s/MetadataMap/Variables/ etc.

Removed ancient/unused Controller.hpp.


git-svn-id: http://svn.drobilla.net/lad/ingen@852 a436a847-0d15-0410-975c-d299462d15a1

68 files changed, 300 insertions, 387 deletions

diff --git a/src/libs/client/DeprecatedLoader.cpp b/src/libs/client/DeprecatedLoader.cpp
index 22fe1cda..eee9485a 100644
--- a/src/libs/client/DeprecatedLoader.cpp
+++ b/src/libs/client/DeprecatedLoader.cpp
@@ -75,12 +75,12 @@ DeprecatedLoader::translate_load_path(const string& path)
 }
 
 
-/** Add a piece of data to a MetadataMap, translating from deprecated unqualified keys
+/** Add a piece of data to a Variables, translating from deprecated unqualified keys
  *
  * Adds a namespace prefix for known keys, and ignores the rest.
  */
 void
-DeprecatedLoader::add_metadata(GraphObject::MetadataMap& data, string old_key, string value)
+DeprecatedLoader::add_variable(GraphObject::Variables& data, string old_key, string value)
 {
 	string key = "";
 	if (old_key == "module-x")
@@ -132,11 +132,11 @@ DeprecatedLoader::add_metadata(GraphObject::MetadataMap& data, string old_key, s
  * Returns the path of the newly created patch.
  */
 string
-DeprecatedLoader::load_patch(const Glib::ustring&     filename,
-                             boost::optional<Path>    parent_path,
-                             string                   name,
-                             GraphObject::MetadataMap initial_data,
-                             bool                     existing)
+DeprecatedLoader::load_patch(const Glib::ustring&   filename,
+                             boost::optional<Path>  parent_path,
+                             string                 name,
+                             GraphObject::Variables initial_data,
+                             bool                   existing)
 {
 	cerr << "[DeprecatedLoader] Loading patch " << filename << "" << endl;
 
@@ -147,7 +147,7 @@ DeprecatedLoader::load_patch(const Glib::ustring&     filename,
 	size_t poly = 0;
 	
 	/* Use parameter overridden polyphony, if given */
-	GraphObject::MetadataMap::iterator poly_param = initial_data.find("ingen:polyphony");
+	GraphObject::Variables::iterator poly_param = initial_data.find("ingen:polyphony");
 	if (poly_param != initial_data.end() && poly_param->second.type() == Atom::INT)
 		poly = poly_param->second;
 	
@@ -199,10 +199,10 @@ DeprecatedLoader::load_patch(const Glib::ustring&     filename,
 				&& xmlStrcmp(cur->name, (const xmlChar*)"subpatch")
 				&& xmlStrcmp(cur->name, (const xmlChar*)"filename")
 				&& xmlStrcmp(cur->name, (const xmlChar*)"preset")) {
-			// Don't know what this tag is, add it as metadata without overwriting
+			// Don't know what this tag is, add it as variable without overwriting
 			// (so caller can set arbitrary parameters which will be preserved)
 			if (key)
-				add_metadata(initial_data, (const char*)cur->name, (const char*)key);
+				add_variable(initial_data, (const char*)cur->name, (const char*)key);
 		}
 		
 		xmlFree(key);
@@ -217,8 +217,8 @@ DeprecatedLoader::load_patch(const Glib::ustring&     filename,
 	// Create it, if we're not merging
 	if (!existing) {
 		_engine->create_patch(path, poly);
-		for (GraphObject::MetadataMap::const_iterator i = initial_data.begin(); i != initial_data.end(); ++i)
-			_engine->set_metadata(path, i->first, i->second);
+		for (GraphObject::Variables::const_iterator i = initial_data.begin(); i != initial_data.end(); ++i)
+			_engine->set_variable(path, i->first, i->second);
 	}
 
 	// Load nodes
@@ -272,8 +272,8 @@ DeprecatedLoader::load_patch(const Glib::ustring&     filename,
 	xmlCleanupParser();
 
 	// Done above.. late enough?
-	//for (MetadataMap::const_iterator i = data.begin(); i != data.end(); ++i)
-	//	_engine->set_metadata(subject, i->first, i->second);
+	//for (Variables::const_iterator i = data.begin(); i != data.end(); ++i)
+	//	_engine->set_variable(subject, i->first, i->second);
 
 	if (!existing)
 		_engine->enable_patch(path);
@@ -301,7 +301,7 @@ DeprecatedLoader::load_node(const Path& parent, xmlDocPtr doc, const xmlNodePtr
 	string library_name; // deprecated
 	string plugin_label; // deprecated
 
-	GraphObject::MetadataMap initial_data;
+	GraphObject::Variables initial_data;
 
 	while (cur != NULL) {
 		key = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
@@ -355,9 +355,9 @@ DeprecatedLoader::load_node(const Path& parent, xmlDocPtr doc, const xmlNodePtr
 			nm->add_port(pm);
 #endif
 
-		} else {  // Don't know what this tag is, add it as metadata
+		} else {  // Don't know what this tag is, add it as variable
 			if (key)
-				add_metadata(initial_data, (const char*)cur->name, (const char*)key);
+				add_variable(initial_data, (const char*)cur->name, (const char*)key);
 		}
 		xmlFree(key);
 		key = NULL;
@@ -410,8 +410,8 @@ DeprecatedLoader::load_node(const Path& parent, xmlDocPtr doc, const xmlNodePtr
 
 			path = new_path;
 
-			for (GraphObject::MetadataMap::const_iterator i = initial_data.begin(); i != initial_data.end(); ++i)
-				_engine->set_metadata(path, i->first, i->second);
+			for (GraphObject::Variables::const_iterator i = initial_data.begin(); i != initial_data.end(); ++i)
+				_engine->set_variable(path, i->first, i->second);
 
 			return SharedPtr<NodeModel>();
 
@@ -434,8 +434,8 @@ DeprecatedLoader::load_node(const Path& parent, xmlDocPtr doc, const xmlNodePtr
 			else
 				_engine->create_node(path, plugin_type, library_name, plugin_label, polyphonic);
 		
-			for (GraphObject::MetadataMap::const_iterator i = initial_data.begin(); i != initial_data.end(); ++i)
-				_engine->set_metadata(path, i->first, i->second);
+			for (GraphObject::Variables::const_iterator i = initial_data.begin(); i != initial_data.end(); ++i)
+				_engine->set_variable(path, i->first, i->second);
 
 			return true;
 		}
@@ -443,8 +443,8 @@ DeprecatedLoader::load_node(const Path& parent, xmlDocPtr doc, const xmlNodePtr
 	// Not deprecated
 	} else {
 		_engine->create_node(path, plugin_uri, polyphonic);
-		for (GraphObject::MetadataMap::const_iterator i = initial_data.begin(); i != initial_data.end(); ++i)
-			_engine->set_metadata(path, i->first, i->second);
+		for (GraphObject::Variables::const_iterator i = initial_data.begin(); i != initial_data.end(); ++i)
+			_engine->set_variable(path, i->first, i->second);
 		return true;
 	}
 
@@ -462,7 +462,7 @@ DeprecatedLoader::load_subpatch(const Path& parent, xmlDocPtr doc, const xmlNode
 	string filename = "";
 	size_t poly     = 0;
 	
-	GraphObject::MetadataMap initial_data;
+	GraphObject::Variables initial_data;
 
 	while (cur != NULL) {
 		key = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
@@ -473,9 +473,9 @@ DeprecatedLoader::load_subpatch(const Path& parent, xmlDocPtr doc, const xmlNode
 			initial_data.insert(make_pair("ingen::polyphony", (int)poly));
 		} else if ((!xmlStrcmp(cur->name, (const xmlChar*)"filename"))) {
 			filename = (const char*)key;
-		} else {  // Don't know what this tag is, add it as metadata
+		} else {  // Don't know what this tag is, add it as variable
 			if (key != NULL && strlen((const char*)key) > 0)
-				add_metadata(initial_data, (const char*)cur->name, (const char*)key);
+				add_variable(initial_data, (const char*)cur->name, (const char*)key);
 		}
 		xmlFree(key);
 		key = NULL;
@@ -483,7 +483,7 @@ DeprecatedLoader::load_subpatch(const Path& parent, xmlDocPtr doc, const xmlNode
 		cur = cur->next;
 	}
 
-	// load_patch sets the passed metadata last, so values stored in the parent
+	// load_patch sets the passed variable last, so values stored in the parent
 	// will override values stored in the child patch file
 	/*string path = */load_patch(filename, parent, name, initial_data, false);
 	
diff --git a/src/libs/client/DeprecatedLoader.hpp b/src/libs/client/DeprecatedLoader.hpp
index 19dbf5cb..1baf9271 100644
--- a/src/libs/client/DeprecatedLoader.hpp
+++ b/src/libs/client/DeprecatedLoader.hpp
@@ -62,14 +62,14 @@ public:
 	
 	string find_file(const string& filename, const string& additional_path = "");
 	
-	string load_patch(const Glib::ustring&     filename,
-	                  boost::optional<Path>    parent_path,
-	                  string                   name,
-	                  GraphObject::MetadataMap initial_data,
-	                  bool                     existing = false);
+	string load_patch(const Glib::ustring&   filename,
+	                  boost::optional<Path>  parent_path,
+	                  string                 name,
+	                  GraphObject::Variables initial_data,
+	                  bool                   existing = false);
 
 private:
-	void add_metadata(GraphObject::MetadataMap& data, string key, string value);
+	void add_variable(GraphObject::Variables& data, string key, string value);
 
 	string nameify_if_invalid(const string& name);
 	string translate_load_path(const string& path);
diff --git a/src/libs/client/DirectSigClientInterface.hpp b/src/libs/client/DirectSigClientInterface.hpp
index 72265d11..721a7f74 100644
--- a/src/libs/client/DirectSigClientInterface.hpp
+++ b/src/libs/client/DirectSigClientInterface.hpp
@@ -98,8 +98,8 @@ private:
 	virtual void disconnection(const string& src_port_path, const string& dst_port_path)
 	{ disconnection_sig.emit(src_port_path, dst_port_path); }
 	
-	virtual void metadata_update(const string& subject_path, const string& predicate, const string& value)
-	{ metadata_update_sig.emit(subject_path, predicate, value); }
+	virtual void variable_change(const string& subject_path, const string& predicate, const string& value)
+	{ variable_change_sig.emit(subject_path, predicate, value); }
 	
 	virtual void control_change(const string& port_path, float value)
 	{ control_change_sig.emit(port_path, value); }
diff --git a/src/libs/client/NodeModel.cpp b/src/libs/client/NodeModel.cpp
index b8c8e901..1ee67dcf 100644
--- a/src/libs/client/NodeModel.cpp
+++ b/src/libs/client/NodeModel.cpp
@@ -173,8 +173,8 @@ NodeModel::port_value_range(SharedPtr<PortModel> port, float& min, float& max)
 #endif
 
 	// Possibly overriden
-	const Atom& min_atom = port->get_metadata("ingen:minimum");
-	const Atom& max_atom = port->get_metadata("ingen:maximum");
+	const Atom& min_atom = port->get_variable("ingen:minimum");
+	const Atom& max_atom = port->get_variable("ingen:maximum");
 	if (min_atom.type() == Atom::FLOAT)
 		min = min_atom.get_float();
 	if (max_atom.type() == Atom::FLOAT)
diff --git a/src/libs/client/OSCClientReceiver.cpp b/src/libs/client/OSCClientReceiver.cpp
index 0a1fa105..a4197797 100644
--- a/src/libs/client/OSCClientReceiver.cpp
+++ b/src/libs/client/OSCClientReceiver.cpp
@@ -158,7 +158,7 @@ OSCClientReceiver::setup_callbacks()
 	lo_server_thread_add_method(_st, "/ingen/new_port", "ssi", new_port_cb, this);
 	lo_server_thread_add_method(_st, "/ingen/polyphonic", "sT", polyphonic_cb, this);
 	lo_server_thread_add_method(_st, "/ingen/polyphonic", "sF", polyphonic_cb, this);
-	lo_server_thread_add_method(_st, "/ingen/metadata_update", NULL, metadata_update_cb, this);
+	lo_server_thread_add_method(_st, "/ingen/variable_change", NULL, variable_change_cb, this);
 	lo_server_thread_add_method(_st, "/ingen/control_change", "sf", control_change_cb, this);
 	lo_server_thread_add_method(_st, "/ingen/port_activity", "s", port_activity_cb, this);
 	lo_server_thread_add_method(_st, "/ingen/program_add", "siis", program_add_cb, this);
@@ -301,10 +301,10 @@ OSCClientReceiver::_polyphonic_cb(const char* path, const char* types, lo_arg**
 }
 
 
-/** Notification of a new or updated piece of metadata.
+/** Notification of a new or updated piece of variable.
  */
 int
-OSCClientReceiver::_metadata_update_cb(const char* path, const char* types, lo_arg** argv, int argc, lo_message msg)
+OSCClientReceiver::_variable_change_cb(const char* path, const char* types, lo_arg** argv, int argc, lo_message msg)
 {
 	if (argc != 3 || types[0] != 's' || types[1] != 's')
 		return 1;
@@ -314,7 +314,7 @@ OSCClientReceiver::_metadata_update_cb(const char* path, const char* types, lo_a
 
