Allow setting bounds for camera zoom level

Task-number: QTRD-3337
Change-Id: I503dc4402907a2fdfa74ca86698b0e98a23b3b08
Reviewed-by: Tomi Korpipää <tomi.korpipaa@digia.com>

7 files changed, 154 insertions, 60 deletions

diff --git a/examples/datavisualization/volumetric/volumetric.cpp b/examples/datavisualization/volumetric/volumetric.cpp
index 65599c31..ade74fb2 100644
--- a/examples/datavisualization/volumetric/volumetric.cpp
+++ b/examples/datavisualization/volumetric/volumetric.cpp
@@ -87,8 +87,9 @@ VolumetricModifier::VolumetricModifier(Q3DScatter *scatter)
     //! [6]
     m_graph->activeTheme()->setBackgroundEnabled(false);
 
-    // Only allow zooming at the center to avoid clipping issues
+    // Only allow zooming at the center and limit the zoom to 200% to avoid clipping issues
     static_cast<Q3DInputHandler *>(m_graph->activeInputHandler())->setZoomAtTargetEnabled(false);
+    m_graph->scene()->activeCamera()->setMaxZoomLevel(200.0f);
 
     toggleAreaAll(true);
 
@@ -204,8 +205,6 @@ VolumetricModifier::VolumetricModifier(Q3DScatter *scatter)
     m_graph->addCustomItem(warningLabel);
 #endif
 
-    QObject::connect(m_graph->scene()->activeCamera(), &Q3DCamera::zoomLevelChanged, this,
-                     &VolumetricModifier::handleZoomLevelChange);
     QObject::connect(m_graph, &QAbstract3DGraph::currentFpsChanged, this,
                      &VolumetricModifier::handleFpsChange);
     QObject::connect(&m_timer, &QTimer::timeout, this,
@@ -310,13 +309,6 @@ void VolumetricModifier::adjustSliceZ(int value)
     }
 }
 
-void VolumetricModifier::handleZoomLevelChange()
-{
-    // Zooming inside volumetric object causes ugly clipping issues, so restrict zoom level a bit
-    if (m_graph->scene()->activeCamera()->zoomLevel() > 200)
-        m_graph->scene()->activeCamera()->setZoomLevel(200);
-}
-
 void VolumetricModifier::handleFpsChange(qreal fps)
 {
     const QString fpsFormat = QStringLiteral("FPS: %1");
diff --git a/examples/datavisualization/volumetric/volumetric.h b/examples/datavisualization/volumetric/volumetric.h
index 7a4e7179..8d28b524 100644
--- a/examples/datavisualization/volumetric/volumetric.h
+++ b/examples/datavisualization/volumetric/volumetric.h
@@ -50,7 +50,6 @@ public slots:
     void adjustSliceX(int value);
     void adjustSliceY(int value);
     void adjustSliceZ(int value);
-    void handleZoomLevelChange();
     void handleFpsChange(qreal fps);
     void handleTimeout();
     void toggleLowDetail(bool enabled);
diff --git a/src/datavisualization/engine/q3dcamera.cpp b/src/datavisualization/engine/q3dcamera.cpp
index 0c2a8d82..9c3e4c08 100644
--- a/src/datavisualization/engine/q3dcamera.cpp
+++ b/src/datavisualization/engine/q3dcamera.cpp
@@ -110,8 +110,36 @@ QT_BEGIN_NAMESPACE_DATAVISUALIZATION
 /*!
  * \qmlproperty float Camera3D::zoomLevel
  *
- * This property contains the the camera zoom level in percentage. 100.0 means there is no zoom
- * in or out set in the camera.
+ * This property contains the the camera zoom level in percentage. The default value of \c{100.0}
+ * means there is no zoom in or out set in the camera.
+ * The value is limited within the bounds defined by minZoomLevel and maxZoomLevel properties.
+ *
+ * \sa minZoomLevel, maxZoomLevel
+ */
+
+/*!
+ * \qmlproperty float Camera3D::minZoomLevel
+ *
+ * This property contains the the minimum allowed camera zoom level.
+ * If the new minimum level is more than the existing maximum level, the maximum level is
+ * adjusted to the new minimum as well.
+ * If current zoomLevel is outside the new bounds, it is adjusted as well.
+ * The minZoomLevel cannot be set below \c{1.0}.
+ * Defaults to \c{10.0}.
+ *
+ * \sa zoomLevel, maxZoomLevel
+ */
+
+/*!
+ * \qmlproperty float Camera3D::maxZoomLevel
+ *
+ * This property contains the the maximum allowed camera zoom level.
+ * If the new maximum level is less than the existing minimum level, the minimum level is
+ * adjusted to the new maximum as well.
+ * If current zoomLevel is outside the new bounds, it is adjusted as well.
+ * Defaults to \c{500.0f}.
+ *
+ * \sa zoomLevel, minZoomLevel
  */
 
