statistics: make selection keyboard modifiers more general

Up to now, we passed a "shiftPressed" flag to the individual
selection functions. To be more general replace by a struct
with "shift" and "ctrl" flags.

While doing this:
1) Move the struct into a new statsselection file for better
   encapsulation.
2) Change shift to control in the scatter series, since individual
   selection of items is usually done with control, not shift.
   Shift usually means "select range".

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

Subsurface-mobile.pro

@@ -144,6 +144,7 @@ SOURCES += subsurface-mobile-main.cpp \
 	stats/statscolors.cpp \
 	stats/statsgrid.cpp \
 	stats/statshelper.cpp \
+	stats/statsselection.cpp \
 	stats/statsseries.cpp \
 	stats/statsstate.cpp \
 	mobile-widgets/qmlinterface.cpp \
@@ -297,6 +298,7 @@ HEADERS += \
 	stats/statscolors.h \
 	stats/statsgrid.h \
 	stats/statshelper.h \
+	stats/statsselection.h \
 	stats/statsseries.h \
 	stats/statsstate.h \
 	stats/statstranslations.h \

stats/CMakeLists.txt

@@ -36,6 +36,8 @@ set(SUBSURFACE_STATS_SRCS
 	statsgrid.cpp
 	statshelper.h
 	statshelper.cpp
+	statsselection.h
+	statsselection.cpp
 	statsseries.h
 	statsseries.cpp
 	statsstate.h

stats/barseries.cpp

@@ -411,7 +411,7 @@ void BarSeries::unhighlight()
 	highlighted = Index();
 }
 
-bool BarSeries::selectItemsUnderMouse(const QPointF &pos, bool)
+bool BarSeries::selectItemsUnderMouse(const QPointF &pos, SelectionModifier)
 {
 	Index index = getItemUnderMouse(pos);
 	if (index.bar < 0) {

stats/barseries.h

@@ -69,7 +69,7 @@ public:
 	void updatePositions() override;
 	bool hover(QPointF pos) override;
 	void unhighlight() override;
-	bool selectItemsUnderMouse(const QPointF &point, bool shiftPressed) override;
+	bool selectItemsUnderMouse(const QPointF &point, SelectionModifier modifier) override;
 
 private:
 	BarSeries(StatsView &view, StatsAxis *xAxis, StatsAxis *yAxis,

stats/boxseries.cpp

@@ -146,7 +146,7 @@ void BoxSeries::unhighlight()
 	highlighted = -1;
 }
 
-bool BoxSeries::selectItemsUnderMouse(const QPointF &pos, bool)
+bool BoxSeries::selectItemsUnderMouse(const QPointF &pos, SelectionModifier)
 {
 	int index = getItemUnderMouse(pos);
 	if (index < 0) {

stats/boxseries.h

@@ -23,7 +23,7 @@ public:
 	void updatePositions() override;
 	bool hover(QPointF pos) override;
 	void unhighlight() override;
-	bool selectItemsUnderMouse(const QPointF &point, bool shiftPressed) override;
+	bool selectItemsUnderMouse(const QPointF &point, SelectionModifier modifier) override;
 
 	// Note: this expects that all items are added with increasing pos
 	// and that no bar is inside another bar, i.e. lowerBound and upperBound

stats/pieseries.cpp

@@ -266,7 +266,7 @@ void PieSeries::unhighlight()
 	highlighted = -1;
 }
 
-bool PieSeries::selectItemsUnderMouse(const QPointF &pos, bool)
+bool PieSeries::selectItemsUnderMouse(const QPointF &pos, SelectionModifier)
 {
 	int index = getItemUnderMouse(pos);
 	if (index < 0) {

stats/pieseries.h

@@ -28,7 +28,7 @@ public:
 	void updatePositions() override;
 	bool hover(QPointF pos) override;
 	void unhighlight() override;
-	bool selectItemsUnderMouse(const QPointF &point, bool shiftPressed) override;
+	bool selectItemsUnderMouse(const QPointF &point, SelectionModifier modifier) override;
 
 	std::vector<QString> binNames();
 

stats/scatterseries.cpp

@@ -96,12 +96,12 @@ std::vector<int> ScatterSeries::getItemsInRect(const QRectF &rect) const
 	return res;
 }
 
-bool ScatterSeries::selectItemsUnderMouse(const QPointF &point, bool shiftPressed)
+bool ScatterSeries::selectItemsUnderMouse(const QPointF &point, SelectionModifier modifier)
 {
 	std::vector<struct dive *> selected;
 	std::vector<int> indices = getItemsUnderMouse(point);
 
-	if (shiftPressed) {
+	if (modifier.ctrl) {
 		// When shift is pressed, add the items under the mouse to the selection
 		// or, if all items under the mouse are selected, remove them.
 		selected = getDiveSelection();
@@ -141,13 +141,13 @@ bool ScatterSeries::supportsLassoSelection() const
 	return true;
 }
 
-void ScatterSeries::selectItemsInRect(const QRectF &rect, bool shiftPressed, const std::vector<dive *> &oldSelection)
+void ScatterSeries::selectItemsInRect(const QRectF &rect, SelectionModifier modifier, const std::vector<dive *> &oldSelection)
 {
 	std::vector<struct dive *> selected;
 	std::vector<int> indices = getItemsInRect(rect);
 	selected.reserve(oldSelection.size() + indices.size());
 
-	if (shiftPressed) {
+	if (modifier.ctrl) {
 		selected = oldSelection;
 		// Ouch - this primitive merging of the selections grows with O(n^2). Fix this.
 		for (int idx: indices) {

stats/scatterseries.h

@@ -27,9 +27,9 @@ public:
 
