Shadow points change opacity to show highlighting

src/Graphics/GraphicsPoint.cpp

@@ -149,6 +149,8 @@ void GraphicsPoint::createPointEllipse (unsigned int radius)
 
   m_shadowZeroWidthEllipse->setPen (QPen (QBrush (m_color), ZERO_WIDTH));
   m_shadowZeroWidthEllipse->setEnabled (true);
+
+  m_graphicsItemEllipse->setShadow (m_shadowZeroWidthEllipse);
 }
 
 void GraphicsPoint::createPointPolygon (const QPolygonF &polygon)
@@ -183,6 +185,8 @@ void GraphicsPoint::createPointPolygon (const QPolygonF &polygon)
 
   m_shadowZeroWidthPolygon->setPen (QPen (QBrush (m_color), ZERO_WIDTH));
   m_shadowZeroWidthPolygon->setEnabled (true);
+
+  m_graphicsItemPolygon->setShadow (m_shadowZeroWidthPolygon);
 }
 
 QVariant GraphicsPoint::data (int key) const

src/Graphics/GraphicsPointEllipse.cpp

@@ -15,7 +15,8 @@
 GraphicsPointEllipse::GraphicsPointEllipse(GraphicsPoint &graphicsPoint,
                                            const QRect &rect) :
   QGraphicsEllipseItem (rect),
-  m_graphicsPoint (graphicsPoint)
+  m_graphicsPoint (graphicsPoint),
+  m_shadow (0)
 {
   LOG4CPP_INFO_S ((*mainCat)) << "GraphicsPointEllipse::GraphicsPointEllipse";
 }
@@ -39,7 +40,7 @@ QVariant GraphicsPointEllipse::itemChange(GraphicsItemChange change,
 void GraphicsPointEllipse::hoverEnterEvent(QGraphicsSceneHoverEvent *event)
 {
   // Highlighted
-  setOpacity(m_graphicsPoint.highlightOpacity ());
+  setOpacityForSubtree (m_graphicsPoint.highlightOpacity());
 
   emit signalPointHoverEnter (data (DATA_KEY_IDENTIFIER).toString ());
 
@@ -49,16 +50,33 @@ void GraphicsPointEllipse::hoverEnterEvent(QGraphicsSceneHoverEvent *event)
 void GraphicsPointEllipse::hoverLeaveEvent(QGraphicsSceneHoverEvent *event)
 {
   // Unhighlighted
-  setOpacity(MAX_OPACITY);
+  setOpacityForSubtree (MAX_OPACITY);
 
   emit signalPointHoverLeave (data (DATA_KEY_IDENTIFIER).toString ());
 
   QGraphicsEllipseItem::hoverLeaveEvent (event);
 }
 
+void GraphicsPointEllipse::setOpacityForSubtree (double opacity)
+{
+  // Set this item
+  setOpacity (opacity);
+
+  if (m_shadow != 0) {
+
+    // Set the child item. Opacity < MAX_OPACITY is too dark so child is set to totally transparent
+    m_shadow->setOpacity (opacity < MAX_OPACITY ? 0.0 : opacity);
+  }
+}
+
 void GraphicsPointEllipse::setRadius(int radius)
 {
   // Resize assuming symmetry about the origin, and an aspect ratio of 1:1 (so x and y scales are the same)
   double scale = (2 * radius) / boundingRect().width();
   setScale (scale);
 }
+
+void GraphicsPointEllipse::setShadow (GraphicsPointEllipse *shadow)
+{
+  m_shadow = shadow;
+}

src/Graphics/GraphicsPointEllipse.h

@@ -35,6 +35,9 @@ class GraphicsPointEllipse : public QObject, public QGraphicsEllipseItem
   /// Update the radius
   void setRadius(int radius);
 
+  /// Bind this graphics item to its shadow
+  void setShadow (GraphicsPointEllipse *shadow);
+
 signals:
 
