Allow deletion of zone cutout areas

ADDED: Ability to delete zone cutout areas

Fixes https://gitlab.com/kicad/code/kicad/issues/4188

libs/kimath/include/geometry/shape_poly_set.h

@@ -437,6 +437,13 @@ class SHAPE_POLY_SET : public SHAPE
 
         SHAPE_POLY_SET();
 
+        /**
+         * Construct a SHAPE_POLY_SET with the first outline given by aOutline.
+         *
+         * @param aOutline is a closed outline
+         */
+        SHAPE_POLY_SET( const SHAPE_LINE_CHAIN& aOutline );
+
         /**
          * Copy constructor SHAPE_POLY_SET
          * Performs a deep copy of \p aOther into \p this.

libs/kimath/src/geometry/shape_poly_set.cpp

@@ -60,6 +60,13 @@ SHAPE_POLY_SET::SHAPE_POLY_SET() :
 }
 
 
+SHAPE_POLY_SET::SHAPE_POLY_SET( const SHAPE_LINE_CHAIN& aOutline ) :
+    SHAPE( SH_POLY_SET )
+{
+    AddOutline( aOutline );
+}
+
+
 SHAPE_POLY_SET::SHAPE_POLY_SET( const SHAPE_POLY_SET& aOther, bool aDeepCopy ) :
     SHAPE( SH_POLY_SET ), m_polys( aOther.m_polys )
 {

pcbnew/class_zone.cpp

@@ -689,6 +689,31 @@ bool ZONE_CONTAINER::HitTestFilledArea( const wxPoint& aRefPos ) const
 }
 
 
+bool ZONE_CONTAINER::HitTestCutout( const VECTOR2I& aRefPos, int* aOutlineIdx, int* aHoleIdx ) const
+{
+    // Iterate over each outline polygon in the zone and then iterate over
+    // each hole it has to see if the point is in it.
+    for( int i = 0; i < m_Poly->OutlineCount(); i++ )
+    {
+        for( int j = 0; j < m_Poly->HoleCount( i ); j++ )
+        {
+            if( m_Poly->Hole( i, j ).PointInside( aRefPos ) )
+            {
+                if( aOutlineIdx )
+                    *aOutlineIdx = i;
+
+                if( aHoleIdx )
+                    *aHoleIdx = j;
+
+                return true;
+            }
+        }
+    }
+
+    return false;
+}
+
+
 void ZONE_CONTAINER::GetMsgPanelInfo( EDA_UNITS aUnits, std::vector<MSG_PANEL_ITEM>& aList )
 {
     wxString msg;
@@ -887,6 +912,21 @@ ZONE_CONNECTION ZONE_CONTAINER::GetPadConnection( D_PAD* aPad ) const
 }
 
 
+void ZONE_CONTAINER::RemoveCutout( int aOutlineIdx, int aHoleIdx )
+{
+    // Ensure the requested cutout is valid
+    if( m_Poly->OutlineCount() < aOutlineIdx || m_Poly->HoleCount( aOutlineIdx ) < aHoleIdx )
+        return;
+
+    SHAPE_POLY_SET cutPoly( m_Poly->Hole( aOutlineIdx, aHoleIdx ) );
+
+    // Add the cutout back to the zone
+    m_Poly->BooleanAdd( cutPoly, SHAPE_POLY_SET::PM_FAST );
+
+    SetNeedRefill( true );
+}
+
+
 void ZONE_CONTAINER::AddPolygon( const SHAPE_LINE_CHAIN& aPolygon )
 {
     wxASSERT( aPolygon.IsClosed() );

pcbnew/class_zone.h

@@ -283,6 +283,24 @@ public:
      */
     bool HitTestFilledArea( const wxPoint& aRefPos ) const;
 
+    /**
+     * Tests if the given point is contained within a cutout of the zone.
+     *
+     * @param aRefPos is the point to test
+     * @param aOutlineIdx is the index of the outline containing the cutout
+     * @param aHoleIdx is the index of the hole
+     * @return true if aRefPos is inside a zone cutout
+     */
+    bool HitTestCutout( const VECTOR2I& aRefPos, int* aOutlineIdx = nullptr,
+            int* aHoleIdx = nullptr ) const;
+
+    bool HitTestCutout( const wxPoint& aRefPos, int* aOutlineIdx = nullptr,
+            int* aHoleIdx = nullptr ) const
+    {
+        return HitTestCutout( VECTOR2I( aRefPos.x, aRefPos.y ), aOutlineIdx, aHoleIdx );
+    }
+
+
     /**
      * Some intersecting zones, despite being on the same layer with the same net, cannot be
      * merged due to other parameters such as fillet radius.  The copper pour will end up
@@ -618,6 +636,14 @@ public:
     void SetFilledPolysUseThickness( bool aOption ) { m_FilledPolysUseThickness = aOption; }
 
 
+    /**
+     * Remove a cutout from the zone.
+     *
+     * @param aOutlineIdx is the zone outline the hole belongs to
+     * @param aHoleIdx is the hole in the outline to remove
+     */
+    void RemoveCutout( int aOutlineIdx, int aHoleIdx );
+
     /**
      * add a polygon to the zone outline
      * if the zone outline is empty, this is the main outline

pcbnew/tools/edit_tool.cpp

@@ -55,6 +55,7 @@ using namespace std::placeholders;
 #include <dialogs/dialog_track_via_properties.h>
 #include <preview_items/ruler_item.h>
 #include <board_commit.h>
+#include <zone_filler.h>
 
 
 void EditToolSelectionFilter( GENERAL_COLLECTOR& aCollector, int aFlags )
@@ -925,6 +926,48 @@ int EDIT_TOOL::Remove( const TOOL_EVENT& aEvent )
             }
             break;
 
+        case PCB_ZONE_AREA_T:
+            // We process the zones special so that cutouts can be deleted when the delete tool
+            // is called from inside a cutout when the zone is selected.
+            {
+                // Only interact with cutouts when deleting and a single item is selected
+                if( !isCut && selectionCopy.GetSize() == 1 )
+                {
+                    VECTOR2I curPos = getViewControls()->GetCursorPosition();
+                    auto     zone   = static_cast<ZONE_CONTAINER*>( item );
+
+                    int outlineIdx, holeIdx;
+
+                    if( zone->HitTestCutout( curPos, &outlineIdx, &holeIdx ) )
+                    {
+                        // Remove the cutout
+                        m_commit->Modify( zone );
+                        zone->RemoveCutout( outlineIdx, holeIdx );
+
+                        std::vector<ZONE_CONTAINER*> toFill;
+                        toFill.emplace_back( zone );
+
+                        // Fill the modified zone
+                        ZONE_FILLER filler( board() );
+                        filler.InstallNewProgressReporter( frame(), _( "Fill Zone" ), 4 );
+                        filler.Fill( toFill );
+
+                        // Update the display
+                        zone->Hatch();
+                        canvas()->Refresh();
+
+                        // Restore the selection on the original zone
+                        m_toolMgr->RunAction( PCB_ACTIONS::selectItem, true, zone );
+
+                        break;
+                    }
+                }
+
+                // Remove the entire zone otherwise
+                m_commit->Remove( item );
+            }
+            break;
+
         default:
             m_commit->Remove( item );
             break;