profile: render profile on desktop via QtQuick

This breaks all dynamic features, including animations,
zooming tooltips, planner-handles, etc. They will have to be
converted one-by-one to QtQuick, which will be a major pain,
as the ProfileView is destroyed by Qt6 on reparenting.
This means that the view cannot store any persistent state.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

CMakeLists.txt

@@ -395,9 +395,9 @@ if (NOT SUBSURFACE_TARGET_EXECUTABLE MATCHES "DownloaderExecutable")
 			qt_add_resources(SUBSURFACE_RESOURCES map-widget/qml/map-widget.qrc)
 			set(SUBSURFACE_MAPWIDGET subsurface_mapwidget)
 		endif()
-		qt_add_resources(SUBSURFACE_RESOURCES subsurface.qrc profile.qrc stats/statsicons.qrc desktop-widgets/qml/statsview2.qrc)
+		qt_add_resources(SUBSURFACE_RESOURCES subsurface.qrc profile.qrc stats/statsicons.qrc desktop-widgets/qml/statsview2.qrc desktop-widgets/qml/profileview.qrc)
 	else()
-		qt5_add_resources(SUBSURFACE_RESOURCES subsurface.qrc profile.qrc stats/statsicons.qrc map-widget/qml/map-widget.qrc desktop-widgets/qml/statsview2.qrc)
+		qt5_add_resources(SUBSURFACE_RESOURCES subsurface.qrc profile.qrc stats/statsicons.qrc map-widget/qml/map-widget.qrc desktop-widgets/qml/statsview2.qrc desktop-widgets/qml/profileview.qrc)
 		set(SUBSURFACE_MAPWIDGET subsurface_mapwidget)
 	endif()
 endif()

Subsurface-mobile.pro

@@ -184,7 +184,8 @@ SOURCES += subsurface-mobile-main.cpp \
 	profile-widget/tankitem.cpp \
 	profile-widget/divelineitem.cpp \
 	profile-widget/diverectitem.cpp \
-	profile-widget/divetextitem.cpp
+	profile-widget/divetextitem.cpp \
+	profile-widget/profileview.cpp
 
 HEADERS += \
 	commands/command_base.h \
@@ -349,7 +350,8 @@ HEADERS += \
 	profile-widget/divepixmapcache.h \
 	profile-widget/divepixmapitem.h \
 	profile-widget/diverectitem.h \
-	profile-widget/divetextitem.h
+	profile-widget/divetextitem.h \
+	profile-widget/profileview.h
 
 RESOURCES += mobile-widgets/qml/mobile-resources.qrc \
 		mobile-widgets/3rdparty/icons.qrc \

desktop-widgets/divelogexportdialog.cpp

@@ -22,7 +22,6 @@
 #include "desktop-widgets/divelogexportdialog.h"
 #include "desktop-widgets/diveshareexportdialog.h"
 #include "desktop-widgets/subsurfacewebservices.h"
-#include "profile-widget/profilewidget2.h"
 
 // Retrieves the current unit settings defined in the Subsurface preferences.
 #define GET_UNIT(name, field, f, t)           \

desktop-widgets/mainwindow.cpp

@@ -57,7 +57,6 @@
 #include "commands/command.h"
 
 #include "profilewidget.h"
-#include "profile-widget/profilewidget2.h"
 
 #ifndef NO_PRINTING
 #include "desktop-widgets/printdialog.h"

desktop-widgets/modeldelegates.cpp

@@ -8,7 +8,6 @@
 #include "qt-models/cylindermodel.h"
 #include "qt-models/models.h"
 #include "desktop-widgets/starwidget.h"
-#include "profile-widget/profilewidget2.h"
 #include "qt-models/tankinfomodel.h"
 #include "qt-models/weightsysteminfomodel.h"
 #include "qt-models/weightmodel.h"

desktop-widgets/profilewidget.cpp

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
 #include "profilewidget.h"
-#include "profile-widget/profilewidget2.h"
+#include "profile-widget/profileview.h"
 #include "commands/command.h"
 #include "core/color.h"
 #include "core/event.h"
@@ -14,6 +14,8 @@
 
