From 6319b55bc6981ddfad3471476829a26ecb09dac3 Mon Sep 17 00:00:00 2001
From: anv <anv@opencascade.com>
Date: Wed, 28 Jun 2017 16:10:30 +0300
Subject: [PATCH] 0028871: Various problems in SAT export

---
 src/ShapeAnalysis/ShapeAnalysis_Curve.cxx |  2 ++
 tests/bugs/step/bug28871                  | 28 +++++++++++++++++++++++
 2 files changed, 30 insertions(+)
 create mode 100644 tests/bugs/step/bug28871

diff --git a/src/ShapeAnalysis/ShapeAnalysis_Curve.cxx b/src/ShapeAnalysis/ShapeAnalysis_Curve.cxx
index fc6f276894..e33ae0eb04 100644
--- a/src/ShapeAnalysis/ShapeAnalysis_Curve.cxx
+++ b/src/ShapeAnalysis/ShapeAnalysis_Curve.cxx
@@ -737,6 +737,7 @@ Standard_Integer ShapeAnalysis_Curve::SelectForwardSeam(const Handle(Geom2d_Curv
     gp_Pnt2d StartBC1 = BC1->StartPoint();
     gp_Pnt2d EndBC1   = BC1->EndPoint();
     gp_Vec2d VecBC1(StartBC1, EndBC1);
+    if (VecBC1.SquareMagnitude() < gp::Resolution()) return theCurveIndice;
     L1 = new Geom2d_Line(StartBC1, VecBC1);
   }
 
@@ -748,6 +749,7 @@ Standard_Integer ShapeAnalysis_Curve::SelectForwardSeam(const Handle(Geom2d_Curv
     gp_Pnt2d StartBC2 = BC2->StartPoint();
     gp_Pnt2d EndBC2   = BC2->EndPoint();
     gp_Vec2d VecBC2(StartBC2, EndBC2);
+    if (VecBC2.SquareMagnitude() < gp::Resolution()) return theCurveIndice;
     L2 = new Geom2d_Line(StartBC2, VecBC2);
   }
 
diff --git a/tests/bugs/step/bug28871 b/tests/bugs/step/bug28871
new file mode 100644
index 0000000000..938b96dad6
--- /dev/null
+++ b/tests/bugs/step/bug28871
@@ -0,0 +1,28 @@
+puts "========"
+puts "OCC28871"
+puts "========"
+puts ""
+##########################################################################
+# Various problems in SAT export
+##########################################################################
+
+stepread [locate_data_file bug28871_cuffie.stp] a *
+tpcompound result
+
+checkprops result -s 170790 
+checkshape result
+
+set nbshapes_expected "
+Number of shapes in shape
+ VERTEX    : 1387
+ EDGE      : 2222
+ WIRE      : 953
+ FACE      : 928
+ SHELL     : 53
+ SOLID     : 39
+ COMPSOLID : 0
+ COMPOUND  : 1
+ SHAPE     : 5583
+"
+checknbshapes result -ref ${nbshapes_expected} -t -m "importing file"
+checkview -display result -3d -path ${imagedir}/${test_image}.png