Add search tolerance to QgsLayoutViewToolSelect

python/core/auto_generated/layout/qgslayout.sip.in

@@ -237,16 +237,20 @@ Note that template UUIDs are only available while a layout is being restored fro
 .. seealso:: :py:func:`itemByUuid`
 %End
 
-    QgsLayoutItem *layoutItemAt( QPointF position, bool ignoreLocked = false ) const;
+    QgsLayoutItem *layoutItemAt( QPointF position, bool ignoreLocked = false, double searchTolerance = 0 ) const;
 %Docstring
 Returns the topmost layout item at a specified ``position``. Ignores paper items.
 If ``ignoreLocked`` is set to ``True`` any locked items will be ignored.
+
+.. versionadded:: 3.32
 %End
 
-    QgsLayoutItem *layoutItemAt( QPointF position, const QgsLayoutItem *belowItem, bool ignoreLocked = false ) const;
+    QgsLayoutItem *layoutItemAt( QPointF position, const QgsLayoutItem *belowItem, bool ignoreLocked = false, double searchTolerance = 0 ) const;
 %Docstring
 Returns the topmost layout item at a specified ``position`` which is below a specified ``item``. Ignores paper items.
 If ``ignoreLocked`` is set to ``True`` any locked items will be ignored.
+
+.. versionadded:: 3.32
 %End
 
     void setUnits( Qgis::LayoutUnit units );

python/gui/auto_generated/layout/qgslayoutviewtoolselect.sip.in

@@ -46,6 +46,13 @@ Constructor for QgsLayoutViewToolSelect.
     void setLayout( QgsLayout *layout );
 %Docstring
 Sets the a ``layout``.
+%End
+
+    double searchToleranceInLayoutUnits();
+%Docstring
+Compute the search tolerance in layout units from the view current scale
+
+.. versionadded:: 3.34
 %End
 
 };

src/core/layout/qgslayout.cpp

@@ -298,15 +298,23 @@ QgsLayoutMultiFrame *QgsLayout::multiFrameByUuid( const QString &uuid, bool incl
   return nullptr;
 }
 
-QgsLayoutItem *QgsLayout::layoutItemAt( QPointF position, const bool ignoreLocked ) const
+QgsLayoutItem *QgsLayout::layoutItemAt( QPointF position, const bool ignoreLocked, double searchTolerance ) const
 {
-  return layoutItemAt( position, nullptr, ignoreLocked );
+  return layoutItemAt( position, nullptr, ignoreLocked, searchTolerance );
 }
 
-QgsLayoutItem *QgsLayout::layoutItemAt( QPointF position, const QgsLayoutItem *belowItem, const bool ignoreLocked ) const
+QgsLayoutItem *QgsLayout::layoutItemAt( QPointF position, const QgsLayoutItem *belowItem, const bool ignoreLocked, double searchTolerance ) const
 {
   //get a list of items which intersect the specified position, in descending z order
-  const QList<QGraphicsItem *> itemList = items( position, Qt::IntersectsItemShape, Qt::DescendingOrder );
+  QList<QGraphicsItem *> itemList;
+  if ( searchTolerance == 0 )
+  {
+    itemList = items( position, Qt::IntersectsItemShape, Qt::DescendingOrder );
+  }
+  else
+  {
+    itemList = items( QRectF( position.x() - searchTolerance, position.y() - searchTolerance, 2 * searchTolerance, 2 * searchTolerance ), Qt::IntersectsItemShape, Qt::DescendingOrder );
+  }
 
   bool foundBelowItem = false;
   for ( QGraphicsItem *graphicsItem : itemList )

src/core/layout/qgslayout.h

@@ -303,14 +303,16 @@ class CORE_EXPORT QgsLayout : public QGraphicsScene, public QgsExpressionContext
     /**
      * Returns the topmost layout item at a specified \a position. Ignores paper items.
      * If \a ignoreLocked is set to TRUE any locked items will be ignored.
+     * \since QGIS 3.32 searchTolerance parameter was added, which can be used to specify a search tolerance in layout units
      */
-    QgsLayoutItem *layoutItemAt( QPointF position, bool ignoreLocked = false ) const;
+    QgsLayoutItem *layoutItemAt( QPointF position, bool ignoreLocked = false, double searchTolerance = 0 ) const;
 
