From a3d8ab911fc24d24d85dddaceac5dc6980c324a4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tomasz=20W=C5=82ostowski?= <tomasz.wlostowski@cern.ch>
Date: Tue, 25 Dec 2018 02:29:23 +0100
Subject: [PATCH] router: improved snap-to-clearance zone algorithm in
 highlight collisions mode

---
 pcbnew/router/pns_line_placer.cpp | 29 ++++++++++++++++++++++-------
 1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/pcbnew/router/pns_line_placer.cpp b/pcbnew/router/pns_line_placer.cpp
index a6282085b5..1569ce1394 100644
--- a/pcbnew/router/pns_line_placer.cpp
+++ b/pcbnew/router/pns_line_placer.cpp
@@ -413,24 +413,39 @@ bool LINE_PLACER::rhWalkOnly( const VECTOR2I& aP, LINE& aNewHead )
 
 bool LINE_PLACER::rhMarkObstacles( const VECTOR2I& aP, LINE& aNewHead )
 {
-    buildInitialLine( aP, m_head );
+    LINE newHead( m_head ), bestHead( m_head );
+    bool hasBest = false;
 
-    auto obs = m_currentNode->NearestObstacle( &m_head );
+    buildInitialLine( aP, newHead );
 
-    if( obs )
+    NODE::OBSTACLES obstacles;
+
+    m_currentNode->QueryColliding( &newHead, obstacles );
+
+    for( auto& obs : obstacles )
     {
-        int cl = m_currentNode->GetClearance( obs->m_item, &m_head );
-        auto hull = obs->m_item->Hull( cl, m_head.Width() );
+        int cl = m_currentNode->GetClearance( obs.m_item, &newHead );
+        auto hull = obs.m_item->Hull( cl, newHead.Width() );
 
         auto nearest = hull.NearestPoint( aP );
         Dbg()->AddLine( hull, 2, 10000 );
 
-        if( ( nearest - aP ).EuclideanNorm() < m_head.Width() )
+        if( ( nearest - aP ).EuclideanNorm() < newHead.Width() + cl )
         {
-            buildInitialLine( nearest, m_head );
+            buildInitialLine( nearest, newHead );
+            if ( newHead.CLine().Length() > bestHead.CLine().Length() )
+            {
+                bestHead = newHead;
+                hasBest = true;
+            }
         }
     }
 
+    if( hasBest )
+        m_head = bestHead;
+    else
+        m_head = newHead;
+
     aNewHead = m_head;
 
     return static_cast<bool>( m_currentNode->CheckColliding( &m_head ) );