingRectangle.united(pol.boundingRect());
 
 	//TODO: when the selection is painted, line intersections are visible.
 	//simplified() removes those artifacts but is horrible slow for curves with large number of points.
 	//search for an alternative.
 	//curveShape = curveShape.simplified();
 
 	updatePixmap();
 }
 
 void XYCurvePrivate::draw(QPainter* painter) {
 #ifdef PERFTRACE_CURVES
 	PERFTRACE(name().toLatin1() + ", XYCurvePrivate::draw()");
 #endif
 
 	//draw filling
 	if (fillingPosition != XYCurve::NoFilling) {
 		painter->setOpacity(fillingOpacity);
 		painter->setPen(Qt::SolidLine);
 		drawFilling(painter);
 	}
 
 	//draw lines
 	if (lineType != XYCurve::NoLine) {
 		painter->setOpacity(lineOpacity);
 		painter->setPen(linePen);
 		painter->setBrush(Qt::NoBrush);
 		painter->drawPath(linePath);
 	}
 
 	//draw drop lines
 	if (dropLineType != XYCurve::NoDropLine) {
 		painter->setOpacity(dropLineOpacity);
 		painter->setPen(dropLinePen);
 		painter->setBrush(Qt::NoBrush);
 		painter->drawPath(dropLinePath);
 	}
 
 	//draw error bars
 	if ( (xErrorType != XYCurve::NoError) || (yErrorType != XYCurve::NoError) ) {
 		painter->setOpacity(errorBarsOpacity);
 		painter->setPen(errorBarsPen);
 		painter->setBrush(Qt::NoBrush);
 		painter->drawPath(errorBarsPath);
 	}
 
 	//draw symbols
 	if (symbolsStyle != Symbol::NoSymbols) {
 		painter->setOpacity(symbolsOpacity);
 		painter->setPen(symbolsPen);
 		painter->setBrush(symbolsBrush);
 		drawSymbols(painter);
 	}
 
 	//draw values
 	if (valuesType != XYCurve::NoValues) {
 		painter->setOpacity(valuesOpacity);
 		//don't use any painter pen, since this will force QPainter to render the text outline which is expensive
 		painter->setPen(Qt::NoPen);
 		painter->setBrush(valuesColor);
 		drawValues(painter);
 	}
 }
 
 void XYCurvePrivate::updatePixmap() {
     if (m_suppressRecalc)
         return;
 	WAIT_CURSOR;
 
 	m_hoverEffectImageIsDirty = true;
 	m_selectionEffectImageIsDirty = true;
 	if (boundingRectangle.width() == 0 || boundingRectangle.width() == 0) {
 		m_pixmap = QPixmap();
 		RESET_CURSOR;
 		return;
 	}
 	QPixmap pixmap(ceil(boundingRectangle.width()), ceil(boundingRectangle.height()));
 	pixmap.fill(Qt::transparent);
 	QPainter painter(&pixmap);
 	painter.setRenderHint(QPainter::Antialiasing, true);
 	painter.translate(-boundingRectangle.topLeft());
 
 	draw(&painter);
 	painter.end();
 	m_pixmap = pixmap;
 
 	update();
 	RESET_CURSOR;
 }
 
 /*!
   Reimplementation of QGraphicsItem::paint(). This function does the actual painting of the curve.
   \sa QGraphicsItem::paint().
 */
 void XYCurvePrivate::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget) {
 	Q_UNUSED(option);
 	Q_UNUSED(widget);
 	if (!isVisible())
 		return;
 
 	painter->setPen(Qt::NoPen);
 	painter->setBrush(Qt::NoBrush);
 	painter->setRenderHint(QPainter::SmoothPixmapTransform, true);
 
 	if ( KSharedConfig::openConfig()->group("Settings_Worksheet").readEntry<bool>("DoubleBuffering", true) )
 		painter->drawPixmap(boundingRectangle.topLeft(), m_pixmap); //draw the cached pixmap (fast)
 	else
 		draw(painter); //draw directly again (slow)
 