     /**
      * Returns the topmost layout item at a specified \a position which is below a specified \a item. Ignores paper items.
      * If \a ignoreLocked is set to TRUE any locked items will be ignored.
+     * \since QGIS 3.32 searchTolerance parameter was added, which can be used to specify a search tolerance in layout units
      */
-    QgsLayoutItem *layoutItemAt( QPointF position, const QgsLayoutItem *belowItem, bool ignoreLocked = false ) const;
+    QgsLayoutItem *layoutItemAt( QPointF position, const QgsLayoutItem *belowItem, bool ignoreLocked = false, double searchTolerance = 0 ) const;
 
     /**
      * Sets the native measurement \a units for the layout. These also form the default unit

src/gui/layout/qgslayoutmousehandles.cpp

@@ -99,7 +99,17 @@ void QgsLayoutMouseHandles::setViewportCursor( Qt::CursorShape cursor )
 
 QList<QGraphicsItem *> QgsLayoutMouseHandles::sceneItemsAtPoint( QPointF scenePoint )
 {
-  QList< QGraphicsItem * > items = mLayout->items( scenePoint );
+  QList< QGraphicsItem * > items;
+  if ( QgsLayoutViewToolSelect *tool = qobject_cast< QgsLayoutViewToolSelect *>( mView->tool() ) )
+  {
+    const double searchTolerance = tool->searchToleranceInLayoutUnits();
+    const QRectF area( scenePoint.x() - searchTolerance, scenePoint.y() - searchTolerance, 2 * searchTolerance, 2 * searchTolerance );
+    items = mLayout->items( area );
+  }
+  else
+  {
+    items = mLayout->items( scenePoint );
+  }
   items.erase( std::remove_if( items.begin(), items.end(), []( QGraphicsItem * item )
   {
     return !dynamic_cast<QgsLayoutItem *>( item );

src/gui/layout/qgslayoutviewtoolselect.cpp

@@ -22,6 +22,9 @@
 #include "qgslayoutitemgroup.h"
 
 
+const double QgsLayoutViewToolSelect::sSearchToleranceInMillimeters = 2.0;
+
+
 QgsLayoutViewToolSelect::QgsLayoutViewToolSelect( QgsLayoutView *view )
   : QgsLayoutViewTool( view, tr( "Select" ) )
 {
@@ -94,19 +97,19 @@ void QgsLayoutViewToolSelect::layoutPressEvent( QgsLayoutViewMouseEvent *event )
   if ( previousSelectedItem )
   {
     //select highest item just below previously selected item at position of event
-    selectedItem = layout()->layoutItemAt( event->layoutPoint(), previousSelectedItem, true );
+    selectedItem = layout()->layoutItemAt( event->layoutPoint(), previousSelectedItem, true, searchToleranceInLayoutUnits() );
 
     //if we didn't find a lower item we'll use the top-most as fall-back
     //this duplicates mapinfo/illustrator/etc behavior where ctrl-clicks are "cyclic"
     if ( !selectedItem )
     {
-      selectedItem = layout()->layoutItemAt( event->layoutPoint(), true );
+      selectedItem = layout()->layoutItemAt( event->layoutPoint(), true, searchToleranceInLayoutUnits() );
     }
   }
   else
   {
     //select topmost item at position of event
-    selectedItem = layout()->layoutItemAt( event->layoutPoint(), true );
+    selectedItem = layout()->layoutItemAt( event->layoutPoint(), true, searchToleranceInLayoutUnits() );
   }
 