 #include <QToolBar>
 #include <QHBoxLayout>
+#include <QQmlEngine>
+#include <QQuickWidget>
 #include <QStackedWidget>
 #include <QLabel>
 
@@ -54,6 +56,7 @@ void EmptyView::resizeEvent(QResizeEvent *)
 	update();
 }
 
+static const QUrl urlProfileView = QUrl(QStringLiteral("qrc:/qml/profileview.qml"));
 ProfileWidget::ProfileWidget() : d(nullptr), dc(0), placingCommand(false)
 {
 	ui.setupUi(this);
@@ -74,7 +77,10 @@ ProfileWidget::ProfileWidget() : d(nullptr), dc(0), placingCommand(false)
 
 	emptyView.reset(new EmptyView);
 
-	view.reset(new ProfileWidget2(DivePlannerPointsModel::instance(), 1.0, this));
+	viewWidget.reset(new QQuickWidget);
+	viewWidget->setSource(urlProfileView);
+	viewWidget->setResizeMode(QQuickWidget::SizeRootObjectToView);
+
 	QToolBar *toolBar = new QToolBar(this);
 	for (QAction *a: toolbarActions)
 		toolBar->addAction(a);
@@ -83,7 +89,7 @@ ProfileWidget::ProfileWidget() : d(nullptr), dc(0), placingCommand(false)
 
 	stack = new QStackedWidget(this);
 	stack->addWidget(emptyView.get());
-	stack->addWidget(view.get());
+	stack->addWidget(viewWidget.get());
 
 	QHBoxLayout *layout = new QHBoxLayout(this);
 	layout->setSpacing(0);
@@ -123,14 +129,6 @@ ProfileWidget::ProfileWidget() : d(nullptr), dc(0), placingCommand(false)
 	connect(ui.profPO2, &QAction::triggered, pp_gas, &qPrefPartialPressureGas::set_po2);
 
 	connect(&diveListNotifier, &DiveListNotifier::divesChanged, this, &ProfileWidget::divesChanged);
-	connect(&diveListNotifier, &DiveListNotifier::settingsChanged, view.get(), &ProfileWidget2::settingsChanged);
-	connect(&diveListNotifier, &DiveListNotifier::cylinderAdded, this, &ProfileWidget::cylindersChanged);
-	connect(&diveListNotifier, &DiveListNotifier::cylinderRemoved, this, &ProfileWidget::cylindersChanged);
-	connect(&diveListNotifier, &DiveListNotifier::cylinderEdited, this, &ProfileWidget::cylindersChanged);
-	connect(view.get(), &ProfileWidget2::stopAdded, this, &ProfileWidget::stopAdded);
-	connect(view.get(), &ProfileWidget2::stopRemoved, this, &ProfileWidget::stopRemoved);
-	connect(view.get(), &ProfileWidget2::stopMoved, this, &ProfileWidget::stopMoved);
-	connect(view.get(), &ProfileWidget2::stopEdited, this, &ProfileWidget::stopEdited);
 
 	ui.profCalcAllTissues->setChecked(qPrefTechnicalDetails::calcalltissues());
 	ui.profCalcCeiling->setChecked(qPrefTechnicalDetails::calcceiling());
@@ -151,12 +149,38 @@ ProfileWidget::ProfileWidget() : d(nullptr), dc(0), placingCommand(false)
 	ui.profTissues->setChecked(qPrefTechnicalDetails::percentagegraph());
 	ui.profScaled->setChecked(qPrefTechnicalDetails::zoomed_plot());
 	ui.profInfobox->setChecked(qPrefTechnicalDetails::infobox());
+
+	//connect(&diveListNotifier, &DiveListNotifier::settingsChanged, view.get(), &ProfileWidget2::settingsChanged);
+	//connect(&diveListNotifier, &DiveListNotifier::cylinderAdded, this, &ProfileWidget::cylindersChanged);
+	//connect(&diveListNotifier, &DiveListNotifier::cylinderRemoved, this, &ProfileWidget::cylindersChanged);
+	//connect(&diveListNotifier, &DiveListNotifier::cylinderEdited, this, &ProfileWidget::cylindersChanged);
+	//connect(view.get(), &ProfileWidget2::stopAdded, this, &ProfileWidget::stopAdded);
+	//connect(view.get(), &ProfileWidget2::stopRemoved, this, &ProfileWidget::stopRemoved);
+	//connect(view.get(), &ProfileWidget2::stopMoved, this, &ProfileWidget::stopMoved);
+	//connect(view.get(), &ProfileWidget2::stopEdited, this, &ProfileWidget::stopEdited);
 }
 
