Re-enable grid snap line

This was accidentally disabled by 4039b7da6b

common/tool/grid_helper.cpp

@@ -41,7 +41,7 @@ GRID_HELPER::GRID_HELPER( TOOL_MANAGER* aToolMgr ) :
     m_enableSnap = true;
     m_enableSnapLine = true;
     m_enableGrid = true;
-    m_snapItem = nullptr;
+    m_snapItem = std::nullopt;
 }
 
 

eeschema/tools/ee_grid_helper.cpp

@@ -236,7 +236,7 @@ VECTOR2I EE_GRID_HELPER::BestSnapAnchor( const VECTOR2I& aOrigin, GRID_HELPER_GR
     }
     else if( snapPoint )
     {
-        m_snapItem = nearest;
+        m_snapItem = *nearest;
         m_viewSnapPoint.SetPosition( pt );
         m_viewSnapLine.SetPosition( pt );
 

include/tool/grid_helper.h

@@ -154,7 +154,6 @@ protected:
     void clearAnchors()
     {
         m_anchors.clear();
-        m_snapItem = nullptr;
     }
 
     /**
@@ -177,7 +176,7 @@ protected:
     bool                    m_enableSnap;     // Allow snapping to other items on the layers
     bool                    m_enableGrid;     // If true, allow snapping to grid
     bool                    m_enableSnapLine; // Allow drawing lines from snap points
-    ANCHOR*                 m_snapItem;       // Pointer to the currently snapped item in m_anchors
+    std::optional<ANCHOR>   m_snapItem;       // Pointer to the currently snapped item in m_anchors
                                               //   (NULL if not snapped)
     VECTOR2I                m_skipPoint;      // When drawing a line, we avoid snapping to the
                                               //   source point

pcbnew/tools/pcb_grid_helper.cpp

@@ -370,12 +370,12 @@ VECTOR2I PCB_GRID_HELPER::BestSnapAnchor( const VECTOR2I& aOrigin, const LSET& a
             else
                 m_toolMgr->GetView()->SetVisible( &m_viewSnapPoint, true );
 
-            m_snapItem = nearest;
+            m_snapItem = *nearest;
             return nearest->pos;
         }
     }
 
-    m_snapItem = nullptr;
+    m_snapItem = std::nullopt;
     m_toolMgr->GetView()->SetVisible( &m_viewSnapPoint, false );
     m_toolMgr->GetView()->SetVisible( &m_viewSnapLine, false );
     return nearestGrid;

pcbnew/tools/pcb_grid_helper.h

@@ -30,6 +30,7 @@
 
 #include <pcb_item_containers.h>
 #include <tool/grid_helper.h>
+#include <board.h>
 
 class LSET;
 class SHAPE_ARC;
@@ -37,7 +38,7 @@ class TOOL_MANAGER;
 struct MAGNETIC_SETTINGS;
 struct PCB_SELECTION_FILTER_OPTIONS;
 
-class PCB_GRID_HELPER : public GRID_HELPER
+class PCB_GRID_HELPER : public GRID_HELPER, public BOARD_LISTENER
 {
 public:
 
@@ -66,6 +67,14 @@ public:
 
     VECTOR2I AlignToNearestPad( const VECTOR2I& aMousePos, std::deque<PAD*>& aPads );
 
+    virtual void OnBoardItemRemoved( BOARD& aBoard, BOARD_ITEM* aBoardItem ) override
+    {
+        if( m_snapItem->item == aBoardItem )
+        {
+            m_snapItem = std::nullopt;
+        }
+    }
+
     /**
      * Chooses the "best" snap anchor around the given point, optionally taking layers from
      * the reference item.  The reference item will not be snapped to (it is being dragged or