improve trimmed curve handling in both kernels

src/ifcgeom/kernels/cgal/CgalKernel.cpp

@@ -324,6 +324,11 @@ namespace {
 			} else {
 				std::tie(a, b) = param;
 			}
+			a = std::fmod(a, 2 * M_PI);
+			b = std::fmod(b, 2 * M_PI);
+			if (b < a) {
+				b += 2 * M_PI;
+			}
 			int num_segments = (int)std::ceil(std::fabs(a - b) / (2 * M_PI) * FULL_CIRCLE_NUM_SEGMENTS);
 			double du = (b - a) / num_segments;
 			taxonomy::point3 P;
@@ -352,6 +357,10 @@ namespace {
 			boost::apply_visitor(v1, e.start);
 			boost::apply_visitor(v2, e.end);
 
+			if (!e.orientation.get_value_or(true)) {
+				std::swap(v1.u, v2.u);
+			}
+
 			cgal_curve_creation_visitor v({ v1.u, v2.u });
 
 			dispatch_curve_creation<cgal_curve_creation_visitor>::dispatch(e.basis, v);
@@ -392,7 +401,10 @@ bool CgalKernel::convert(const taxonomy::loop* loop, cgal_wire_t& result) {
 	for (auto& e : edges) {
 		if (e->basis) {
 			std::vector<taxonomy::point3> edge;
-			convert_curve(e->basis, points);
+			convert_curve(e, edge);
+			if (!e->orientation_2.get_value_or(true)) {
+				std::reverse(edge.begin(), edge.end());
+			}
 			extend_wire(points, edge);
 		} else {
 			extend_wire(points, {

src/ifcgeom/kernels/opencascade/IfcGeomShapes.cpp

@@ -862,7 +862,7 @@ bool OpenCascadeKernel::convert(const taxonomy::loop* loop, TopoDS_Wire& wire) {
 		std::wcout << o_str.c_str() << std::endl;
 #endif
 
-		if (!segment->orientation) {
+		if (!segment->orientation_2.get_value_or(true)) {
 			segment_wire.Reverse();
 		}
 

src/ifcgeom/schema/mapping.cpp

@@ -1325,7 +1325,7 @@ namespace {
 				*c->matrix.components = Eigen::Affine3d(Eigen::Translation3d(O)).matrix();
 				c->radius = *p.radius;
 				e->basis = c;
-				c->orientation = sign == -1.;
+				c->orientation.reset(sign == -1.);
 
 				loop->children.insert(std::find(loop->children.begin(), loop->children.end(), p.next), e);
 			}
@@ -1612,7 +1612,7 @@ taxonomy::item* mapping::map_impl(const IfcSchema::IfcCompositeCurve* inst) {
 		auto crv = map(segment->ParentCurve());
 		if (crv) {
 			if (crv->kind() == taxonomy::EDGE) {
-				((taxonomy::geom_item*)crv)->orientation = segment->SameSense();
+				((taxonomy::edge*)crv)->orientation_2.reset(segment->SameSense());
 				loop->children.push_back(crv);
 			} else if (crv->kind() == taxonomy::LOOP) {
 				if (!segment->SameSense()) {
@@ -1816,7 +1816,7 @@ taxonomy::item* mapping::map_impl(const IfcSchema::IfcHalfSpaceSolid* inst) {
 	}
 	auto p = new taxonomy::plane;
 	p->matrix = as<taxonomy::matrix4>(map(((IfcSchema::IfcPlane*)surface)->Position()));
-	p->orientation = !inst->AgreementFlag();
+	p->orientation.reset(!inst->AgreementFlag());
 	auto f = new taxonomy::face;
 	f->basis = p;
 	return f;

src/ifcgeom/taxonomy.h

@@ -251,9 +251,11 @@ struct trimmed_curve : public curve {
 
 	// @todo somehow account for the fact that curve in IFC can be trimmed curve, polyline and composite curve as well.
 	item* basis;
-	bool orientation;
 
-	trimmed_curve() : basis(nullptr), orientation(true) {}
+	// @todo does this make sense? this is to accomodate for the fact that orientation is defined on both TrimmedCurve as well CompCurveSegment
+	boost::optional<bool> orientation_2;
+
+	trimmed_curve() : basis(nullptr), orientation_2(true) {}
 	
 	virtual void reverse() {
 		// std::swap(start, end);