 ProfileWidget::~ProfileWidget()
 {
 }
 
+// hack around the Qt6 bug where the QML object gets destroyed and recreated
+ProfileView *ProfileWidget::getView()
+{
+	ProfileView *view = qobject_cast<ProfileView *>(viewWidget->rootObject());
+	if (!view)
+		qWarning("Oops. The root of the StatsView is not a StatsView.");
+	if (view) {
+		// try to prevent the JS garbage collection from freeing the object
+		// this appears to fail with Qt6 which is why we still look up the
+		// object from the rootObject
+		viewWidget->engine()->setObjectOwnership(view, QQmlEngine::CppOwnership);
+		view->setParent(this);
+		view->setVisible(isVisible()); // Synchronize visibility of widget and QtQuick-view.
+	}
+	return view;
+}
+
 void ProfileWidget::setEnabledToolbar(bool enabled)
 {
 	for (QAction *b: toolbarActions)
@@ -224,13 +248,14 @@ void ProfileWidget::plotDive(dive *dIn, int dcIn)
 			editDive();
 	}
 
+	auto view = getView();
 	setEnabledToolbar(d != nullptr);
 	if (editedDive) {
 		view->plotDive(editedDive.get(), dc);
 		setDive(editedDive.get(), dc);
 	} else if (d) {
-		view->setProfileState(d, dc);
+		//view->setProfileState(d, dc);
-		view->resetZoom(); // when switching dive, reset the zoomLevel
+		//view->resetZoom(); // when switching dive, reset the zoomLevel
 		view->plotDive(d, dc);
 		setDive(d, dc);
 	} else {
@@ -273,7 +298,7 @@ void ProfileWidget::divesChanged(const QVector<dive *> &dives, DiveField field)
 		return;
 
 	// If we're editing the current dive and not currently
-	// placing command, we have to update the edited dive.
+	// placing a command, we have to update the edited dive.
 	if (editedDive) {
 		copy_dive(d, editedDive.get());
 		// TODO: Holy moly that function sends too many signals. Fix it!
@@ -307,7 +332,7 @@ void ProfileWidget::cylindersChanged(struct dive *changed, int pos)
 void ProfileWidget::setPlanState(const struct dive *d, int dcNr)
 {
 	dc = dcNr;
-	view->setPlanState(d, dcNr);
+	//view->setPlanState(d, dcNr);
 	setDive(d, dcNr);
 }
 
@@ -329,7 +354,7 @@ void ProfileWidget::editDive()
 	copy_dive(d, editedDive.get()); // Work on a copy of the dive
 	DivePlannerPointsModel::instance()->setPlanMode(DivePlannerPointsModel::EDIT);
 	DivePlannerPointsModel::instance()->loadFromDive(editedDive.get(), dc);
-	view->setEditState(editedDive.get(), dc);
+	//view->setEditState(editedDive.get(), dc);
 }
 
 void ProfileWidget::exitEditMode()
@@ -338,7 +363,7 @@ void ProfileWidget::exitEditMode()
 		return;
 
