From 521efa926dc8f24c2e7e1e85b3689acdcabdc634 Mon Sep 17 00:00:00 2001
From: ika <irina.krylova@opencascade.com>
Date: Fri, 24 Mar 2017 12:24:08 +0300
Subject: [PATCH] 0028589: Data Exchange - Writing face with NaturalRestriction
 flag to IGES

Add additional check for infinite surfaces

Correction of test case for issue CR28589
---
 src/BRepToIGES/BRepToIGES_BRShell.cxx | 9 ++++++++-
 tests/bugs/iges/bug28589              | 8 ++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)
 create mode 100644 tests/bugs/iges/bug28589

diff --git a/src/BRepToIGES/BRepToIGES_BRShell.cxx b/src/BRepToIGES/BRepToIGES_BRShell.cxx
index 9d2003a2bb..235f839365 100644
--- a/src/BRepToIGES/BRepToIGES_BRShell.cxx
+++ b/src/BRepToIGES/BRepToIGES_BRShell.cxx
@@ -26,6 +26,7 @@
 #include <Geom2d_Curve.hxx>
 #include <Geom_ConicalSurface.hxx>
 #include <Geom_CylindricalSurface.hxx>
+#include <Geom_Plane.hxx>
 #include <Geom_RectangularTrimmedSurface.hxx>
 #include <Geom_SphericalSurface.hxx>
 #include <Geom_Surface.hxx>
@@ -313,10 +314,16 @@ Handle(IGESData_IGESEntity) BRepToIGES_BRShell ::TransferFace(const TopoDS_Face&
     }
   }
 
+  // protection against faces on infinite surfaces with mistaken natural restriction flag
+  Standard_Boolean isWholeSurface = BRep_Tool::NaturalRestriction(start);
+  if ((Surf->IsKind(STANDARD_TYPE(Geom_Plane)) ||
+       Surf->IsKind(STANDARD_TYPE(Geom_CylindricalSurface)) ||
+       Surf->IsKind(STANDARD_TYPE(Geom_ConicalSurface))) && !IOuter.IsNull())
+    isWholeSurface = Standard_False;
   // returns the TrimmedSurface
   // --------------------------
   Handle(IGESGeom_TrimmedSurface) TrimmedSurf = new IGESGeom_TrimmedSurface;
-  if (BRep_Tool::NaturalRestriction(start)) {
+  if (isWholeSurface) {
     //if face bounds and surface bounds are same, outer wire is unnecessary
     TrimmedSurf-> Init (ISurf, Standard_False, NULL, Tab);
   }
diff --git a/tests/bugs/iges/bug28589 b/tests/bugs/iges/bug28589
new file mode 100644
index 0000000000..8c1d5cf528
--- /dev/null
+++ b/tests/bugs/iges/bug28589
@@ -0,0 +1,8 @@
+#######################################################################
+# Data Exchange - Writing face with NaturalRestriction flag to IGES
+#######################################################################
+
+restore [locate_data_file bug28589.brep] face
+brepiges face ${imagedir}/${casename}.igs
+igesbrep ${imagedir}/${casename}.igs result *
+checknbshapes result -shape 10