 
 	if (m_hovered && !isSelected() && !m_printing) {
 		if (m_hoverEffectImageIsDirty) {
 			QPixmap pix = m_pixmap;
 			pix.fill(QApplication::palette().color(QPalette::Shadow));
 			pix.setAlphaChannel(m_pixmap.alphaChannel());
 			m_hoverEffectImage = ImageTools::blurred(pix.toImage(), m_pixmap.rect(), 5);
 			m_hoverEffectImageIsDirty = false;
 		}
 
 		painter->drawImage(boundingRectangle.topLeft(), m_hoverEffectImage, m_pixmap.rect());
 		return;
 	}
 
 	if (isSelected() && !m_printing) {
 		if (m_selectionEffectImageIsDirty) {
 			QPixmap pix = m_pixmap;
 			pix.fill(QApplication::palette().color(QPalette::Highlight));
 			pix.setAlphaChannel(m_pixmap.alphaChannel());
 			m_selectionEffectImage = ImageTools::blurred(pix.toImage(), m_pixmap.rect(), 5);
 			m_selectionEffectImageIsDirty = false;
 		}
 
 		painter->drawImage(boundingRectangle.topLeft(), m_selectionEffectImage, m_pixmap.rect());
 		return;
 	}
 }
 
 /*!
 	Drawing of symbolsPath is very slow, so we draw every symbol in the loop which is much faster (factor 10)
 */
 void XYCurvePrivate::drawSymbols(QPainter* painter) {
 	QPainterPath path = Symbol::pathFromStyle(symbolsStyle);
 
 	QTransform trafo;
 	trafo.scale(symbolsSize, symbolsSize);
 	path = trafo.map(path);
 	trafo.reset();
 	if (symbolsRotationAngle != 0) {
 		trafo.rotate(symbolsRotationAngle);
 		path = trafo.map(path);
 	}
 	for (const auto& point : symbolPointsScene) {
 		trafo.reset();
 		trafo.translate(point.x(), point.y());
 		painter->drawPath(trafo.map(path));
 	}
 }
 
 void XYCurvePrivate::drawValues(QPainter* painter) {
 	QTransform trafo;
 	QPainterPath path;
 	for (int i=0; i<valuesPoints.size(); i++) {
 		path = QPainterPath();
 		path.addText( QPoint(0,0), valuesFont, valuesStrings.at(i) );
 
 		trafo.reset();
 		trafo.translate( valuesPoints.at(i).x(), valuesPoints.at(i).y() );
 		if (valuesRotationAngle!=0)
 			trafo.rotate( -valuesRotationAngle );
 
