3 files changed, 54 insertions, 8 deletions
diff --git a/src/datavisualization/data/customrenderitem_p.h b/src/datavisualization/data/customrenderitem_p.h
index 8ea8e894..84fc898a 100644
--- a/src/datavisualization/data/customrenderitem_p.h
+++ b/src/datavisualization/data/customrenderitem_p.h
@@ -55,6 +55,8 @@ public:
     inline QVector3D origScaling() const { return m_origScaling; }
     inline void setPosition(const QVector3D &position) { m_position = position; }
     inline QVector3D position() const { return m_position; }
+    inline void setOrigPosition(const QVector3D &position) { m_origPosition = position; }
+    inline QVector3D origPosition() const { return m_origPosition; }
     inline void setPositionAbsolute(bool absolute) { m_positionAbsolute = absolute; }
     inline bool isPositionAbsolute() const { return m_positionAbsolute; }
     inline void setScalingAbsolute(bool absolute) { m_scalingAbsolute = absolute; }
@@ -104,6 +106,25 @@ public:
     inline bool preserveOpacity() const { return m_preserveOpacity; }
     inline void setUseHighDefShader(bool enable) { m_useHighDefShader = enable; }
     inline bool useHighDefShader() const {return m_useHighDefShader; }
+    inline void setMinBounds(const QVector3D &bounds) {
+        m_minBounds = bounds;
+        m_minBoundsNormal = m_minBounds;
+        m_minBoundsNormal.setY(-m_minBoundsNormal.y());
+        m_minBoundsNormal.setZ(-m_minBoundsNormal.z());
+        m_minBoundsNormal = 0.5f * (m_minBoundsNormal + oneVector);
+
+    }
+    inline QVector3D minBounds() const { return m_minBounds; }
+    inline void setMaxBounds(const QVector3D &bounds) {
+        m_maxBounds = bounds;
+        m_maxBoundsNormal = m_maxBounds;
+        m_maxBoundsNormal.setY(-m_maxBoundsNormal.y());
+        m_maxBoundsNormal.setZ(-m_maxBoundsNormal.z());
+        m_maxBoundsNormal = 0.5f * (m_maxBoundsNormal + oneVector);
+    }
+    inline QVector3D maxBounds() const { return m_maxBounds; }
+    inline QVector3D minBoundsNormal() const { return m_minBoundsNormal; }
+    inline QVector3D maxBoundsNormal() const { return m_maxBoundsNormal; }
 
 private:
     Q_DISABLE_COPY(CustomRenderItem)
@@ -112,6 +133,7 @@ private:
     QVector3D m_scaling;
     QVector3D m_origScaling;
     QVector3D m_position;
+    QVector3D m_origPosition;
     bool m_positionAbsolute;
     bool m_scalingAbsolute;
     ObjectHelper *m_object; // shared reference
@@ -138,6 +160,10 @@ private:
     float m_alphaMultiplier;
     bool m_preserveOpacity;
     bool m_useHighDefShader;
+    QVector3D m_minBounds;
+    QVector3D m_maxBounds;
+    QVector3D m_minBoundsNormal;
+    QVector3D m_maxBoundsNormal;
 };
 typedef QHash<QCustom3DItem *, CustomRenderItem *> CustomRenderItemArray;
 
diff --git a/src/datavisualization/data/qcustom3ditem.cpp b/src/datavisualization/data/qcustom3ditem.cpp
index 64cb4531..4e82d47a 100644
--- a/src/datavisualization/data/qcustom3ditem.cpp
+++ b/src/datavisualization/data/qcustom3ditem.cpp
@@ -67,10 +67,10 @@ QT_BEGIN_NAMESPACE_DATAVISUALIZATION
  * within axis ranges.
  *
  * \note Items positioned outside any axis range are not rendered if positionAbsolute is \c{false},
- * unless the item is a Custom3DVolume that would be partially visible. In that case, the visible
- * portion of the volume will be rendered.
+ * unless the item is a Custom3DVolume that would be partially visible and scalingAbsolute is also
+ * \c{false}. In that case, the visible portion of the volume will be rendered.
  *
- * \sa positionAbsolute
+ * \sa positionAbsolute, scalingAbsolute
  */
 