 	Atom value = AtomLiblo::lo_arg_to_atom(types[2], argv[2]);
 
-	metadata_update(obj_path, key, value);
+	variable_change(obj_path, key, value);
 
 	return 0;	
 }
diff --git a/src/libs/client/OSCClientReceiver.hpp b/src/libs/client/OSCClientReceiver.hpp
index 82c4ff4c..8963d3ca 100644
--- a/src/libs/client/OSCClientReceiver.hpp
+++ b/src/libs/client/OSCClientReceiver.hpp
@@ -97,7 +97,7 @@ private:
 	LO_HANDLER(new_node);
 	LO_HANDLER(new_port);
 	LO_HANDLER(polyphonic);
-	LO_HANDLER(metadata_update);
+	LO_HANDLER(variable_change);
 	LO_HANDLER(control_change);
 	LO_HANDLER(port_activity);
 	LO_HANDLER(program_add);
diff --git a/src/libs/client/OSCEngineSender.cpp b/src/libs/client/OSCEngineSender.cpp
index e3183f78..345f4be3 100644
--- a/src/libs/client/OSCEngineSender.cpp
+++ b/src/libs/client/OSCEngineSender.cpp
@@ -494,7 +494,7 @@ OSCEngineSender::midi_learn(const string& node_path)
 
 
 void
-OSCEngineSender::set_metadata(const string&     obj_path,
+OSCEngineSender::set_variable(const string&     obj_path,
                               const string&     predicate,
                               const Raul::Atom& value)
 {
@@ -505,7 +505,7 @@ OSCEngineSender::set_metadata(const string&     obj_path,
 	lo_message_add_string(m, obj_path.c_str());
 	lo_message_add_string(m, predicate.c_str());
 	Raul::AtomLiblo::lo_message_add_atom(m, value);
-	lo_send_message(_engine_addr, "/ingen/set_metadata", m);
+	lo_send_message(_engine_addr, "/ingen/set_variable", m);
 }
 
 
@@ -549,10 +549,10 @@ OSCEngineSender::request_port_value(const string& port_path)
 }
 
 void
-OSCEngineSender::request_metadata(const string& object_path, const string& key)
+OSCEngineSender::request_variable(const string& object_path, const string& key)
 {
 	assert(_engine_addr);
-	lo_send(_engine_addr, "/ingen/request_metadata", "iss",
+	lo_send(_engine_addr, "/ingen/request_variable", "iss",
 		next_id(),
 		object_path.c_str(),
 		key.c_str());
diff --git a/src/libs/client/OSCEngineSender.hpp b/src/libs/client/OSCEngineSender.hpp
index c97c4e94..eb6dd2ee 100644
--- a/src/libs/client/OSCEngineSender.hpp
+++ b/src/libs/client/OSCEngineSender.hpp
@@ -143,7 +143,7 @@ public:
 
 	void midi_learn(const string& node_path);
 
-	void set_metadata(const string&     obj_path,
+	void set_variable(const string&     obj_path,
 	                  const string&     predicate,
 	                  const Raul::Atom& value);
 	
@@ -157,7 +157,7 @@ public:
 
 	void request_port_value(const string& port_path);
 	
-	void request_metadata(const string& path, const string& key);
+	void request_variable(const string& path, const string& key);
 
 	void request_plugins();
 
diff --git a/src/libs/client/ObjectModel.cpp b/src/libs/client/ObjectModel.cpp
index 7d144faf..1d22c8eb 100644
--- a/src/libs/client/ObjectModel.cpp
+++ b/src/libs/client/ObjectModel.cpp
@@ -72,17 +72,17 @@ ObjectModel::find_child(const string& name) const
 }
 
 
-/** Get a piece of metadata for this object.
+/** Get a piece of variable for this object.
  *
  * @return Metadata value with key @a key, empty string otherwise.
  */
 const Atom&
-ObjectModel::get_metadata(const string& key) const
+ObjectModel::get_variable(const string& key) const
 {
 	static const Atom null_atom;
 
-	MetadataMap::const_iterator i = _metadata.find(key);
-	if (i != _metadata.end())
+	Variables::const_iterator i = _variables.find(key);
+	if (i != _variables.end())
 		return i->second;
 	else
 		return null_atom;
@@ -90,11 +90,11 @@ ObjectModel::get_metadata(const string& key) const
 
 
 void
-ObjectModel::add_metadata(const MetadataMap& data)
+ObjectModel::add_variable(const Variables& data)
 {
-	for (MetadataMap::const_iterator i = data.begin(); i != data.end(); ++i) {
-		_metadata[i->first] = i->second;
-		signal_metadata.emit(i->first, i->second);
+	for (Variables::const_iterator i = data.begin(); i != data.end(); ++i) {
+		_variables[i->first] = i->second;
+		signal_variable.emit(i->first, i->second);
 	}
 }
 
@@ -117,18 +117,18 @@ ObjectModel::set(SharedPtr<ObjectModel> model)
 {
 	assert(_path == model->path());
 
-	for (MetadataMap::const_iterator other = model->metadata().begin();
-			other != model->metadata().end(); ++other) {
+	for (Variables::const_iterator other = model->variables().begin();
+			other != model->variables().end(); ++other) {
 		
-		MetadataMap::const_iterator mine = _metadata.find(other->first);
+		Variables::const_iterator mine = _variables.find(other->first);
 		
-		if (mine != _metadata.end()) {
+		if (mine != _variables.end()) {
 			cerr << "WARNING:  " << _path << "Client/Server data mismatch: " << other->first << endl;
 			cerr << "Setting server value " << other->second;
 		}
 
-		_metadata[other->first] = other->second;
-		signal_metadata.emit(other->first, other->second);
+		_variables[other->first] = other->second;
+		signal_variable.emit(other->first, other->second);
 	}
 }
 
diff --git a/src/libs/client/ObjectModel.hpp b/src/libs/client/ObjectModel.hpp
index 3c13b227..f9be4fa6 100644
--- a/src/libs/client/ObjectModel.hpp
+++ b/src/libs/client/ObjectModel.hpp
@@ -59,11 +59,11 @@ class ObjectModel : virtual public Ingen::Shared::GraphObject, public boost::non
 public:
 	virtual ~ObjectModel();
 
-	const Atom& get_metadata(const string& key) const;
-	void set_metadata(const string& key, const Atom& value)
-		{ _metadata.insert(make_pair(key, value)); signal_metadata.emit(key, value); }
+	const Atom& get_variable(const string& key) const;
+	void set_variable(const string& key, const Atom& value)
+		{ _variables.insert(make_pair(key, value)); signal_variable.emit(key, value); }
 
-	const MetadataMap&     metadata()   const { return _metadata; }
+	const Variables&       variables()  const { return _variables; }
 	const Path             path()       const { return _path; }
 	const string           name()       const { return _path.name(); }
 	SharedPtr<ObjectModel> parent()     const { return _parent; }
@@ -76,7 +76,7 @@ public:
 	// Signals
 	sigc::signal<void, SharedPtr<ObjectModel> >    signal_new_child; 
 	sigc::signal<void, SharedPtr<ObjectModel> >    signal_removed_child; 
-	sigc::signal<void, const string&, const Atom&> signal_metadata; 
+	sigc::signal<void, const string&, const Atom&> signal_variable; 
 	sigc::signal<void, bool>                       signal_polyphonic; 
 	sigc::signal<void>                             signal_destroyed; 
 	sigc::signal<void>                             signal_renamed; 
@@ -91,7 +91,7 @@ protected:
 	virtual void add_child(SharedPtr<ObjectModel> c) {}
 	virtual bool remove_child(SharedPtr<ObjectModel> c) { return true; }
 
-	void add_metadata(const MetadataMap& data);
+	void add_variable(const Variables& data);
 	void set_polyphonic(bool);
 	
 	void set(SharedPtr<ObjectModel> model);
@@ -101,7 +101,7 @@ protected:
 	bool                   _polyphonic;
 	SharedPtr<ObjectModel> _parent;
 	
-	MetadataMap _metadata;
+	Variables _variables;
 };
 
 
diff --git a/src/libs/client/PortModel.cpp b/src/libs/client/PortModel.cpp
index ed59c8ca..6b727747 100644
--- a/src/libs/client/PortModel.cpp
+++ b/src/libs/client/PortModel.cpp
@@ -25,7 +25,7 @@ namespace Client {
 bool
 PortModel::is_logarithmic() const
 {
-	const Atom& hint = get_metadata("ingen:logarithmic");
+	const Atom& hint = get_variable("ingen:logarithmic");
 	return (hint && hint > 0);
 }
 
@@ -33,7 +33,7 @@ PortModel::is_logarithmic() const
 bool
 PortModel::is_integer() const
 {
-	const Atom& hint = get_metadata("ingen:integer");
+	const Atom& hint = get_variable("ingen:integer");
 	return (hint && hint > 0);
 }
 
@@ -41,7 +41,7 @@ PortModel::is_integer() const
 bool
 PortModel::is_toggle() const
 {
-	const Atom& hint = get_metadata("ingen:toggled");
+	const Atom& hint = get_variable("ingen:toggled");
 	return (hint && hint > 0);
 }
 
diff --git a/src/libs/client/SigClientInterface.hpp b/src/libs/client/SigClientInterface.hpp
index 895b4cde..27469f9e 100644
--- a/src/libs/client/SigClientInterface.hpp
+++ b/src/libs/client/SigClientInterface.hpp
@@ -62,7 +62,7 @@ public:
 	sigc::signal<void, string>                             signal_object_destroyed; 
 	sigc::signal<void, string, string>                     signal_connection; 
 	sigc::signal<void, string, string>                     signal_disconnection; 
-	sigc::signal<void, string, string, Raul::Atom>         signal_metadata_update; 
+	sigc::signal<void, string, string, Raul::Atom>         signal_variable_change; 
 	sigc::signal<void, string, float>                      signal_control_change; 
 	sigc::signal<void, string>                             signal_port_activity; 
 	sigc::signal<void, string, uint32_t, uint32_t, string> signal_program_add; 
@@ -129,8 +129,8 @@ protected:
 	void disconnection(const string& src_port_path, const string& dst_port_path)
 		{ signal_disconnection.emit(src_port_path, dst_port_path); }
 	
-	void metadata_update(const string& path, const string& key, const Raul::Atom& value)
-		{ signal_metadata_update.emit(path, key, value); }
+	void variable_change(const string& path, const string& key, const Raul::Atom& value)
+		{ signal_variable_change.emit(path, key, value); }
 
 	void control_change(const string& port_path, float value)
 		{ signal_control_change.emit(port_path, value); }
diff --git a/src/libs/client/Store.cpp b/src/libs/client/Store.cpp
index ae07fa08..ab2ea280 100644
--- a/src/libs/client/Store.cpp
+++ b/src/libs/client/Store.cpp
@@ -49,7 +49,7 @@ Store::Store(SharedPtr<EngineInterface> engine, SharedPtr<SigClientInterface> em
 	emitter->signal_patch_cleared.connect(sigc::mem_fun(this, &Store::patch_cleared_event));
 	emitter->signal_connection.connect(sigc::mem_fun(this, &Store::connection_event));
 	emitter->signal_disconnection.connect(sigc::mem_fun(this, &Store::disconnection_event));
-	emitter->signal_metadata_update.connect(sigc::mem_fun(this, &Store::metadata_update_event));
+	emitter->signal_variable_change.connect(sigc::mem_fun(this, &Store::variable_change_event));
 	emitter->signal_control_change.connect(sigc::mem_fun(this, &Store::control_change_event));
 	emitter->signal_port_activity.connect(sigc::mem_fun(this, &Store::port_activity_event));
 }
@@ -158,38 +158,38 @@ Store::add_orphan(SharedPtr<ObjectModel> child)
 
 
 void
-Store::add_metadata_orphan(const Path& subject_path, const string& predicate, const Atom& value)
+Store::add_variable_orphan(const Path& subject_path, const string& predicate, const Atom& value)
 {
 	Raul::PathTable<list<std::pair<string, Atom> > >::iterator orphans
-		= _metadata_orphans.find(subject_path);
+		= _variable_orphans.find(subject_path);
 
 	_engine->request_object(subject_path);
 
-	if (orphans != _metadata_orphans.end()) {
+	if (orphans != _variable_orphans.end()) {
 		orphans->second.push_back(std::pair<string, Atom>(predicate, value));
 	} else {
 		list<std::pair<string, Atom> > l;
 		l.push_back(std::pair<string, Atom>(predicate, value));
-		_metadata_orphans[subject_path] = l;
+		_variable_orphans[subject_path] = l;
 	}
 }
 
 
 void
-Store::resolve_metadata_orphans(SharedPtr<ObjectModel> subject)
+Store::resolve_variable_orphans(SharedPtr<ObjectModel> subject)
 {
 	Raul::PathTable<list<std::pair<string, Atom> > >::iterator v
-		= _metadata_orphans.find(subject->path());
+		= _variable_orphans.find(subject->path());
 
