prototype lua midi generators & filters and port event-rewrite

6 files changed, 218 insertions, 18 deletions

diff --git a/libs/ardour/luabindings.cc b/libs/ardour/luabindings.cc
index 6c687de56c..23dc0d26f0 100644
--- a/libs/ardour/luabindings.cc
+++ b/libs/ardour/luabindings.cc
@@ -171,6 +171,7 @@ CLASSKEYS(boost::weak_ptr<ARDOUR::Route>);
 CLASSKEYS(std::list<boost::shared_ptr<ARDOUR::Region> >);
 CLASSKEYS(std::list<ARDOUR::AudioRange>);
 CLASSKEYS(Evoral::Beats);
+CLASSKEYS(ARDOUR::PortEngine);
 CLASSKEYS(ARDOUR::PortManager);
 CLASSKEYS(ARDOUR::AudioEngine);
 CLASSKEYS(void);
@@ -459,6 +460,8 @@ LuaBindings::common (lua_State* L)
 		.endClass ()
 
 		.beginWSPtrClass <Port> ("Port")
+		.addCast<MidiPort> ("to_midiport")
+		.addCast<AudioPort> ("to_audioport")
 		.addFunction ("name", &Port::name)
 		.addFunction ("pretty_name", &Port::pretty_name)
 		.addFunction ("receives_input", &Port::receives_input)
@@ -471,6 +474,7 @@ LuaBindings::common (lua_State* L)
 		.addFunction ("connected_to", (bool (Port::*)(Port*)const)&Port::connected_to)
 		.addFunction ("connect", (int (Port::*)(Port*))&Port::connect)
 		.addFunction ("disconnect", (int (Port::*)(Port*))&Port::disconnect)
+		//.addStaticFunction ("port_offset", &Port::port_offset) // static
 		.endClass ()
 
 		.deriveWSPtrClass <AudioPort, Port> ("AudioPort")
@@ -479,6 +483,7 @@ LuaBindings::common (lua_State* L)
 		.deriveWSPtrClass <MidiPort, Port> ("MidiPort")
 		.addFunction ("input_active", &MidiPort::input_active)
 		.addFunction ("set_input_active", &MidiPort::set_input_active)
+		.addFunction ("get_midi_buffer", &MidiPort::get_midi_buffer) // DSP only
 		.endClass ()
 
 		.beginWSPtrClass <PortSet> ("PortSet")
@@ -956,6 +961,9 @@ LuaBindings::common (lua_State* L)
 		.addFunction ("set_output_device_name", &AudioBackend::set_output_device_name)
 		.endClass()
 
+		.beginClass <PortEngine> ("PortEngine")
+		.endClass()
+
 		.beginClass <PortManager> ("PortManager")
 		.addFunction ("port_engine", &PortManager::port_engine)
 		.addFunction ("connected", &PortManager::connected)
@@ -1107,8 +1115,10 @@ LuaBindings::dsp (lua_State* L)
 		.beginClass <MidiBuffer> ("MidiBuffer")
 		.addEqualCheck ()
 		.addFunction ("silence", &MidiBuffer::silence)
-		.addFunction ("empty", &MidiBuffer::empty)
+		.addFunction ("push_event", (bool (MidiBuffer::*)(const Evoral::MIDIEvent<framepos_t>&))&MidiBuffer::push_back)
+		.addFunction ("push_back", (bool (MidiBuffer::*)(framepos_t, size_t, const uint8_t*))&MidiBuffer::push_back)
 		// TODO iterators..
+		.addExtCFunction ("table", &luabridge::CFunc::listToTable<const Evoral::MIDIEvent<framepos_t>, MidiBuffer>)
 		.endClass()
 
 		.beginClass <BufferSet> ("BufferSet")
@@ -1135,8 +1145,8 @@ LuaBindings::dsp (lua_State* L)
 		// add Ctor?
 		.addFunction ("type", &Evoral::MIDIEvent<framepos_t>::type)
 		.addFunction ("channel", &Evoral::MIDIEvent<framepos_t>::channel)
-		.addFunction ("set_type", &Evoral::MIDIEvent<framepos_t>::type)
-		.addFunction ("set_channel", &Evoral::MIDIEvent<framepos_t>::channel)
+		.addFunction ("set_type", &Evoral::MIDIEvent<framepos_t>::set_type)
+		.addFunction ("set_channel", &Evoral::MIDIEvent<framepos_t>::set_channel)
 		.endClass ()
 		.endNamespace ();
 
diff --git a/libs/ardour/luaproc.cc b/libs/ardour/luaproc.cc
index eb67d5c384..fc899ba4ad 100644
--- a/libs/ardour/luaproc.cc
+++ b/libs/ardour/luaproc.cc
@@ -212,15 +212,24 @@ LuaProc::load_script ()
 		}
 	}
 
