Fixes #3452363 Fail to create meshes of parametric curves when no angular unit information is present in the IFC file

src/ifcgeom/IfcGeomWires.cpp

@@ -80,6 +80,28 @@
 #include "../ifcgeom/IfcGeom.h"
 
 bool IfcGeom::convert(const Ifc2x3::IfcCompositeCurve::ptr l, TopoDS_Wire& wire) {
+	if ( ! Ifc::hasPlaneAngleUnit ) {
+		Ifc::LogMessage("Warning","Creating a composite curve without unit information:",l->entity);
+		Ifc::hasPlaneAngleUnit = true;
+		// First try radians
+		Ifc::PlaneAngleUnit = 1.0f;
+		bool succes_radians = IfcGeom::convert(l,wire);
+		bool succes_degrees;
+		if ( succes_radians ) {
+			Ifc::LogMessage("Notice","Used radians to create composite curve");
+		} else {
+			// Now try degrees
+			Ifc::PlaneAngleUnit = 0.0174532925199433f;
+			succes_degrees = IfcGeom::convert(l,wire);
+			if ( succes_degrees ) {
+				Ifc::LogMessage("Notice","Used degrees to create composite curve");
+			}
+			// Restore to radians
+			Ifc::PlaneAngleUnit = 1.0f;
+		}
+		Ifc::hasPlaneAngleUnit = false;
+		return succes_radians || succes_degrees;
+	}
 	Ifc2x3::IfcCompositeCurveSegment::list segments = l->Segments();
 	BRepBuilderAPI_MakeWire w;
 	//TopoDS_Vertex last_vertex;

src/ifcparse/IfcParse.cpp

@@ -672,6 +672,7 @@ bool Ifc::Init(IfcParse::File* f) {
 				Ifc::LengthUnit = value;
 			} else if ( type == Ifc2x3::IfcUnitEnum::PLANEANGLEUNIT ) {
 				Ifc::PlaneAngleUnit = value;
+				Ifc::hasPlaneAngleUnit = true;
 			}
 		}
 	}
@@ -765,6 +766,7 @@ unsigned int Ifc::lastId = 0;
 Tokens* Ifc::tokens = 0;
 float Ifc::LengthUnit = 1.0f;
 float Ifc::PlaneAngleUnit = 1.0f;
+bool Ifc::hasPlaneAngleUnit = false;
 int Ifc::CircleSegments = 32;
 MapEntitiesByType Ifc::bytype;
 MapEntityById Ifc::byid;

src/ifcparse/IfcParse.h

@@ -247,6 +247,7 @@ public:
 	static bool Init(IfcParse::File* f);
 	static std::string GetLog();
 	static void Dispose();
+	static bool hasPlaneAngleUnit;
 	static float LengthUnit;
 	static float PlaneAngleUnit;
 	static int CircleSegments;