From 88105f891f87886a91c513ab745a853b55b6ccf9 Mon Sep 17 00:00:00 2001
From: jean-pierre charras <jp.charras@wanadoo.fr>
Date: Sun, 16 Apr 2017 18:32:47 +0200
Subject: [PATCH] Fixes Pcbnew bug: Drag Zone Outlines no longer working in
 legacy view

---
 common/geometry/shape_poly_set.cpp | 46 ++++++++++++++++++++++++++----
 include/geometry/shape_poly_set.h  | 18 ++++++------
 pcbnew/class_zone.cpp              | 10 +++++--
 3 files changed, 57 insertions(+), 17 deletions(-)

diff --git a/common/geometry/shape_poly_set.cpp b/common/geometry/shape_poly_set.cpp
index 7313725655..cc3f4aacb2 100644
--- a/common/geometry/shape_poly_set.cpp
+++ b/common/geometry/shape_poly_set.cpp
@@ -325,16 +325,50 @@ const VECTOR2I& SHAPE_POLY_SET::CVertex( SHAPE_POLY_SET::VERTEX_INDEX index ) co
     return CVertex( index.m_vertex, index.m_polygon, index.m_contour - 1 );
 }
 
-
-SEG SHAPE_POLY_SET::Edge( int aGlobalIndex )
+bool SHAPE_POLY_SET::GetNeighbourIndexes( int aGlobalIndex, int* aPrevious, int* aNext )
 {
-    SHAPE_POLY_SET::VERTEX_INDEX indices;
+    SHAPE_POLY_SET::VERTEX_INDEX index;
 
     // If the edge does not exist, throw an exception, it is an illegal access memory error
-    if( !GetRelativeIndices( aGlobalIndex, &indices ) )
-        throw( std::out_of_range( "aGlobalIndex-th edge does not exist" ) );
+    if( !GetRelativeIndices( aGlobalIndex, &index ) )
+        return false;
 
-    return m_polys[indices.m_polygon][indices.m_contour].Segment( indices.m_vertex );
+    // Calculate the previous and next index of aGlobalIndex, corresponding to
+    // the same contour;
+    VERTEX_INDEX inext = index;
+    int lastpoint = m_polys[index.m_polygon][index.m_contour].SegmentCount();
+
+    if( index.m_vertex == 0 )
+    {
+        index.m_vertex = lastpoint;
+        inext.m_vertex = 1;
+    }
+    else if( index.m_vertex == lastpoint )
+    {
+        index.m_vertex--;
+        inext.m_vertex = 0;
+    }
+    else
+    {
+        inext.m_vertex++;
+        index.m_vertex--;
+    }
+
+    if( aPrevious )
+    {
+        int previous;
+        GetGlobalIndex( index, previous );
+        *aPrevious = previous;
+    }
+
+    if( aNext )
+    {
+        int next;
+        GetGlobalIndex( inext, next );
+        *aNext = next;
+    }
+
+    return true;
 }
 
 
diff --git a/include/geometry/shape_poly_set.h b/include/geometry/shape_poly_set.h
index 5e90c61d00..37f7ca5145 100644
--- a/include/geometry/shape_poly_set.h
+++ b/include/geometry/shape_poly_set.h
@@ -392,7 +392,7 @@ class SHAPE_POLY_SET : public SHAPE
          * vertex.
          * @param  aRelativeIndices is the set of relative indices.
          * @param  aGlobalIdx       [out] is the computed global index.
-         * @return bool - true if the relative indices are correct; false otherwise. The cmoputed
+         * @return bool - true if the relative indices are correct; false otherwise. The computed
          *              global index is returned in the \p aGlobalIdx reference.
          */
         bool GetGlobalIndex( VERTEX_INDEX aRelativeIndices, int& aGlobalIdx );
@@ -462,15 +462,17 @@ class SHAPE_POLY_SET : public SHAPE
         const VECTOR2I& CVertex( VERTEX_INDEX aIndex ) const;
 
         /**
-         * Function Edge
-         * Returns a reference to the aGlobalIndex-th segment in the polygon set. Modifying the
-         * points in the returned object will modify the corresponding vertices on the polygon set.
-         * @param  aGlobalIndex is index of the edge, globally indexed between all edges in all
+         * Returns the global indexes of the previous and the next corner
+         * of the aGlobalIndex-th corner of a contour in the polygon set.
+         * they are often aGlobalIndex-1 and aGlobalIndex+1, but not for the first and last
+         * corner of the contour.
+         * @param  aGlobalIndex is index of the corner, globally indexed between all edges in all
          *                      contours
-         * @return SEG - the aGlobalIndex-th segment, whose points are references to the polygon
-         *             points.
+         * @param aPrevious - the globalIndex of the previous corner of the same contour.
+         * @param aNext - the globalIndex of the next corner of the same contour.
+         * @return true if OK, false if aGlobalIndex is out of range
          */
-        SEG Edge( int aGlobalIndex );
+        bool GetNeighbourIndexes( int aGlobalIndex, int* aPrevious, int* aNext );
 
 
         /**
diff --git a/pcbnew/class_zone.cpp b/pcbnew/class_zone.cpp
index 2fab500591..ccaa1db1e9 100644
--- a/pcbnew/class_zone.cpp
+++ b/pcbnew/class_zone.cpp
@@ -729,10 +729,14 @@ void ZONE_CONTAINER::Move( const wxPoint& offset )
 
 void ZONE_CONTAINER::MoveEdge( const wxPoint& offset, int aEdge )
 {
-    m_Poly->Edge( aEdge ).A += VECTOR2I( offset );
-    m_Poly->Edge( aEdge ).B += VECTOR2I( offset );
+    int next_corner;
 
-    Hatch();
+    if( m_Poly->GetNeighbourIndexes( aEdge, nullptr, &next_corner ) )
+    {
+        m_Poly->Vertex( aEdge ) += VECTOR2I( offset );
+        m_Poly->Vertex( next_corner ) += VECTOR2I( offset );
+        Hatch();
+    }
 }