 	// Note: this expects that all items are added with increasing pos!
 	void append(dive *d, double pos, double value);
-	bool selectItemsUnderMouse(const QPointF &point, bool shiftPressed) override;
+	bool selectItemsUnderMouse(const QPointF &point, SelectionModifier modifier) override;
 	bool supportsLassoSelection() const override;
-	void selectItemsInRect(const QRectF &rect, bool shiftPressed, const std::vector<dive *> &oldSelection) override;
+	void selectItemsInRect(const QRectF &rect, SelectionModifier modifier, const std::vector<dive *> &oldSelection) override;
 
 private:
 	// Get items under mouse.

stats/statsselection.cpp

@@ -0,0 +1,2 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "statsselection.h"

stats/statsselection.h

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+// Functions and data structures handling dive selections.
+
+#ifndef STATS_SELECTION_H
+#define STATS_SELECTION_H
+
+struct SelectionModifier {
+	unsigned int ctrl : 1;
+	unsigned int shift : 1;
+	// Note: default member initializers for bit-fields becomes available with C++20.
+	// Therefore, for now an inline constructor.
+	SelectionModifier() : ctrl(0), shift(0) {}
+};
+
+#endif

stats/statsseries.cpp

@@ -22,6 +22,6 @@ bool StatsSeries::supportsLassoSelection() const
 	return false;
 }
 
-void StatsSeries::selectItemsInRect(const QRectF &, bool, const std::vector<dive *> &)
+void StatsSeries::selectItemsInRect(const QRectF &, SelectionModifier, const std::vector<dive *> &)
 {
 }

stats/statsseries.h

@@ -4,6 +4,8 @@
 #ifndef STATS_SERIES_H
 #define STATS_SERIES_H
 
+#include "statsselection.h"
+
 #include <vector>
 #include <QPointF>
 
@@ -20,10 +22,10 @@ public:
 	virtual bool hover(QPointF pos) = 0;	// Called on mouse movement. Return true if an item of this series is highlighted.
 	virtual void unhighlight() = 0;		// Unhighlight any highlighted item.
 	// Returns true if an item was under the mouse.
-	virtual bool selectItemsUnderMouse(const QPointF &pos, bool shiftPressed) = 0;
+	virtual bool selectItemsUnderMouse(const QPointF &pos, SelectionModifier modifier) = 0;
 	virtual bool supportsLassoSelection() const;
 	// Needs only be defined if supportsLassoSelection() returns true.
-	virtual void selectItemsInRect(const QRectF &rect, bool shiftPressed, const std::vector<dive *> &oldSelection);
+	virtual void selectItemsInRect(const QRectF &rect, SelectionModifier modifier, const std::vector<dive *> &oldSelection);
 	virtual void divesSelected(const QVector<dive *> &dives) = 0;
 
 protected:

stats/statsview.cpp

@@ -39,7 +39,6 @@ StatsView::StatsView(QQuickItem *parent) : QQuickItem(parent),
 	xAxis(nullptr),
 	yAxis(nullptr),
 	draggedItem(nullptr),
-	shiftSelection(false),
 	rootNode(nullptr)
 {
 	setFlag(ItemHasContents, true);
@@ -84,10 +83,12 @@ void StatsView::mousePressEvent(QMouseEvent *event)
 		}
 	}
 
-	bool shiftPressed = event->modifiers() & Qt::ShiftModifier;
+	SelectionModifier modifier;
+	modifier.shift = (event->modifiers() & Qt::ShiftModifier) != 0;
+	modifier.ctrl = (event->modifiers() & Qt::ControlModifier) != 0;
 	bool itemSelected = false;
 	for (auto &series: series)
-		itemSelected |= series->selectItemsUnderMouse(pos, shiftPressed);
+		itemSelected |= series->selectItemsUnderMouse(pos, modifier);
 
 	// The user clicked in "empty" space. If there is a series supporting lasso-select,
 	// got into lasso mode. For now, we only support a rectangular lasso.
@@ -98,8 +99,8 @@ void StatsView::mousePressEvent(QMouseEvent *event)
 			deleteChartItem(selectionRect); // Ooops. Already a selection in place.
 		dragStartMouse = pos;
 		selectionRect = createChartItem<ChartRectLineItem>(ChartZValue::Selection, selectionLassoColor, selectionLassoWidth);
-		shiftSelection = shiftPressed;
-		oldSelection = shiftPressed ? getDiveSelection() : std::vector<dive *>();
+		selectionModifier = modifier;
+		oldSelection = modifier.ctrl ? getDiveSelection() : std::vector<dive *>();
 		grabMouse();
 		setKeepMouseGrab(true); // don't allow Qt to steal the grab
 		update();
@@ -400,7 +401,7 @@ void StatsView::mouseMoveEvent(QMouseEvent *event)
 			    fabs(p2.x() - p1.x()), fabs(p2.y() - p1.y()));
 		for (auto &series: series) {
 			if (series->supportsLassoSelection())
-				series->selectItemsInRect(rect, shiftSelection, oldSelection);
+				series->selectItemsInRect(rect, selectionModifier, oldSelection);
 		}
 		update();
 	}

stats/statsview.h

@@ -4,6 +4,7 @@
 
 #include "statsstate.h"
 #include "statshelper.h"
+#include "statsselection.h"
 #include <memory>
 #include <QFont>
 #include <QImage>
@@ -145,7 +146,7 @@ private:
 	ChartItemPtr<RegressionItem> regressionItem;
 	ChartItemPtr<ChartRectLineItem> selectionRect;
 	QPointF dragStartMouse, dragStartItem;
-	bool shiftSelection;
+	SelectionModifier selectionModifier;
 	std::vector<dive *> oldSelection;
 
 	void hoverEnterEvent(QHoverEvent *event) override;