-	luabridge::LuaRef lua_dsp_midi_in = luabridge::getGlobal (L, "dsp_midi_input");
-	if (lua_dsp_midi_in.type () == LUA_TFUNCTION) {
+	// query midi i/o
+	luabridge::LuaRef lua_dsp_has_midi_in = luabridge::getGlobal (L, "dsp_has_midi_input");
+	if (lua_dsp_has_midi_in.type () == LUA_TFUNCTION) {
 		try {
-			_has_midi_input = lua_dsp_midi_in ();
+			_has_midi_input = lua_dsp_has_midi_in ();
+		} catch (luabridge::LuaException const& e) {
+			;
+		}
+	}
+
+	luabridge::LuaRef lua_dsp_has_midi_out = luabridge::getGlobal (L, "dsp_has_midi_output");
+	if (lua_dsp_has_midi_out.type () == LUA_TFUNCTION) {
+		try {
+			_has_midi_output = lua_dsp_has_midi_out ();
 		} catch (luabridge::LuaException const& e) {
 			;
 		}
 	}
-	lpi->_is_instrument = _has_midi_input;
 
 	_ctrl_params.clear ();
 
@@ -352,10 +361,10 @@ LuaProc::can_support_io_configuration (const ChanCount& in, ChanCount& out, Chan
 	bool found = false;
 	bool exact_match = false;
 	const int32_t audio_in = in.n_audio ();
-	int32_t midi_out = 0; // TODO handle  _has_midi_output
+	int32_t midi_out = _has_midi_output ? 1 : 0;
 
 	// preferred setting (provided by plugin_insert)
-	assert (out.n_audio () > 0);
+	assert (out.n_audio () > 0 || midi_out > 0);
 	const int preferred_out = out.n_audio ();
 
 	for (luabridge::Iterator i (iotable); !i.isNil (); ++i) {
@@ -406,8 +415,17 @@ LuaProc::can_support_io_configuration (const ChanCount& in, ChanCount& out, Chan
 		int possible_out = io["audio_out"];
 
 		if (possible_out == 0) {
+			if (possible_in == 0) {
+				if (_has_midi_output && audio_in == 0) {
+					// special case midi filters & generators
+					audio_out = 0;
+					found = true;
+					break;
+				}
+			}
 			continue;
 		}
+
 		if (possible_in == 0) {
 			/* no inputs, generators & instruments */
 			if (possible_out == -1) {
@@ -527,6 +545,15 @@ LuaProc::can_support_io_configuration (const ChanCount& in, ChanCount& out, Chan
 			int possible_in = io["audio_in"];
 			int possible_out = io["audio_out"];
 
+			if (possible_out == 0 && possible_in == 0 && _has_midi_output) {
+				assert (audio_in > 0); // no input is handled above
+				// TODO hide audio input from plugin
+				imprecise->set (DataType::AUDIO, 0);
+				audio_out = 0;
+				found = true;
+				continue;
+			}
+
 			assert (possible_in > 0); // all other cases will have been matched above
 			assert (possible_out !=0 || possible_in !=0); // already handled above
 
@@ -550,10 +577,10 @@ LuaProc::can_support_io_configuration (const ChanCount& in, ChanCount& out, Chan
 	}
 
 	if (exact_match) {
-		out.set (DataType::MIDI, midi_out); // currently always zero
+		out.set (DataType::MIDI, midi_out);
 		out.set (DataType::AUDIO, preferred_out);
 	} else {
-		out.set (DataType::MIDI, midi_out); // currently always zero
+		out.set (DataType::MIDI, midi_out);
 		out.set (DataType::AUDIO, audio_out);
 	}
 	return true;
@@ -651,7 +678,7 @@ LuaProc::connect_and_run (BufferSet& bufs,
 				}
 			}
 