 /*!
@@ -191,6 +219,8 @@ void Q3DCamera::copyValuesFrom(const Q3DObject &source)
     d_ptr->m_wrapYRotation = sourceCamera.d_ptr->m_wrapYRotation;
 
     d_ptr->m_zoomLevel = sourceCamera.d_ptr->m_zoomLevel;
+    d_ptr->m_minZoomLevel = sourceCamera.d_ptr->m_minZoomLevel;
+    d_ptr->m_maxZoomLevel = sourceCamera.d_ptr->m_maxZoomLevel;
     d_ptr->m_activePreset = sourceCamera.d_ptr->m_activePreset;
 }
 
@@ -401,8 +431,11 @@ void Q3DCamera::setCameraPreset(CameraPreset preset)
 /*!
  * \property Q3DCamera::zoomLevel
  *
- * This property contains the the camera zoom level in percentage. \c 100.0f means there is no zoom
- * in or out set in the camera.
+ * This property contains the the camera zoom level in percentage. The default value of \c{100.0f}
+ * means there is no zoom in or out set in the camera.
+ * The value is limited within the bounds defined by minZoomLevel and maxZoomLevel properties.
+ *
+ * \sa minZoomLevel, maxZoomLevel
  */
 float Q3DCamera::zoomLevel() const
 {
@@ -411,10 +444,73 @@ float Q3DCamera::zoomLevel() const
 
 void Q3DCamera::setZoomLevel(float zoomLevel)
 {
-    if (d_ptr->m_zoomLevel != zoomLevel) {
-        d_ptr->m_zoomLevel = zoomLevel;
+    float newZoomLevel = qBound(d_ptr->m_minZoomLevel, zoomLevel, d_ptr->m_maxZoomLevel);
+
+    if (d_ptr->m_zoomLevel != newZoomLevel) {
+        d_ptr->m_zoomLevel = newZoomLevel;
+        setDirty(true);
+        emit zoomLevelChanged(newZoomLevel);
+    }
+}
+
+/*!
+ * \property Q3DCamera::minZoomLevel
+ *
+ * This property contains the the minimum allowed camera zoom level.
+ * If the new minimum level is more than the existing maximum level, the maximum level is
+ * adjusted to the new minimum as well.
+ * If current zoomLevel is outside the new bounds, it is adjusted as well.
+ * The minZoomLevel cannot be set below \c{1.0f}.
+ * Defaults to \c{10.0f}.
+ *
+ * \sa zoomLevel, maxZoomLevel
+ */
+float Q3DCamera::minZoomLevel() const
+{
+    return d_ptr->m_minZoomLevel;
+}
+
+void Q3DCamera::setMinZoomLevel(float zoomLevel)
+{
+    // Don't allow minimum to be below one, as that can cause zoom to break.
+    float newMinLevel = qMax(zoomLevel, 1.0f);
+    if (d_ptr->m_minZoomLevel != newMinLevel) {
+        d_ptr->m_minZoomLevel = newMinLevel;
+        if (d_ptr->m_maxZoomLevel < newMinLevel)
+            setMaxZoomLevel(newMinLevel);
+        setZoomLevel(d_ptr->m_zoomLevel);
+        setDirty(true);
+        emit minZoomLevelChanged(newMinLevel);
+    }
+}
+
+/*!
+ * \property Q3DCamera::maxZoomLevel
+ *
+ * This property contains the the maximum allowed camera zoom level.
+ * If the new maximum level is less than the existing minimum level, the minimum level is
+ * adjusted to the new maximum as well.
+ * If current zoomLevel is outside the new bounds, it is adjusted as well.
+ * Defaults to \c{500.0f}.
+ *
+ * \sa zoomLevel, minZoomLevel
+ */
+float Q3DCamera::maxZoomLevel() const
+{
+    return d_ptr->m_maxZoomLevel;
+}
+
+void Q3DCamera::setMaxZoomLevel(float zoomLevel)
+{
+    // Don't allow maximum to be below one, as that can cause zoom to break.
+    float newMaxLevel = qMax(zoomLevel, 1.0f);
+    if (d_ptr->m_maxZoomLevel != newMaxLevel) {
+        d_ptr->m_maxZoomLevel = newMaxLevel;
+        if (d_ptr->m_minZoomLevel > newMaxLevel)
+            setMinZoomLevel(newMaxLevel);
+        setZoomLevel(d_ptr->m_zoomLevel);
         setDirty(true);
-        emit zoomLevelChanged(zoomLevel);
+        emit maxZoomLevelChanged(newMaxLevel);
     }
 }
 