-	if (v != _metadata_orphans.end()) {
+	if (v != _variable_orphans.end()) {
 	
 		list<std::pair<string, Atom> > values = v->second; // take a copy
 
-		_metadata_orphans.erase(subject->path());
+		_variable_orphans.erase(subject->path());
 		
 		for (list<std::pair<string, Atom> >::iterator i = values.begin();
 				i != values.end(); ++i) {
-			subject->set_metadata(i->first, i->second);
+			subject->set_variable(i->first, i->second);
 		}
 	}
 }
@@ -236,7 +236,7 @@ Store::add_object(SharedPtr<ObjectModel> object)
 				_objects[object->path()] = object;
 				signal_new_object.emit(object);
 				
-				resolve_metadata_orphans(parent);
+				resolve_variable_orphans(parent);
 				resolve_orphans(parent);
 
 				SharedPtr<PortModel> port = PtrCast<PortModel>(object);
@@ -487,15 +487,15 @@ Store::patch_cleared_event(const Path& path)
 
 
 void
-Store::metadata_update_event(const Path& subject_path, const string& predicate, const Atom& value)
+Store::variable_change_event(const Path& subject_path, const string& predicate, const Atom& value)
 {
 	SharedPtr<ObjectModel> subject = object(subject_path);
 	
 	if (subject) {
-		subject->set_metadata(predicate, value);
+		subject->set_variable(predicate, value);
 	} else {
-		add_metadata_orphan(subject_path, predicate, value);
-		cerr << "WARNING: metadata for unknown object " << subject_path << endl;
+		add_variable_orphan(subject_path, predicate, value);
+		cerr << "WARNING: variable for unknown object " << subject_path << endl;
 	}
 }
 
diff --git a/src/libs/client/Store.hpp b/src/libs/client/Store.hpp
index dad403d0..2849afc3 100644
--- a/src/libs/client/Store.hpp
+++ b/src/libs/client/Store.hpp
@@ -91,8 +91,8 @@ private:
 	void add_plugin_orphan(SharedPtr<NodeModel> orphan);
 	void resolve_plugin_orphans(SharedPtr<PluginModel> plugin);
 	
-	void add_metadata_orphan(const Path& subject, const string& predicate, const Atom& value);
-	void resolve_metadata_orphans(SharedPtr<ObjectModel> subject);
+	void add_variable_orphan(const Path& subject, const string& predicate, const Atom& value);
+	void resolve_variable_orphans(SharedPtr<ObjectModel> subject);
 
 	// Slots for SigClientInterface signals
 	void destruction_event(const Path& path);
@@ -106,7 +106,7 @@ private:
 	void patch_disabled_event(const Path& path);
 	void patch_polyphony_event(const Path& path, uint32_t poly);
 	void patch_cleared_event(const Path& path);
-	void metadata_update_event(const Path& subject_path, const string& predicate, const Atom& value);
+	void variable_change_event(const Path& subject_path, const string& predicate, const Atom& value);
 	void control_change_event(const Path& port_path, float value);
 	void port_activity_event(const Path& port_path);
 	void connection_event(const Path& src_port_path, const Path& dst_port_path);
@@ -128,8 +128,8 @@ private:
 	 * It's unfortunate everything doesn't just have a URI and this was the same.. ahem.. */
 	Raul::Table<string, list<SharedPtr<NodeModel> > > _plugin_orphans;
 	
-	/** Not orphans OF metadata like the above, but orphans which are metadata */
-	Raul::PathTable<list<std::pair<string, Atom> > > _metadata_orphans;
+	/** Not orphans OF variable like the above, but orphans which are variable */
+	Raul::PathTable<list<std::pair<string, Atom> > > _variable_orphans;
 	
 	/** Ditto */
 	list<std::pair<Path, Path> > _connection_orphans;
diff --git a/src/libs/client/ThreadedSigClientInterface.hpp b/src/libs/client/ThreadedSigClientInterface.hpp
index c79ed090..8a4db3f7 100644
--- a/src/libs/client/ThreadedSigClientInterface.hpp
+++ b/src/libs/client/ThreadedSigClientInterface.hpp
@@ -63,7 +63,7 @@ public:
 	, object_destroyed_slot(signal_object_destroyed.make_slot())
 	, object_renamed_slot(signal_object_renamed.make_slot())
 	, disconnection_slot(signal_disconnection.make_slot())
-	, metadata_update_slot(signal_metadata_update.make_slot())
+	, variable_change_slot(signal_variable_change.make_slot())
 	, control_change_slot(signal_control_change.make_slot())
 	, port_activity_slot(signal_port_activity.make_slot())
 	, program_add_slot(signal_program_add.make_slot())
@@ -133,8 +133,8 @@ public:
 	void disconnection(const string& src_port_path, const string& dst_port_path)
 		{ push_sig(sigc::bind(disconnection_slot, src_port_path, dst_port_path)); }
 	
-	void metadata_update(const string& path, const string& key, const Raul::Atom& value)
-		{ push_sig(sigc::bind(metadata_update_slot, path, key, value)); }
+	void variable_change(const string& path, const string& key, const Raul::Atom& value)
+		{ push_sig(sigc::bind(variable_change_slot, path, key, value)); }
 
 	void control_change(const string& port_path, float value)
 		{ push_sig(sigc::bind(control_change_slot, port_path, value)); }
@@ -178,7 +178,7 @@ private:
 	sigc::slot<void, string>                             object_destroyed_slot; 
 	sigc::slot<void, string, string>                     object_renamed_slot; 
 	sigc::slot<void, string, string>                     disconnection_slot; 
-	sigc::slot<void, string, string, Raul::Atom>         metadata_update_slot; 
+	sigc::slot<void, string, string, Raul::Atom>         variable_change_slot; 
 	sigc::slot<void, string, float>                      control_change_slot; 
 	sigc::slot<void, string>                             port_activity_slot; 
 	sigc::slot<void, string, uint32_t, uint32_t, string> program_add_slot; 
diff --git a/src/libs/engine/ClientBroadcaster.cpp b/src/libs/engine/ClientBroadcaster.cpp
index 2360dd09..df8e6c6f 100644
--- a/src/libs/engine/ClientBroadcaster.cpp
+++ b/src/libs/engine/ClientBroadcaster.cpp
@@ -201,15 +201,15 @@ ClientBroadcaster::send_patch_polyphony(const string& patch_path, uint32_t poly)
 }
 
 
-/** Send notification of a metadata update.
+/** Send notification of a variable update.
  *
- * Like control changes, does not send update to client that set the metadata, if applicable.
+ * Like control changes, does not send update to client that set the variable, if applicable.
  */
 void
-ClientBroadcaster::send_metadata_update(const string& node_path, const string& key, const Atom& value)
+ClientBroadcaster::send_variable_change(const string& node_path, const string& key, const Atom& value)
 {
 	for (Clients::const_iterator i = _clients.begin(); i != _clients.end(); ++i)
-		(*i).second->metadata_update(node_path, key, value);
+		(*i).second->variable_change(node_path, key, value);
 }
 
 
diff --git a/src/libs/engine/ClientBroadcaster.hpp b/src/libs/engine/ClientBroadcaster.hpp
index d7621555..ecd19d34 100644
--- a/src/libs/engine/ClientBroadcaster.hpp
+++ b/src/libs/engine/ClientBroadcaster.hpp
@@ -75,7 +75,7 @@ public:
 	void send_patch_enable(const string& patch_path);
 	void send_patch_disable(const string& patch_path);
 	void send_patch_polyphony(const string& patch_path, uint32_t poly);
-	void send_metadata_update(const string& node_path, const string& key, const Raul::Atom& value);
+	void send_variable_change(const string& node_path, const string& key, const Raul::Atom& value);
 	void send_control_change(const string& port_path, float value);
 	void send_port_activity(const string& port_path);
 	void send_program_add(const string& node_path, int bank, int program, const string& name);
diff --git a/src/libs/engine/Controller.hpp b/src/libs/engine/Controller.hpp
deleted file mode 100644
index 95f7cc44..00000000
--- a/src/libs/engine/Controller.hpp
+++ /dev/null
@@ -1,83 +0,0 @@
-/* This file is part of Ingen.
- * Copyright (C) 2007 Dave Robillard <http://drobilla.net>
- * 
- * Ingen is free software; you can redistribute it and/or modify it under the
- * terms of the GNU General Public License as published by the Free Software
- * Foundation; either version 2 of the License, or (at your option) any later
- * version.
- * 
- * Ingen is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
- * 
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef CONTROLLER_H
-#define CONTROLLER_H
-
-namespace Ingen {
-
-
-/** Public interface to engine library.
- *
- * This is an interface to all the audio-processing related functionality
- * only.  OSC communication, LASH session management, etc, are not part of 
- * this library.
- */
-class Controller {
-public:
-	void init();
-	void quit();
-	
-	void load_plugins();
-	
-	void activate_engine();
-	void deactivate_engine();
-	
-	void create_patch(const char* path, unsigned int polyphony);
-	void clear_patch(const char* path);
-	void enable_patch(const char* path);
-	void disable_patch(const char* path);
-	void rename(const char* old_path, const char* new_path);
-	
-	void create_node(const char*  path,
-	                 const char*  type,
-					 const char*  library_name,
-					 const char*  library_label,
-					 unsigned int polyphony);
-	
-	void destroy(const char* path);
-	
-	void connect(const char* src_port_path, const char* dst_port_path);
-	void disconnect(const char* src_port_path, const char* dst_port_path);
-	void disconnect_all(const char* path);
-	
-	void set_port_value(const char* path, float value);
-	void set_port_value_voice(const char* path, unsigned int voice);
-	void set_port_value_slow(const char* path, float value);
-	
-	void note_on(const char*   node_path,
-	             unsigned char note_num,
-	       	     unsigned char velocity);
-	
-	void note_off(const char*   node_path,
-	             unsigned char  note_num);
-	
-	void all_notes_off(const char* node_path);
-	void midi_learn(const char* node_path);
-	
-	void get_metadata();
-	void set_metadata();
-	void responder_plugins();
-	void responder_all_objects();
-	void responder_port_value();
-};
-
-
-} // namespace Ingen
-
-#endif // CONTROLLER_H
-
diff --git a/src/libs/engine/GraphObjectImpl.hpp b/src/libs/engine/GraphObjectImpl.hpp
index 1793366e..3862c762 100644
--- a/src/libs/engine/GraphObjectImpl.hpp
+++ b/src/libs/engine/GraphObjectImpl.hpp
@@ -42,7 +42,7 @@ class ProcessContext;
 /** An object on the audio graph - Patch, Node, Port, etc.
  *
  * Each of these is a Raul::Deletable and so can be deleted in a realtime safe
- * way from anywhere, and they all have a map of metadata for clients to store
+ * way from anywhere, and they all have a map of variable for clients to store
  * arbitrary values in (which the engine puts no significance to whatsoever).
  *
  * \ingroup engine
@@ -67,16 +67,16 @@ public:
 		assert(_name.find("/") == string::npos);
 	}
 	
-	void set_metadata(const string& key, const Atom& value)
-	{ _metadata[key] = value; }
+	void set_variable(const string& key, const Atom& value)
+		{ _variables[key] = value; }
 
-	const Atom& get_metadata(const string& key) {
+	const Atom& get_variable(const string& key) {
 		static Atom null_atom;
-		MetadataMap::iterator i = _metadata.find(key);
-		return (i != _metadata.end()) ? (*i).second : null_atom;
+		Variables::iterator i = _variables.find(key);
+		return (i != _variables.end()) ? (*i).second : null_atom;
 	}
 
-	const MetadataMap& metadata() const { return _metadata; }
+	const Variables& variables() const { return _variables; }
 
 	/** The Patch this object is a child of. */
 	virtual PatchImpl* parent_patch() const;
@@ -109,7 +109,7 @@ protected:
 	bool             _polyphonic;
 
 private:	
-	MetadataMap _metadata;
+	Variables _variables;
 };
 
 
diff --git a/src/libs/engine/LADSPANode.cpp b/src/libs/engine/LADSPANode.cpp
index ce61eb5d..5ae567db 100644
--- a/src/libs/engine/LADSPANode.cpp
+++ b/src/libs/engine/LADSPANode.cpp
@@ -145,8 +145,8 @@ LADSPANode::instantiate()
 		}
 
 		if (port->is_input() && port->buffer_size() == 1) {
-			port->set_metadata("ingen:minimum", min);
-			port->set_metadata("ingen:maximum", max);
+			port->set_variable("ingen:minimum", min);
+			port->set_variable("ingen:maximum", max);
 		}
 	}
 
diff --git a/src/libs/engine/MidiControlNode.cpp b/src/libs/engine/MidiControlNode.cpp
index 27047263..250607b0 100644
--- a/src/libs/engine/MidiControlNode.cpp
+++ b/src/libs/engine/MidiControlNode.cpp
@@ -40,19 +40,19 @@ MidiControlNode::MidiControlNode(const string& path, bool polyphonic, PatchImpl*
 	_ports->at(0) = _midi_in_port;
 	
