[composer] Fix ctrl modifier not applying to wheel events when in move item

content mode, add missing undo merge command for item zoom (refs #7974)

Author: nyalldawson

python/core/composer/qgscomposeritem.sip

@@ -133,6 +133,16 @@ class QgsComposerItem : QgsComposerObject, QGraphicsRectItem
       LowerRight
     };
 
+    /** Modes for zooming item content
+     */
+    enum ZoomMode
+    {
+      Zoom = 0, /*< Zoom to center of content */
+      ZoomRecenter, /*< Zoom and recenter content to point */
+      ZoomToPoint, /*< Zoom while maintaining relative position of point */
+      NoZoom /*< No zoom */
+    };
+
     /**Constructor
      @param composition parent composition
      @param manageZValue true if the z-Value of this object should be managed by mComposition*/
@@ -183,10 +193,20 @@ class QgsComposerItem : QgsComposerObject, QGraphicsRectItem
     virtual void moveContent( double dx, double dy );
 
     /**Zoom content of item. Does nothing per default (but implemented in composer map)
-      @param delta value from wheel event that describes magnitude and direction (positive /negative number)
-      @param x x-position of mouse cursor (in item coordinates)
-      @param y y-position of mouse cursor (in item coordinates)*/
-    virtual void zoomContent( int delta, double x, double y );
+     * @param delta value from wheel event that describes direction (positive /negative number)
+     * @param x x-position of mouse cursor (in item coordinates)
+     * @param y y-position of mouse cursor (in item coordinates)
+     * @deprecated use zoomContent( double, QPointF, ZoomMode ) instead
+    */
+    virtual void zoomContent( int delta, double x, double y ) /Deprecated/;
+
+    /**Zoom content of item. Does nothing per default (but implemented in composer map)
+     * @param factor zoom factor, where > 1 results in a zoom in and < 1 results in a zoom out
+     * @param point item point for zoom center
+     * @param mode zoom mode
+     * @note added in QGIS 2.5
+    */
+    virtual void zoomContent( const double factor, const QPointF point, const ZoomMode mode = QgsComposerItem::Zoom );
 
     /**Gets the page the item is currently on.
      * @returns page number for item

python/core/composer/qgscomposermap.sip

@@ -130,10 +130,20 @@ class QgsComposerMap : QgsComposerItem
     void moveContent( double dx, double dy );
 
     /**Zoom content of map
-     @param delta value from wheel event that describes magnitude and direction (positive /negative number)
-    @param x x-coordinate of mouse position in item coordinates
-    @param y y-coordinate of mouse position in item coordinates*/
-    void zoomContent( int delta, double x, double y );
+     * @param delta value from wheel event that describes direction (positive /negative number)
+     * @param x x-position of mouse cursor (in item coordinates)
+     * @param y y-position of mouse cursor (in item coordinates)
+     * @deprecated use zoomContent( double, QPointF, ZoomMode ) instead
+    */
+    void zoomContent( int delta, double x, double y ) /Deprecated/;
+
+    /**Zoom content of item. Does nothing per default (but implemented in composer map)
+     * @param factor zoom factor, where > 1 results in a zoom in and < 1 results in a zoom out
+     * @param point item point for zoom center
+     * @param mode zoom mode
+     * @note added in QGIS 2.5
+    */
+    virtual void zoomContent( const double factor, const QPointF point, const ZoomMode mode = QgsComposerItem::Zoom );
 
     /**Sets new scene rectangle bounds and recalculates hight and extent*/
     void setSceneRect( const QRectF& rectangle );

src/core/composer/qgscomposeritem.h

@@ -89,6 +89,18 @@ class CORE_EXPORT QgsComposerItem: public QgsComposerObject, public QGraphicsRec
       LowerRight
     };
 
+    //note - must sync with QgsMapCanvas::WheelAction.
+    //TODO - QGIS 3.0 move QgsMapCanvas::WheelAction from GUI->CORE and remove this enum
+    /** Modes for zooming item content
+     */
+    enum ZoomMode
+    {
+      Zoom = 0, /*< Zoom to center of content */
+      ZoomRecenter, /*< Zoom and recenter content to point */
+      ZoomToPoint, /*< Zoom while maintaining relative position of point */
+      NoZoom /*< No zoom */
+    };
+
     /**Constructor
      @param composition parent composition
      @param manageZValue true if the z-Value of this object should be managed by mComposition*/
@@ -139,10 +151,20 @@ class CORE_EXPORT QgsComposerItem: public QgsComposerObject, public QGraphicsRec
     virtual void moveContent( double dx, double dy ) { Q_UNUSED( dx ); Q_UNUSED( dy ); }
 