@@ -461,12 +557,12 @@ void Q3DCamera::setWrapYRotation(bool isEnabled)
 /*!
  * Utility function that sets the camera rotations and distance.\a horizontal and \a vertical
  * define the camera rotations to be used.
- * Optional \a zoom parameter can be given to set the zoom percentage of the camera in range of
- * \c{10.0f - 500.0f}.
+ * Optional \a zoom parameter can be given to set the zoom percentage of the camera within
+ * the bounds defined by minZoomLevel and maxZoomLevel properties.
  */
 void Q3DCamera::setCameraPosition(float horizontal, float vertical, float zoom)
 {
-    setZoomLevel(qBound(10.0f, zoom, 500.0f));
+    setZoomLevel(zoom);
     setXRotation(horizontal);
     setYRotation(vertical);
 }
@@ -524,6 +620,8 @@ Q3DCameraPrivate::Q3DCameraPrivate(Q3DCamera *q) :
     m_maxXRotation(180.0f),
     m_maxYRotation(90.0f),
     m_zoomLevel(100.0f),
+    m_minZoomLevel(10.0f),
+    m_maxZoomLevel(500.0f),
     m_wrapXRotation(true),
     m_wrapYRotation(false),
     m_activePreset(Q3DCamera::CameraPresetNone)
diff --git a/src/datavisualization/engine/q3dcamera.h b/src/datavisualization/engine/q3dcamera.h
index a7da9031..5b539ccf 100644
--- a/src/datavisualization/engine/q3dcamera.h
+++ b/src/datavisualization/engine/q3dcamera.h
@@ -36,6 +36,8 @@ class QT_DATAVISUALIZATION_EXPORT Q3DCamera : public Q3DObject
     Q_PROPERTY(bool wrapXRotation READ wrapXRotation WRITE setWrapXRotation NOTIFY wrapXRotationChanged)
     Q_PROPERTY(bool wrapYRotation READ wrapYRotation WRITE setWrapYRotation NOTIFY wrapYRotationChanged)
     Q_PROPERTY(QVector3D target READ target WRITE setTarget NOTIFY targetChanged REVISION 1)
+    Q_PROPERTY(float minZoomLevel READ minZoomLevel WRITE setMinZoomLevel NOTIFY minZoomLevelChanged REVISION 1)
+    Q_PROPERTY(float maxZoomLevel READ maxZoomLevel WRITE setMaxZoomLevel NOTIFY maxZoomLevelChanged REVISION 1)
 
 public:
     enum CameraPreset {
@@ -87,6 +89,10 @@ public:
 
     float zoomLevel() const;
     void setZoomLevel(float zoomLevel);
+    float minZoomLevel() const;
+    void setMinZoomLevel(float zoomLevel);
+    float maxZoomLevel() const;
+    void setMaxZoomLevel(float zoomLevel);
 
     void setCameraPosition(float horizontal, float vertical, float zoom = 100.0f);
 