 	DivePlannerPointsModel::instance()->setPlanMode(DivePlannerPointsModel::NOTHING);
-	view->setProfileState(d, dc); // switch back to original dive before erasing the copy.
+	//view->setProfileState(d, dc); // switch back to original dive before erasing the copy.
 	editedDive.reset();
 }
 

desktop-widgets/profilewidget.h

@@ -10,8 +10,9 @@
 #include <vector>
 
 struct dive;
-class ProfileWidget2;
+class ProfileView;
 class EmptyView;
+class QQuickWidget;
 class QStackedWidget;
 
 class ProfileWidget : public QWidget {
@@ -19,7 +20,6 @@ class ProfileWidget : public QWidget {
 public:
 	ProfileWidget();
 	~ProfileWidget();
-	std::unique_ptr<ProfileWidget2> view;
 	void plotDive(struct dive *d, int dc); // Attempt to keep DC number id dc < 0
 	void plotCurrentDive();
 	void setPlanState(const struct dive *d, int dc);
@@ -40,6 +40,8 @@ slots:
 	void stopMoved(int count);
 	void stopEdited();
 private:
+	ProfileView *getView();
+	std::unique_ptr<QQuickWidget> viewWidget;
 	std::unique_ptr<EmptyView> emptyView;
 	std::vector<QAction *> toolbarActions;
 	Ui::ProfileWidget ui;

desktop-widgets/qml/profileview.qml

@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0
+import org.subsurfacedivelog.mobile 1.0
+
+ProfileView {
+	property real dpr: 1.0
+}

desktop-widgets/qml/profileview.qrc

@@ -0,0 +1,5 @@
+<RCC>
+	<qresource prefix="/qml">
+		<file>profileview.qml</file>
+	</qresource>
+</RCC>

desktop-widgets/simplewidgets.cpp

@@ -19,7 +19,6 @@
 #include "libdivecomputer/parser.h"
 #include "desktop-widgets/divelistview.h"
 #include "core/selection.h"
-#include "profile-widget/profilewidget2.h"
 #include "commands/command.h"
 #include "core/metadata.h"
 #include "core/range.h"

desktop-widgets/tab-widgets/TabDiveInformation.cpp

@@ -2,7 +2,6 @@
 #include "TabDiveInformation.h"
 #include "maintab.h"
 #include "ui_TabDiveInformation.h"
-#include "profile-widget/profilewidget2.h"
 #include "../tagwidget.h"
 #include "commands/command.h"
 #include "core/subsurface-string.h"

profile-widget/CMakeLists.txt

@@ -24,6 +24,8 @@ set(SUBSURFACE_PROFILE_LIB_SRCS
 	divetooltipitem.h
 	profilescene.cpp
 	profilescene.h
+	profileview.cpp
+	profileview.h
 	tankitem.cpp
 	tankitem.h
 )
@@ -38,8 +40,6 @@ set(SUBSURFACE_PROFILE_LIB_SRCS
 	${SUBSURFACE_PROFILE_LIB_SRCS}
 	divehandler.cpp
 	divehandler.h
-	profilewidget2.cpp
-	profilewidget2.h
 	ruleritem.cpp
 	ruleritem.h
 )

profile-widget/divehandler.cpp

@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "divehandler.h"
-#include "profilewidget2.h"
 #include "profilescene.h"
 #include "core/dive.h"
 #include "core/gettextfromc.h"
@@ -22,8 +21,9 @@ DiveHandler::DiveHandler(const struct dive *d, int currentDcNr) : dive(d), dcNr(
 
 int DiveHandler::parentIndex()
 {
-	ProfileWidget2 *view = qobject_cast<ProfileWidget2 *>(scene()->views().first());
+	//ProfileWidget2 *view = qobject_cast<ProfileWidget2 *>(scene()->views().first());
-	return view->handleIndex(this);
+	//return view->handleIndex(this);
+	return 0; // FIXME
 }
 
 void DiveHandler::contextMenuEvent(QGraphicsSceneContextMenuEvent *event)
@@ -54,19 +54,17 @@ void DiveHandler::contextMenuEvent(QGraphicsSceneContextMenuEvent *event)
 
 void DiveHandler::selfRemove()
 {
-#ifndef SUBSURFACE_MOBILE
 	setSelected(true);
-	ProfileWidget2 *view = qobject_cast<ProfileWidget2 *>(scene()->views().first());
+	//ProfileWidget2 *view = qobject_cast<ProfileWidget2 *>(scene()->views().first());
-	view->keyDeleteAction();
+	//view->keyDeleteAction();
-#endif
 }
 
 void DiveHandler::changeGas()
 {
-	ProfileWidget2 *view = qobject_cast<ProfileWidget2 *>(scene()->views().first());
+	//ProfileWidget2 *view = qobject_cast<ProfileWidget2 *>(scene()->views().first());
-	QAction *action = qobject_cast<QAction *>(sender());
+	//QAction *action = qobject_cast<QAction *>(sender());
 