 		painter->drawPath(trafo.map(path));
 	}
 }
 
 void XYCurvePrivate::drawFilling(QPainter* painter) {
 	for (const auto& pol : fillPolygons) {
 		QRectF rect = pol.boundingRect();
 		if (fillingType == PlotArea::Color) {
 			switch (fillingColorStyle) {
 			case PlotArea::SingleColor: {
 					painter->setBrush(QBrush(fillingFirstColor));
 					break;
 				}
 			case PlotArea::HorizontalLinearGradient: {
 					QLinearGradient linearGrad(rect.topLeft(), rect.topRight());
 					linearGrad.setColorAt(0, fillingFirstColor);
 					linearGrad.setColorAt(1, fillingSecondColor);
 					painter->setBrush(QBrush(linearGrad));
 					break;
 				}
 			case PlotArea::VerticalLinearGradient: {
 					QLinearGradient linearGrad(rect.topLeft(), rect.bottomLeft());
 					linearGrad.setColorAt(0, fillingFirstColor);
 					linearGrad.setColorAt(1, fillingSecondColor);
 					painter->setBrush(QBrush(linearGrad));
 					break;
 				}
 			case PlotArea::TopLeftDiagonalLinearGradient: {
 					QLinearGradient linearGrad(rect.topLeft(), rect.bottomRight());
 					linearGrad.setColorAt(0, fillingFirstColor);
 					linearGrad.setColorAt(1, fillingSecondColor);
 					painter->setBrush(QBrush(linearGrad));
 					break;
 				}
 			case PlotArea::BottomLeftDiagonalLinearGradient: {
 					QLinearGradient linearGrad(rect.bottomLeft(), rect.topRight());
 					linearGrad.setColorAt(0, fillingFirstColor);
 					linearGrad.setColorAt(1, fillingSecondColor);
 					painter->setBrush(QBrush(linearGrad));
 					break;
 				}
 			case PlotArea::RadialGradient: {
 					QRadialGradient radialGrad(rect.center(), rect.width()/2);
 					radialGrad.setColorAt(0, fillingFirstColor);
 					radialGrad.setColorAt(1, fillingSecondColor);
 					painter->setBrush(QBrush(radialGrad));
 					break;
 				}
 			}
 		} else if (fillingType == PlotArea::Image) {
 			if ( !fillingFileName.trimmed().isEmpty() ) {
 				QPixmap pix(fillingFileName);
 				switch (fillingImageStyle) {
 				case PlotArea::ScaledCropped:
 					pix = pix.scaled(rect.size().toSize(), Qt::KeepAspectRatioByExpanding, Qt::SmoothTransformation);
 					painter->setBrush(QBrush(pix));
 					painter->setBrushOrigin(pix.size().width()/2, pix.size().height()/2);
 					break;
 				case PlotArea::Scaled:
 					pix = pix.scaled(rect.size().toSize(), Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
 					painter->setBrush(QBrush(pix));
 					painter->setBrushOrigin(pix.size().width()/2, pix.size().height()/2);
 					break;
 				case PlotArea::ScaledAspectRatio:
 					pix = pix.scaled(rect.size().toSize(), Qt::KeepAspectRatio, Qt::SmoothTransformation);
 					painter->setBrush(QBrush(pix));
 					painter->setBrushOrigin(pix.size().width()/2, pix.size().height()/2);
 					break;
 				case PlotArea::Centered: {
 						QPixmap backpix(rect.size().toSize());
 						backpix.fill();
 						QPainter p(&backpix);
 						p.drawPixmap(QPointF(0, 0), pix);
 						p.end();
 						painter->setBrush(QBrush(backpix));
 						painter->setBrushOrigin(-pix.size().width()/2, -pix.size().height()/2);
 						break;
 					}
 				case PlotArea::Tiled:
 					painter->setBrush(QBrush(pix));
 					break;
 				case PlotArea::CenterTiled:
 					painter->setBrush(QBrush(pix));
 					painter->setBrushOrigin(pix.size().width()/2, pix.size().height()/2);
 				}
 			}
 		} else if (fillingType == PlotArea::Pattern)
 			painter->setBrush(QBrush(fillingFirstColor, fillingBrushStyle));
 
 		painter->drawPolygon(pol);
 	}
 }
 
 void XYCurvePrivate::hoverEnterEvent(QGraphicsSceneHoverEvent*) {
 	const CartesianPlot* plot = dynamic_cast<const CartesianPlot*>(q->parentAspect());
 	if (plot->mouseMode() == CartesianPlot::SelectionMode && !isSelected()) {
 		m_hovered = true;
 		q->hovered();
 		update();
 	}
 }
 
 void XYCurvePrivate::hoverLeaveEvent(QGraphicsSceneHoverEvent*) {
 	const CartesianPlot* plot = dynamic_cast<const CartesianPlot*>(q->parentAspect());
 	if (plot->mouseMode() == CartesianPlot::SelectionMode && m_hovered) {
 		m_hovered = false;
 		q->unhovered();
 		update();
 	}
 }
 
 void XYCurvePrivate::setPrinting(bool on) {
 	m_printing = on;
 }
 void XYCurvePrivate::suppressRetransform(bool on) {
 	m_suppressRetransform = on;
 }
 
 //##############################################################################
 //##################  Serialization/Deserialization  ###########################
 //##############################################################################
 //! Save as XML
 void XYCurve::save(QXmlStreamWriter* writer) const {
 	Q_D(const XYCurve);
 
 	writer->writeStartElement( "xyCurve" );
 	writeBasicAttributes( writer );
 	writeCommentElement( writer );
 
 	//general
 	writer->writeStartElement( "general" );
 	WRITE_COLUMN(d->xColumn, xColumn);
 	WRITE_COLUMN(d->yColumn, yColumn);
 	writer->writeAttribute( "visible", QString::number(d->isVisible()) );
 	writer->writeEndElement();
 