 /*! \qmlproperty bool Custom3DItem::positionAbsolute
@@ -206,8 +206,8 @@ QString QCustom3DItem::meshFile() const
  * within axis ranges.
  *
  * \note Items positioned outside any axis range are not rendered if positionAbsolute is \c{false},
- * unless the item is a QCustom3DVolume that would be partially visible. In that case, the visible
- * portion of the volume will be rendered.
+ * unless the item is a QCustom3DVolume that would be partially visible and scalingAbsolute is also
+ * \c{false}. In that case, the visible portion of the volume will be rendered.
  *
  * \sa positionAbsolute
  */
diff --git a/src/datavisualization/data/qcustom3dvolume.cpp b/src/datavisualization/data/qcustom3dvolume.cpp
index d0e0c139..78c91802 100644
--- a/src/datavisualization/data/qcustom3dvolume.cpp
+++ b/src/datavisualization/data/qcustom3dvolume.cpp
@@ -31,9 +31,19 @@ QT_BEGIN_NAMESPACE_DATAVISUALIZATION
  * object is a box with a 3D texture. Three slice planes are supported for the volume, one along
  * each main axis of the volume.
  *
+ * Rendering volume objects is very performance intensive, especially when the volume is largely
+ * transparent, as the contents of the volume are ray-traced. The performance scales nearly linearly
+ * with the amount of pixels that the volume occupies on the screen, so showing the volume in a
+ * smaller view or limiting the zoom level of the graph are easy ways to improve performance.
+ * Similarly, the volume texture dimensions have a large impact on performance.
+ * If the frame rate is more important than pixel-perfect rendering of the volume contents, consider
+ * turning the high definition shader off by setting useHighDefShader property to \c{false}.
+ *
  * \note Volumetric objects are only supported with orthographic projection.
  *
- * \sa QAbstract3DGraph::addCustomItem(), QAbstract3DGraph::orthoProjection
+ * \note Volumetric objects utilize 3D textures, which are not supported in OpenGL ES2 environments.
+ *
+ * \sa QAbstract3DGraph::addCustomItem(), QAbstract3DGraph::orthoProjection, useHighDefShader
  */
 
 /*!
@@ -48,13 +58,23 @@ QT_BEGIN_NAMESPACE_DATAVISUALIZATION
  * object is a box with a 3D texture. Three slice planes are supported for the volume, one along
  * each main axis of the volume.
  *
+ * Rendering volume objects is very performance intensive, especially when the volume is largely
+ * transparent, as the contents of the volume are ray-traced. The performance scales nearly linearly
+ * with the amount of pixels that the volume occupies on the screen, so showing the volume in a
+ * smaller view or limiting the zoom level of the graph are easy ways to improve performance.
+ * Similarly, the volume texture dimensions have a large impact on performance.
+ * If the frame rate is more important than pixel-perfect rendering of the volume contents, consider
+ * turning the high definition shader off by setting useHighDefShader property to \c{false}.
+ *
  * \note: Filling in the volume data would not typically be efficient or practical from pure QML,
  * so properties directly related to that are not fully supported from QML.
- * Make a hybrid QML/C++ application if you want to use volume objects with QML ui.
+ * Make a hybrid QML/C++ application if you want to use volume objects with a QML UI.
  *
  * \note Volumetric objects are only supported with orthographic projection.
  *
- * \sa AbstractGraph3D::orthoProjection
+ * \note Volumetric objects utilize 3D textures, which are not supported in OpenGL ES2 environments.
+ *
+ * \sa AbstractGraph3D::orthoProjection, useHighDefShader
  */
 
 /*! \qmlproperty int Custom3DVolume::textureWidth