Lv2 core implementation

Implementation of the Lv2 core, except for CV ports. No features or
extensions are supported yet.

You can now generate sound using Lv2 instruments (restricted to non-piano)
or effects.

For an explenation about the new classes, see Lv2Manager.h

plugins/LadspaEffect/LadspaControls.h

@@ -71,6 +71,7 @@ private:
 	ch_cnt_t m_controlCount;
 	bool m_noLink;
 	BoolModel m_stereoLinkModel;
+	//! control vector for each processor
 	QVector<control_list_t> m_controls;
 
 

plugins/Lv2Effect/CMakeLists.txt

@@ -0,0 +1,9 @@
+IF(LMMS_HAVE_LV2)
+	INCLUDE_DIRECTORIES(${LV2_INCLUDE_DIRS})
+	INCLUDE_DIRECTORIES(${LILV_INCLUDE_DIRS})
+	INCLUDE_DIRECTORIES(${SUIL_INCLUDE_DIRS})
+	INCLUDE(BuildPlugin)
+	BUILD_PLUGIN(lv2effect Lv2Effect.cpp Lv2FxControls.cpp Lv2FxControlDialog.cpp Lv2Effect.h Lv2FxControls.h Lv2FxControlDialog.h
+		MOCFILES Lv2Effect.h Lv2FxControls.h Lv2FxControlDialog.h
+		EMBEDDED_RESOURCES logo.png)
+ENDIF(LMMS_HAVE_LV2)

plugins/Lv2Effect/Lv2Effect.cpp

@@ -0,0 +1,111 @@
+/*
+ * Lv2Effect.cpp - implementation of LV2 effect
+ *
+ * Copyright (c) 2018-2020 Johannes Lorenz <jlsf2013$users.sourceforge.net, $=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program 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.
+ *
+ * This program 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 more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include "Lv2Effect.h"
+
+#include <QDebug>
+#include <lv2.h>
+
+#include "Lv2SubPluginFeatures.h"
+
+#include "embed.h"
+#include "plugin_export.h"
+
+
+
+
+Plugin::Descriptor PLUGIN_EXPORT lv2effect_plugin_descriptor =
+{
+	STRINGIFY(PLUGIN_NAME),
+	"LV2",
+	QT_TRANSLATE_NOOP("pluginBrowser",
+		"plugin for using arbitrary LV2-effects inside LMMS."),
+	"Johannes Lorenz <jlsf2013$$$users.sourceforge.net, $$$=@>",
+	0x0100,
+	Plugin::Effect,
+	new PluginPixmapLoader("logo"),
+	nullptr,
+	new Lv2SubPluginFeatures(Plugin::Effect)
+};
+
+
+
+
+Lv2Effect::Lv2Effect(Model* parent, const Descriptor::SubPluginFeatures::Key *key) :
+	Effect(&lv2effect_plugin_descriptor, parent, key),
+	m_controls(this, key->attributes["uri"]),
+	m_tmpOutputSmps(Engine::mixer()->framesPerPeriod())
+{
+}
+
+
+
+
+bool Lv2Effect::processAudioBuffer(sampleFrame *buf, const fpp_t frames)
+{
+	if (!isEnabled() || !isRunning()) { return false; }
+	Q_ASSERT(frames <= static_cast<fpp_t>(m_tmpOutputSmps.size()));
+
+	m_controls.copyBuffersFromLmms(buf, frames);
+	m_controls.copyModelsFromLmms();
+
+//	m_pluginMutex.lock();
+	m_controls.run(frames);
+//	m_pluginMutex.unlock();
+
+	m_controls.copyBuffersToLmms(m_tmpOutputSmps.data(), frames);
+
+	double outSum = .0;
+	bool corrupt = wetLevel() < 0; // #3261 - if w < 0, bash w := 0, d := 1
+	const float d = corrupt ? 1 : dryLevel();
+	const float w = corrupt ? 0 : wetLevel();
+	for(fpp_t f = 0; f < frames; ++f)
+	{
+		buf[f][0] = d * buf[f][0] + w * m_tmpOutputSmps[f][0];
+		buf[f][1] = d * buf[f][1] + w * m_tmpOutputSmps[f][1];
+		double l = static_cast<double>(buf[f][0]);
+		double r = static_cast<double>(buf[f][1]);
+		outSum += l*l + r*r;
+	}
+	checkGate(outSum / frames);
+
+	return isRunning();
+}
+
+
+
+
+extern "C"
+{
+
+// necessary for getting instance out of shared lib
+PLUGIN_EXPORT Plugin *lmms_plugin_main(Model *_parent, void *_data)
+{
+	using KeyType = Plugin::Descriptor::SubPluginFeatures::Key;
+	Lv2Effect* eff = new Lv2Effect(_parent, static_cast<const KeyType*>(_data));
+	if (!eff->isValid()) { delete eff; eff = nullptr; }
+	return eff;
+}
+
+}