 	_param_port = new InputPort(this, "ControllerNumber", 1, 1, DataType::CONTROL, 1);
-	_param_port->set_metadata("ingen:minimum", 0.0f);
-	_param_port->set_metadata("ingen:maximum", 127.0f);
-	_param_port->set_metadata("ingen:default", 0.0f);
-	_param_port->set_metadata("ingen:integer", 1);
+	_param_port->set_variable("ingen:minimum", 0.0f);
+	_param_port->set_variable("ingen:maximum", 127.0f);
+	_param_port->set_variable("ingen:default", 0.0f);
+	_param_port->set_variable("ingen:integer", 1);
 	_ports->at(1) = _param_port;
 
 	_log_port = new InputPort(this, "Logarithmic", 2, 1, DataType::CONTROL, 1);
-	_log_port->set_metadata("ingen:toggled", 1);
-	_log_port->set_metadata("ingen:default", 0.0f);
+	_log_port->set_variable("ingen:toggled", 1);
+	_log_port->set_variable("ingen:default", 0.0f);
 	_ports->at(2) = _log_port;
 	
 	_min_port = new InputPort(this, "Min", 3, 1, DataType::CONTROL, 1);
-	_min_port->set_metadata("ingen:default", 0.0f);
+	_min_port->set_variable("ingen:default", 0.0f);
 	_ports->at(3) = _min_port;
 	
 	_max_port = new InputPort(this, "Max", 4, 1, DataType::CONTROL, 1);
diff --git a/src/libs/engine/MidiNoteNode.cpp b/src/libs/engine/MidiNoteNode.cpp
index 7337ade5..7604bc61 100644
--- a/src/libs/engine/MidiNoteNode.cpp
+++ b/src/libs/engine/MidiNoteNode.cpp
@@ -53,18 +53,18 @@ MidiNoteNode::MidiNoteNode(const string& path, bool polyphonic, PatchImpl* paren
 	_ports->at(1) = _freq_port;
 	
 	_vel_port = new OutputPort(this, "Velocity", 2, _polyphony, DataType::AUDIO, _buffer_size);
-	_vel_port->set_metadata("ingen:minimum", 0.0f);
-	_vel_port->set_metadata("ingen:maximum", 1.0f);
+	_vel_port->set_variable("ingen:minimum", 0.0f);
+	_vel_port->set_variable("ingen:maximum", 1.0f);
 	_ports->at(2) = _vel_port;
 	
 	_gate_port = new OutputPort(this, "Gate", 3, _polyphony, DataType::AUDIO, _buffer_size);
-	_gate_port->set_metadata("ingen:toggled", 1);
-	_gate_port->set_metadata("ingen:default", 0.0f);
+	_gate_port->set_variable("ingen:toggled", 1);
+	_gate_port->set_variable("ingen:default", 0.0f);
 	_ports->at(3) = _gate_port;
 	
 	_trig_port = new OutputPort(this, "Trigger", 4, _polyphony, DataType::AUDIO, _buffer_size);
-	_trig_port->set_metadata("ingen:toggled", 1);
-	_trig_port->set_metadata("ingen:default", 0.0f);
+	_trig_port->set_variable("ingen:toggled", 1);
+	_trig_port->set_variable("ingen:default", 0.0f);
 	_ports->at(4) = _trig_port;
 	
 	PluginImpl* p = const_cast<PluginImpl*>(_plugin);
diff --git a/src/libs/engine/MidiTriggerNode.cpp b/src/libs/engine/MidiTriggerNode.cpp
index f5009a80..f179d7b0 100644
--- a/src/libs/engine/MidiTriggerNode.cpp
+++ b/src/libs/engine/MidiTriggerNode.cpp
@@ -37,10 +37,10 @@ MidiTriggerNode::MidiTriggerNode(const string& path, bool polyphonic, PatchImpl*
 	_ports->at(0) = _midi_in_port;
 	
 	_note_port = new InputPort(this, "NoteNumber", 1, 1, DataType::CONTROL, 1);
-	_note_port->set_metadata("ingen:minimum", 0.0f);
-	_note_port->set_metadata("ingen:maximum", 127.0f);
-	_note_port->set_metadata("ingen:default", 60.0f);
-	_note_port->set_metadata("ingen:integer", 1);
+	_note_port->set_variable("ingen:minimum", 0.0f);
+	_note_port->set_variable("ingen:maximum", 127.0f);
+	_note_port->set_variable("ingen:default", 60.0f);
+	_note_port->set_variable("ingen:integer", 1);
 	_ports->at(1) = _note_port;
 	
 	_gate_port = new OutputPort(this, "Gate", 2, 1, DataType::AUDIO, _buffer_size);
diff --git a/src/libs/engine/OSCClientSender.cpp b/src/libs/engine/OSCClientSender.cpp
index 45c0e804..fff564d6 100644
--- a/src/libs/engine/OSCClientSender.cpp
+++ b/src/libs/engine/OSCClientSender.cpp
@@ -280,7 +280,7 @@ void OSCClientSender::new_node(const std::string&   plugin_uri,
  * \li The minimum and maximum values are suggestions only, they are not
  * enforced in any way, and going outside them is perfectly fine.  Also note
  * that the port ranges in om_gtk are not these ones!  Those ranges are set
- * as metadata.</p> \n \n
+ * as variable.</p> \n \n
  */
 void
 OSCClientSender::new_port(const std::string& path,
@@ -422,13 +422,13 @@ OSCClientSender::disconnection(const std::string& src_port_path, const std::stri
 
 
 /** \page client_osc_namespace
- * <p> \b /ingen/metadata_update - Notification of a piece of metadata.
- * \arg \b path (string) - Path of the object associated with metadata (can be a node, patch, or port)
+ * <p> \b /ingen/variable_change - Notification of a piece of variable.
+ * \arg \b path (string) - Path of the object associated with variable (can be a node, patch, or port)
  * \arg \b key (string)
  * \arg \b value (string)</p> \n \n
  */
 void
-OSCClientSender::metadata_update(const std::string& path, const std::string& key, const Atom& value)
+OSCClientSender::variable_change(const std::string& path, const std::string& key, const Atom& value)
 {
 	if (!_enabled)
 		return;
@@ -437,7 +437,7 @@ OSCClientSender::metadata_update(const std::string& path, const std::string& key
 	lo_message_add_string(m, path.c_str());
 	lo_message_add_string(m, key.c_str());
 	Raul::AtomLiblo::lo_message_add_atom(m, value);
-	lo_send_message(_address, "/ingen/metadata_update", m);
+	lo_send_message(_address, "/ingen/variable_change", m);
 }
 
 
@@ -523,10 +523,10 @@ OSCClientSender::new_patch(const std::string& path, uint32_t poly)
 	if (p->process())
 		patch_enabled(p->path());
 	
-	// Send metadata
-	const map<const std::string&, const std::string&>& data = p->metadata();
+	// Send variables
+	const map<const std::string&, const std::string&>& data = p->variable();
 	for (map<const std::string&, const std::string&>::const_iterator i = data.begin(); i != data.end(); ++i) {
-		metadata_update(p->path(), (*i).first, (*i).second);
+		variable_change(p->path(), (*i).first, (*i).second);
 	}
 	*/
 }
diff --git a/src/libs/engine/OSCClientSender.hpp b/src/libs/engine/OSCClientSender.hpp
index 0d46545b..5388140d 100644
--- a/src/libs/engine/OSCClientSender.hpp
+++ b/src/libs/engine/OSCClientSender.hpp
@@ -113,7 +113,7 @@ public:
 	virtual void disconnection(const std::string& src_port_path,
 	                           const std::string& dst_port_path);
 	
-	virtual void metadata_update(const std::string& subject_path,
+	virtual void variable_change(const std::string& subject_path,
 	                             const std::string& predicate,
 	                             const Raul::Atom&  value);
 	
diff --git a/src/libs/engine/OSCEngineReceiver.cpp b/src/libs/engine/OSCEngineReceiver.cpp
index cfb3f860..7d05e0bb 100644
--- a/src/libs/engine/OSCEngineReceiver.cpp
+++ b/src/libs/engine/OSCEngineReceiver.cpp
@@ -106,10 +106,10 @@ OSCEngineReceiver::OSCEngineReceiver(Engine& engine, size_t queue_size, uint16_t
 	lo_server_add_method(_server, "/ingen/note_off", "isi", note_off_cb, this);
 	lo_server_add_method(_server, "/ingen/all_notes_off", "isi", all_notes_off_cb, this);
 	lo_server_add_method(_server, "/ingen/midi_learn", "is", midi_learn_cb, this);
-	lo_server_add_method(_server, "/ingen/set_metadata", NULL, metadata_set_cb, this);
+	lo_server_add_method(_server, "/ingen/set_variable", NULL, variable_set_cb, this);
 
 	// Queries
-	lo_server_add_method(_server, "/ingen/request_metadata", "iss", metadata_get_cb, this);
+	lo_server_add_method(_server, "/ingen/request_variable", "iss", variable_get_cb, this);
 	lo_server_add_method(_server, "/ingen/request_plugin", "is", request_plugin_cb, this);
 	lo_server_add_method(_server, "/ingen/request_object", "is", request_object_cb, this);
 	lo_server_add_method(_server, "/ingen/request_port_value", "is", request_port_value_cb, this);
@@ -836,14 +836,14 @@ OSCEngineReceiver::_midi_learn_cb(const char* path, const char* types, lo_arg**
 
 
 /** \page engine_osc_namespace
- * <p> \b /ingen/set_metadata - Sets a piece of metadata, associated with a synth-space object (node, etc)
+ * <p> \b /ingen/set_variable - Sets a piece of variable, associated with a synth-space object (node, etc)
  * \arg \b response-id (integer)
- * \arg \b object-path (string) - Full path of object to associate metadata with
- * \arg \b key (string) - Key (index) for new piece of metadata
- * \arg \b value (string) - Value of new piece of metadata </p> \n \n
+ * \arg \b object-path (string) - Full path of object to associate variable with
+ * \arg \b key (string) - Key (index) for new piece of variable
+ * \arg \b value (string) - Value of new piece of variable </p> \n \n
  */
 int
-OSCEngineReceiver::_metadata_set_cb(const char* path, const char* types, lo_arg** argv, int argc, lo_message msg)
+OSCEngineReceiver::_variable_set_cb(const char* path, const char* types, lo_arg** argv, int argc, lo_message msg)
 {
 	if (argc != 4 || types[0] != 'i' || types[1] != 's' || types[2] != 's')
 		return 1;
@@ -853,26 +853,26 @@ OSCEngineReceiver::_metadata_set_cb(const char* path, const char* types, lo_arg*
 	
 	Raul::Atom value = Raul::AtomLiblo::lo_arg_to_atom(types[3], argv[3]);
 	
-	set_metadata(object_path, key, value);
+	set_variable(object_path, key, value);
 	return 0;
 }
 
 
 /** \page engine_osc_namespace
- * <p> \b /ingen/request_metadata - Requests the engine send a piece of metadata, associated with a synth-space object (node, etc)
+ * <p> \b /ingen/request_variable - Requests the engine send a piece of variable, associated with a synth-space object (node, etc)
  * \arg \b response-id (integer)
- * \arg \b object-path (string) - Full path of object metadata is associated with
- * \arg \b key (string) - Key (index) for piece of metadata
+ * \arg \b object-path (string) - Full path of object variable is associated with
+ * \arg \b key (string) - Key (index) for piece of variable
  *
  * \li Reply will be sent to client registered with the source address of this message.</p> \n \n
  */
 int
-OSCEngineReceiver::_metadata_get_cb(const char* path, const char* types, lo_arg** argv, int argc, lo_message msg)
+OSCEngineReceiver::_variable_get_cb(const char* path, const char* types, lo_arg** argv, int argc, lo_message msg)
 {
 	const char* object_path = &argv[1]->s;
 	const char* key         = &argv[2]->s;
 
-	request_metadata(object_path, key);
+	request_variable(object_path, key);
 	return 0;
 }
 
diff --git a/src/libs/engine/OSCEngineReceiver.hpp b/src/libs/engine/OSCEngineReceiver.hpp
index bdc346d6..0f9d4685 100644
--- a/src/libs/engine/OSCEngineReceiver.hpp
+++ b/src/libs/engine/OSCEngineReceiver.hpp
@@ -115,12 +115,12 @@ private:
 	LO_HANDLER(note_off);
 	LO_HANDLER(all_notes_off);
 	LO_HANDLER(midi_learn);
-	LO_HANDLER(metadata_get);
-	LO_HANDLER(metadata_set);
+	LO_HANDLER(variable_get);
+	LO_HANDLER(variable_set);
 	LO_HANDLER(request_plugin);
 	LO_HANDLER(request_object);
 	LO_HANDLER(request_port_value);
-	LO_HANDLER(request_metadata);
+	LO_HANDLER(request_variable);
 	LO_HANDLER(request_plugins);
 	LO_HANDLER(request_all_objects);
 
diff --git a/src/libs/engine/ObjectSender.cpp b/src/libs/engine/ObjectSender.cpp
index 87f35b2c..55dafaf4 100644
--- a/src/libs/engine/ObjectSender.cpp
+++ b/src/libs/engine/ObjectSender.cpp
@@ -60,10 +60,10 @@ ObjectSender::send_patch(ClientInterface* client, const PatchImpl* patch, bool r
 