     /**Zoom content of item. Does nothing per default (but implemented in composer map)
-      @param delta value from wheel event that describes magnitude and direction (positive /negative number)
-      @param x x-position of mouse cursor (in item coordinates)
-      @param y y-position of mouse cursor (in item coordinates)*/
-    virtual void zoomContent( int delta, double x, double y ) { Q_UNUSED( delta ); Q_UNUSED( x ); Q_UNUSED( y ); }
+     * @param delta value from wheel event that describes direction (positive /negative number)
+     * @param x x-position of mouse cursor (in item coordinates)
+     * @param y y-position of mouse cursor (in item coordinates)
+     * @deprecated use zoomContent( double, QPointF, ZoomMode ) instead
+    */
+    Q_DECL_DEPRECATED virtual void zoomContent( int delta, double x, double y ) { Q_UNUSED( delta ); Q_UNUSED( x ); Q_UNUSED( y ); }
+
+    /**Zoom content of item. Does nothing per default (but implemented in composer map)
+     * @param factor zoom factor, where > 1 results in a zoom in and < 1 results in a zoom out
+     * @param point item point for zoom center
+     * @param mode zoom mode
+     * @note added in QGIS 2.5
+    */
+    virtual void zoomContent( const double factor, const QPointF point, const ZoomMode mode = QgsComposerItem::Zoom ) { Q_UNUSED( factor ); Q_UNUSED( point ); Q_UNUSED( mode ); }
 
     /**Gets the page the item is currently on.
      * @returns page number for item

src/core/composer/qgscomposeritemcommand.h

@@ -119,7 +119,8 @@ class CORE_EXPORT QgsComposerMergeCommand: public QgsComposerItemCommand
       ItemOutlineWidth,
       ItemMove,
       ItemRotation,
-      ItemTransparency
+      ItemTransparency,
+      ItemZoomContent
     };
 
     QgsComposerMergeCommand( Context c, QgsComposerItem* item, const QString& text );

src/core/composer/qgscomposermap.cpp

@@ -605,55 +605,63 @@ void QgsComposerMap::moveContent( double dx, double dy )
 
 void QgsComposerMap::zoomContent( int delta, double x, double y )
 {
-  if ( mDrawing )
+  QSettings settings;
+
+  //read zoom mode
+  QgsComposerItem::ZoomMode zoomMode = ( QgsComposerItem::ZoomMode )settings.value( "/qgis/wheel_action", 2 ).toInt();
+  if ( zoomMode == QgsComposerItem::NoZoom )
   {
+    //do nothing
     return;
   }
 
-  QSettings settings;
+  double zoomFactor = settings.value( "/qgis/zoom_factor", 2.0 ).toDouble();
+  zoomFactor = delta > 0 ? zoomFactor : 1 / zoomFactor;
 
-  //read zoom mode
-  //0: zoom, 1: zoom and recenter, 2: zoom to cursor, 3: nothing
-  int zoomMode = settings.value( "/qgis/wheel_action", 2 ).toInt();
-  if ( zoomMode == 3 ) //do nothing
+  zoomContent( zoomFactor, QPointF( x, y ), zoomMode );
+}
+
+void QgsComposerMap::zoomContent( const double factor, const QPointF point, const ZoomMode mode )
+{
+  if ( mDrawing )
   {
     return;
   }
 
-  double zoomFactor = settings.value( "/qgis/zoom_factor", 2.0 ).toDouble();
+  if ( mode == QgsComposerItem::NoZoom )
+  {
+    //do nothing
+    return;
+  }
+
+  //find out map coordinates of position
+  double mapX = currentMapExtent()->xMinimum() + ( point.x() / rect().width() ) * ( currentMapExtent()->xMaximum() - currentMapExtent()->xMinimum() );
+  double mapY = currentMapExtent()->yMinimum() + ( 1 - ( point.y() / rect().height() ) ) * ( currentMapExtent()->yMaximum() - currentMapExtent()->yMinimum() );
 
   //find out new center point
   double centerX = ( currentMapExtent()->xMaximum() + currentMapExtent()->xMinimum() ) / 2;
   double centerY = ( currentMapExtent()->yMaximum() + currentMapExtent()->yMinimum() ) / 2;
 
