Fix automatic wire tool in gridless mode

The automatic wire tool was not working in the gridless mode because the
grid snapping on/off logic present in `EE_GRID_HELPER`, based on the
value of `m_enableGrid`, was not taking into account that another check,
but for the global KiCad setting, would be performed in the `Align()`
method, which is inherited from `GRID_HELPER`.

I've modified all tests of `m_enableGrid` value to also take the global
setting into account, and moved checks for it to `Align()` method, as
it's more consistent this way.

I've also removed an override of the `Align()` method in the
`PCB_GRID_HELPER` class, as it was made redundant by my changes.

Fixes https://gitlab.com/kicad/code/kicad/issues/7402

common/tool/grid_helper.cpp

@@ -94,7 +94,7 @@ VECTOR2I GRID_HELPER::AlignGrid( const VECTOR2I& aPoint ) const
 
 VECTOR2I GRID_HELPER::Align( const VECTOR2I& aPoint ) const
 {
-    if( !m_toolMgr->GetView()->GetGAL()->GetGridSnapping() )
+    if( !canUseGrid() )
         return aPoint;
 
     VECTOR2I nearest = AlignGrid( aPoint );

eeschema/tools/ee_grid_helper.cpp

@@ -135,7 +135,7 @@ VECTOR2I EE_GRID_HELPER::BestSnapAnchor( const VECTOR2I& aOrigin, int aLayer,
         computeAnchors( item, aOrigin );
 
     ANCHOR*  nearest = nearestAnchor( aOrigin, SNAPPABLE, aLayer );
-    VECTOR2I nearestGrid = m_enableGrid ? Align( aOrigin ) : aOrigin;
+    VECTOR2I nearestGrid = Align( aOrigin );
 
     if( m_enableSnapLine && m_snapItem && m_skipPoint != VECTOR2I( m_viewSnapLine.GetPosition() ) )
     {
@@ -153,14 +153,14 @@ VECTOR2I EE_GRID_HELPER::BestSnapAnchor( const VECTOR2I& aOrigin, int aLayer,
             snapLineY = true;
         }
 
-        if( m_enableGrid && std::abs( nearestGrid.x - aOrigin.x ) < snapDist.x )
+        if( canUseGrid() && std::abs( nearestGrid.x - aOrigin.x ) < snapDist.x )
         {
             pt.x = nearestGrid.x;
             snapDist.x = std::abs( nearestGrid.x - aOrigin.x );
             snapLineX = false;
         }
 
-        if( m_enableGrid && std::abs( nearestGrid.y - aOrigin.y ) < snapDist.y )
+        if( canUseGrid() && std::abs( nearestGrid.y - aOrigin.y ) < snapDist.y )
         {
             pt.y = nearestGrid.y;
             snapDist.y = std::abs( nearestGrid.y - aOrigin.y );
@@ -172,24 +172,27 @@ VECTOR2I EE_GRID_HELPER::BestSnapAnchor( const VECTOR2I& aOrigin, int aLayer,
 
     if( m_enableSnap && nearest && nearest->Distance( aOrigin ) < snapDist.EuclideanNorm() )
     {
-        pt = nearest->pos;
-        snapDist.x = std::abs( nearest->pos.x - aOrigin.x );
-        snapDist.y = std::abs( nearest->pos.y - aOrigin.y );
-        snapLineX = snapLineY = false;
-        snapPoint = true;
 
-        if( m_enableGrid && ( nearestGrid - aOrigin ).EuclideanNorm() < snapDist.EuclideanNorm() )
+        if( canUseGrid() && ( nearestGrid - aOrigin ).EuclideanNorm() < snapDist.EuclideanNorm() )
         {
             pt = nearestGrid;
             snapDist.x = std::abs( nearestGrid.x - aOrigin.x );
             snapDist.y = std::abs( nearestGrid.y - aOrigin.y );
             snapPoint = false;
         }
+        else
+        {
+            pt = nearest->pos;
+            snapDist.x = std::abs( nearest->pos.x - aOrigin.x );
+            snapDist.y = std::abs( nearest->pos.y - aOrigin.y );
+            snapPoint = true;
+        }
 
+        snapLineX = snapLineY = false;
         gridChecked = true;
     }
 
-    if( m_enableGrid && !gridChecked )
+    if( canUseGrid() && !gridChecked )
         pt = nearestGrid;
 
     if( snapLineX || snapLineY )
@@ -223,7 +226,6 @@ VECTOR2I EE_GRID_HELPER::BestSnapAnchor( const VECTOR2I& aOrigin, int aLayer,
     return pt;
 }
 
-
 SCH_ITEM* EE_GRID_HELPER::GetSnapped() const
 {
     if( !m_snapItem )
@@ -289,7 +291,7 @@ void EE_GRID_HELPER::computeAnchors( SCH_ITEM *aItem, const VECTOR2I &aRefPos, b
 
     if( SCH_LINE* line = dyn_cast<SCH_LINE*>( aItem ) )
     {
-        VECTOR2I pt = m_enableGrid ? Align( aRefPos ) : aRefPos;
+        VECTOR2I pt = Align( aRefPos );
 
         if( line->GetStartPoint().x == line->GetEndPoint().x )
         {

include/tool/grid_helper.h

@@ -24,6 +24,7 @@
 #ifndef GRID_HELPER_H
 #define GRID_HELPER_H
 
+#include <tool/tool_manager.h>
 #include <vector>
 #include <math/vector2d.h>
 #include <origin_viewitem.h>
@@ -113,6 +114,15 @@ protected:
         m_anchors.clear();
     }
 
+    /**
+     * Check whether it is possible to use the grid -- this depends both on local grid helper
+     * settings and global (tool manager) KiCad settings.
+     */
+    bool canUseGrid() const
+    {
+        return m_enableGrid && m_toolMgr->GetView()->GetGAL()->GetGridSnapping();
+    }
+
 protected:
     std::vector<ANCHOR>    m_anchors;
 

pcbnew/tools/pcb_grid_helper.h

@@ -46,14 +46,6 @@ public:
      */
     BOARD_ITEM* GetSnapped() const;
 
-    VECTOR2I Align( const VECTOR2I& aPoint ) const override
-    {
-        if( !m_enableGrid )
-            return aPoint;
-
-        return GRID_HELPER::Align( aPoint );
-    }
-
     VECTOR2I AlignToSegment ( const VECTOR2I& aPoint, const SEG& aSeg );
 
     VECTOR2I BestDragOrigin( const VECTOR2I& aMousePos, std::vector<BOARD_ITEM*>& aItem );