 	}
 
-	// Send metadata
-	const GraphObjectImpl::MetadataMap& data = patch->metadata();
-	for (GraphObjectImpl::MetadataMap::const_iterator j = data.begin(); j != data.end(); ++j)
-		client->metadata_update(patch->path(), (*j).first, (*j).second);
+	// Send variable
+	const GraphObjectImpl::Variables& data = patch->variables();
+	for (GraphObjectImpl::Variables::const_iterator j = data.begin(); j != data.end(); ++j)
+		client->variable_change(patch->path(), (*j).first, (*j).second);
 	
 	if (patch->enabled())
 		client->patch_enabled(patch->path());
@@ -92,10 +92,10 @@ ObjectSender::send_node(ClientInterface* client, const NodeImpl* node, bool recu
 	
 	client->new_node(node->plugin()->uri(), node->path(), node->polyphonic(), node->num_ports());
 	
-	// Send metadata
-	const GraphObjectImpl::MetadataMap& data = node->metadata();
-	for (GraphObjectImpl::MetadataMap::const_iterator j = data.begin(); j != data.end(); ++j)
-		client->metadata_update(node->path(), (*j).first, (*j).second);
+	// Send variable
+	const GraphObjectImpl::Variables& data = node->variables();
+	for (GraphObjectImpl::Variables::const_iterator j = data.begin(); j != data.end(); ++j)
+		client->variable_change(node->path(), (*j).first, (*j).second);
 	
 	client->bundle_end();
 	
@@ -116,10 +116,10 @@ ObjectSender::send_port(ClientInterface* client, const PortImpl* port)
 
 	client->new_port(port->path(), port->type().uri(), port->is_output());
 	
-	// Send metadata
-	const GraphObjectImpl::MetadataMap& data = port->metadata();
-	for (GraphObjectImpl::MetadataMap::const_iterator j = data.begin(); j != data.end(); ++j)
-		client->metadata_update(port->path(), (*j).first, (*j).second);
+	// Send variable
+	const GraphObjectImpl::Variables& data = port->variables();
+	for (GraphObjectImpl::Variables::const_iterator j = data.begin(); j != data.end(); ++j)
+		client->variable_change(port->path(), (*j).first, (*j).second);
 	
 	// Send control value
 	if (port->type() == DataType::CONTROL) {
diff --git a/src/libs/engine/QueuedEngineInterface.cpp b/src/libs/engine/QueuedEngineInterface.cpp
index 9899916c..053c0ff8 100644
--- a/src/libs/engine/QueuedEngineInterface.cpp
+++ b/src/libs/engine/QueuedEngineInterface.cpp
@@ -305,7 +305,7 @@ QueuedEngineInterface::midi_learn(const string& node_path)
 
 
 void
-QueuedEngineInterface::set_metadata(const string& path,
+QueuedEngineInterface::set_variable(const string& path,
                                     const string& predicate,
                                     const Atom&   value)
 {
@@ -347,7 +347,7 @@ QueuedEngineInterface::request_port_value(const string& port_path)
 }
 
 void
-QueuedEngineInterface::request_metadata(const string& object_path, const string& key)
+QueuedEngineInterface::request_variable(const string& object_path, const string& key)
 {
 	push_queued(new RequestMetadataEvent(_engine, _responder, now(), object_path, key));
 }
diff --git a/src/libs/engine/QueuedEngineInterface.hpp b/src/libs/engine/QueuedEngineInterface.hpp
index c860c0f8..ea4be595 100644
--- a/src/libs/engine/QueuedEngineInterface.hpp
+++ b/src/libs/engine/QueuedEngineInterface.hpp
@@ -150,7 +150,7 @@ public:
 
 	virtual void midi_learn(const string& node_path);
 
-	virtual void set_metadata(const string&     path,
+	virtual void set_variable(const string&     path,
 	                          const string&     predicate,
 	                          const Raul::Atom& value);
 	
@@ -164,7 +164,7 @@ public:
 	
 	virtual void request_port_value(const string& port_path);
 	
-	virtual void request_metadata(const string& object_path, const string& key);
+	virtual void request_variable(const string& object_path, const string& key);
 
 	virtual void request_plugins();
 
diff --git a/src/libs/engine/events/RequestMetadataEvent.cpp b/src/libs/engine/events/RequestMetadataEvent.cpp
index 0567d94d..99f0e04e 100644
--- a/src/libs/engine/events/RequestMetadataEvent.cpp
+++ b/src/libs/engine/events/RequestMetadataEvent.cpp
@@ -48,7 +48,7 @@ RequestMetadataEvent::pre_process()
 		}
 	}
 
-	_value = _object->get_metadata(_key);
+	_value = _object->get_variable(_key);
 	
 	QueuedEvent::pre_process();
 }
@@ -59,12 +59,12 @@ RequestMetadataEvent::post_process()
 {
 	if (_responder->client()) {
 		if (!_object) {
-			string msg = "Unable to find metadata subject ";
+			string msg = "Unable to find variable subject ";
 			msg += _path;
 			_responder->respond_error(msg);
 		} else {
 			_responder->respond_ok();
-			_responder->client()->metadata_update(_path, _key, _value);
+			_responder->client()->variable_change(_path, _key, _value);
 		}
 	} else {
 		_responder->respond_error("Unknown client");
diff --git a/src/libs/engine/events/RequestMetadataEvent.hpp b/src/libs/engine/events/RequestMetadataEvent.hpp
index bbc2c871..71f55399 100644
--- a/src/libs/engine/events/RequestMetadataEvent.hpp
+++ b/src/libs/engine/events/RequestMetadataEvent.hpp
@@ -31,7 +31,7 @@ namespace Shared {
 } using Shared::ClientInterface;
 
 
-/** A request from a client for a piece of metadata.
+/** A request from a client for a piece of variable.
  *
  * \ingroup engine
  */
diff --git a/src/libs/engine/events/SetMetadataEvent.cpp b/src/libs/engine/events/SetMetadataEvent.cpp
index ee0a62dc..2829eb1e 100644
--- a/src/libs/engine/events/SetMetadataEvent.cpp
+++ b/src/libs/engine/events/SetMetadataEvent.cpp
@@ -47,7 +47,7 @@ SetMetadataEvent::pre_process()
 		return;
 	}
 
-	_object->set_metadata(_key, _value);
+	_object->set_variable(_key, _value);
 
 	QueuedEvent::pre_process();
 }
@@ -70,7 +70,7 @@ SetMetadataEvent::post_process()
 		_responder->respond_error(msg);
 	} else {
 		_responder->respond_ok();
-		_engine.broadcaster()->send_metadata_update(_path, _key, _value);
+		_engine.broadcaster()->send_variable_change(_path, _key, _value);
 	}
 }
 
diff --git a/src/libs/engine/events/SetMetadataEvent.hpp b/src/libs/engine/events/SetMetadataEvent.hpp
index e65763c4..1d6a913e 100644
--- a/src/libs/engine/events/SetMetadataEvent.hpp
+++ b/src/libs/engine/events/SetMetadataEvent.hpp
@@ -29,7 +29,7 @@ namespace Ingen {
 class GraphObjectImpl;
 
 
-/** An event to set a piece of metadata for an GraphObjectImpl.
+/** An event to set a piece of variable for an GraphObjectImpl.
  *
  * \ingroup engine
  */
diff --git a/src/libs/gui/App.hpp b/src/libs/gui/App.hpp
index 196bdd96..956ac9bd 100644
--- a/src/libs/gui/App.hpp
+++ b/src/libs/gui/App.hpp
@@ -146,7 +146,7 @@ protected:
 	ActivityPorts _activity_ports;
 
 	/** Used to avoid feedback loops with (eg) process checkbutton
-	 * FIXME: Maybe this should be globally implemented at the Controller level,
+	 * FIXME: This should probably be implemented globally:
 	 * disable all command sending while handling events to avoid feedback
 	 * issues with widget event callbacks?  This same pattern is duplicated
 	 * too much... */
diff --git a/src/libs/gui/Configuration.hpp b/src/libs/gui/Configuration.hpp
index ab96cc80..0a3f94db 100644
--- a/src/libs/gui/Configuration.hpp
+++ b/src/libs/gui/Configuration.hpp
@@ -29,8 +29,6 @@ struct Coord { double x; double y; };
 namespace Ingen {
 namespace GUI {
 
-class Controller;
-
 
 /** Singleton state manager for the entire app.
  *
diff --git a/src/libs/gui/ConnectWindow.hpp b/src/libs/gui/ConnectWindow.hpp
index 086da446..315ae0b2 100644
--- a/src/libs/gui/ConnectWindow.hpp
+++ b/src/libs/gui/ConnectWindow.hpp
@@ -37,7 +37,6 @@ namespace Ingen {
 namespace GUI {
 
 class App;
-class Controller;
 
 
 /** The initially visible "Connect to engine" window.
diff --git a/src/libs/gui/LoadPatchWindow.cpp b/src/libs/gui/LoadPatchWindow.cpp
index 672ff940..9c31c64c 100644
--- a/src/libs/gui/LoadPatchWindow.cpp
+++ b/src/libs/gui/LoadPatchWindow.cpp
@@ -68,7 +68,7 @@ LoadPatchWindow::LoadPatchWindow(BaseObjectType* cobject, const Glib::RefPtr<Gno
 
 
 void
-LoadPatchWindow::present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+LoadPatchWindow::present(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	set_patch(patch);
 	_initial_data = data;
diff --git a/src/libs/gui/LoadPatchWindow.hpp b/src/libs/gui/LoadPatchWindow.hpp
index 9a4cf210..4f4ff30c 100644
--- a/src/libs/gui/LoadPatchWindow.hpp
+++ b/src/libs/gui/LoadPatchWindow.hpp
@@ -51,7 +51,7 @@ public:
 	void set_replace() { _replace = true; }
 	void set_merge()   { _replace = false; }
 
-	void present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data);
+	void present(SharedPtr<PatchModel> patch, GraphObject::Variables data);
 
 protected:
 	void on_show();
@@ -62,7 +62,7 @@ private:
 	void ok_clicked();
 	void cancel_clicked();
 
-	GraphObject::MetadataMap _initial_data;
+	GraphObject::Variables _initial_data;
 
 	SharedPtr<PatchModel> _patch;
 	bool                   _replace;
diff --git a/src/libs/gui/LoadPluginWindow.cpp b/src/libs/gui/LoadPluginWindow.cpp
index 2c9161c3..cc488210 100644
--- a/src/libs/gui/LoadPluginWindow.cpp
+++ b/src/libs/gui/LoadPluginWindow.cpp
@@ -109,7 +109,7 @@ LoadPluginWindow::LoadPluginWindow(BaseObjectType* cobject, const Glib::RefPtr<G
 
 
 void
-LoadPluginWindow::present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+LoadPluginWindow::present(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	set_patch(patch);
 	_initial_data = data;
@@ -341,8 +341,8 @@ LoadPluginWindow::add_clicked()
 		} else {
 			Path path = _patch->path().base() + Path::nameify(name);
 			App::instance().engine()->create_node(path, plugin->uri(), polyphonic);
-			for (GraphObject::MetadataMap::const_iterator i = _initial_data.begin(); i != _initial_data.end(); ++i)
-				App::instance().engine()->set_metadata(path, i->first, i->second);
+			for (GraphObject::Variables::const_iterator i = _initial_data.begin(); i != _initial_data.end(); ++i)
+				App::instance().engine()->set_variable(path, i->first, i->second);
 			++_plugin_name_offset;
 			_node_name_entry->set_text(generate_module_name(_plugin_name_offset));
 			
diff --git a/src/libs/gui/LoadPluginWindow.hpp b/src/libs/gui/LoadPluginWindow.hpp
index c0b668ba..4ab4b0e7 100644
--- a/src/libs/gui/LoadPluginWindow.hpp
+++ b/src/libs/gui/LoadPluginWindow.hpp
@@ -96,7 +96,7 @@ public:
 	void add_plugin(SharedPtr<PluginModel> plugin);
 	bool has_shown() const { return _has_shown; }
 
-	void present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data);
+	void present(SharedPtr<PatchModel> patch, GraphObject::Variables data);
 
 protected:
 	void on_show();
@@ -117,7 +117,7 @@ private:
 	void plugin_selection_changed();
 	string generate_module_name(int offset = 0);
 
-	GraphObject::MetadataMap _initial_data;
+	GraphObject::Variables _initial_data;
 
 	SharedPtr<PatchModel> _patch;
 
diff --git a/src/libs/gui/LoadRemotePatchWindow.cpp b/src/libs/gui/LoadRemotePatchWindow.cpp
index c6020ead..4c529d40 100644
--- a/src/libs/gui/LoadRemotePatchWindow.cpp
+++ b/src/libs/gui/LoadRemotePatchWindow.cpp
@@ -60,7 +60,7 @@ LoadRemotePatchWindow::LoadRemotePatchWindow(BaseObjectType* cobject, const Glib
 
 
 void
-LoadRemotePatchWindow::present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+LoadRemotePatchWindow::present(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	_liststore->clear();
 
diff --git a/src/libs/gui/LoadRemotePatchWindow.hpp b/src/libs/gui/LoadRemotePatchWindow.hpp
index 59b037d2..ca0ca814 100644
--- a/src/libs/gui/LoadRemotePatchWindow.hpp
+++ b/src/libs/gui/LoadRemotePatchWindow.hpp
@@ -63,7 +63,7 @@ public:
 	void set_replace() { _replace = true; }
 	void set_merge()   { _replace = false; }
 
