fix configurable IO MIDI FX w/strict-i/o

libs/ardour/ardour/audio_unit.h

@@ -235,7 +235,7 @@ class LIBARDOUR_API AUPluginInfo : public PluginInfo {
 
 	std::vector<Plugin::PresetRecord> get_presets (bool user_only) const;
 
-	bool needs_midi_input ();
+	bool needs_midi_input () const;
 	bool is_effect () const;
 	bool is_effect_without_midi_input () const;
 	bool is_effect_with_midi_input () const;

libs/ardour/ardour/luaproc.h

@@ -160,8 +160,10 @@ class LIBARDOUR_API LuaPluginInfo : public PluginInfo
 	PluginPtr load (Session& session);
 	std::vector<Plugin::PresetRecord> get_presets (bool user_only) const;
 
-	bool is_instrument () const { return false; }
+	bool is_instrument () const { return _is_instrument ; }
 	bool reconfigurable_io() const { return true; }
+
+	bool _is_instrument;
 };
 
 typedef boost::shared_ptr<LuaPluginInfo> LuaPluginInfoPtr;

libs/ardour/ardour/plugin.h

@@ -394,6 +394,7 @@ class LIBARDOUR_API PluginInfo {
 
 	virtual PluginPtr load (Session& session) = 0;
 	virtual bool is_instrument() const;
+	virtual bool needs_midi_input() const { return is_instrument (); }
 	virtual bool in_category (const std::string &) const { return false; }
 
 	virtual std::vector<Plugin::PresetRecord> get_presets (bool user_only) const = 0;

libs/ardour/ardour/plugin_insert.h

@@ -156,7 +156,7 @@ class LIBARDOUR_API PluginInsert : public Processor
 
 	bool has_no_inputs() const;
 	bool has_no_audio_inputs() const;
-	bool is_midi_instrument() const;
+	bool needs_midi_input() const;
 
 	void realtime_handle_transport_stopped ();
 	void realtime_locate ();

libs/ardour/audio_unit.cc

@@ -2679,6 +2679,8 @@ AUPluginInfo::discover_by_description (PluginInfoList& plugs, CAComponentDescrip
 			continue;
 		}
 
+		bool has_midi_in = false;
+
 		AUPluginInfoPtr info (new AUPluginInfo
 				      (boost::shared_ptr<CAComponentDescription> (new CAComponentDescription(temp))));
 
@@ -2703,9 +2705,11 @@ AUPluginInfo::discover_by_description (PluginInfoList& plugs, CAComponentDescrip
 			break;
 		case kAudioUnitType_MusicDevice:
 			info->category = _("AudioUnit Instruments");
+			has_midi_in = true;
 			break;
 		case kAudioUnitType_MusicEffect:
 			info->category = _("AudioUnit MusicEffects");
+			has_midi_in = true;
 			break;
 		case kAudioUnitType_Effect:
 			info->category = _("AudioUnit Effects");
@@ -2772,6 +2776,8 @@ AUPluginInfo::discover_by_description (PluginInfoList& plugs, CAComponentDescrip
 				info->n_inputs.set (DataType::AUDIO, 1);
 			}
 
+			info->n_inputs.set (DataType::MIDI, has_midi_in ? 1 ; 0);
+
 			if (possible_out > 0) {
 				info->n_outputs.set (DataType::AUDIO, possible_out);
 			} else {
@@ -3046,7 +3052,7 @@ AUPluginInfo::stringify_descriptor (const CAComponentDescription& desc)
 }
 
 bool
-AUPluginInfo::needs_midi_input ()
+AUPluginInfo::needs_midi_input () const
 {
 	return is_effect_with_midi_input () || is_instrument ();
 }

libs/ardour/luaproc.cc

@@ -156,6 +156,7 @@ bool
 LuaProc::load_script ()
 {
 	assert (!_lua_dsp); // don't allow to re-initialize
+	LuaPluginInfoPtr lpi;
 
 	// TODO: refine APIs; function arguments..
 	// - perform channel-map in ardour (silent/scratch buffers) ?
@@ -167,7 +168,7 @@ LuaProc::load_script ()
 
 	try {
 		LuaScriptInfoPtr lsi = LuaScripting::script_info (_script);
-		LuaPluginInfoPtr lpi (new LuaPluginInfo (lsi));
+		lpi = LuaPluginInfoPtr (new LuaPluginInfo (lsi));
 		assert (lpi);
 		set_info (lpi);
 		_mempool.set_name ("LuaProc: " + lsi->name);
@@ -216,6 +217,7 @@ LuaProc::load_script ()
 			;
 		}
 	}
+	lpi->_is_instrument = _has_midi_input;
 
 	_ctrl_params.clear ();
 

libs/ardour/plugin_insert.cc

@@ -341,15 +341,13 @@ PluginInsert::plugin_latency () const {
 }
 
 bool
-PluginInsert::is_midi_instrument() const
+PluginInsert::needs_midi_input() const
 {
-	/* XXX more finesse is possible here. VST plugins have a
-	   a specific "instrument" flag, for example.
-	 */
-	PluginInfoPtr pi = _plugins[0]->get_info();
-
-	return pi->n_inputs.n_midi() != 0 &&
-		pi->n_outputs.n_audio() > 0;
+	PluginInfoPtr pip = _plugins[0]->get_info();
+	if (pip->needs_midi_input ()) {
+		return true;
+	}
+	return pip->n_inputs.n_midi() != 0 && pip->n_outputs.n_audio() != 0;
 }
 
 void
@@ -1535,7 +1533,7 @@ PluginInsert::private_can_support_io_configuration (ChanCount const & inx, ChanC
 		m.strict_io = true;
 
 		/* special case MIDI instruments */
-		if (is_midi_instrument()) {
+		if (needs_midi_input ()) {
 			// output = midi-bypass + at most master-out channels.
 			ChanCount max_out (DataType::AUDIO, 2); // TODO use master-out
 			max_out.set (DataType::MIDI, out.get(DataType::MIDI));