@@ -101,6 +107,8 @@ signals:
     void wrapXRotationChanged(bool isEnabled);
     void wrapYRotationChanged(bool isEnabled);
     Q_REVISION(1) void targetChanged(const QVector3D &target);
+    Q_REVISION(1) void minZoomLevelChanged(float zoomLevel);
+    Q_REVISION(1) void maxZoomLevelChanged(float zoomLevel);
 
 private:
     QScopedPointer<Q3DCameraPrivate> d_ptr;
diff --git a/src/datavisualization/engine/q3dcamera_p.h b/src/datavisualization/engine/q3dcamera_p.h
index 6e9fd190..b7826a5b 100644
--- a/src/datavisualization/engine/q3dcamera_p.h
+++ b/src/datavisualization/engine/q3dcamera_p.h
@@ -90,13 +90,15 @@ public:
     QMatrix4x4 m_viewMatrix;
     bool m_isViewMatrixUpdateActive;
 
-    GLfloat m_xRotation;
-    GLfloat m_yRotation;
-    GLfloat m_minXRotation;
-    GLfloat m_minYRotation;
-    GLfloat m_maxXRotation;
-    GLfloat m_maxYRotation;
-    GLfloat m_zoomLevel;
+    float m_xRotation;
+    float m_yRotation;
+    float m_minXRotation;
+    float m_minYRotation;
+    float m_maxXRotation;
+    float m_maxYRotation;
+    float m_zoomLevel;
+    float m_minZoomLevel;
+    float m_maxZoomLevel;
     bool m_wrapXRotation;
     bool m_wrapYRotation;
     Q3DCamera::CameraPreset m_activePreset;
diff --git a/src/datavisualization/input/q3dinputhandler.cpp b/src/datavisualization/input/q3dinputhandler.cpp
index 0bed3cb9..43cee84e 100644
--- a/src/datavisualization/input/q3dinputhandler.cpp
+++ b/src/datavisualization/input/q3dinputhandler.cpp
@@ -22,18 +22,16 @@
 
 QT_BEGIN_NAMESPACE_DATAVISUALIZATION
 
-const int minZoomLevel           = 10;
-const int halfSizeZoomLevel      = 50;
-const int oneToOneZoomLevel      = 100;
-const int maxZoomLevel           = 500;
-const int driftTowardCenterLevel = 175;
-const float wheelZoomDrift       = 0.1f;
+static const int halfSizeZoomLevel      = 50;
+static const int oneToOneZoomLevel      = 100;
+static const int driftTowardCenterLevel = 175;
+static const float wheelZoomDrift       = 0.1f;
 
-const int nearZoomRangeDivider = 12;
-const int midZoomRangeDivider  = 60;
-const int farZoomRangeDivider  = 120;
+static const int nearZoomRangeDivider = 12;
+static const int midZoomRangeDivider  = 60;
+static const int farZoomRangeDivider  = 120;
 
-const float rotationSpeed      = 100.0f;
+static const float rotationSpeed      = 100.0f;
 
 /*!
  * \class Q3DInputHandler
@@ -58,7 +56,7 @@ const float rotationSpeed      = 100.0f;
  *              \l {QAbstract3DGraph::selectionMode}{selection mode}.
  *      \row
  *          \li Mouse wheel
- *          \li Zoom in/out within default range (10...500%).
+ *          \li Zoom in/out within the allowable zoom range set for Q3DCamera.
  *      \row
  *          \li Left click on the primary view when the secondary view is visible
  *          \li Closes the secondary view.
@@ -239,17 +237,17 @@ void Q3DInputHandler::wheelEvent(QWheelEvent *event)
             return;
 