-	void present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data);
+	void present(SharedPtr<PatchModel> patch, GraphObject::Variables data);
 
 private:
 	void patch_activated(const Gtk::TreeModel::Path& path, Gtk::TreeViewColumn* col);
@@ -72,7 +72,7 @@ private:
 	void open_clicked();
 	void cancel_clicked();
 
-	GraphObject::MetadataMap _initial_data;
+	GraphObject::Variables _initial_data;
 
 	SharedPtr<PatchModel> _patch;
 	bool                  _replace;
diff --git a/src/libs/gui/LoadSubpatchWindow.cpp b/src/libs/gui/LoadSubpatchWindow.cpp
index e230720a..2fdbf094 100644
--- a/src/libs/gui/LoadSubpatchWindow.cpp
+++ b/src/libs/gui/LoadSubpatchWindow.cpp
@@ -71,7 +71,7 @@ LoadSubpatchWindow::LoadSubpatchWindow(BaseObjectType* cobject, const Glib::RefP
 
 
 void
-LoadSubpatchWindow::present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+LoadSubpatchWindow::present(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	set_patch(patch);
 	_initial_data = data;
diff --git a/src/libs/gui/LoadSubpatchWindow.hpp b/src/libs/gui/LoadSubpatchWindow.hpp
index 89600895..ee8a5a16 100644
--- a/src/libs/gui/LoadSubpatchWindow.hpp
+++ b/src/libs/gui/LoadSubpatchWindow.hpp
@@ -44,7 +44,7 @@ public:
 
 	void set_patch(SharedPtr<PatchModel> patch);
 	
-	void present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data);
+	void present(SharedPtr<PatchModel> patch, GraphObject::Variables data);
 
 protected:
 	void on_show();
@@ -58,7 +58,7 @@ private:
 	void ok_clicked();
 	void cancel_clicked();
 
-	GraphObject::MetadataMap _initial_data;
+	GraphObject::Variables _initial_data;
 
 	SharedPtr<PatchModel> _patch;
 	
diff --git a/src/libs/gui/NewSubpatchWindow.cpp b/src/libs/gui/NewSubpatchWindow.cpp
index 54a0abb9..69c8471e 100644
--- a/src/libs/gui/NewSubpatchWindow.cpp
+++ b/src/libs/gui/NewSubpatchWindow.cpp
@@ -43,7 +43,7 @@ NewSubpatchWindow::NewSubpatchWindow(BaseObjectType* cobject, const Glib::RefPtr
 }
 
 void
-NewSubpatchWindow::present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+NewSubpatchWindow::present(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	set_patch(patch);
 	_initial_data = data;
@@ -91,8 +91,8 @@ NewSubpatchWindow::ok_clicked()
 	const uint32_t poly = _poly_spinbutton->get_value_as_int();
 
 	App::instance().engine()->create_patch(path, poly);
-	for (GraphObject::MetadataMap::const_iterator i = _initial_data.begin(); i != _initial_data.end(); ++i)
-		App::instance().engine()->set_metadata(path, i->first, i->second);
+	for (GraphObject::Variables::const_iterator i = _initial_data.begin(); i != _initial_data.end(); ++i)
+		App::instance().engine()->set_variable(path, i->first, i->second);
 
 	App::instance().engine()->enable_patch(path);
 	
diff --git a/src/libs/gui/NewSubpatchWindow.hpp b/src/libs/gui/NewSubpatchWindow.hpp
index d8fbde88..00fb6a3b 100644
--- a/src/libs/gui/NewSubpatchWindow.hpp
+++ b/src/libs/gui/NewSubpatchWindow.hpp
@@ -44,14 +44,14 @@ public:
 
 	void set_patch(SharedPtr<PatchModel> patch);
 
-	void present(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data);
+	void present(SharedPtr<PatchModel> patch, GraphObject::Variables data);
 
 private:
 	void name_changed();
 	void ok_clicked();
 	void cancel_clicked();
 
-	GraphObject::MetadataMap _initial_data;
+	GraphObject::Variables _initial_data;
 	SharedPtr<PatchModel>    _patch;
 	
 	Gtk::Entry*      _name_entry;
diff --git a/src/libs/gui/NodeModule.cpp b/src/libs/gui/NodeModule.cpp
index b4309dfa..a0ca3992 100644
--- a/src/libs/gui/NodeModule.cpp
+++ b/src/libs/gui/NodeModule.cpp
@@ -49,7 +49,7 @@ NodeModule::NodeModule(boost::shared_ptr<PatchCanvas> canvas, SharedPtr<NodeMode
 
 	node->signal_new_port.connect(sigc::bind(sigc::mem_fun(this, &NodeModule::add_port), true));
 	node->signal_removed_port.connect(sigc::mem_fun(this, &NodeModule::remove_port));
-	node->signal_metadata.connect(sigc::mem_fun(this, &NodeModule::set_metadata));
+	node->signal_variable.connect(sigc::mem_fun(this, &NodeModule::set_variable));
 	node->signal_polyphonic.connect(sigc::mem_fun(this, &NodeModule::set_stacked_border));
 	node->signal_renamed.connect(sigc::mem_fun(this, &NodeModule::rename));
 	
@@ -92,8 +92,8 @@ NodeModule::create(boost::shared_ptr<PatchCanvas> canvas, SharedPtr<NodeModel> n
 	else
 		ret = boost::shared_ptr<NodeModule>(new NodeModule(canvas, node));
 
-	for (GraphObject::MetadataMap::const_iterator m = node->metadata().begin(); m != node->metadata().end(); ++m)
-		ret->set_metadata(m->first, m->second);
+	for (GraphObject::Variables::const_iterator m = node->variables().begin(); m != node->variables().end(); ++m)
+		ret->set_variable(m->first, m->second);
 
 	for (PortModelList::const_iterator p = node->ports().begin(); p != node->ports().end(); ++p) {
 		ret->add_port(*p, false);
@@ -342,19 +342,19 @@ NodeModule::store_location()
 	const float x = static_cast<float>(property_x());
 	const float y = static_cast<float>(property_y());
 	
-	const Atom& existing_x = _node->get_metadata("ingenuity:canvas-x");
-	const Atom& existing_y = _node->get_metadata("ingenuity:canvas-y");
+	const Atom& existing_x = _node->get_variable("ingenuity:canvas-x");
+	const Atom& existing_y = _node->get_variable("ingenuity:canvas-y");
 	
 	if (existing_x.type() != Atom::FLOAT || existing_y.type() != Atom::FLOAT
 			|| existing_x.get_float() != x || existing_y.get_float() != y) {
-		App::instance().engine()->set_metadata(_node->path(), "ingenuity:canvas-x", Atom(x));
-		App::instance().engine()->set_metadata(_node->path(), "ingenuity:canvas-y", Atom(y));
+		App::instance().engine()->set_variable(_node->path(), "ingenuity:canvas-x", Atom(x));
+		App::instance().engine()->set_variable(_node->path(), "ingenuity:canvas-y", Atom(y));
 	}
 }
 
 
 void
-NodeModule::set_metadata(const string& key, const Atom& value)
+NodeModule::set_variable(const string& key, const Atom& value)
 {
 	if (key == "ingenuity:canvas-x" && value.type() == Atom::FLOAT)
 		move_to(value.get_float(), property_y());
diff --git a/src/libs/gui/NodeModule.hpp b/src/libs/gui/NodeModule.hpp
index 32e9220d..dcfd97dd 100644
--- a/src/libs/gui/NodeModule.hpp
+++ b/src/libs/gui/NodeModule.hpp
@@ -71,7 +71,7 @@ protected:
 	bool popup_gui();
 	
 	void rename();
-	void set_metadata(const std::string& key, const Atom& value);
+	void set_variable(const std::string& key, const Atom& value);
 	
 	void add_port(SharedPtr<PortModel> port, bool resize=true);
 	void remove_port(SharedPtr<PortModel> port);
diff --git a/src/libs/gui/ObjectMenu.hpp b/src/libs/gui/ObjectMenu.hpp
index 1acc278f..ab9eb30e 100644
--- a/src/libs/gui/ObjectMenu.hpp
+++ b/src/libs/gui/ObjectMenu.hpp
@@ -29,7 +29,6 @@ using Ingen::Client::ObjectModel;
 namespace Ingen {
 namespace GUI {
 
-class Controller;
 class ObjectControlWindow;
 class ObjectPropertiesWindow;
 class PatchCanvas;
diff --git a/src/libs/gui/PatchCanvas.cpp b/src/libs/gui/PatchCanvas.cpp
index 07301aa4..3f0e2716 100644
--- a/src/libs/gui/PatchCanvas.cpp
+++ b/src/libs/gui/PatchCanvas.cpp
@@ -357,9 +357,9 @@ PatchCanvas::connect(boost::shared_ptr<FlowCanvas::Connectable> src_port,
 		SharedPtr<PluginModel> pm(new PluginModel(PluginModel::Internal, "", "midi_control_in", ""));
 		SharedPtr<NodeModel> nm(new NodeModel(pm, _patch->path().base()
 			+ src->name() + "-" + dst->name(), false));
-		nm->set_metadata("canvas-x", Atom((float)
+		nm->set_variable("canvas-x", Atom((float)
 			(dst->module()->property_x() - dst->module()->width() - 20)));
-		nm->set_metadata("canvas-y", Atom((float)
+		nm->set_variable("canvas-y", Atom((float)
 			(dst->module()->property_y())));
 		App::instance().engine()->create_node_from_model(nm.get());
 		App::instance().engine()->connect(src->model()->path(), nm->path() + "/MIDI_In");
@@ -369,9 +369,9 @@ PatchCanvas::connect(boost::shared_ptr<FlowCanvas::Connectable> src_port,
 		// Set control node range to port's user range
 		
 		App::instance().engine()->set_port_value_queued(nm->path().base() + "Min",
-			dst->model()->get_metadata("user-min").get_float());
+			dst->model()->get_variable("user-min").get_float());
 		App::instance().engine()->set_port_value_queued(nm->path().base() + "Max",
-			dst->model()->get_metadata("user-max").get_float());
+			dst->model()->get_variable("user-max").get_float());
 #endif
 	} else {
 		App::instance().engine()->connect(src->model()->path(), dst->model()->path());
@@ -510,7 +510,7 @@ PatchCanvas::menu_add_control(ControlType type)
 {
 	// FIXME: bundleify
 
-	GraphObject::MetadataMap data = get_initial_data();
+	GraphObject::Variables data = get_initial_data();
 	float x = data["ingenuity:canvas-x"].get_float();
 	float y = data["ingenuity:canvas-y"].get_float();
 	
@@ -526,9 +526,9 @@ PatchCanvas::menu_add_port(const string& name, const string& type, bool is_outpu
 	// FIXME: bundleify
 	const Path& path = _patch->path().base() + generate_port_name(name);
 	App::instance().engine()->create_port(path, type, is_output);
-	GraphObject::MetadataMap data = get_initial_data();
-	for (GraphObject::MetadataMap::const_iterator i = data.begin(); i != data.end(); ++i)
-		App::instance().engine()->set_metadata(path, i->first, i->second);
+	GraphObject::Variables data = get_initial_data();
+	for (GraphObject::Variables::const_iterator i = data.begin(); i != data.end(); ++i)
+		App::instance().engine()->set_variable(path, i->first, i->second);
 }
 
 
@@ -538,9 +538,9 @@ PatchCanvas::load_plugin(SharedPtr<PluginModel> plugin)
 	const Path& path = _patch->path().base() + plugin->default_node_name(_patch);
 	// FIXME: polyphony?
 	App::instance().engine()->create_node(path, plugin->uri(), false);
-	GraphObject::MetadataMap data = get_initial_data();
-	for (GraphObject::MetadataMap::const_iterator i = data.begin(); i != data.end(); ++i)
-		App::instance().engine()->set_metadata(path, i->first, i->second);
+	GraphObject::Variables data = get_initial_data();
+	for (GraphObject::Variables::const_iterator i = data.begin(); i != data.end(); ++i)
+		App::instance().engine()->set_variable(path, i->first, i->second);
 }
 
 
@@ -557,10 +557,10 @@ PatchCanvas::get_new_module_location(double& x, double& y)
 }
 
 
-GraphObject::MetadataMap
+GraphObject::Variables
 PatchCanvas::get_initial_data()
 {
-	GraphObject::MetadataMap result;
+	GraphObject::Variables result;
 	
 	result["ingenuity:canvas-x"] = Atom((float)_last_click_x);
 	result["ingenuity:canvas-y"] = Atom((float)_last_click_y);
diff --git a/src/libs/gui/PatchCanvas.hpp b/src/libs/gui/PatchCanvas.hpp
index 95b7fc70..fdd7cb34 100644
--- a/src/libs/gui/PatchCanvas.hpp
+++ b/src/libs/gui/PatchCanvas.hpp
@@ -100,7 +100,7 @@ private:
 		SLV2PluginClass plugin_class, SLV2PluginClasses classes);
 #endif
 	
