Implement zooming with Control key and mousewheel

mainwidget.cpp

@@ -25,6 +25,7 @@
 #include <QGraphicsItemGroup>
 #include <QGraphicsProxyWidget>
 #include <QGraphicsScene>
+#include <QGraphicsSceneEvent>
 #include <QKeyEvent>
 #include <QMenu>
 #include <QMimeData>
@@ -560,6 +561,8 @@ LevelOneScene::LevelOneScene(QWidget *levelOneWidget, QObject *parent) : QGraphi
 				m_sidePanelGridItemGroup[c]->addToGroup(gridPiece);
 			}
 	}
+
+	installEventFilter(this);
 }
 
 void LevelOneScene::setBorderDimensions(int sceneWidth, int sceneHeight, int widgetWidth, int leftSidePanelColumns, int rightSidePanelColumns)
@@ -637,6 +640,22 @@ void LevelOneScene::toggleGrid(bool gridOn)
 			m_sidePanelGridItemGroup[i]->setVisible(gridOn);
 }
 
+bool LevelOneScene::eventFilter(QObject *object, QEvent *event)
+{
+	Q_UNUSED(object);
+
+	if (event->type() == QEvent::GraphicsSceneWheel && static_cast<QGraphicsSceneWheelEvent *>(event)->modifiers() == Qt::ControlModifier) {
+		if (static_cast<QGraphicsSceneWheelEvent *>(event)->delta() > 0)
+			emit mouseZoomIn();
+		else if (static_cast<QGraphicsSceneWheelEvent *>(event)->delta() < 0)
+			emit mouseZoomOut();
+
+		event->accept();
+		return true;
+	}
+	return false;
+}
+
 void LevelOneScene::setFullScreenColour(const QColor &newColor)
 {
 	m_fullScreenTopRectItem->setBrush(QBrush(newColor));

mainwidget.h

@@ -121,7 +121,13 @@ public slots:
 	void setFullScreenColour(const QColor &);
 	void setFullRowColour(int, const QColor &);
 
+signals:
+	void mouseZoomIn();
+	void mouseZoomOut();
+
 private:
+	bool eventFilter(QObject *, QEvent *);
+
 	QGraphicsRectItem *m_fullScreenTopRectItem, *m_fullScreenBottomRectItem;
 	QGraphicsRectItem *m_fullRowLeftRectItem[25], *m_fullRowRightRectItem[25];
 	QGraphicsProxyWidget *m_levelOneProxyWidget;

mainwindow.cpp

@@ -181,6 +181,9 @@ void MainWindow::init()
 	connect(m_textWidget->pageRender(), &TeletextPageRender::fullRowColourChanged, m_textScene, &LevelOneScene::setFullRowColour);
 	connect(m_textWidget, &TeletextWidget::insertKeyPressed, this, &MainWindow::toggleInsertMode);
 
+	connect(m_textScene, &LevelOneScene::mouseZoomIn, this, &MainWindow::zoomIn);
+	connect(m_textScene, &LevelOneScene::mouseZoomOut, this, &MainWindow::zoomOut);
+
 	QShortcut *blockShortCut = new QShortcut(QKeySequence(Qt::Key_Escape, Qt::Key_J), m_textView);
 	connect(blockShortCut, &QShortcut::activated, [=]() { m_textWidget->setCharacter(0x7f); });