Added horizontal scrolling by pressiong Shift + mouse wheel.

--HG--
branch : develop

ChangeLog.txt

@@ -1,4 +1,5 @@
 # Version 0.5.0
+- Added horizontal scrolling by pressiong Shift + mouse wheel.
 - [#366] Update 'Point from Distance and Angle' tool to read distance and angle between points.
 - [#395] Create Curve tool which uses point as control handle.
 - pdftops updated to version 3.04.

src/libs/vwidgets/vmaingraphicsview.cpp

@@ -44,15 +44,27 @@ const int GraphicsViewZoom::updateInterval = 40;
 
 //---------------------------------------------------------------------------------------------------------------------
 GraphicsViewZoom::GraphicsViewZoom(QGraphicsView* view)
-  : QObject(view), _view(view), _modifiers(Qt::ControlModifier), _zoom_factor_base(1.0015),
+  : QObject(view),
-    target_scene_pos(QPointF()), target_viewport_pos(QPointF()), anim(nullptr), _numScheduledScrollings(0)
+    _view(view),
+    _modifiers(Qt::ControlModifier),
+    _zoom_factor_base(1.0015),
+    target_scene_pos(QPointF()),
+    target_viewport_pos(QPointF()),
+    verticalScrollAnim(new QTimeLine(duration, this)),
+    _numScheduledVerticalScrollings(0),
+    horizontalScrollAnim(new QTimeLine(duration, this)),
+    _numScheduledHorizontalScrollings(0)
 {
   _view->viewport()->installEventFilter(this);
   _view->setMouseTracking(true);
-  anim = new QTimeLine(duration, this);
+
-  anim->setUpdateInterval(updateInterval);
+  verticalScrollAnim->setUpdateInterval(updateInterval);
-  connect(anim, &QTimeLine::valueChanged, this, &GraphicsViewZoom::scrollingTime, Qt::UniqueConnection);
+  connect(verticalScrollAnim, &QTimeLine::valueChanged, this, &GraphicsViewZoom::VerticalScrollingTime);
-  connect(anim, &QTimeLine::finished, this, &GraphicsViewZoom::animFinished, Qt::UniqueConnection);
+  connect(verticalScrollAnim, &QTimeLine::finished, this, &GraphicsViewZoom::animFinished);
+
+  horizontalScrollAnim->setUpdateInterval(updateInterval);
+  connect(horizontalScrollAnim, &QTimeLine::valueChanged, this, &GraphicsViewZoom::HorizontalScrollingTime);
+  connect(horizontalScrollAnim, &QTimeLine::finished, this, &GraphicsViewZoom::animFinished);
 }
 
 //---------------------------------------------------------------------------------------------------------------------
@@ -91,31 +103,53 @@ void GraphicsViewZoom::set_zoom_factor_base(double value)
 }
 
 //---------------------------------------------------------------------------------------------------------------------
-void GraphicsViewZoom::scrollingTime(qreal x)
+void GraphicsViewZoom::VerticalScrollingTime(qreal x)
 {
     Q_UNUSED(x);
     // Try to adapt scrolling to speed of rotating mouse wheel and scale factor
     // Value of _numScheduledScrollings is too short, so we scale the value
 
-    qreal scroll = (qAbs(_numScheduledScrollings)*(10 + 10/_view->transform().m22()))/(duration/updateInterval);
+    qreal scroll = (qAbs(_numScheduledVerticalScrollings)*(10 + 10/_view->transform().m22()))/(duration/updateInterval);
 
     if (qAbs(scroll) < 1)
     {
         scroll = 1;
     }
 
-    if (_numScheduledScrollings > 0)
+    if (_numScheduledVerticalScrollings > 0)
     {
         scroll = scroll * -1;
     }
     _view->verticalScrollBar()->setValue(qRound(_view->verticalScrollBar()->value() + scroll));
 }
 
+//---------------------------------------------------------------------------------------------------------------------
+void GraphicsViewZoom::HorizontalScrollingTime(qreal x)
+{
+    Q_UNUSED(x);
+    // Try to adapt scrolling to speed of rotating mouse wheel and scale factor
+    // Value of _numScheduledScrollings is too short, so we scale the value
+
+    qreal scroll = (qAbs(_numScheduledHorizontalScrollings)*(10 + 10/_view->transform().m11()))/
+            (duration/updateInterval);
+
+    if (qAbs(scroll) < 1)
+    {
+        scroll = 1;
+    }
+
+    if (_numScheduledHorizontalScrollings > 0)
+    {
+        scroll = scroll * -1;
+    }
+    _view->horizontalScrollBar()->setValue(qRound(_view->horizontalScrollBar()->value() + scroll));
+}
+
 //---------------------------------------------------------------------------------------------------------------------
 void GraphicsViewZoom::animFinished()
 {
-    _numScheduledScrollings = 0;
+    _numScheduledVerticalScrollings = 0;
-    anim->stop();
+    verticalScrollAnim->stop();
 
