Implement mapping of IfcExtrudedAreaSolid

src/ifcgeom/schema/mapping.cpp

@@ -22,9 +22,63 @@
 #include "../../ifcparse/IfcLogger.h"
 
 using namespace IfcUtil;
+using namespace ifcopenshell::geometry;
 
-ifcopenshell::geometry::taxonomy::item* ifcopenshell::geometry::POSTFIX_SCHEMA(mapping)::map(const IfcBaseClass* l) {
+#define mapping POSTFIX_SCHEMA(mapping)
+
+taxonomy::item* mapping::map(const IfcBaseClass* l) {
 #include "bind_convert_impl.i"
 	Logger::Message(Logger::LOG_ERROR, "No operation defined for:", l);
 	return nullptr;
 }
+
+namespace {
+	// A RAII-based mechanism to cast the conversion results
+	// from map() into the right type expected by the higher
+	// level typology items. An exception is thrown if the
+	// types do not match or the result was nullptr. A copy
+	// will be assigned to the higher level topology member
+	// and the original pointer will be deleted.
+
+	// This class is also able to uplift some topology items
+	// to higher level types, such as a loop to a face, which
+	// is why the cast operator does not return a reference.
+	template <typename T>
+	class as {
+	private:
+		taxonomy::item* item_;
+
+	public:
+		as(taxonomy::item* item) : item_(item) {}
+		operator T() const {
+			if (!item_) {
+				throw taxonomy::topology_error;
+			}
+			T* t = dynamic_cast<T*>(item_);
+			if (t) {
+				return *t;
+			} else {
+				if constexpr (std::is_same<T, topology::face>::value) {
+					topology::loop* loop = dynamic_cast<T*>(item_);
+					if (loop) {
+						return topology::face(loop.id, loop.matrix, *loop);
+					}
+				}
+				throw taxonomy::topology_error;
+			}
+		}
+		~as() {
+			delete item;
+		}
+	};
+};
+
+taxonomy::item* mapping::map(const IfcSchema::IfcExtrudedAreaSolid* inst) {
+	return new taxonomy::extrusion(
+		inst->data().id(),
+		as<taxonomy::matrix4>(map(inst->Position())),
+		as<taxonomy::face>(map(inst->SweptArea())),
+		as<taxonomy::direction3>(map(inst->ExtrudedDirection())),
+		inst->Depth()
+	);
+}