Always use sample accurate controls

This changes control port buffers to always be sequences of float, splitting
cycles internally so nodes with control ports act as if they support sample
accurate control input and output.  This allows things like having networks of
control ports manipulated by the user which are run into CV ports and having
sample accurate changes end up in the CV ports even though the values were
calculated by plugins with single float ports.

Further work is probably necessary to thin and smooth changes that come from a
user drag (perhaps there should be a mode for this?) to keep the amount of
cycle splitting reasonable, and support for plugins with fixed block length.

8 files changed, 43 insertions, 36 deletions

diff --git a/src/server/ArcImpl.cpp b/src/server/ArcImpl.cpp
index 406d2010..5b96ca03 100644
--- a/src/server/ArcImpl.cpp
+++ b/src/server/ArcImpl.cpp
@@ -67,21 +67,7 @@ ArcImpl::head_path() const
 BufferRef
 ArcImpl::buffer(uint32_t voice, SampleCount offset) const
 {
-	assert(_tail->poly() == 1 || _tail->poly() > voice);
-	if (_tail->poly() == 1) {
-		voice = 0;
-	}
-
-	if (_tail->buffer(0)->is_sequence()) {
-		if (_head->type() == PortType::CONTROL) {
-			_tail->update_values(offset, voice);  // Update value buffer
-			return _tail->value_buffer(voice);  // Return value buffer
-		} else if (_head->type() == PortType::CV) {
-			// Return full tail buffer below
-		}
-	}
-
-	return _tail->buffer(voice);
+	return _tail->buffer(std::min(voice, _tail->poly() - 1));
 }
 
 bool
diff --git a/src/server/BlockImpl.cpp b/src/server/BlockImpl.cpp
index 3b051fd4..d0f0d646 100644
--- a/src/server/BlockImpl.cpp
+++ b/src/server/BlockImpl.cpp
@@ -258,6 +258,17 @@ BlockImpl::process(RunContext& context)
 		// Run the chunk
 		run(subcontext);
 
+		// Emit control port outputs as events
+		for (uint32_t i = 0; _ports && i < _ports->size(); ++i) {
+			PortImpl* const port = _ports->at(i);
+			if (port->type() == PortType::CONTROL && port->is_output()) {
+				// TODO: Only emit events when value has actually changed?
+				for (uint32_t v = 0; v < _polyphony; ++v) {
+					port->buffer(v)->append_event(offset, port->buffer(v)->value());
+				}
+			}
+		}
+
 		offset = chunk_end;
 		subcontext.slice(offset, chunk_end - offset);
 	}
diff --git a/src/server/Buffer.cpp b/src/server/Buffer.cpp
index fb7efa85..2353ab5d 100644
--- a/src/server/Buffer.cpp
+++ b/src/server/Buffer.cpp
@@ -166,12 +166,6 @@ Buffer::copy(const RunContext& context, const Buffer* src)
 		} else {
 			clear();
 		}
-
-		if (_value_buffer && src->_value_buffer) {
-			memcpy(_value_buffer->get<LV2_Atom>(),
-			       src->value(),
-			       lv2_atom_total_size(src->value()));
-		}
 	} else if (src->is_audio() && is_control()) {
 		samples()[0] = src->samples()[0];
 	} else if (src->is_control() && is_audio()) {
@@ -201,6 +195,7 @@ Buffer::port_data(PortType port_type, SampleCount offset)
 {
 	switch (port_type.id()) {
 	case PortType::ID::CONTROL:
+		return &_value_buffer->get<LV2_Atom_Float>()->body;
 	case PortType::ID::CV:
 	case PortType::ID::AUDIO:
 		if (_type == _factory.uris().atom_Float) {
diff --git a/src/server/Buffer.hpp b/src/server/Buffer.hpp
index 939f1f87..bc8ff1aa 100644
--- a/src/server/Buffer.hpp
+++ b/src/server/Buffer.hpp
@@ -115,6 +115,14 @@ public:
 	                      const SampleCount start,
 	                      const SampleCount end)
 	{
+		if (is_sequence()) {
+			append_event(start, sizeof(val), _factory.uris().atom_Float,
+			             reinterpret_cast<const uint8_t*>(
+				             static_cast<const float*>(&val)));
+			_value_buffer->get<LV2_Atom_Float>()->body = val;
+			return;
+		}
+
 		assert(is_audio() || is_control());
 		assert(end <= _capacity / sizeof(Sample));
 		// Note: Do not change this without ensuring GCC can still vectorize it
diff --git a/src/server/InputPort.cpp b/src/server/InputPort.cpp
index fe613f31..cfc43526 100644
--- a/src/server/InputPort.cpp
+++ b/src/server/InputPort.cpp
@@ -210,6 +210,10 @@ InputPort::pre_run(RunContext& context)
 			mix(context, buffer(v).get(), srcs, n_srcs);
 			update_values(context.offset(), v);
 		}
+	} else if (is_a(PortType::CONTROL)) {
+		for (uint32_t v = 0; v < _poly; ++v) {
+			update_values(context.offset(), v);
+		}
 	}
 }
 
