diff --git a/qglview/glwidget.cpp b/qglview/glwidget.cpp
index 364af9b..e97228e 100644
--- a/qglview/glwidget.cpp
+++ b/qglview/glwidget.cpp
@@ -12,4 +12,5 @@ GLWidget::GLWidget(QWidget *parent) : QWidget(parent)
 	lay->addWidget(container);
 	lay->setContentsMargins(0, 0, 0, 0);
 	lay->setSpacing(0);
+	setMouseTracking(true);
 }
diff --git a/qglview/openglwindow.cpp b/qglview/openglwindow.cpp
index a2813a8..6b033d4 100644
--- a/qglview/openglwindow.cpp
+++ b/qglview/openglwindow.cpp
@@ -8,8 +8,8 @@
 OpenGLWindow::OpenGLWindow(QWindow *parent)
 	: QWindow(parent)
 	, m_animating(false)
-	, m_context(0)
-	, m_device(0)
+	, m_context(nullptr)
+	, m_device(nullptr)
 {
 	setFlag(Qt::FramelessWindowHint);
 	setSurfaceType(QWindow::OpenGLSurface);
diff --git a/qglview/openglwindow.h b/qglview/openglwindow.h
index 19ae683..d9338bd 100644
--- a/qglview/openglwindow.h
+++ b/qglview/openglwindow.h
@@ -10,7 +10,7 @@ class OpenGLWindow : public QWindow, protected QOpenGLFunctions
 {
 	Q_OBJECT
 public:
-	explicit OpenGLWindow(QWindow *parent = 0);
+	explicit OpenGLWindow(QWindow *parent = nullptr);
 	~OpenGLWindow();
 
 	virtual void render(QPainter *painter);