-	view->changeGas(parentIndex(), action->data().toInt());
+	//view->changeGas(parentIndex(), action->data().toInt());
 }
 
 void DiveHandler::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
@@ -75,9 +73,9 @@ void DiveHandler::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
 		return;
 	t.start();
 
-	ProfileWidget2 *view = qobject_cast<ProfileWidget2*>(scene()->views().first());
+	//ProfileWidget2 *view = qobject_cast<ProfileWidget2*>(scene()->views().first());
-	if(!view->profileScene->pointOnProfile(event->scenePos()))
+	//if(!view->profileScene->pointOnProfile(event->scenePos()))
-		return;
+		//return;
 
 	QGraphicsEllipseItem::mouseMoveEvent(event);
 	emit moved();

profile-widget/diveprofileitem.cpp

@@ -3,13 +3,15 @@
 #include "profile-widget/divecartesianaxis.h"
 #include "profile-widget/divetextitem.h"
 #include "profile-widget/animationfunctions.h"
+#include "core/dive.h"
 #include "core/profile.h"
-#include "qt-models/diveplannermodel.h"
 #include "core/qthelper.h"
 #include "core/settings/qPrefTechnicalDetails.h"
 #include "core/settings/qPrefLog.h"
 #include "libdivecomputer/parser.h"
-#include "profile-widget/profilewidget2.h"
+#include "qt-models/diveplannermodel.h"
+
+#include <QPainter>
 
 AbstractProfilePolygonItem::AbstractProfilePolygonItem(const plot_info &pInfo, const DiveCartesianAxis &horizontal,
 						       const DiveCartesianAxis &vertical, DataAccessor accessor,

profile-widget/divetextitem.cpp

@@ -1,11 +1,12 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "divetextitem.h"
-#include "profilewidget2.h"
 #include "core/color.h"
 #include "core/errorhelper.h"
 
-#include <QBrush>
+#include <cmath>
 #include <QApplication>
+#include <QBrush>
+#include <QPainter>
 
 static const double outlineSize = 3.0;
 

profile-widget/profilescene.cpp

@@ -465,6 +465,10 @@ void ProfileScene::plotDive(const struct dive *dIn, int dcIn, DivePlannerPointsM
 	updateVisibility(hasHeartBeat, simplified);
 	updateAxes(hasHeartBeat, simplified);
 
+	// When we found that we don't have enough place to draw, the state was set to empty.
+	if (empty)
+		return;
+
 	int newMaxtime = get_maxtime(plotInfo);
 	if (calcMax || newMaxtime > maxtime)
 		maxtime = newMaxtime;

