Pcbnew: handle connected copper circle points

Fixes: https://gitlab.com/kicad/code/kicad/-/issues/18774

libs/kimath/include/geometry/shape_utils.h

@@ -41,10 +41,12 @@
 
 #include <geometry/direction45.h>
 
+class CIRCLE;
 class HALF_LINE;
 class LINE;
 class SEG;
 class SHAPE_RECT;
+struct TYPED_POINT2I;
 
 namespace KIGEOM
 {
@@ -118,4 +120,13 @@ SHAPE_ARC MakeArcCw180( const VECTOR2I& aCenter, int aRadius, DIRECTION_45::Dire
  */
 VECTOR2I GetPoint( const SHAPE_RECT& aRect, DIRECTION_45::Directions aDir );
 
+
+/**
+ * Get key points of an CIRCLE.
+ *
+ * - The four cardinal points
+ * - Optionally the center
+ */
+std::vector<TYPED_POINT2I> GetCircleKeyPoints( const CIRCLE& aCircle, bool aIncludeCenter );
+
 } // namespace KIGEOM

libs/kimath/src/geometry/shape_utils.cpp

@@ -23,9 +23,11 @@
 
 #include "geometry/shape_utils.h"
 
+#include <geometry/circle.h>
 #include <geometry/seg.h>
 #include <geometry/half_line.h>
 #include <geometry/line.h>
+#include <geometry/point_types.h>
 #include <geometry/shape_rect.h>
 
 
@@ -251,3 +253,27 @@ VECTOR2I KIGEOM::GetPoint( const SHAPE_RECT& aRect, DIRECTION_45::Directions aDi
     }
     return VECTOR2I();
 }
+
+
+std::vector<TYPED_POINT2I> KIGEOM::GetCircleKeyPoints( const CIRCLE& aCircle, bool aIncludeCenter )
+{
+    std::vector<TYPED_POINT2I> pts;
+
+    if( aIncludeCenter )
+    {
+        pts.emplace_back( VECTOR2I{ 0, 0 }, POINT_TYPE::PT_CENTER );
+    }
+
+    pts.emplace_back( VECTOR2I{ 0, aCircle.Radius }, POINT_TYPE::PT_QUADRANT );
+    pts.emplace_back( VECTOR2I{ aCircle.Radius, 0 }, POINT_TYPE::PT_QUADRANT );
+    pts.emplace_back( VECTOR2I{ 0, -aCircle.Radius }, POINT_TYPE::PT_QUADRANT );
+    pts.emplace_back( VECTOR2I{ -aCircle.Radius, 0 }, POINT_TYPE::PT_QUADRANT );
+
+    // Shift the points to the circle center
+    for( TYPED_POINT2I& pt : pts )
+    {
+        pt.m_point += aCircle.Center;
+    }
+
+    return pts;
+}

pcbnew/pcb_shape.cpp

@@ -37,7 +37,10 @@
 #include <lset.h>
 #include <pad.h>
 #include <base_units.h>
+#include <geometry/shape_circle.h>
 #include <geometry/shape_compound.h>
+#include <geometry/point_types.h>
+#include <geometry/shape_utils.h>
 #include <pcb_shape.h>
 #include <pcb_painter.h>
 #include <api/board/board_types.pb.h>
@@ -336,6 +339,15 @@ std::vector<VECTOR2I> PCB_SHAPE::GetConnectionPoints() const
 
     switch( m_shape )
     {
+    case SHAPE_T::CIRCLE:
+    {
+        const CIRCLE circle( GetCenter(), GetRadius() );
+        for( const TYPED_POINT2I& pt : KIGEOM::GetCircleKeyPoints( circle, false ) )
+        {
+            ret.emplace_back( pt.m_point );
+        }
+        break;
+    }
     case SHAPE_T::ARC:
         ret.emplace_back( GetArcMid() );
         KI_FALLTHROUGH;
@@ -358,7 +370,8 @@ std::vector<VECTOR2I> PCB_SHAPE::GetConnectionPoints() const
 
         break;
 