-  if ( zoomMode != 0 )
+  if ( mode != QgsComposerItem::Zoom )
   {
-    //find out map coordinates of mouse position
-    double mapMouseX = currentMapExtent()->xMinimum() + ( x / rect().width() ) * ( currentMapExtent()->xMaximum() - currentMapExtent()->xMinimum() );
-    double mapMouseY = currentMapExtent()->yMinimum() + ( 1 - ( y / rect().height() ) ) * ( currentMapExtent()->yMaximum() - currentMapExtent()->yMinimum() );
-    if ( zoomMode == 1 ) //zoom and recenter
+    if ( mode == QgsComposerItem::ZoomRecenter )
     {
-      centerX = mapMouseX;
-      centerY = mapMouseY;
+      centerX = mapX;
+      centerY = mapY;
     }
-    else if ( zoomMode == 2 ) //zoom to cursor
+    else if ( mode == QgsComposerItem::ZoomToPoint )
     {
-      centerX = mapMouseX + ( centerX - mapMouseX ) * ( 1.0 / zoomFactor );
-      centerY = mapMouseY + ( centerY - mapMouseY ) * ( 1.0 / zoomFactor );
+      centerX = mapX + ( centerX - mapX ) * ( 1.0 / factor );
+      centerY = mapY + ( centerY - mapY ) * ( 1.0 / factor );
     }
   }
 
   double newIntervalX, newIntervalY;
 
-  if ( delta > 0 )
-  {
-    newIntervalX = ( currentMapExtent()->xMaximum() - currentMapExtent()->xMinimum() ) / zoomFactor;
-    newIntervalY = ( currentMapExtent()->yMaximum() - currentMapExtent()->yMinimum() ) / zoomFactor;
-  }
-  else if ( delta < 0 )
+  if ( factor > 0 )
   {
-    newIntervalX = ( currentMapExtent()->xMaximum() - currentMapExtent()->xMinimum() ) * zoomFactor;
-    newIntervalY = ( currentMapExtent()->yMaximum() - currentMapExtent()->yMinimum() ) * zoomFactor;
+    newIntervalX = ( currentMapExtent()->xMaximum() - currentMapExtent()->xMinimum() ) / factor;
+    newIntervalY = ( currentMapExtent()->yMaximum() - currentMapExtent()->yMinimum() ) / factor;
   }
   else //no need to zoom
   {

src/core/composer/qgscomposermap.h

@@ -170,10 +170,20 @@ class CORE_EXPORT QgsComposerMap : public QgsComposerItem
     void moveContent( double dx, double dy );
 
     /**Zoom content of map
-     @param delta value from wheel event that describes magnitude and direction (positive /negative number)
-    @param x x-coordinate of mouse position in item coordinates
-    @param y y-coordinate of mouse position in item coordinates*/
-    void zoomContent( int delta, double x, double y );
+     * @param delta value from wheel event that describes direction (positive /negative number)
+     * @param x x-position of mouse cursor (in item coordinates)
+     * @param y y-position of mouse cursor (in item coordinates)
+     * @deprecated use zoomContent( double, QPointF, ZoomMode ) instead
+    */
+    Q_DECL_DEPRECATED void zoomContent( int delta, double x, double y );
+
+    /**Zoom content of item. Does nothing per default (but implemented in composer map)
+     * @param factor zoom factor, where > 1 results in a zoom in and < 1 results in a zoom out
+     * @param point item point for zoom center
+     * @param mode zoom mode
+     * @note added in QGIS 2.5
+    */
+    virtual void zoomContent( const double factor, const QPointF point, const ZoomMode mode = QgsComposerItem::Zoom );
 
     /**Sets new scene rectangle bounds and recalculates hight and extent*/
     void setSceneRect( const QRectF& rectangle );

src/gui/qgscomposerview.cpp

@@ -1558,9 +1558,26 @@ void QgsComposerView::wheelEvent( QWheelEvent* event )
     {
       if ( theItem->isSelected() )
       {
+        QSettings settings;
+        //read zoom mode
+        QgsComposerItem::ZoomMode zoomMode = ( QgsComposerItem::ZoomMode )settings.value( "/qgis/wheel_action", 2 ).toInt();
+        if ( zoomMode == QgsComposerItem::NoZoom )
+        {
+          //do nothing
+          return;
+        }
+
+        double zoomFactor = settings.value( "/qgis/zoom_factor", 2.0 ).toDouble();
+        if ( event->modifiers() & Qt::ControlModifier )
+        {
+          //holding ctrl while wheel zooming results in a finer zoom
+          zoomFactor = 1.0 + ( zoomFactor - 1.0 ) / 20.0;
+        }
+        zoomFactor = event->delta() > 0 ? zoomFactor : 1 / zoomFactor;
+
         QPointF itemPoint = theItem->mapFromScene( scenePoint );
-        theItem->beginCommand( tr( "Zoom item content" ) );
-        theItem->zoomContent( event->delta(), itemPoint.x(), itemPoint.y() );
+        theItem->beginCommand( tr( "Zoom item content" ), QgsComposerMergeCommand::ItemZoomContent );
+        theItem->zoomContent( zoomFactor, itemPoint, zoomMode );
         theItem->endCommand();
       }
     }