diff --git a/src/server/LV2Block.cpp b/src/server/LV2Block.cpp
index 77835b67..e023e3d7 100644
--- a/src/server/LV2Block.cpp
+++ b/src/server/LV2Block.cpp
@@ -117,7 +117,7 @@ LV2Block::make_instance(URIs&      uris,
 
 		if (buffer) {
 			if (port->is_a(PortType::CONTROL)) {
-				buffer->samples()[0] = port->value().get<float>();
+				buffer->set_value(port->value());
 			} else if (port->is_a(PortType::CV)) {
 				buffer->set_block(port->value().get<float>(), 0, engine.block_length());
 			} else {
@@ -267,7 +267,8 @@ LV2Block::instantiate(BufferFactory& bufs, const LilvState* state)
 			}
 			if (port_type == PortType::UNKNOWN) {
 				port_type   = PortType::CONTROL;
-				buffer_type = uris.atom_Float;
+				buffer_type = uris.atom_Sequence;
+				val         = forge.make(def_values[j]);
 			}
 		} else if (lilv_port_is_a(plug, id, uris.lv2_CVPort)) {
 			port_type   = PortType::CV;
diff --git a/src/server/PortImpl.cpp b/src/server/PortImpl.cpp
index 45a5a082..a9c1aefe 100644
--- a/src/server/PortImpl.cpp
+++ b/src/server/PortImpl.cpp
@@ -243,7 +243,7 @@ PortImpl::set_voice_value(const RunContext& context,
 {
 	switch (_type.id()) {
 	case PortType::CONTROL:
-		buffer(voice)->samples()[0] = value;
+		((LV2_Atom_Float*)buffer(voice)->value())->body = value;
 		_voices->at(voice).set_state.set(context, context.start(), value);
 		break;
 	case PortType::AUDIO:
@@ -411,22 +411,24 @@ void
 PortImpl::clear_buffers(const RunContext& ctx)
 {
 	switch (_type.id()) {
-	case PortType::CONTROL:
-	case PortType::CV:
+	case PortType::AUDIO:
+	default:
 		for (uint32_t v = 0; v < _poly; ++v) {
-			Buffer* buf = buffer(v).get();
-			buf->set_block(_value.get<float>(), 0, ctx.nframes());
-			SetState& state = _voices->at(v).set_state;
-			state.state = SetState::State::SET;
-			state.value = _value.get<float>();
-			state.time  = 0;
+			buffer(v)->clear();
 		}
 		break;
-	case PortType::AUDIO:
-	default:
+	case PortType::CONTROL:
 		for (uint32_t v = 0; v < _poly; ++v) {
 			buffer(v)->clear();
+			_voices->at(v).set_state.set(ctx, ctx.start(), _value.get<float>());
+		}
+		break;
+	case PortType::CV:
+		for (uint32_t v = 0; v < _poly; ++v) {
+			buffer(v)->set_block(_value.get<float>(), 0, ctx.nframes());
+			_voices->at(v).set_state.set(ctx, ctx.start(), _value.get<float>());
 		}
+		break;
 	}
 }
 
diff --git a/src/server/events/SetPortValue.cpp b/src/server/events/SetPortValue.cpp
index b8c23605..89c92580 100644
--- a/src/server/events/SetPortValue.cpp
+++ b/src/server/events/SetPortValue.cpp
@@ -56,7 +56,7 @@ SetPortValue::~SetPortValue()
 bool
 SetPortValue::pre_process(PreProcessContext& ctx)
 {
-	Ingen::URIs&  uris = _engine.world()->uris();
+	Ingen::URIs& uris = _engine.world()->uris();
 	if (_port->is_output()) {
 		return Event::pre_process_done(Status::DIRECTION_MISMATCH, _port->path());
 	}
@@ -72,7 +72,7 @@ SetPortValue::pre_process(PreProcessContext& ctx)
 	if (_port->buffer_type() == uris.atom_Sequence) {
 		_buffer = _engine.buffer_factory()->get_buffer(
 			_port->buffer_type(),
-			0,
+			_value.type() == uris.atom_Float ? _value.type() : 0,
 			_engine.buffer_factory()->default_size(_port->buffer_type()));
 	}