From 07085345e90e2452a3ee6c061b59e5bee5fd9bcf Mon Sep 17 00:00:00 2001
From: Jeff Young <jeff@rokeby.ie>
Date: Sat, 1 Aug 2020 21:32:21 +0100
Subject: [PATCH] Flip chamfer corners.

Fixes https://gitlab.com/kicad/code/kicad/issues/5038
---
 pcbnew/class_pad.cpp | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/pcbnew/class_pad.cpp b/pcbnew/class_pad.cpp
index a846d01970..13a4a568e0 100644
--- a/pcbnew/class_pad.cpp
+++ b/pcbnew/class_pad.cpp
@@ -510,6 +510,32 @@ void D_PAD::Flip( const wxPoint& aCentre, bool aFlipLeftRight )
 
     SetOrientation( -GetOrientation() );
 
+    auto mirrorBitFlags = []( int& aBitfield, int a, int b )
+                          {
+                              bool temp = aBitfield & a;
+
+                              if( aBitfield & b )
+                                  aBitfield |= a;
+                              else
+                                  aBitfield &= ~a;
+
+                              if( temp )
+                                  aBitfield |= b;
+                              else
+                                  aBitfield &= ~b;
+                          };
+
+    if( aFlipLeftRight )
+    {
+        mirrorBitFlags( m_chamferPositions, RECT_CHAMFER_TOP_LEFT, RECT_CHAMFER_TOP_RIGHT );
+        mirrorBitFlags( m_chamferPositions, RECT_CHAMFER_BOTTOM_LEFT, RECT_CHAMFER_BOTTOM_RIGHT );
+    }
+    else
+    {
+        mirrorBitFlags( m_chamferPositions, RECT_CHAMFER_TOP_LEFT, RECT_CHAMFER_BOTTOM_LEFT );
+        mirrorBitFlags( m_chamferPositions, RECT_CHAMFER_TOP_RIGHT, RECT_CHAMFER_BOTTOM_RIGHT );
+    }
+
     // flip pads layers
     // PADS items are currently on all copper layers, or
     // currently, only on Front or Back layers.