   // if selected item is in a group, we actually get the top-level group it's part of
@@ -167,6 +170,17 @@ void QgsLayoutViewToolSelect::layoutMoveEvent( QgsLayoutViewMouseEvent *event )
   }
   else
   {
+    if ( !mMouseHandles->isDragging() && !mMouseHandles->isResizing() )
+    {
+      if ( layout()->layoutItemAt( event->layoutPoint(), true, searchToleranceInLayoutUnits() ) )
+      {
+        view()->viewport()->setCursor( Qt::SizeAllCursor );
+      }
+      else
+      {
+        view()->viewport()->setCursor( Qt::ArrowCursor );
+      }
+    }
     event->ignore();
   }
 }
@@ -219,7 +233,10 @@ void QgsLayoutViewToolSelect::layoutReleaseEvent( QgsLayoutViewMouseEvent *event
   //find all items in rect
   QList<QGraphicsItem *> itemList;
   if ( wasClick )
-    itemList = layout()->items( rect.center(), selectionMode );
+  {
+    const double tolerance = searchToleranceInLayoutUnits();
+    itemList = layout()->items( QRectF( rect.center().x() - tolerance, rect.center().y() - tolerance, 2 * tolerance, 2 * tolerance ), selectionMode );
+  }
   else
     itemList = layout()->items( rect, selectionMode );
 
@@ -323,4 +340,9 @@ void QgsLayoutViewToolSelect::setLayout( QgsLayout *layout )
   mMouseHandles->setZValue( QgsLayout::ZMouseHandles );
   layout->addItem( mMouseHandles );
 }
+double QgsLayoutViewToolSelect::searchToleranceInLayoutUnits()
+{
+  const double pixelsPerMm = view()->physicalDpiX() / 25.4;
+  return sSearchToleranceInMillimeters * pixelsPerMm / view()->transform().m11();
+}
 ///@endcond

src/gui/layout/qgslayoutviewtoolselect.h

@@ -61,6 +61,12 @@ class GUI_EXPORT QgsLayoutViewToolSelect : public QgsLayoutViewTool
     //! Sets the a \a layout.
     void setLayout( QgsLayout *layout );
 
+    /**
+     * Compute the search tolerance in layout units from the view current scale
+     * \since QGIS 3.34
+     */
+    double searchToleranceInLayoutUnits();
+
   private:
 
     bool mIsSelecting = false;
@@ -75,6 +81,9 @@ class GUI_EXPORT QgsLayoutViewToolSelect : public QgsLayoutViewTool
     QPointF mRubberBandStartPos;
 
     QPointer< QgsLayoutMouseHandles > mMouseHandles; //owned by scene
+
+    //! Search tolerance in millimeters for selecting items
+    static const double sSearchToleranceInMillimeters;
 };
 
 #endif // QGSLAYOUTVIEWTOOLSELECT_H

src/gui/qgsgraphicsviewmousehandles.cpp

@@ -465,7 +465,6 @@ void QgsGraphicsViewMouseHandles::mousePressEvent( QGraphicsSceneMouseEvent *eve
 
   //save current cursor position
   mMouseMoveStartPos = event->lastScenePos();
-  mLastMouseEventPos = event->lastScenePos();
   //save current item geometry
   mBeginMouseEventPos = event->lastScenePos();
   mBeginHandlePos = scenePos();
@@ -526,8 +525,6 @@ void QgsGraphicsViewMouseHandles::mouseMoveEvent( QGraphicsSceneMouseEvent *even
     //resize from center if alt depressed
     resizeMouseMove( event->lastScenePos(), event->modifiers() & Qt::ShiftModifier, event->modifiers() & Qt::AltModifier );
   }
-
-  mLastMouseEventPos = event->lastScenePos();
 }
 
 void QgsGraphicsViewMouseHandles::mouseReleaseEvent( QGraphicsSceneMouseEvent *event )

src/gui/qgsgraphicsviewmousehandles.h

@@ -216,9 +216,6 @@ class GUI_EXPORT QgsGraphicsViewMouseHandles: public QObject, public QGraphicsRe
     //! Start point of the last mouse move action (in scene coordinates)
     QPointF mMouseMoveStartPos;
 
-    //! Position of the last mouse move event (in scene coordinates)
-    QPointF mLastMouseEventPos;
-
     MouseAction mCurrentMouseMoveAction = NoAction;
 
     //! True if user is currently dragging items