-    default:
+    case SHAPE_T::UNDEFINED:
+        // No default - handle all cases, even if just break
         break;
     }
 

pcbnew/tools/pcb_grid_helper.cpp

@@ -1057,22 +1057,6 @@ void PCB_GRID_HELPER::computeAnchors( BOARD_ITEM* aItem, const VECTOR2I& aRefPos
             KIGEOM::OVAL_CENTER | KIGEOM::OVAL_CAP_TIPS | KIGEOM::OVAL_SIDE_MIDPOINTS
             | KIGEOM::OVAL_CARDINAL_EXTREMES;
 
-    // The key points of a circle centred around (0, 0) with the given radius
-    auto getCircleKeyPoints = []( int radius, bool aIncludeCenter )
-    {
-        std::vector<TYPED_POINT2I> points = {
-            { { -radius, 0 }, POINT_TYPE::PT_QUADRANT },
-            { { radius, 0 }, POINT_TYPE::PT_QUADRANT },
-            { { 0, -radius }, POINT_TYPE::PT_QUADRANT },
-            { { 0, radius }, POINT_TYPE::PT_QUADRANT },
-        };
-
-        if( aIncludeCenter )
-            points.push_back( { { 0, 0 }, POINT_TYPE::PT_CENTER } );
-
-        return points;
-    };
-
     auto handlePadShape = [&]( PAD* aPad )
     {
         addAnchor( aPad->GetPosition(), ORIGIN | SNAPPABLE, aPad, POINT_TYPE::PT_CENTER );
@@ -1084,14 +1068,15 @@ void PCB_GRID_HELPER::computeAnchors( BOARD_ITEM* aItem, const VECTOR2I& aRefPos
         switch( aPad->GetShape() )
         {
         case PAD_SHAPE::CIRCLE:
-            for( const TYPED_POINT2I& pt : getCircleKeyPoints( aPad->GetSizeX() / 2, false ) )
+        {
+            const CIRCLE circle( aPad->ShapePos(), aPad->GetSizeX() / 2 );
+            for( const TYPED_POINT2I& pt : KIGEOM::GetCircleKeyPoints( circle, false ) )
             {
-                // Transform to the pad positon
-                addAnchor( aPad->ShapePos() + pt.m_point, OUTLINE | SNAPPABLE, aPad, pt.m_types );
+                addAnchor( pt.m_point, OUTLINE | SNAPPABLE, aPad, pt.m_types );
             }
 
             break;
-
+        }
         case PAD_SHAPE::OVAL:
         {
             const OVAL oval( aPad->GetSize(), aPad->GetPosition(), aPad->GetOrientation() );
@@ -1162,7 +1147,8 @@ void PCB_GRID_HELPER::computeAnchors( BOARD_ITEM* aItem, const VECTOR2I& aRefPos
             if( hole_size.x == hole_size.y )
             {
                 // Circle
-                snap_pts = getCircleKeyPoints( hole_size.x / 2, true );
+                const CIRCLE circle( hole_pos, hole_size.x / 2 );
+                snap_pts = KIGEOM::GetCircleKeyPoints( circle, true );
             }
             else
             {
@@ -1171,12 +1157,12 @@ void PCB_GRID_HELPER::computeAnchors( BOARD_ITEM* aItem, const VECTOR2I& aRefPos
                 // For now there's no way to have an off-angle hole, so this is the
                 // same as the pad. In future, this may not be true:
                 // https://gitlab.com/kicad/code/kicad/-/issues/4124
-                const OVAL oval( hole_size, { 0, 0 }, aPad->GetOrientation() );
+                const OVAL oval( hole_size, hole_pos, aPad->GetOrientation() );
                 snap_pts = KIGEOM::GetOvalKeyPoints( oval, ovalKeyPointFlags );
             }
 
             for( const TYPED_POINT2I& snap_pt : snap_pts )
-                addAnchor( hole_pos + snap_pt.m_point, OUTLINE | SNAPPABLE, aPad, snap_pt.m_types );
+                addAnchor( snap_pt.m_point, OUTLINE | SNAPPABLE, aPad, snap_pt.m_types );
         }
     };