     /*
      * In moust cases cursor position on view doesn't change, but for scene after scrolling position will be different.
@@ -154,6 +188,7 @@ bool GraphicsViewZoom::eventFilter(QObject *object, QEvent *event)
     else if (event->type() == QEvent::Wheel)
     {
         QWheelEvent* wheel_event = static_cast<QWheelEvent*>(event);
+        SCASSERT(wheel_event != nullptr);
         if (QApplication::keyboardModifiers() == _modifiers)
         {
             if (wheel_event->orientation() == Qt::Vertical)
@@ -166,34 +201,14 @@ bool GraphicsViewZoom::eventFilter(QObject *object, QEvent *event)
         }
         else
         {
-            const QPoint numPixels = wheel_event->pixelDelta();
+            if (QApplication::keyboardModifiers() == Qt::ShiftModifier)
-            const QPoint numDegrees = wheel_event->angleDelta() / 8;
-            int numSteps;
-
-            if (not numPixels.isNull())
             {
-                numSteps = numPixels.y();
+                return StartHorizontalScrollings(wheel_event);
-            }
-            else if (not numDegrees.isNull())
-            {
-                numSteps = numDegrees.y() / 15;
             }
             else
             {
-                return true;//Just ignore
+                return StartVerticalScrollings(wheel_event);
             }
-
-            _numScheduledScrollings += numSteps;
-            if (_numScheduledScrollings * numSteps < 0)
-            {  // if user moved the wheel in another direction, we reset previously scheduled scalings
-                _numScheduledScrollings = numSteps;
-            }
-
-            if (anim->state() != QTimeLine::Running)
-            {
-                anim->start();
-            }
-            return true;
         }
     }
 
@@ -230,6 +245,76 @@ void GraphicsViewZoom::FictiveSceneRect(QGraphicsScene *sc, QGraphicsView *view)
     sc->setSceneRect(newRect);
 }
 
+//---------------------------------------------------------------------------------------------------------------------
+bool GraphicsViewZoom::StartVerticalScrollings(QWheelEvent *wheel_event)
+{
+    SCASSERT(wheel_event != nullptr);
+
+    const QPoint numPixels = wheel_event->pixelDelta();
+    const QPoint numDegrees = wheel_event->angleDelta() / 8;
+    int numSteps;
+
+    if (not numPixels.isNull())
+    {
+        numSteps = numPixels.y();
+    }
+    else if (not numDegrees.isNull())
+    {
+        numSteps = numDegrees.y() / 15;
+    }
+    else
+    {
+        return true;//Just ignore
+    }
+
+    _numScheduledVerticalScrollings += numSteps;
+    if (_numScheduledVerticalScrollings * numSteps < 0)
+    {  // if user moved the wheel in another direction, we reset previously scheduled scalings
+        _numScheduledVerticalScrollings = numSteps;
+    }
+
+    if (verticalScrollAnim->state() != QTimeLine::Running)
+    {
+        verticalScrollAnim->start();
+    }
+    return true;
+}
+
+//---------------------------------------------------------------------------------------------------------------------
+bool GraphicsViewZoom::StartHorizontalScrollings(QWheelEvent *wheel_event)
+{
+    SCASSERT(wheel_event != nullptr);
+
+    const QPoint numPixels = wheel_event->pixelDelta();
+    const QPoint numDegrees = wheel_event->angleDelta() / 8;
+    int numSteps;
+
+    if (not numPixels.isNull())
+    {
+        numSteps = numPixels.y();
+    }
+    else if (not numDegrees.isNull())
+    {
+        numSteps = numDegrees.y() / 15;
+    }
+    else
+    {
+        return true;//Just ignore
+    }
+
+    _numScheduledHorizontalScrollings += numSteps;
+    if (_numScheduledHorizontalScrollings * numSteps < 0)
+    {  // if user moved the wheel in another direction, we reset previously scheduled scalings
+        _numScheduledHorizontalScrollings = numSteps;
+    }
+
+    if (horizontalScrollAnim->state() != QTimeLine::Running)
+    {
+        horizontalScrollAnim->start();
+    }
+    return true;
+}
+
 //---------------------------------------------------------------------------------------------------------------------
 /**
  * @brief VMainGraphicsView constructor.

src/libs/vwidgets/vmaingraphicsview.h

@@ -71,25 +71,32 @@ public:
 signals:
     void zoomed();
 public slots:
-    void scrollingTime(qreal x);
+    void VerticalScrollingTime(qreal x);
+    void HorizontalScrollingTime(qreal x);
     void animFinished();
 protected:
     virtual bool eventFilter(QObject* object, QEvent* event) Q_DECL_OVERRIDE;
 private:
     Q_DISABLE_COPY(GraphicsViewZoom)
-    QGraphicsView*        _view;
+    QGraphicsView        *_view;
     Qt::KeyboardModifiers _modifiers;
     double                _zoom_factor_base;
     QPointF               target_scene_pos;
     QPointF               target_viewport_pos;
-    QTimeLine            *anim;
+    QTimeLine            *verticalScrollAnim;
-    /** @brief _numScheduledScalings keep number scheduled scalings. */
+    /** @brief _numScheduledVerticalScrollings keep number scheduled vertical scrollings. */
-    qint32   _numScheduledScrollings;
+    qint32                _numScheduledVerticalScrollings;
+    QTimeLine            *horizontalScrollAnim;
+    /** @brief _numScheduledHorizontalScrollings keep number scheduled horizontal scrollings. */
+    qint32                _numScheduledHorizontalScrollings;
 
     static const int duration;
     static const int updateInterval;
 
     void FictiveSceneRect(QGraphicsScene *sc, QGraphicsView *view);
+
+    bool StartVerticalScrollings(QWheelEvent* wheel_event);
+    bool StartHorizontalScrollings(QWheelEvent* wheel_event);
 };
 
 /**