Second pass at fixing warping and grids

First attempt caused additional problems for #21535

Fixes https://gitlab.com/kicad/code/kicad/-/issues/18196

(cherry picked from commit 2cdeb0cd7c618d2ff3f5dc95c53a6b217a55af9d)

common/tool/grid_helper.cpp

@@ -182,35 +182,38 @@ void GRID_HELPER::SetAuxAxes( bool aEnable, const VECTOR2I& aOrigin )
 
 VECTOR2I GRID_HELPER::AlignGrid( const VECTOR2I& aPoint ) const
 {
-    return computeNearest( aPoint, GetGrid() );
+    return computeNearest( aPoint, GetGrid(), GetOrigin() );
 }
 
 
-VECTOR2I GRID_HELPER::AlignGrid( const VECTOR2I& aPoint, const VECTOR2D& aGrid ) const
+VECTOR2I GRID_HELPER::AlignGrid( const VECTOR2I& aPoint, const VECTOR2D& aGrid,
+                                 const VECTOR2D& aOffset ) const
 {
-    return computeNearest( aPoint, aGrid );
+    return computeNearest( aPoint, aGrid, aOffset );
 }
 
 
-VECTOR2I GRID_HELPER::computeNearest( const VECTOR2I& aPoint, const VECTOR2I& aGrid ) const
+VECTOR2I GRID_HELPER::computeNearest( const VECTOR2I& aPoint, const VECTOR2I& aGrid,
+                                      const VECTOR2I& aOffset ) const
 {
-    return VECTOR2I( KiROUND( static_cast<double>( aPoint.x ) / aGrid.x ) * aGrid.x,
-                     KiROUND( static_cast<double>( aPoint.y ) / aGrid.y ) * aGrid.y );
+    return VECTOR2I( KiROUND( (double) ( aPoint.x - aOffset.x ) / aGrid.x ) * aGrid.x + aOffset.x,
+                     KiROUND( (double) ( aPoint.y - aOffset.y ) / aGrid.y ) * aGrid.y + aOffset.y );
 }
 
 
 VECTOR2I GRID_HELPER::Align( const VECTOR2I& aPoint ) const
 {
-    return Align( aPoint, GetGrid() );
+    return Align( aPoint, GetGrid(), GetOrigin() );
 }
 
 
-VECTOR2I GRID_HELPER::Align( const VECTOR2I& aPoint, const VECTOR2D& aGrid ) const
+VECTOR2I GRID_HELPER::Align( const VECTOR2I& aPoint, const VECTOR2D& aGrid,
+                             const VECTOR2D& aOffset ) const
 {
     if( !canUseGrid() )
         return aPoint;
 
-    VECTOR2I nearest = AlignGrid( aPoint, aGrid );
+    VECTOR2I nearest = AlignGrid( aPoint, aGrid, aOffset );
 
     if( !m_auxAxis )
         return nearest;

include/tool/grid_helper.h

@@ -64,19 +64,21 @@ public:
 
     virtual VECTOR2I Align( const VECTOR2I& aPoint, GRID_HELPER_GRIDS aGrid ) const
     {
-        return Align( aPoint, GetGridSize( aGrid ) );
+        return Align( aPoint, GetGridSize( aGrid ), GetOrigin() );
     }
 
     virtual VECTOR2I AlignGrid( const VECTOR2I& aPoint, GRID_HELPER_GRIDS aGrid ) const
     {
-        return AlignGrid( aPoint, GetGridSize( aGrid ) );
+        return AlignGrid( aPoint, GetGridSize( aGrid ), GetOrigin() );
     }
 
     virtual VECTOR2I Align( const VECTOR2I& aPoint ) const;
-    virtual VECTOR2I Align( const VECTOR2I& aPoint, const VECTOR2D& aGrid ) const;
+    virtual VECTOR2I Align( const VECTOR2I& aPoint, const VECTOR2D& aGrid,
+                            const VECTOR2D& aOffset ) const;
 
     VECTOR2I AlignGrid( const VECTOR2I& aPoint ) const;
-    VECTOR2I AlignGrid( const VECTOR2I& aPoint, const VECTOR2D& aGrid ) const;
+    VECTOR2I AlignGrid( const VECTOR2I& aPoint, const VECTOR2D& aGrid,
+                        const VECTOR2D& aOffset ) const;
 
     /**
      * Gets the coarsest grid that applies to a selecion of items.
@@ -197,7 +199,8 @@ protected:
      */
     bool canUseGrid() const;
 
-    VECTOR2I computeNearest( const VECTOR2I& aPoint, const VECTOR2I& aGrid ) const;
+    VECTOR2I computeNearest( const VECTOR2I& aPoint, const VECTOR2I& aGrid,
+                             const VECTOR2I& aOffset ) const;
 
 protected:
     void showConstructionGeometry( bool aShow );

pcbnew/tools/edit_tool_move_fct.cpp

@@ -667,15 +667,30 @@ bool EDIT_TOOL::doMoveSelection( const TOOL_EVENT& aEvent, BOARD_COMMIT* aCommit
                     }
                     else
                     {
-                        // Check if user wants to warp the mouse to origin of moved object
-                        if( !editFrame->GetMoveWarpsCursor() )
-                            m_cursor = originalCursorPos; // No, so use original mouse pos instead
+                        VECTOR2I snapped = grid.Align( m_cursor, grid.GetSelectionGrid( selection ) );
+                        VECTOR2I delta = snapped - m_cursor;
 
-                        selection.SetReferencePoint( m_cursor );
-                        grid.SetAuxAxes( true, m_cursor );
+                        if( delta.x || delta.y )
+                        {
+                            for( BOARD_ITEM* item : sel_items )
+                            {
+                                if( item->GetParent() && item->GetParent()->IsSelected() )
+                                    continue;
+
+                                item->Move( delta );
+                            }
+                        }
+
+                        selection.SetReferencePoint( snapped );
+                        grid.SetAuxAxes( true, snapped );
+
+                        if( !editFrame->GetMoveWarpsCursor() )
+                            m_cursor = originalCursorPos;
+                        else
+                            m_cursor = snapped;
                     }
 
-                    originalPos = m_cursor;
+                    originalPos = selection.GetReferencePoint();
                 }
 
                 // Update variables for bounding box collision calculations