profile-widget/profileview.cpp

@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "profileview.h"
+#include "profilescene.h"
+#include "zvalues.h"
+#include "core/dive.h"
+#include "core/errorhelper.h"
+#include "core/pref.h"
+#include "core/settings/qPrefTechnicalDetails.h"
+#include "qt-quick/chartitem.h"
+
+#include <QDebug>
+#include <QElapsedTimer>
+
+static double calcZoom(int zoomLevel)
+{
+	// Base of exponential zoom function: one wheel-click will increase the zoom by 15%.
+	constexpr double zoomFactor = 1.15;
+	return zoomLevel == 0 ? 1.0 : pow(zoomFactor, zoomLevel);
+}
+
+ProfileView::ProfileView(QQuickItem *parent) : ChartView(parent, ProfileZValue::Count),
+	d(nullptr),
+	dc(0),
+	zoomLevel(0),
+	zoomedPosition(0.0),
+	empty(true),
+	shouldCalculateMax(true),
+	profileScene(std::make_unique<ProfileScene>(1.0, false, false))
+{
+	setBackgroundColor(Qt::black);
+	setFlag(ItemHasContents, true);
+
+	setAcceptHoverEvents(true);
+	setAcceptedMouseButtons(Qt::LeftButton);
+}
+
+ProfileView::ProfileView() : ProfileView(nullptr)
+{
+}
+
+ProfileView::~ProfileView()
+{
+}
+
+void ProfileView::resetPointers()
+{
+	profileItem.reset();
+}
+
+void ProfileView::plotAreaChanged(const QSizeF &s)
+{
+	if (!empty)
+		plotDive(d, dc, RenderFlags::Instant);
+}
+
+void ProfileView::clear()
+{
+	//clearPictures();
+	//disconnectPlannerConnections();
+	profileScene->clear();
+	//handles.clear();
+	//gases.clear();
+	empty = true;
+	d = nullptr;
+	dc = 0;
+}
+
+void ProfileView::plotDive(const struct dive *dIn, int dcIn, int flags)
+{
+	d = dIn;
+	dc = dcIn;
+	if (!d) {
+		clear();
+		return;
+	}
+
+	// If there was no previously displayed dive, turn off animations
+	if (empty)
+		flags |= RenderFlags::Instant;
+	empty = false;
+
+	// If Qt decided to destroy our canvas, recreate it
+	if (!profileItem)
+		profileItem = createChartItem<ChartGraphicsSceneItem>(ProfileZValue::Profile);
+
+	profileItem->setPos(QPointF(0.0, 0.0));
+
+	QElapsedTimer measureDuration; // let's measure how long this takes us (maybe we'll turn of TTL calculation later
+	measureDuration.start();
+
+	//DivePlannerPointsModel *model = currentState == EDIT || currentState == PLAN ? plannerModel : nullptr;
+	DivePlannerPointsModel *model = nullptr;
+	bool inPlanner = flags & RenderFlags::PlanMode;
+
+	QColor backgroundColor = inPlanner ? QColor("#D7E3EF")
+					   : getColor(::BACKGROUND, false);
+
+	double zoom = calcZoom(zoomLevel);
+
+	profileScene->resize(size());
+	profileScene->plotDive(d, dc, model, inPlanner, true, //flags & RenderFlags::Instant,
+			       flags & RenderFlags::DontRecalculatePlotInfo,
+			       shouldCalculateMax, zoom, zoomedPosition);
+	profileItem->draw(size(), backgroundColor, *profileScene);
+
+	//rulerItem->setVisible(prefs.rulergraph && currentState != PLAN && currentState != EDIT);
+	//toolTipItem->setPlotInfo(profileScene->plotInfo);
+	//rulerItem->setPlotInfo(d, profileScene->plotInfo);
+
+	//if ((currentState == EDIT || currentState == PLAN) && plannerModel) {
+		//repositionDiveHandlers();
+		//plannerModel->deleteTemporaryPlan();
+	//}
+
+	// On zoom / pan don't recreate the picture thumbnails, only change their position.
+	//if (flags & RenderFlags::DontRecalculatePlotInfo)
+		//updateThumbnails();
+	//else
+		//plotPicturesInternal(d, flags & RenderFlags::Instant);
+
+	//toolTipItem->refresh(d, mapToScene(mapFromGlobal(QCursor::pos())), currentState == PLAN);
+
+	update();
+
+	// OK, how long did this take us? Anything above the second is way too long,
+	// so if we are calculation TTS / NDL then let's force that off.
+	qint64 elapsedTime = measureDuration.elapsed();
+	if (verbose)
+		qDebug() << "Profile calculation for dive " << d->number << "took" << elapsedTime << "ms" << " -- calculated ceiling preference is" << prefs.calcceiling;
+	if (elapsedTime > 1000 && prefs.calcndltts) {
+		qPrefTechnicalDetails::set_calcndltts(false);
+		report_error("%s", qPrintable(tr("Show NDL / TTS was disabled because of excessive processing time")));
+	}
+}