-			luabridge::LuaRef lua_midi_tbl (luabridge::newTable (L));
+			luabridge::LuaRef lua_midi_src_tbl (luabridge::newTable (L));
 			int e = 1; // > 1 port, we merge events (unsorted)
 			for (uint32_t mp = 0; mp < midi_in; ++mp) {
 				bool valid;
@@ -668,20 +695,52 @@ LuaProc::connect_and_run (BufferSet& bufs,
 						luabridge::LuaRef lua_midi_event (luabridge::newTable (L));
 						lua_midi_event["time"] = 1 + (*m).time();
 						lua_midi_event["data"] = lua_midi_data;
-						lua_midi_tbl[e] = lua_midi_event;
+						lua_midi_src_tbl[e] = lua_midi_event;
 					}
 				}
 			}
 
 			if (_has_midi_input) {
 				// XXX TODO This needs a better solution than global namespace
-				luabridge::push (L, lua_midi_tbl);
-				lua_setglobal (L, "mididata");
+				luabridge::push (L, lua_midi_src_tbl);
+				lua_setglobal (L, "midiin");
 			}
 
+			luabridge::LuaRef lua_midi_sink_tbl (luabridge::newTable (L));
+			if (_has_midi_output) {
+				luabridge::push (L, lua_midi_sink_tbl);
+				lua_setglobal (L, "midiout");
+			}
 