   /// Signal for geometry window to highlight the current point upon hover enter
@@ -46,8 +49,12 @@ class GraphicsPointEllipse : public QObject, public QGraphicsEllipseItem
 private:
   GraphicsPointEllipse();
 
+  void setOpacityForSubtree (double opacity);
+
   // Reference to the GraphicsPoint that this class belongs to
   GraphicsPoint &m_graphicsPoint;
+
+  GraphicsPointEllipse *m_shadow;
 };
 
 #endif // GRAPHICS_POINT_ELLIPSE_H

src/Graphics/GraphicsPointPolygon.cpp

@@ -14,7 +14,8 @@
 GraphicsPointPolygon::GraphicsPointPolygon(GraphicsPoint &graphicsPoint,
                                            const QPolygonF &polygon) :
   QGraphicsPolygonItem (polygon),
-  m_graphicsPoint (graphicsPoint)
+  m_graphicsPoint (graphicsPoint),
+  m_shadow (0)
 {
   LOG4CPP_INFO_S ((*mainCat)) << "GraphicsPointPolygon::GraphicsPointPolygon";
 }
@@ -38,7 +39,7 @@ QVariant GraphicsPointPolygon::itemChange(GraphicsItemChange change,
 void GraphicsPointPolygon::hoverEnterEvent(QGraphicsSceneHoverEvent *event)
 {
   // Highlighted
-  setOpacity(m_graphicsPoint.highlightOpacity ());
+  setOpacityForSubtree (m_graphicsPoint.highlightOpacity ());
 
   emit signalPointHoverEnter (data (DATA_KEY_IDENTIFIER).toString ());
 
@@ -48,16 +49,33 @@ void GraphicsPointPolygon::hoverEnterEvent(QGraphicsSceneHoverEvent *event)
 void GraphicsPointPolygon::hoverLeaveEvent(QGraphicsSceneHoverEvent *event)
 {
   // Unhighlighted
-  setOpacity(MAX_OPACITY);
+  setOpacityForSubtree (MAX_OPACITY);
 
   emit signalPointHoverLeave (data (DATA_KEY_IDENTIFIER).toString ());
 
   QGraphicsPolygonItem::hoverLeaveEvent (event);
 }
 
+void GraphicsPointPolygon::setOpacityForSubtree (double opacity)
+{
+  // Set this item
+  setOpacity (opacity);
+
+  if (m_shadow != 0) {
+
+    // Set the child item. Opacity < MAX_OPACITY is too dark so child is set to totally transparent
+    m_shadow->setOpacity (opacity < MAX_OPACITY ? 0.0 : opacity);
+  }
+}
+
 void GraphicsPointPolygon::setRadius(int radius)
 {
   // Resize assuming symmetry about the origin, and an aspect ratio of 1:1 (so x and y scales are the same)
   double scale = (2 * radius) / boundingRect().width();
   setScale (scale);
 }
+
+void GraphicsPointPolygon::setShadow (GraphicsPointPolygon *shadow)
+{
+  m_shadow = shadow;
+}

src/Graphics/GraphicsPointPolygon.h

@@ -35,6 +35,9 @@ class GraphicsPointPolygon : public QObject, public QGraphicsPolygonItem
   /// Update the radius
   void setRadius(int radius);
 
+  /// Bind this graphics item to its shadow
+  void setShadow (GraphicsPointPolygon *shadow);
+
 signals:
 
   /// Signal for geometry window to highlight the current point upon hover enter
@@ -46,8 +49,12 @@ class GraphicsPointPolygon : public QObject, public QGraphicsPolygonItem
 private:
   GraphicsPointPolygon();
 
+  void setOpacityForSubtree (double opacity);
+
   // Reference to the GraphicsPoint that this class belongs to
   GraphicsPoint &m_graphicsPoint;
+
+  GraphicsPointPolygon *m_shadow;
 };
 
 #endif // GRAPHICS_POINT_POLYGON_H