-	GraphObject::MetadataMap get_initial_data();
+	GraphObject::Variables get_initial_data();
 
 	bool canvas_event(GdkEvent* event);
 	
diff --git a/src/libs/gui/PatchPortModule.cpp b/src/libs/gui/PatchPortModule.cpp
index 2c5581f8..de0ed445 100644
--- a/src/libs/gui/PatchPortModule.cpp
+++ b/src/libs/gui/PatchPortModule.cpp
@@ -44,8 +44,8 @@ PatchPortModule::PatchPortModule(boost::shared_ptr<PatchCanvas> canvas, SharedPt
 
 	/*resize();
 
-	const Atom& x_atom = port->get_metadata("ingenuity:canvas-x");
-	const Atom& y_atom = port->get_metadata("ingenuity:canvas-y");
+	const Atom& x_atom = port->get_variable("ingenuity:canvas-x");
+	const Atom& y_atom = port->get_variable("ingenuity:canvas-y");
 
 	if (x_atom && y_atom && x_atom.type() == Atom::FLOAT && y_atom.type() == Atom::FLOAT) {
 		move_to(x_atom.get_float(), y_atom.get_float());
@@ -58,7 +58,7 @@ PatchPortModule::PatchPortModule(boost::shared_ptr<PatchCanvas> canvas, SharedPt
 	
 	set_stacked_border(port->polyphonic());
 
-	port->signal_metadata.connect(sigc::mem_fun(this, &PatchPortModule::metadata_update));
+	port->signal_variable.connect(sigc::mem_fun(this, &PatchPortModule::variable_change));
 	port->signal_polyphonic.connect(sigc::mem_fun(this, &PatchPortModule::set_stacked_border));
 }
 
@@ -76,8 +76,8 @@ PatchPortModule::create(boost::shared_ptr<PatchCanvas> canvas, SharedPtr<PortMod
 
 	ret->set_menu(ret->_patch_port->menu());
 	
-	for (GraphObject::MetadataMap::const_iterator m = port->metadata().begin(); m != port->metadata().end(); ++m)
-		ret->metadata_update(m->first, m->second);
+	for (GraphObject::Variables::const_iterator m = port->variables().begin(); m != port->variables().end(); ++m)
+		ret->variable_change(m->first, m->second);
 	
 	ret->resize();
 
@@ -102,19 +102,19 @@ PatchPortModule::store_location()
 	const float x = static_cast<float>(property_x());
 	const float y = static_cast<float>(property_y());
 	
-	const Atom& existing_x = _port->get_metadata("ingenuity:canvas-x");
-	const Atom& existing_y = _port->get_metadata("ingenuity:canvas-y");
+	const Atom& existing_x = _port->get_variable("ingenuity:canvas-x");
+	const Atom& existing_y = _port->get_variable("ingenuity:canvas-y");
 	
 	if (existing_x.type() != Atom::FLOAT || existing_y.type() != Atom::FLOAT
 			|| existing_x.get_float() != x || existing_y.get_float() != y) {
-		App::instance().engine()->set_metadata(_port->path(), "ingenuity:canvas-x", Atom(x));
-		App::instance().engine()->set_metadata(_port->path(), "ingenuity:canvas-y", Atom(y));
+		App::instance().engine()->set_variable(_port->path(), "ingenuity:canvas-x", Atom(x));
+		App::instance().engine()->set_variable(_port->path(), "ingenuity:canvas-y", Atom(y));
 	}
 }
 
 
 void
-PatchPortModule::metadata_update(const string& key, const Atom& value)
+PatchPortModule::variable_change(const string& key, const Atom& value)
 {
 	if (key == "ingenuity:canvas-x" && value.type() == Atom::FLOAT)
 		move_to(value.get_float(), property_y());
diff --git a/src/libs/gui/PatchPortModule.hpp b/src/libs/gui/PatchPortModule.hpp
index 8f3a3fc6..c9c5625d 100644
--- a/src/libs/gui/PatchPortModule.hpp
+++ b/src/libs/gui/PatchPortModule.hpp
@@ -62,7 +62,7 @@ public:
 protected:
 	PatchPortModule(boost::shared_ptr<PatchCanvas> canvas, SharedPtr<PortModel> port);
 
-	void metadata_update(const string& key, const Raul::Atom& value);
+	void variable_change(const string& key, const Raul::Atom& value);
 	void create_menu();
 
 	SharedPtr<PortModel> _port;
diff --git a/src/libs/gui/PatchPropertiesWindow.cpp b/src/libs/gui/PatchPropertiesWindow.cpp
index eb5120c4..2f0956e6 100644
--- a/src/libs/gui/PatchPropertiesWindow.cpp
+++ b/src/libs/gui/PatchPropertiesWindow.cpp
@@ -48,11 +48,11 @@ PatchPropertiesWindow::set_patch(SharedPtr<PatchModel> patch_model)
 	property_title() = patch_model->path() + " Properties";
 	_patch_model = patch_model;
 	
-	const Atom& author_atom = _patch_model->get_metadata("author");
+	const Atom& author_atom = _patch_model->get_variable("author");
 	_author_entry->set_text(
 		(author_atom.type() == Atom::STRING) ? author_atom.get_string() : "" );
 
-	const Atom& desc_atom = _patch_model->get_metadata("description");
+	const Atom& desc_atom = _patch_model->get_variable("description");
 	_textview->get_buffer()->set_text(
 		(desc_atom.type() == Atom::STRING) ? desc_atom.get_string() : "" );
 }
@@ -61,11 +61,11 @@ PatchPropertiesWindow::set_patch(SharedPtr<PatchModel> patch_model)
 void
 PatchPropertiesWindow::cancel_clicked()
 {
-	const Atom& author_atom = _patch_model->get_metadata("author");
+	const Atom& author_atom = _patch_model->get_variable("author");
 	_author_entry->set_text(
 		(author_atom.type() == Atom::STRING) ? author_atom.get_string() : "" );
 
-	const Atom& desc_atom = _patch_model->get_metadata("description");
+	const Atom& desc_atom = _patch_model->get_variable("description");
 	_textview->get_buffer()->set_text(
 		(desc_atom.type() == Atom::STRING) ? desc_atom.get_string() : "" );
 	
@@ -78,8 +78,8 @@ PatchPropertiesWindow::ok_clicked()
 {
 	cerr << "FIXME: properties\n";
 
-	//m_patch_model->set_metadata("author", Atom(_author_entry->get_text().c_str()));
-	//m_patch_model->set_metadata("description", Atom(_textview->get_buffer()->get_text().c_str()));
+	//m_patch_model->set_variable("author", Atom(_author_entry->get_text().c_str()));
+	//m_patch_model->set_variable("description", Atom(_textview->get_buffer()->get_text().c_str()));
 	hide();
 }
 
diff --git a/src/libs/gui/PatchWindow.cpp b/src/libs/gui/PatchWindow.cpp
index 3566d83d..716d4356 100644
--- a/src/libs/gui/PatchWindow.cpp
+++ b/src/libs/gui/PatchWindow.cpp
@@ -366,7 +366,7 @@ PatchWindow::event_save_as()
 		if (confirm) {
 			App::instance().loader()->save_patch(_patch, filename);
 			_patch->set_filename(filename);
-			//_patch->set_metadata("filename", Atom(filename.c_str()));
+			//_patch->set_variable("filename", Atom(filename.c_str()));
 		}
 	}
 	App::instance().configuration()->set_patch_folder(dialog.get_current_folder());
diff --git a/src/libs/gui/Port.cpp b/src/libs/gui/Port.cpp
index e3dd0fd4..b02c0856 100644
--- a/src/libs/gui/Port.cpp
+++ b/src/libs/gui/Port.cpp
@@ -62,7 +62,7 @@ Port::Port(boost::shared_ptr<FlowCanvas::Module> module, SharedPtr<PortModel> pm
 		set_control_min(min);
 		set_control_max(max);
 
-		pm->signal_metadata.connect(sigc::mem_fun(this, &Port::metadata_update));
+		pm->signal_variable.connect(sigc::mem_fun(this, &Port::variable_change));
 		_port_model->signal_control.connect(sigc::mem_fun(this, &Port::control_changed));
 	}
 		
@@ -116,7 +116,7 @@ Port::set_control(float value, bool signal)
 
 
 void
-Port::metadata_update(const string& key, const Atom& value)
+Port::variable_change(const string& key, const Atom& value)
 {
 	if ( (key == "ingen:minimum") && value.type() == Atom::FLOAT) {
 		set_control_min(value.get_float());
diff --git a/src/libs/gui/Port.hpp b/src/libs/gui/Port.hpp
index dbbf64d3..4af07389 100644
--- a/src/libs/gui/Port.hpp
+++ b/src/libs/gui/Port.hpp
@@ -52,7 +52,7 @@ public:
 	
 private:
 	
-	void metadata_update(const string& key, const Raul::Atom& value);
+	void variable_change(const string& key, const Raul::Atom& value);
 
 	void renamed();
 
diff --git a/src/libs/gui/PortPropertiesWindow.cpp b/src/libs/gui/PortPropertiesWindow.cpp
index a715a114..707c8d76 100644
--- a/src/libs/gui/PortPropertiesWindow.cpp
+++ b/src/libs/gui/PortPropertiesWindow.cpp
@@ -80,8 +80,8 @@ PortPropertiesWindow::present(SharedPtr<PortModel> pm)
 	_connections.push_back(_max_spinner->signal_value_changed().connect(
 				sigc::mem_fun(*this, &PortPropertiesWindow::max_changed)));
 	
-	_connections.push_back(pm->signal_metadata.connect(
-			sigc::mem_fun(this, &PortPropertiesWindow::metadata_update)));
+	_connections.push_back(pm->signal_variable.connect(
+			sigc::mem_fun(this, &PortPropertiesWindow::variable_change)));
 
 	_enable_signal = true;
 
@@ -90,7 +90,7 @@ PortPropertiesWindow::present(SharedPtr<PortModel> pm)
 
 
 void
-PortPropertiesWindow::metadata_update(const string& key, const Atom& value)
+PortPropertiesWindow::variable_change(const string& key, const Atom& value)
 {
 	_enable_signal = false;
 
@@ -115,7 +115,7 @@ PortPropertiesWindow::min_changed()
 	}
 
 	if (_enable_signal)
-		App::instance().engine()->set_metadata(_port_model->path(), "ingen:minimum", min);
+		App::instance().engine()->set_variable(_port_model->path(), "ingen:minimum", min);
 }
 
 
@@ -131,15 +131,15 @@ PortPropertiesWindow::max_changed()
 	}
 
 	if (_enable_signal)
-		App::instance().engine()->set_metadata(_port_model->path(), "ingen:maximum", max);
+		App::instance().engine()->set_variable(_port_model->path(), "ingen:maximum", max);
 }
 
 
 void
 PortPropertiesWindow::cancel()
 {
-	App::instance().engine()->set_metadata(_port_model->path(), "ingen:minimum", _initial_min);
-	App::instance().engine()->set_metadata(_port_model->path(), "ingen:maximum", _initial_max);
+	App::instance().engine()->set_variable(_port_model->path(), "ingen:minimum", _initial_min);
+	App::instance().engine()->set_variable(_port_model->path(), "ingen:maximum", _initial_max);
 	hide();
 }
 
diff --git a/src/libs/gui/PortPropertiesWindow.hpp b/src/libs/gui/PortPropertiesWindow.hpp
index 5d10960d..4580c7c6 100644
--- a/src/libs/gui/PortPropertiesWindow.hpp
+++ b/src/libs/gui/PortPropertiesWindow.hpp
@@ -42,7 +42,7 @@ public:
 	void present(SharedPtr<PortModel> port_model);
 
 private:
-	void metadata_update(const string& key, const Atom& value);
+	void variable_change(const string& key, const Atom& value);
 	void min_changed();
 	void max_changed();
 	
diff --git a/src/libs/gui/ThreadedLoader.cpp b/src/libs/gui/ThreadedLoader.cpp
index 3cac84f6..1b7725a9 100644
--- a/src/libs/gui/ThreadedLoader.cpp
+++ b/src/libs/gui/ThreadedLoader.cpp
@@ -74,12 +74,12 @@ ThreadedLoader::_whipped()
 }
 
 void
-ThreadedLoader::load_patch(bool                     merge,
-                           const string&            data_base_uri,
-                           const Path&              data_path,
-                           GraphObject::MetadataMap engine_data,
-                           optional<Path>           engine_parent,
-                           optional<const string&>  engine_name)
+ThreadedLoader::load_patch(bool                    merge,
+                           const string&           data_base_uri,
+                           const Path&             data_path,
+                           GraphObject::Variables  engine_data,
+                           optional<Path>          engine_parent,
+                           optional<const string&> engine_name)
 {
 	_mutex.lock();
 
diff --git a/src/libs/gui/ThreadedLoader.hpp b/src/libs/gui/ThreadedLoader.hpp
index 2e03c2a1..6c095925 100644
--- a/src/libs/gui/ThreadedLoader.hpp
+++ b/src/libs/gui/ThreadedLoader.hpp
@@ -61,12 +61,12 @@ public:
 	// FIXME: there's a pattern here....
 	// (same core interface as Loader/Serialiser)
 	