 	//Line
 	writer->writeStartElement( "lines" );
 	writer->writeAttribute( "type", QString::number(d->lineType) );
 	writer->writeAttribute( "skipGaps", QString::number(d->lineSkipGaps) );
 	writer->writeAttribute( "interpolationPointsCount", QString::number(d->lineInterpolationPointsCount) );
 	WRITE_QPEN(d->linePen);
 	writer->writeAttribute( "opacity", QString::number(d->lineOpacity) );
 	writer->writeEndElement();
 
 	//Drop lines
 	writer->writeStartElement( "dropLines" );
 	writer->writeAttribute( "type", QString::number(d->dropLineType) );
 	WRITE_QPEN(d->dropLinePen);
 	writer->writeAttribute( "opacity", QString::number(d->dropLineOpacity) );
 	writer->writeEndElement();
 
 	//Symbols
 	writer->writeStartElement( "symbols" );
 	writer->writeAttribute( "symbolsStyle", QString::number(d->symbolsStyle) );
 	writer->writeAttribute( "opacity", QString::number(d->symbolsOpacity) );
 	writer->writeAttribute( "rotation", QString::number(d->symbolsRotationAngle) );
 	writer->writeAttribute( "size", QString::number(d->symbolsSize) );
 	WRITE_QBRUSH(d->symbolsBrush);
 	WRITE_QPEN(d->symbolsPen);
 	writer->writeEndElement();
 
 	//Values
 	writer->writeStartElement( "values" );
 	writer->writeAttribute( "type", QString::number(d->valuesType) );
 	WRITE_COLUMN(d->valuesColumn, valuesColumn);
 	writer->writeAttribute( "position", QString::number(d->valuesPosition) );
 	writer->writeAttribute( "distance", QString::number(d->valuesDistance) );
 	writer->writeAttribute( "rotation", QString::number(d->valuesRotationAngle) );
 	writer->writeAttribute( "opacity", QString::number(d->valuesOpacity) );
 	//TODO values format and precision
 	writer->writeAttribute( "prefix", d->valuesPrefix );
 	writer->writeAttribute( "suffix", d->valuesSuffix );
 	WRITE_QCOLOR(d->valuesColor);
 	WRITE_QFONT(d->valuesFont);
 	writer->writeEndElement();
 
 	//Filling
 	writer->writeStartElement( "filling" );
 	writer->writeAttribute( "position", QString::number(d->fillingPosition) );
 	writer->writeAttribute( "type", QString::number(d->fillingType) );
 	writer->writeAttribute( "colorStyle", QString::number(d->fillingColorStyle) );
 	writer->writeAttribute( "imageStyle", QString::number(d->fillingImageStyle) );
 	writer->writeAttribute( "brushStyle", QString::number(d->fillingBrushStyle) );
 	writer->writeAttribute( "firstColor_r", QString::number(d->fillingFirstColor.red()) );
 	writer->writeAttribute( "firstColor_g", QString::number(d->fillingFirstColor.green()) );
 	writer->writeAttribute( "firstColor_b", QString::number(d->fillingFirstColor.blue()) );
 	writer->writeAttribute( "secondColor_r", QString::number(d->fillingSecondColor.red()) );
 	writer->writeAttribute( "secondColor_g", QString::number(d->fillingSecondColor.green()) );
 	writer->writeAttribute( "secondColor_b", QString::number(d->fillingSecondColor.blue()) );
 	writer->writeAttribute( "fileName", d->fillingFileName );
 	writer->writeAttribute( "opacity", QString::number(d->fillingOpacity) );
 	writer->writeEndElement();
 
