Speed up iterating over an entire PortSet by keeping a

separate list of all ports.


git-svn-id: svn://localhost/ardour2/branches/3.0@11318 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/ardour/ardour/port_set.h

@@ -34,6 +34,10 @@ class MidiPort;
  * This allows access to all the ports as a list, ignoring type, or accessing
  * the nth port of a given type.  Note that port(n) and nth_audio_port(n) may
  * NOT return the same port.
+ *
+ * Each port is held twice; once in a per-type vector of vectors (_ports)
+ * and once in a vector of all port (_all_ports).  This is to speed up the
+ * fairly common case of iterating over all ports.
  */
 class PortSet : public boost::noncopyable {
 public:
@@ -60,7 +64,7 @@ public:
 	/** Remove all ports from the PortSet.  Ports are not deregistered with
 	 * the engine, it's the caller's responsibility to not leak here!
 	 */
-	void clear() { _ports.clear(); }
+	void clear();
 
 	const ChanCount& count() const { return _count; }
 
@@ -132,6 +136,8 @@ private:
 
 	// Vector of vectors, indexed by DataType::to_index()
 	std::vector<PortVec> _ports;
+	// All ports in _ports in one vector, to speed some operations
+	PortVec _all_ports;
 
 	ChanCount _count;
 };

libs/ardour/port_set.cc

@@ -71,14 +71,27 @@ static bool sort_ports_by_name (boost::shared_ptr<Port> a, boost::shared_ptr<Por
 	}
 }
 
+
+static bool sort_ports_by_type_and_name (boost::shared_ptr<Port> a, boost::shared_ptr<Port> b)
+{
+	if (a->type() != b->type()) {
+		return a->type() < b->type();
+	}
+
+	return sort_ports_by_name (a, b);
+}
+
 void
 PortSet::add (boost::shared_ptr<Port> port)
 {
 	PortVec& v = _ports[port->type()];
 
 	v.push_back(port);
+	_all_ports.push_back(port);
 
 	sort(v.begin(), v.end(), sort_ports_by_name);
+	sort(_all_ports.begin(), _all_ports.end(), sort_ports_by_type_and_name);
+	
 	_count.set(port->type(), _count.get(port->type()) + 1);
 	assert(_count.get(port->type()) == _ports[port->type()].size());
 }
@@ -86,6 +99,11 @@ PortSet::add (boost::shared_ptr<Port> port)
 bool
 PortSet::remove (boost::shared_ptr<Port> port)
 {
+	PortVec::iterator i = find(_all_ports.begin(), _all_ports.end(), port);
+	if (i != _all_ports.end()) {
+		_all_ports.erase(i);
+	}
+	
 	for (std::vector<PortVec>::iterator l = _ports.begin(); l != _ports.end(); ++l) {
 		PortVec::iterator i = find(l->begin(), l->end(), port);
 		if (i != l->end()) {
@@ -103,40 +121,20 @@ PortSet::remove (boost::shared_ptr<Port> port)
 size_t
 PortSet::num_ports() const
 {
-	size_t ret = 0;
-
-	for (std::vector<PortVec>::const_iterator l = _ports.begin(); l != _ports.end(); ++l)
-		ret += (*l).size();
-
-	return ret;
+	return _all_ports.size();
 }
 
 bool
 PortSet::contains (boost::shared_ptr<const Port> port) const
 {
-	for (std::vector<PortVec>::const_iterator l = _ports.begin(); l != _ports.end(); ++l)
-		if (find (l->begin(), l->end(), port) != l->end())
-			return true;
-
-	return false;
+	return find(_all_ports.begin(), _all_ports.end(), port) != _all_ports.end();
 }
 
 boost::shared_ptr<Port>
 PortSet::port(size_t n) const
 {
-	// This is awesome.  Awesomely slow.
-
-	size_t size_so_far = 0;
-
-	for (std::vector<PortVec>::const_iterator l = _ports.begin(); l != _ports.end(); ++l) {
-		if (n < size_so_far + l->size()) {
-			return (*l)[n - size_so_far];
-		} else {
-			size_so_far += l->size();
-		}
-	}
-
-	return boost::shared_ptr<Port> (); // n out of range
+	assert(n < _all_ports.size());
+	return _all_ports[n];
 }
 
 boost::shared_ptr<Port>
@@ -163,4 +161,11 @@ PortSet::nth_midi_port(size_t n) const
 	return boost::dynamic_pointer_cast<MidiPort> (port (DataType::MIDI, n));
 }
 
+void
+PortSet::clear()
+{
+	_ports.clear();
+	_all_ports.clear();
+}
+
 } // namepace ARDOUR