From 7e1aef22003ab9ffc9831cb320b4ca458587542a Mon Sep 17 00:00:00 2001
From: Marco Mattila <marcom99@gmail.com>
Date: Fri, 16 Aug 2013 14:51:35 +0300
Subject: [PATCH] Pcbnew: fix filleting of zones with parallel adjacent edges

---
 polygon/PolyLine.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/polygon/PolyLine.cpp b/polygon/PolyLine.cpp
index 13c5d08cf9..ee819f8b11 100644
--- a/polygon/PolyLine.cpp
+++ b/polygon/PolyLine.cpp
@@ -448,6 +448,10 @@ CPolyLine* CPolyLine::Fillet( unsigned int aRadius, unsigned int aSegments )
             double          radius  = aRadius;
             double          denom   = sqrt( 2.0 / ( 1 + cosine ) - 1 );
 
+            // Do nothing in case of parallel edges
+            if( isinf( denom ) )
+                continue;
+
             // Limit rounding distance to one half of an edge
             if( 0.5 * lena * denom < radius )
                 radius = 0.5 * lena * denom;