 	//Error bars
 	writer->writeStartElement( "errorBars" );
 	writer->writeAttribute( "xErrorType", QString::number(d->xErrorType) );
 	WRITE_COLUMN(d->xErrorPlusColumn, xErrorPlusColumn);
 	WRITE_COLUMN(d->xErrorMinusColumn, xErrorMinusColumn);
 	writer->writeAttribute( "yErrorType", QString::number(d->yErrorType) );
 	WRITE_COLUMN(d->yErrorPlusColumn, yErrorPlusColumn);
 	WRITE_COLUMN(d->yErrorMinusColumn, yErrorMinusColumn);
 	writer->writeAttribute( "type", QString::number(d->errorBarsType) );
 	writer->writeAttribute( "capSize", QString::number(d->errorBarsCapSize) );
 	WRITE_QPEN(d->errorBarsPen);
 	writer->writeAttribute( "opacity", QString::number(d->errorBarsOpacity) );
 	writer->writeEndElement();
 
 	writer->writeEndElement(); //close "xyCurve" section
 }
 
 //! Load from XML
 bool XYCurve::load(XmlStreamReader* reader, bool preview) {
 	Q_D(XYCurve);
 
 	if (!reader->isStartElement() || reader->name() != "xyCurve") {
 		reader->raiseError(i18n("no xy-curve element found"));
 		return false;
 	}
 
 	if (!readBasicAttributes(reader))
 		return false;
 
 	QString attributeWarning = i18n("Attribute '%1' missing or empty, default value is used");
 	QXmlStreamAttributes attribs;
 	QString str;
 
 	while (!reader->atEnd()) {
 		reader->readNext();
 		if (reader->isEndElement() && reader->name() == "xyCurve")
 			break;
 
 		if (!reader->isStartElement())
 			continue;
 
 		if (reader->name() == "comment") {
 			if (!readCommentElement(reader)) return false;
 		} else if (reader->name() == "general") {
 			attribs = reader->attributes();
 			READ_COLUMN(xColumn);
 			READ_COLUMN(yColumn);
 
 			str = attribs.value("visible").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("'visible'"));
 			else
 				d->setVisible(str.toInt());
 		} else if (!preview && reader->name() == "lines") {
 			attribs = reader->attributes();
 
 			READ_INT_VALUE("type", lineType, XYCurve::LineType);
 			READ_INT_VALUE("skipGaps", lineSkipGaps, int);
 			READ_INT_VALUE("interpolationPointsCount", lineInterpolationPointsCount, int);
 			READ_QPEN(d->linePen);
 			READ_DOUBLE_VALUE("opacity", lineOpacity);
 		} else if (!preview && reader->name() == "dropLines") {
 			attribs = reader->attributes();
 
 			READ_INT_VALUE("type", dropLineType, XYCurve::DropLineType);
 			READ_QPEN(d->dropLinePen);
 			READ_DOUBLE_VALUE("opacity", dropLineOpacity);
 
 		} else if (!preview && reader->name() == "symbols") {
 			attribs = reader->attributes();
 
 			READ_INT_VALUE("symbolsStyle", symbolsStyle, Symbol::Style);
 			READ_DOUBLE_VALUE("opacity", symbolsOpacity);
 			READ_DOUBLE_VALUE("rotation", symbolsRotationAngle);
 			READ_DOUBLE_VALUE("size", symbolsSize);
 
 			READ_QBRUSH(d->symbolsBrush);
 			READ_QPEN(d->symbolsPen);
 		} else if (!preview && reader->name() == "values") {
 			attribs = reader->attributes();
 
 			READ_INT_VALUE("type", valuesType, XYCurve::ValuesType);
 			READ_COLUMN(valuesColumn);
 
 			READ_INT_VALUE("position", valuesPosition, XYCurve::ValuesPosition);
 			READ_DOUBLE_VALUE("distance", valuesDistance);
 			READ_DOUBLE_VALUE("rotation", valuesRotationAngle);
 			READ_DOUBLE_VALUE("opacity", valuesOpacity);
 
 			//don't produce any warning if no prefix or suffix is set (empty string is allowd here in xml)
 			d->valuesPrefix = attribs.value("prefix").toString();
 			d->valuesSuffix = attribs.value("suffix").toString();
 
 			READ_QCOLOR(d->valuesColor);
 			READ_QFONT(d->valuesFont);
 		} else if (!preview && reader->name() == "filling") {
 			attribs = reader->attributes();
 
