From c93109fe434bd3fa4b33f27dc89e8e66c4a57392 Mon Sep 17 00:00:00 2001
From: jgv <jgv@opencascade.com>
Date: Wed, 29 Jul 2015 16:10:53 +0300
Subject: [PATCH] 0026481: Incorrect result of BRepOffsetAPI_MakeOffset: excess
 hanging arcs in the open result with join type GeomAbs_Arc

Test-case for issue #26481
---
 src/BRepFill/BRepFill_OffsetWire.cxx | 18 ++++++++++++++++++
 tests/bugs/modalg_6/bug26481         | 16 ++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 tests/bugs/modalg_6/bug26481

diff --git a/src/BRepFill/BRepFill_OffsetWire.cxx b/src/BRepFill/BRepFill_OffsetWire.cxx
index a3f62ceb00..0cec1a38e2 100644
--- a/src/BRepFill/BRepFill_OffsetWire.cxx
+++ b/src/BRepFill/BRepFill_OffsetWire.cxx
@@ -808,6 +808,24 @@ void BRepFill_OffsetWire::PerformWithBiLo
     }
   }
 
+  //Remove possible hanging arcs on vertices
+  if (myIsOpenResult && myJoinType == GeomAbs_Arc)
+  {
+    if (!myMap.IsEmpty() &&
+        myMap.FindKey(1).ShapeType() == TopAbs_VERTEX)
+    {
+      //myMap.RemoveFirst();
+      TopoDS_Shape LastShape = myMap.FindKey(myMap.Extent());
+      TopTools_ListOfShape LastList;
+      LastList.Append(myMap(myMap.Extent()));
+      myMap.RemoveLast();
+      if (!myMap.IsEmpty())
+        myMap.Substitute(1, LastShape, LastList);
+    }
+    if (!myMap.IsEmpty() &&
+        myMap.FindKey(myMap.Extent()).ShapeType() == TopAbs_VERTEX)
+      myMap.RemoveLast();
+  }
 
 #ifdef OCCT_DEBUG
 #ifdef DRAW
diff --git a/tests/bugs/modalg_6/bug26481 b/tests/bugs/modalg_6/bug26481
new file mode 100644
index 0000000000..36b76c5e40
--- /dev/null
+++ b/tests/bugs/modalg_6/bug26481
@@ -0,0 +1,16 @@
+puts "========"
+puts "OCC26481"
+puts "========"
+puts ""
+###################################################################################################################
+# Incorrect result of BRepOffsetAPI_MakeOffset: excess hanging arcs in the open result with join type GeomAbs_Arc
+###################################################################################################################
+
+smallview
+
+restore [locate_data_file OCC26481-linesarc.brep] a
+fit
+openoffset r a 4 10.
+fit
+
+set only_screen_axo 1