 			// run the DSP function
 			(*_lua_dsp)(in_map, out_map, nframes);
+
+			// copy back midi events
+			if (_has_midi_output && lua_midi_sink_tbl.isTable ()) {
+				bool valid;
+				const uint32_t idx = out.get(DataType::MIDI, 0, &valid);
+				if (valid && bufs.count().n_midi() > idx) {
+					MidiBuffer& mbuf = bufs.get_midi(idx);
+					mbuf.silence(0, 0);
+					for (luabridge::Iterator i (lua_midi_sink_tbl); !i.isNil (); ++i) {
+						if (!i.key ().isNumber ()) { continue; }
+						if (!i.value ()["time"].isNumber ()) { continue; }
+						if (!i.value ()["data"].isTable ()) { continue; }
+						luabridge::LuaRef data_tbl (i.value ()["data"]);
+						framepos_t tme = i.value ()["time"];
+						if (tme < 1 || tme > nframes) { continue; }
+						uint8_t data[64];
+						size_t size = 0;
+						for (luabridge::Iterator di (data_tbl); !di.isNil () && size < sizeof(data); ++di, ++size) {
+							data[size] = di.value ();
+						}
+						if (size > 0 && size < 64) {
+							mbuf.push_back(tme - 1, size, data);
+						}
+					}
+
+				}
+			}
 		}
 	} catch (luabridge::LuaException const& e) {
 		PBD::error << "LuaException: " << e.what () << "\n";
diff --git a/scripts/midi_rewite.lua b/scripts/midi_rewite.lua
new file mode 100644
index 0000000000..35d2e1ddfc
--- /dev/null
+++ b/scripts/midi_rewite.lua
@@ -0,0 +1,36 @@
+ardour {
+	["type"]    = "session",
+	name        = "Rewrite Midi",
+	license     = "MIT",
+	author      = "Robin Gareus",
+	email       = "robin@gareus.org",
+	site        = "http://gareus.org",
+	description = [[An example session script preprocesses midi buffers.]]
+}
+
+function factory ()
+	-- this function is called in every process cycle, before processing
+	return function (n_samples)
+		_, t = Session:engine ():get_ports (ARDOUR.DataType.midi (), ARDOUR.PortList ())
+		for p in t[2]:iter () do
+			if not p:receives_input () then goto next end
+
+			if not p:name () == "MIDI/midi_in 1" then goto next end
+
+			midiport = p:to_midiport ()
+			assert (not midiport:isnil ())
+			mb = midiport:get_midi_buffer (n_samples);
+
+			events = mb:table() -- copy event list into lua table
+			mb:silence (n_samples, 0); -- clear existing buffer
+
+			for _,e in pairs (events) do
+				-- e is an http://ardourman/lua-scripting/class_reference/#Evoral:MidiEvent
+				e:set_channel (2)
+				mb:push_event (e)
+			end
+
+			::next::
+		end
+	end
+end
diff --git a/scripts/midifilter.lua b/scripts/midifilter.lua
new file mode 100644
index 0000000000..ceb115a727
--- /dev/null
+++ b/scripts/midifilter.lua
@@ -0,0 +1,43 @@
+ardour {
+	["type"]    = "dsp",
+	name        = "Midi Filter",
+	category    = "Utility",
+	license     = "MIT",
+	author      = "Robin Gareus",
+	email       = "robin@gareus.org",
+	site        = "http://gareus.org",
+	description = [[An Example Midi Filter for prototyping.]]
+}
+
+function dsp_ioconfig ()
+	return { { audio_in = 0, audio_out = 0}, }
+end
+
+function dsp_has_midi_input () return true end
+function dsp_has_midi_output () return true end
+
+function dsp_run (_, _, n_samples)
+	assert (type(midiin) == "table")
+	assert (type(midiout) == "table")
+	local cnt = 1;
+
+	function tx_midi (time, data)
+		midiout[cnt] = {}
+		midiout[cnt]["time"] = time;
+		midiout[cnt]["data"] = data;
+		cnt = cnt + 1;
+	end
+
+	-- for each incoming midi event
+	for _,b in pairs (midiin) do
+		local t = b["time"] -- t = [ 1 .. n_samples ]
+		local d = b["data"] -- get midi-event
+
+		if (#d == 3 and bit32.band (d[1], 240) == 144) then -- note on
+			tx_midi (t, d)
+		end
+		if (#d == 3 and bit32.band (d[1], 240) == 128) then -- note off
+			tx_midi (t, d)
+		end
+	end
+end
diff --git a/scripts/midigenerator.lua b/scripts/midigenerator.lua
new file mode 100644
index 0000000000..e9aa55d280
--- /dev/null
+++ b/scripts/midigenerator.lua
@@ -0,0 +1,52 @@
+ardour {
+	["type"]    = "dsp",
+	name        = "Midi Generator",
+	category    = "Utility",
+	license     = "MIT",
+	author      = "Robin Gareus",
+	email       = "robin@gareus.org",
+	site        = "http://gareus.org",
+	description = [[An Example Midi Generator for prototyping.]]
+}
+
+function dsp_ioconfig ()
+	return { { audio_in = 0, audio_out = 0}, }
+end
+
+function dsp_has_midi_output () return true end
+
+local tme = 0 -- sample-counter
+local seq = 1 -- sequence-step
+local spb = 0 -- samples per beat
+
+local midi_sequence = {
+	{ 0x90, 64, 127 },
+	{ 0x80, 64,   0 },
+}
+
+function dsp_init (rate)
+	local bpm = 120
+	spb = rate * 60 / bpm
+	if spb < 2 then spb = 2 end
+end
+
+function dsp_run (_, _, n_samples)
+	assert (type(midiout) == "table")
+	assert (spb > 1)
+	local m = 1
+
+	for time = 1,n_samples do -- not very efficient
+		-- TODO, timestamp the sequence in beats, calc/skip to next event
+		tme = tme + 1
+
+		if tme >= spb then
+			midiout[m] = {}
+			midiout[m]["time"] = time
+			midiout[m]["data"] = midi_sequence[seq]
+
+			tme = 0
+			m = m + 1
+			if seq == #midi_sequence then seq = 1 else seq = seq + 1 end
+		end
+	end
+end
diff --git a/scripts/synth1.lua b/scripts/synth1.lua
index 99a5e4d6c8..9d04e29ec1 100644
--- a/scripts/synth1.lua
+++ b/scripts/synth1.lua
@@ -21,7 +21,7 @@ function dsp_ioconfig ()
 	}
 end
 
-function dsp_midi_input ()
+function dsp_has_midi_input ()
 	return true
 end
 
@@ -70,8 +70,8 @@ function dsp_run (ins, outs, n_samples)
 
 	local tme = 1
 	-- parse midi messages
-	assert (type(mididata) == "table") -- global table of midi events (for now)
-	for _,b in pairs (mididata) do 
+	assert (type(midiin) == "table") -- global table of midi events (for now)
+	for _,b in pairs (midiin) do
 		local t = b["time"] -- t = [ 1 .. n_samples ]
 
 		-- synth sound until event