profile-widget/profileview.h

@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef PROFILE_VIEW_H
+#define PROFILE_VIEW_H
+
+#include "qt-quick/chartview.h"
+#include <memory>
+
+class ChartGraphicsSceneItem;
+class ProfileScene;
+
+class ProfileView : public ChartView {
+	Q_OBJECT
+public:
+	ProfileView();
+	ProfileView(QQuickItem *parent);
+	~ProfileView();
+
+	struct RenderFlags {
+		static constexpr int None = 0;
+		static constexpr int Instant = 1 << 0;
+		static constexpr int DontRecalculatePlotInfo = 1 << 1;
+		static constexpr int EditMode = 1 << 2;
+		static constexpr int PlanMode = 1 << 3;
+	};
+
+	void plotDive(const struct dive *d, int dc, int flags = RenderFlags::None);
+	void clear();
+private:
+	const struct dive *d;
+	int dc;
+	int zoomLevel;
+	double zoomedPosition;	// Position when zoomed: 0.0 = beginning, 1.0 = end.
+	bool empty; // No dive shown.
+	bool shouldCalculateMax; // Calculate maximum time and depth (default). False when dragging handles.
+	std::unique_ptr<ProfileScene> profileScene;
+	ChartItemPtr<ChartGraphicsSceneItem> profileItem;
+
+	void plotAreaChanged(const QSizeF &size) override;
+	void resetPointers() override;
+};
+
+#endif

profile-widget/profilewidget2.cpp

@@ -1,5 +1,4 @@
 // SPDX-License-Identifier: GPL-2.0
-#include "profile-widget/profilewidget2.h"
 #include "profile-widget/profilescene.h"
 #include "core/device.h"
 #include "core/event.h"
@@ -398,21 +397,6 @@ static void hideAll(const T &container)
 		item->setVisible(false);
 }
 
-void ProfileWidget2::clear()
-{
-	currentState = INIT;
-#ifndef SUBSURFACE_MOBILE
-	clearPictures();
-#endif
-	disconnectPlannerModel();
-	profileScene->clear();
-	handles.clear();
-	gases.clear();
-	empty = true;
-	d = nullptr;
-	dc = 0;
-}
-
 void ProfileWidget2::setProfileState(const dive *dIn, int dcIn)
 {
 	d = dIn;

profile-widget/profilewidget2.h

@@ -60,7 +60,6 @@ public:
 #ifndef SUBSURFACE_MOBILE
 	bool eventFilter(QObject *, QEvent *) override;
 #endif
-	std::unique_ptr<ProfileScene> profileScene;
 	State currentState;
 
 signals:

profile-widget/ruleritem.cpp

@@ -1,12 +1,15 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "profile-widget/ruleritem.h"
-#include "profile-widget/profilewidget2.h"
 #include "core/settings/qPrefTechnicalDetails.h"
 
-#include <qgraphicssceneevent.h>
-
 #include "core/profile.h"
 
+#include <QFont>
+#include <QFontMetrics>
+#include <QGraphicsScene>
+#include <QGraphicsSceneEvent>
+#include <QGraphicsView>
+
 RulerNodeItem2::RulerNodeItem2() :
 	pInfo(NULL),
 	idx(-1),
@@ -77,18 +80,16 @@ RulerItem2::RulerItem2() : pInfo(NULL),
 	textItemBack->setPen(QColor(Qt::white));
 	textItemBack->setFlag(QGraphicsItem::ItemIgnoresTransformations);
 	setPen(QPen(QColor(Qt::black), 0.0));
-#ifndef SUBSURFACE_MOBILE
 	connect(qPrefTechnicalDetails::instance(), &qPrefTechnicalDetails::rulergraphChanged, this, &RulerItem2::settingsChanged);
-#endif
 }
 
 void RulerItem2::settingsChanged(bool value)
 {
-	ProfileWidget2 *profWidget = NULL;
+	//ProfileWidget2 *profWidget = NULL;
-	if (scene() && scene()->views().count())
+	//if (scene() && scene()->views().count())
-		profWidget = qobject_cast<ProfileWidget2 *>(scene()->views().first());
+		//profWidget = qobject_cast<ProfileWidget2 *>(scene()->views().first());
 
