From 0ef63aca4766c93ef86a9c03bea6c93bc49cdbcc Mon Sep 17 00:00:00 2001
From: Jeff Young <jeff@rokeby.ie>
Date: Fri, 11 Dec 2020 17:54:55 +0000
Subject: [PATCH] Don't reset tail when changing track width/via sizes.

Fixes https://gitlab.com/kicad/code/kicad/issues/6314
---
 pcbnew/router/pns_line.h          |  3 +++
 pcbnew/router/pns_line_placer.cpp | 19 ++++++++++++-------
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/pcbnew/router/pns_line.h b/pcbnew/router/pns_line.h
index af98df5e0b..c3170332fb 100644
--- a/pcbnew/router/pns_line.h
+++ b/pcbnew/router/pns_line.h
@@ -238,6 +238,9 @@ public:
 
     const VIA& Via() const { return m_via; }
 
+    void SetViaDiameter( int aDiameter ) { m_via.SetDiameter( aDiameter ); }
+    void SetViaDrill( int aDrill ) { m_via.SetDrill( aDrill ); }
+
     virtual void Mark( int aMarker ) const override;
     virtual void Unmark( int aMarker = -1 ) const override;
     virtual int Marker() const override;
diff --git a/pcbnew/router/pns_line_placer.cpp b/pcbnew/router/pns_line_placer.cpp
index f5f936d460..7692116c65 100644
--- a/pcbnew/router/pns_line_placer.cpp
+++ b/pcbnew/router/pns_line_placer.cpp
@@ -1342,14 +1342,19 @@ void LINE_PLACER::simplifyNewLine( NODE* aNode, SEGMENT* aLatest )
 
 void LINE_PLACER::UpdateSizes( const SIZES_SETTINGS& aSizes )
 {
-    // initPlacement will kill the tail, don't do that unless the track size has changed
-    if( !m_idle && aSizes.TrackWidth() != m_sizes.TrackWidth() )
-    {
-        m_sizes = aSizes;
-        initPlacement();
-    }
-
     m_sizes = aSizes;
+
+    if( !m_idle )
+    {
+        m_head.SetWidth( m_sizes.TrackWidth() );
+        m_tail.SetWidth( m_sizes.TrackWidth() );
+
+        if( m_head.EndsWithVia() )
+        {
+            m_head.SetViaDiameter( m_sizes.ViaDiameter() );
+            m_head.SetViaDrill( m_sizes.ViaDrill() );
+        }
+    }
 }