From 60cf4ab75799d1b6a1d6d34088f7fe085d00b51a Mon Sep 17 00:00:00 2001
From: Thomas Krijnen <t.krijnen@gmail.com>
Date: Tue, 3 May 2016 11:22:15 +0200
Subject: [PATCH] Additional check pertaining to face surfaces

---
 src/ifcgeom/IfcGeomFaces.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/ifcgeom/IfcGeomFaces.cpp b/src/ifcgeom/IfcGeomFaces.cpp
index 9b7b99c2fd..43145528e1 100644
--- a/src/ifcgeom/IfcGeomFaces.cpp
+++ b/src/ifcgeom/IfcGeomFaces.cpp
@@ -224,7 +224,13 @@ bool IfcGeom::Kernel::convert(const IfcSchema::IfcFace* l, TopoDS_Shape& face) {
 				if (mf->IsDone()) {
 					TopoDS_Face outer_face_bound = mf->Face();
 
-					if (BRepCheck_Face(outer_face_bound).OrientationOfWires() == BRepCheck_BadOrientationOfSubshape) {
+					// BRepCheck_Face might raise exceptions in case of face surfaces. Therefore fix orientation regardless.
+					if (!face_surface.IsNull()) {
+						ShapeFix_Face fix(outer_face_bound);
+						fix.FixOrientation();
+						fix.Perform();
+						outer_face_bound = fix.Face();
+					} else if (BRepCheck_Face(outer_face_bound).OrientationOfWires() == BRepCheck_BadOrientationOfSubshape) {
 						wire.Reverse();
 						same_sense = !same_sense;
 						delete mf;