-	void load_patch(bool                     merge,
-	                const string&            data_base_uri,
-	                const Path&              data_path,
-	                GraphObject::MetadataMap engine_data,
-	                optional<Path>           engine_parent,
-	                optional<const string&>  engine_name = optional<const string&>());
+	void load_patch(bool                    merge,
+	                const string&           data_base_uri,
+	                const Path&             data_path,
+	                GraphObject::Variables  engine_data,
+	                optional<Path>          engine_parent,
+	                optional<const string&> engine_name = optional<const string&>());
 	
 	void save_patch(SharedPtr<PatchModel> model, const string& filename);
 
diff --git a/src/libs/gui/UploadPatchWindow.cpp b/src/libs/gui/UploadPatchWindow.cpp
index b5e414a1..57045a91 100644
--- a/src/libs/gui/UploadPatchWindow.cpp
+++ b/src/libs/gui/UploadPatchWindow.cpp
@@ -74,11 +74,11 @@ UploadPatchWindow::on_show()
 {
 	Gtk::Dialog::on_show();
 
-	Raul::Atom atom = _patch->get_metadata("lv2:symbol");
+	Raul::Atom atom = _patch->get_variable("lv2:symbol");
 	if (atom)
 		_symbol_entry->set_text(atom.get_string());
 	
-	atom = _patch->get_metadata("doap:name");
+	atom = _patch->get_variable("doap:name");
 	if (atom)
 		_short_name_entry->set_text(atom.get_string());
 }
@@ -237,11 +237,11 @@ UploadPatchWindow::upload_clicked()
 	Glib::ustring symbol = _symbol_entry->get_text();
 	Glib::ustring short_name = _short_name_entry->get_text();
 
-	_patch->set_metadata("lv2:symbol", Atom(symbol));
-	App::instance().engine()->set_metadata(_patch->path(), "lv2:symbol", Atom(symbol));
+	_patch->set_variable("lv2:symbol", Atom(symbol));
+	App::instance().engine()->set_variable(_patch->path(), "lv2:symbol", Atom(symbol));
 	
-	_patch->set_metadata("doap:name", Atom(short_name));
-	App::instance().engine()->set_metadata(_patch->path(), "doap:name", Atom(short_name));
+	_patch->set_variable("doap:name", Atom(short_name));
+	App::instance().engine()->set_variable(_patch->path(), "doap:name", Atom(short_name));
 
 	_response = 0;
 	_progress_pct = 0;
diff --git a/src/libs/gui/WindowFactory.cpp b/src/libs/gui/WindowFactory.cpp
index 6e7e2c8b..0d04eed9 100644
--- a/src/libs/gui/WindowFactory.cpp
+++ b/src/libs/gui/WindowFactory.cpp
@@ -253,7 +253,7 @@ WindowFactory::remove_control_window(NodeControlWindow* win, GdkEventAny* ignore
 
 
 void
-WindowFactory::present_load_plugin(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+WindowFactory::present_load_plugin(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	PatchWindowMap::iterator w = _patch_windows.find(patch->path());
 
@@ -265,7 +265,7 @@ WindowFactory::present_load_plugin(SharedPtr<PatchModel> patch, GraphObject::Met
 
 
 void
-WindowFactory::present_load_patch(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+WindowFactory::present_load_patch(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	PatchWindowMap::iterator w = _patch_windows.find(patch->path());
 
@@ -279,7 +279,7 @@ WindowFactory::present_load_patch(SharedPtr<PatchModel> patch, GraphObject::Meta
 
 	
 void
-WindowFactory::present_load_remote_patch(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+WindowFactory::present_load_remote_patch(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	PatchWindowMap::iterator w = _patch_windows.find(patch->path());
 
@@ -306,7 +306,7 @@ WindowFactory::present_upload_patch(SharedPtr<PatchModel> patch)
 }
 
 void
-WindowFactory::present_new_subpatch(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+WindowFactory::present_new_subpatch(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	PatchWindowMap::iterator w = _patch_windows.find(patch->path());
 
@@ -318,7 +318,7 @@ WindowFactory::present_new_subpatch(SharedPtr<PatchModel> patch, GraphObject::Me
 
 
 void
-WindowFactory::present_load_subpatch(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data)
+WindowFactory::present_load_subpatch(SharedPtr<PatchModel> patch, GraphObject::Variables data)
 {
 	PatchWindowMap::iterator w = _patch_windows.find(patch->path());
 
diff --git a/src/libs/gui/WindowFactory.hpp b/src/libs/gui/WindowFactory.hpp
index d9418496..06f2f637 100644
--- a/src/libs/gui/WindowFactory.hpp
+++ b/src/libs/gui/WindowFactory.hpp
@@ -64,12 +64,12 @@ public:
 
 	void present_controls(SharedPtr<NodeModel> node);
 
-	void present_load_plugin(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data=GraphObject::MetadataMap());
-	void present_load_patch(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data=GraphObject::MetadataMap());
-	void present_load_remote_patch(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data=GraphObject::MetadataMap());
+	void present_load_plugin(SharedPtr<PatchModel> patch, GraphObject::Variables data=GraphObject::Variables());
+	void present_load_patch(SharedPtr<PatchModel> patch, GraphObject::Variables data=GraphObject::Variables());
+	void present_load_remote_patch(SharedPtr<PatchModel> patch, GraphObject::Variables data=GraphObject::Variables());
 	void present_upload_patch(SharedPtr<PatchModel> patch);
-	void present_new_subpatch(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data=GraphObject::MetadataMap());
-	void present_load_subpatch(SharedPtr<PatchModel> patch, GraphObject::MetadataMap data=GraphObject::MetadataMap());
+	void present_new_subpatch(SharedPtr<PatchModel> patch, GraphObject::Variables data=GraphObject::Variables());
+	void present_load_subpatch(SharedPtr<PatchModel> patch, GraphObject::Variables data=GraphObject::Variables());
 	void present_rename(SharedPtr<ObjectModel> object);
 	void present_properties(SharedPtr<ObjectModel> object);
 	
diff --git a/src/libs/serialisation/Loader.cpp b/src/libs/serialisation/Loader.cpp
index 30958198..a52024aa 100644
--- a/src/libs/serialisation/Loader.cpp
+++ b/src/libs/serialisation/Loader.cpp
@@ -46,7 +46,7 @@ Loader::load(SharedPtr<EngineInterface> engine,
 		boost::optional<Path>           parent,
 		string                          patch_name,
 		Glib::ustring                   patch_uri,
-		GraphObject::MetadataMap        data)
+		GraphObject::Variables        data)
 {
 	setlocale(LC_NUMERIC, "C");
 
@@ -67,7 +67,7 @@ Loader::load(SharedPtr<EngineInterface> engine,
 	size_t patch_poly = 1;
 	
 	/* Use parameter overridden polyphony, if given */
-	GraphObject::MetadataMap::iterator poly_param = data.find("ingen:polyphony");
+	GraphObject::Variables::iterator poly_param = data.find("ingen:polyphony");
 	if (poly_param != data.end() && poly_param->second.type() == Atom::INT) {
 		patch_poly = poly_param->second.get_int32();
 	
@@ -127,7 +127,7 @@ Loader::load(SharedPtr<EngineInterface> engine,
 
 	RDF::Query::Results results = query.run(*rdf_world, model);
 
-	map<const string, const Atom> metadata;
+	map<const string, const Atom> variable;
 
 	for (RDF::Query::Results::iterator i = results.begin(); i != results.end(); ++i) {
 
@@ -146,13 +146,13 @@ Loader::load(SharedPtr<EngineInterface> engine,
 			created.insert(node_path);
 		}
 
-		/* Float metadata (FIXME: use using raw predicates is definitely a very
+		/* Float variable (FIXME: use using raw predicates is definitely a very
 		 * bad idea, make an ingen:Variable or something */
 		const string floatkey = rdf_world->prefixes().qualify((*i)["floatkey"].to_string());
 		RDF::Node val_node = (*i)["floatval"];
 
 		if (floatkey != "" && val_node.is_float())
-			engine->set_metadata(node_path, floatkey, val_node.to_float());
+			engine->set_variable(node_path, floatkey, val_node.to_float());
 	}
 		
 
@@ -250,7 +250,7 @@ Loader::load(SharedPtr<EngineInterface> engine,
 		val_node = (*i)["floatval"];
 
 		if (floatkey != "" && val_node.is_float())
-			engine->set_metadata(patch_path.base() + name, floatkey, Atom(val_node.to_float()));
+			engine->set_variable(patch_path.base() + name, floatkey, Atom(val_node.to_float()));
 	}
 
 	created.clear();
@@ -337,7 +337,7 @@ Loader::load(SharedPtr<EngineInterface> engine,
 	}
 
 
-	/* Load metadata */
+	/* Load variable */
 
 	query = RDF::Query(*rdf_world, Glib::ustring(
 			"SELECT DISTINCT ?floatkey ?floatval WHERE {\n") +
@@ -353,13 +353,13 @@ Loader::load(SharedPtr<EngineInterface> engine,
 		RDF::Node val_node = (*i)["floatval"];
 
 		if (floatkey != "" && val_node.is_float())
-			engine->set_metadata(patch_path, floatkey, Atom(val_node.to_float()));
+			engine->set_variable(patch_path, floatkey, Atom(val_node.to_float()));
 	}
 
 
-	// Set passed metadata last to override any loaded values
-	for (GraphObject::MetadataMap::const_iterator i = data.begin(); i != data.end(); ++i)
-		engine->set_metadata(patch_path, i->first, i->second);
+	// Set passed variable last to override any loaded values
+	for (GraphObject::Variables::const_iterator i = data.begin(); i != data.end(); ++i)
+		engine->set_variable(patch_path, i->first, i->second);
 
 
 	/* Enable */
diff --git a/src/libs/serialisation/Loader.hpp b/src/libs/serialisation/Loader.hpp
index d363bf28..e81fba4c 100644
--- a/src/libs/serialisation/Loader.hpp
+++ b/src/libs/serialisation/Loader.hpp
@@ -46,7 +46,7 @@ public:
 	     boost::optional<Raul::Path>               parent,
 	     std::string                               patch_name,
 	     Glib::ustring                             patch_uri = "",
-	     GraphObject::MetadataMap                  data = GraphObject::MetadataMap());
+	     GraphObject::Variables                  data = GraphObject::Variables());
 };
 
 
diff --git a/src/libs/serialisation/Serialiser.cpp b/src/libs/serialisation/Serialiser.cpp
index 15b7f753..b21b7c6d 100644
--- a/src/libs/serialisation/Serialiser.cpp
+++ b/src/libs/serialisation/Serialiser.cpp
@@ -283,8 +283,8 @@ Serialiser::serialize_patch(SharedPtr<Shared::Patch> patch)
 		"ingen:enabled",
 		Atom(patch->enabled()));
 	
-	for (GraphObject::MetadataMap::const_iterator m = patch->metadata().begin();
-			m != patch->metadata().end(); ++m) {
+	for (GraphObject::Variables::const_iterator m = patch->variables().begin();
+			m != patch->variables().end(); ++m) {
 		if (m->first.find(":") != string::npos) {
 			_model->add_statement(
 				patch_id,
@@ -370,8 +370,8 @@ Serialiser::serialize_node(SharedPtr<Shared::Node> node, const RDF::Node& node_i
 		_model->add_statement(node_id, "ingen:port", port_id);
 	}
 
-	for (GraphObject::MetadataMap::const_iterator m = node->metadata().begin();
-			m != node->metadata().end(); ++m) {
+	for (GraphObject::Variables::const_iterator m = node->variables().begin();
+			m != node->variables().end(); ++m) {
 		if (m->first.find(":") != string::npos) {
 			_model->add_statement(
 				node_id,
@@ -382,8 +382,8 @@ Serialiser::serialize_node(SharedPtr<Shared::Node> node, const RDF::Node& node_i
 }
 
 /** Writes a port subject with various information only if there are some
- * predicate/object pairs to go with it (eg if the port has metadata, or a value, or..).
- * Audio output ports with no metadata will not be written, for example.
+ * predicate/object pairs to go with it (eg if the port has variable, or a value, or..).
+ * Audio output ports with no variable will not be written, for example.
  */
 void
 Serialiser::serialize_port(const Port* port, const RDF::Node& port_id)
@@ -403,9 +403,9 @@ Serialiser::serialize_port(const Port* port, const RDF::Node& port_id)
 	if (port->type() == DataType::CONTROL && port->is_input())
 		_model->add_statement(port_id, "ingen:value", port->value());
 
-	if (port->metadata().size() > 0) {
-		for (GraphObject::MetadataMap::const_iterator m = port->metadata().begin();
-				m != port->metadata().end(); ++m) {
+	if (port->variables().size() > 0) {
+		for (GraphObject::Variables::const_iterator m = port->variables().begin();
+				m != port->variables().end(); ++m) {
 		if (m->first.find(":") != string::npos) {
 				_model->add_statement(
 						port_id,