 			READ_INT_VALUE("position", fillingPosition, XYCurve::FillingPosition);
 			READ_INT_VALUE("type", fillingType, PlotArea::BackgroundType);
 			READ_INT_VALUE("colorStyle", fillingColorStyle, PlotArea::BackgroundColorStyle);
 			READ_INT_VALUE("imageStyle", fillingImageStyle, PlotArea::BackgroundImageStyle );
 			READ_INT_VALUE("brushStyle", fillingBrushStyle, Qt::BrushStyle);
 
 			str = attribs.value("firstColor_r").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("firstColor_r"));
 			else
 				d->fillingFirstColor.setRed(str.toInt());
 
 			str = attribs.value("firstColor_g").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("firstColor_g"));
 			else
 				d->fillingFirstColor.setGreen(str.toInt());
 
 			str = attribs.value("firstColor_b").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("firstColor_b"));
 			else
 				d->fillingFirstColor.setBlue(str.toInt());
 
 			str = attribs.value("secondColor_r").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("secondColor_r"));
 			else
 				d->fillingSecondColor.setRed(str.toInt());
 
 			str = attribs.value("secondColor_g").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("secondColor_g"));
 			else
 				d->fillingSecondColor.setGreen(str.toInt());
 
 			str = attribs.value("secondColor_b").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.arg("secondColor_b"));
 			else
 				d->fillingSecondColor.setBlue(str.toInt());
 
 			READ_STRING_VALUE("fileName", fillingFileName);
 			READ_DOUBLE_VALUE("opacity", fillingOpacity);
 		} else if (!preview && reader->name() == "errorBars") {
 			attribs = reader->attributes();
 
 			READ_INT_VALUE("xErrorType", xErrorType, XYCurve::ErrorType);
 			READ_COLUMN(xErrorPlusColumn);
 			READ_COLUMN(xErrorMinusColumn);
 
 			READ_INT_VALUE("yErrorType", yErrorType, XYCurve::ErrorType);
 			READ_COLUMN(yErrorPlusColumn);
 			READ_COLUMN(yErrorMinusColumn);
 
 			READ_INT_VALUE("type", errorBarsType, XYCurve::ErrorBarsType);
 			READ_DOUBLE_VALUE("capSize", errorBarsCapSize);
 
 			READ_QPEN(d->errorBarsPen);
 
 			READ_DOUBLE_VALUE("opacity", errorBarsOpacity);
 		}
 	}
 
 	return true;
 }
 
 //##############################################################################
 //#########################  Theme management ##################################
 //##############################################################################
 void XYCurve::loadThemeConfig(const KConfig& config) {
 	KConfigGroup group = config.group("XYCurve");
 
 	int index = parentAspect()->indexOfChild<XYCurve>(this);
 	const CartesianPlot* plot = dynamic_cast<const CartesianPlot*>(parentAspect());
 	QColor themeColor;
 	if (index<plot->themeColorPalette().size())
 		themeColor = plot->themeColorPalette().at(index);
 	else {
 		if (plot->themeColorPalette().size())
 			themeColor = plot->themeColorPalette().last();
 	}
 
 	QPen p;
 
 	Q_D(XYCurve);
 	d->m_suppressRecalc = true;
 
 	//Line
 	p.setStyle((Qt::PenStyle)group.readEntry("LineStyle", (int)this->linePen().style()));
 	p.setWidthF(group.readEntry("LineWidth", this->linePen().widthF()));
 	p.setColor(themeColor);
 	this->setLinePen(p);
 	this->setLineOpacity(group.readEntry("LineOpacity", this->lineOpacity()));
 
 	//Drop line
 	p.setStyle((Qt::PenStyle)group.readEntry("DropLineStyle",(int) this->dropLinePen().style()));
 	p.setWidthF(group.readEntry("DropLineWidth", this->dropLinePen().widthF()));
 	p.setColor(themeColor);
 	this->setDropLinePen(p);
 	this->setDropLineOpacity(group.readEntry("DropLineOpacity", this->dropLineOpacity()));
 
 	//Symbol
 	this->setSymbolsOpacity(group.readEntry("SymbolOpacity", this->symbolsOpacity()));
 	QBrush brush = symbolsBrush();
 	brush.setColor(themeColor);
 	this->setSymbolsBrush(brush);
 	p = symbolsPen();
 	p.setColor(themeColor);
 	this->setSymbolsPen(p);
 
