From c0f2ac592e406128c9c4945a51e40b50f58bfe56 Mon Sep 17 00:00:00 2001
From: Thomas Krijnen <t.krijnen@gmail.com>
Date: Mon, 22 Jul 2024 13:07:40 +0200
Subject: [PATCH] Consider edge orientation in faceset helper for advanced
 planar breps #4895

---
 src/ifcgeom/kernels/opencascade/faceset_helper.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/ifcgeom/kernels/opencascade/faceset_helper.cpp b/src/ifcgeom/kernels/opencascade/faceset_helper.cpp
index fa7716abe5..3436b67bbd 100644
--- a/src/ifcgeom/kernels/opencascade/faceset_helper.cpp
+++ b/src/ifcgeom/kernels/opencascade/faceset_helper.cpp
@@ -42,7 +42,7 @@ IfcGeom::OpenCascadeKernel::faceset_helper::faceset_helper(
 			loops.push_back(l);
 			for (auto& e : l->children) {
 				// @todo make sure only cartesian points are provided here
-				auto& p = boost::get<ifcopenshell::geometry::taxonomy::point3::ptr>(e->start);
+				auto& p = boost::get<ifcopenshell::geometry::taxonomy::point3::ptr>(e->orientation.get_value_or(true) ? e->start : e->end);
 				if (point_identities_visited.find(p->identity()) == point_identities_visited.end()) {
 					point_identities_visited.insert(p->identity());
 					points.push_back(p);
@@ -201,10 +201,10 @@ void IfcGeom::OpenCascadeKernel::faceset_helper::loop_(const ifcopenshell::geome
 		return;
 	}
 
-	auto a = boost::get<ifcopenshell::geometry::taxonomy::point3::ptr>(ps->children.back()->start);
+	auto a = boost::get<ifcopenshell::geometry::taxonomy::point3::ptr>(ps->children.back()->orientation.get_value_or(true) ? ps->children.back()->start : ps->children.back()->end);
 	auto A = a->identity();
 	for (auto& b : ps->children) {
-		auto B = boost::get<ifcopenshell::geometry::taxonomy::point3::ptr>(b->start)->identity();
+		auto B = boost::get<ifcopenshell::geometry::taxonomy::point3::ptr>(b->orientation.get_value_or(true) ? b->start : b->end)->identity();
 		auto C = vertex_mapping_[A], D = vertex_mapping_[B];
 		bool fwd = C < D;
 		if (!b->orientation) {