-	setVisible( (profWidget && profWidget->currentState == ProfileWidget2::PROFILE) ? value : false);
+	//setVisible( (profWidget && profWidget->currentState == ProfileWidget2::PROFILE) ? value : false);
 }
 
 void RulerItem2::recalculate()

profile-widget/zvalues.h

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0
+// Defines the z-values of features in the profile view.
+// Objects with higher z-values are painted on top of objects
+// with smaller z-values. For the same z-value objects are
+// drawn in order of addition to the scene.
+#ifndef PROFILE_ZVALUES_H
+#define PROFILE_ZVALUES_H
+
+// Encapsulating an enum in a struct is stupid, but allows us
+// to not poison the namespace and yet autoconvert to int
+// (in constrast to enum class). enum is so broken!
+struct ProfileZValue {
+	enum ZValues {
+		Profile = 0,
+		Count
+	};
+};
+
+#endif

qt-quick/chartitem.cpp

@@ -4,6 +4,7 @@
 #include "chartview.h"
 
 #include <cmath>
+#include <QGraphicsScene>
 #include <QQuickWindow>
 #include <QSGFlatColorMaterial>
 #include <QSGImageNode>
@@ -83,10 +84,15 @@ void ChartPixmapItem::render()
 
 void ChartPixmapItem::resize(QSizeF size)
 {
+	QSize s_int(round_up(size.width()), round_up(size.height()));
+	if (img && s_int == img->size())
+		return;
 	painter.reset();
-	img.reset(new QImage(round_up(size.width()), round_up(size.height()), QImage::Format_ARGB32));
+	img.reset(new QImage(s_int, QImage::Format_ARGB32));
+	if (!img->isNull()) {
 		painter.reset(new QPainter(img.get()));
 		painter->setRenderHint(QPainter::Antialiasing);
+	}
 	rect.setSize(size);
 	setTextureDirty();
 }
@@ -102,6 +108,16 @@ QRectF ChartPixmapItem::getRect() const
 	return rect;
 }
 
+void ChartGraphicsSceneItem::draw(QSizeF s, QColor background, QGraphicsScene &scene)
+{
+	resize(s); // Noop if size doesn't change
+	if (!painter)
+		return;		// Happens if we resize to (0,0)
+	img->fill(background);
+	scene.render(painter.get(), QRect(QPoint(), img->size()), scene.sceneRect(), Qt::IgnoreAspectRatio);
+	setTextureDirty();
+}
+
 ChartRectItem::ChartRectItem(ChartView &v, size_t z,
 			     const QPen &pen, const QBrush &brush, double radius) : ChartPixmapItem(v, z),
 	pen(pen), brush(brush), radius(radius)

qt-quick/chartitem.h

@@ -11,6 +11,7 @@
 #include <QPainter>
 
 class ChartView;
+class QGraphicsScene;
 class QSGGeometry;
 class QSGGeometryNode;
 class QSGFlatColorMaterial;
@@ -74,6 +75,14 @@ private:
 	std::unique_ptr<QSGTexture> texture;
 };
 
+// Renders a QGraphicsScene
+class ChartGraphicsSceneItem : public ChartPixmapItem
+{
+public:
+	using ChartPixmapItem::ChartPixmapItem;
+	void draw(QSizeF s, QColor background, QGraphicsScene &scene);
+};
+
 // Draw a rectangular background after resize. Children are responsible for calling update().
 class ChartRectItem : public ChartPixmapItem {
 public:

subsurface-helper.cpp

@@ -7,6 +7,7 @@
 #include "qt-models/maplocationmodel.h"
 #endif
 
+#include "profile-widget/profileview.h"
 #include "stats/statsview.h"
 #include "core/devicedetails.h"
 #include "core/errorhelper.h"
@@ -229,5 +230,6 @@ static void register_qml_types(QQmlEngine *engine)
 	register_qml_type<MapWidgetHelper>("MapWidgetHelper");
 	register_qml_type<MapLocationModel>("MapLocationModel");
 #endif
+	register_qml_type<ProfileView>("ProfileView");
 	register_qml_type<StatsView>("StatsView");
 }