 	//Values
 	this->setValuesOpacity(group.readEntry("ValuesOpacity", this->valuesOpacity()));
 	this->setValuesColor(group.readEntry("ValuesColor", this->valuesColor()));
 
 	//Filling
 	this->setFillingBrushStyle((Qt::BrushStyle)group.readEntry("FillingBrushStyle",(int) this->fillingBrushStyle()));
 	this->setFillingColorStyle((PlotArea::BackgroundColorStyle)group.readEntry("FillingColorStyle",(int) this->fillingColorStyle()));
 	this->setFillingOpacity(group.readEntry("FillingOpacity", this->fillingOpacity()));
 	this->setFillingPosition((XYCurve::FillingPosition)group.readEntry("FillingPosition",(int) this->fillingPosition()));
 	this->setFillingSecondColor(group.readEntry("FillingSecondColor",(QColor) this->fillingSecondColor()));
 	this->setFillingFirstColor(themeColor);
 	this->setFillingType((PlotArea::BackgroundType)group.readEntry("FillingType",(int) this->fillingType()));
 
 	//Error Bars
 	p.setStyle((Qt::PenStyle)group.readEntry("ErrorBarsStyle",(int) this->errorBarsPen().style()));
 	p.setWidthF(group.readEntry("ErrorBarsWidth", this->errorBarsPen().widthF()));
 	p.setColor(themeColor);
 	this->setErrorBarsPen(p);
 	this->setErrorBarsOpacity(group.readEntry("ErrorBarsOpacity",this->errorBarsOpacity()));
 
 	d->m_suppressRecalc = false;
 	d->recalcShapeAndBoundingRect();
 }
 
 void XYCurve::saveThemeConfig(const KConfig& config) {
 	KConfigGroup group = config.group("XYCurve");
 
 	//Drop line
 	group.writeEntry("DropLineColor",(QColor) this->dropLinePen().color());
 	group.writeEntry("DropLineStyle",(int) this->dropLinePen().style());
 	group.writeEntry("DropLineWidth", this->dropLinePen().widthF());
 	group.writeEntry("DropLineOpacity",this->dropLineOpacity());
 
 	//Error Bars
 	group.writeEntry("ErrorBarsCapSize",this->errorBarsCapSize());
 	group.writeEntry("ErrorBarsOpacity",this->errorBarsOpacity());
 	group.writeEntry("ErrorBarsColor",(QColor) this->errorBarsPen().color());
 	group.writeEntry("ErrorBarsStyle",(int) this->errorBarsPen().style());
 	group.writeEntry("ErrorBarsWidth", this->errorBarsPen().widthF());
 
 	//Filling
 	group.writeEntry("FillingBrushStyle",(int) this->fillingBrushStyle());
 	group.writeEntry("FillingColorStyle",(int) this->fillingColorStyle());
 	group.writeEntry("FillingOpacity", this->fillingOpacity());
 	group.writeEntry("FillingPosition",(int) this->fillingPosition());
 	group.writeEntry("FillingSecondColor",(QColor) this->fillingSecondColor());
 	group.writeEntry("FillingType",(int) this->fillingType());
 
 	//Line
 	group.writeEntry("LineOpacity", this->lineOpacity());
 	group.writeEntry("LineStyle",(int) this->linePen().style());
 	group.writeEntry("LineWidth", this->linePen().widthF());
 
 	//Symbol
 	group.writeEntry("SymbolOpacity", this->symbolsOpacity());
 
 	//Values
 	group.writeEntry("ValuesOpacity", this->valuesOpacity());
 	group.writeEntry("ValuesColor", (QColor) this->valuesColor());
 	group.writeEntry("ValuesFont", this->valuesFont());
 
 	int index = parentAspect()->indexOfChild<XYCurve>(this);
 	if(index<5) {
 		KConfigGroup themeGroup = config.group("Theme");
 		for(int i = index; i<5; i++) {
 			QString s = "ThemePaletteColor" + QString::number(i+1);
 			themeGroup.writeEntry(s,(QColor) this->linePen().color());
 		}
 	}
 }