         // Adjust zoom level based on what zoom range we're in.
-        int zoomLevel = scene()->activeCamera()->zoomLevel();
+        Q3DCamera *camera = scene()->activeCamera();
+        int zoomLevel = int(camera->zoomLevel());
+        const int minZoomLevel = int(camera->minZoomLevel());
+        const int maxZoomLevel = int(camera->maxZoomLevel());
         if (zoomLevel > oneToOneZoomLevel)
             zoomLevel += event->angleDelta().y() / nearZoomRangeDivider;
         else if (zoomLevel > halfSizeZoomLevel)
             zoomLevel += event->angleDelta().y() / midZoomRangeDivider;
         else
             zoomLevel += event->angleDelta().y() / farZoomRangeDivider;
-        if (zoomLevel > maxZoomLevel)
-            zoomLevel = maxZoomLevel;
-        else if (zoomLevel < minZoomLevel)
-            zoomLevel = minZoomLevel;
+        zoomLevel = qBound(minZoomLevel, zoomLevel, maxZoomLevel);
 
         if (isZoomAtTargetEnabled()) {
             scene()->setGraphPositionQuery(event->pos());
@@ -259,7 +257,7 @@ void Q3DInputHandler::wheelEvent(QWheelEvent *event)
             d_ptr->m_requestedZoomLevel = zoomLevel;
             d_ptr->m_driftMultiplier = wheelZoomDrift;
         } else {
-            scene()->activeCamera()->setZoomLevel(zoomLevel);
+            camera->setZoomLevel(zoomLevel);
         }
     }
 }
diff --git a/src/datavisualization/input/qtouch3dinputhandler.cpp b/src/datavisualization/input/qtouch3dinputhandler.cpp
index b811548b..20eebb58 100644
--- a/src/datavisualization/input/qtouch3dinputhandler.cpp
+++ b/src/datavisualization/input/qtouch3dinputhandler.cpp
@@ -22,18 +22,16 @@
 
 QT_BEGIN_NAMESPACE_DATAVISUALIZATION
 
-const float maxTapAndHoldJitter = 20.0f;
-const int maxPinchJitter = 10;
+static const float maxTapAndHoldJitter = 20.0f;
+static const int maxPinchJitter = 10;
 #if defined (Q_OS_ANDROID) || defined(Q_OS_IOS)
-const int maxSelectionJitter = 10;
+static const int maxSelectionJitter = 10;
 #else
-const int maxSelectionJitter = 5;
+static const int maxSelectionJitter = 5;
 #endif
-const int tapAndHoldTime = 250;
-const float rotationSpeed = 200.0f;
-const int minZoomLevel = 10;
-const int maxZoomLevel = 500;
-const float touchZoomDrift = 0.02f;
+static const int tapAndHoldTime = 250;
+static const float rotationSpeed = 200.0f;
+static const float touchZoomDrift = 0.02f;
 
 /*!
  * \class QTouch3DInputHandler
@@ -61,7 +59,7 @@ const float touchZoomDrift = 0.02f;
  *          \li Same as tap.
  *      \row
  *          \li Pinch
- *          \li Zoom in/out within default range (10...500%).
+ *          \li Zoom in/out within the allowable zoom range set for Q3DCamera.
  *      \row
  *          \li Tap on the primary view when the secondary view is visible
  *          \li Closes the secondary view.
@@ -193,16 +191,15 @@ void QTouch3DInputHandlerPrivate::handlePinchZoom(float distance, const QPoint &
             return;
         m_inputState = QAbstract3DInputHandlerPrivate::InputStatePinching;
         Q3DCamera *camera = q_ptr->scene()->activeCamera();
-        int zoomLevel = camera->zoomLevel();
+        int zoomLevel = int(camera->zoomLevel());
+        const int minZoomLevel = int(camera->minZoomLevel());
+        const int maxZoomLevel = int(camera->maxZoomLevel());
         float zoomRate = qSqrt(qSqrt(zoomLevel));
         if (newDistance > prevDist)
             zoomLevel += zoomRate;
         else
             zoomLevel -= zoomRate;
-        if (zoomLevel > maxZoomLevel)
-            zoomLevel = maxZoomLevel;
-        else if (zoomLevel < minZoomLevel)
-            zoomLevel = minZoomLevel;
+        zoomLevel = qBound(minZoomLevel, zoomLevel, maxZoomLevel);
 
         if (q_ptr->isZoomAtTargetEnabled()) {
             q_ptr->scene()->setGraphPositionQuery(pos);