plugins/Lv2Effect/Lv2Effect.h

@@ -0,0 +1,54 @@
+/*
+ * Lv2Effect.h - implementation of LV2 effect
+ *
+ * Copyright (c) 2018-2020 Johannes Lorenz <jlsf2013$users.sourceforge.net, $=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program 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.
+ *
+ * This program 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 more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef LV2_EFFECT_H
+#define LV2_EFFECT_H
+
+#include "Effect.h"
+#include "Lv2FxControls.h"
+
+class Lv2Effect : public Effect
+{
+	Q_OBJECT
+
+public:
+	/*
+		initialization
+	*/
+	Lv2Effect(Model* parent, const Descriptor::SubPluginFeatures::Key* _key);
+	//! Must be checked after ctor or reload
+	bool isValid() const { return m_controls.isValid(); }
+
+	bool processAudioBuffer( sampleFrame* buf, const fpp_t frames ) override;
+	EffectControls* controls() override { return &m_controls; }
+
+	Lv2FxControls* lv2Controls() { return &m_controls; }
+	const Lv2FxControls* lv2Controls() const { return &m_controls; }
+
+private:
+	Lv2FxControls m_controls;
+	std::vector<sampleFrame> m_tmpOutputSmps;
+};
+
+#endif // LMMS_HAVE_LV2

plugins/Lv2Effect/Lv2FxControlDialog.cpp

@@ -0,0 +1,72 @@
+/*
+ * Lv2FxControlDialog.cpp - Lv2FxControlDialog implementation
+ *
+ * Copyright (c) 2018-2020 Johannes Lorenz <jlsf2013$users.sourceforge.net, $=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program 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.
+ *
+ * This program 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 more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include "Lv2FxControlDialog.h"
+
+#include <QDebug>
+#include <QPushButton>
+#include <lv2.h>
+
+#include "Lv2Effect.h"
+#include "Lv2FxControls.h"
+
+
+Lv2FxControlDialog::Lv2FxControlDialog(Lv2FxControls *controls) :
+	EffectControlDialog(controls),
+	Lv2ViewBase(this, controls)
+{
+	if (m_reloadPluginButton) {
+		connect(m_reloadPluginButton, &QPushButton::clicked,
+				this, [this](){ lv2Controls()->reloadPlugin(); });
+	}
+	if (m_toggleUIButton) {
+		connect(m_toggleUIButton, &QPushButton::toggled,
+			this, [this](){ toggleUI(); });
+	}
+	if (m_helpButton) {
+		connect(m_helpButton, &QPushButton::toggled,
+			this, [this](bool visible){ toggleHelp(visible); });
+	}
+	// for Effects, modelChanged only goes to the top EffectView
+	// we need to call it manually
+	modelChanged();
+}
+
+
+
+
+Lv2FxControls *Lv2FxControlDialog::lv2Controls()
+{
+	return static_cast<Lv2FxControls *>(m_effectControls);
+}
+
+
+
+
+void Lv2FxControlDialog::modelChanged()
+{
+	Lv2ViewBase::modelChanged(lv2Controls());
+}
+
+

plugins/Lv2Effect/Lv2FxControlDialog.h

@@ -0,0 +1,47 @@
+/*
+ * Lv2FxControlDialog.h - Lv2FxControlDialog implementation
+ *
+ * Copyright (c) 2018-2020 Johannes Lorenz <jlsf2013$users.sourceforge.net, $=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program 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.
+ *
+ * This program 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 more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef LV2_FX_CONTROL_DIALOG_H
+#define LV2_FX_CONTROL_DIALOG_H
+
+#include "EffectControlDialog.h"
+#include "Lv2ViewBase.h"
+
+class Lv2FxControls;
+
+
+class Lv2FxControlDialog : public EffectControlDialog, public Lv2ViewBase
+{
+	Q_OBJECT
+
+public:
+	Lv2FxControlDialog(Lv2FxControls *controls);
+
+private:
+	Lv2FxControls *lv2Controls();
+	void modelChanged() override;
+};
+
+
+#endif

plugins/Lv2Effect/Lv2FxControls.cpp

@@ -0,0 +1,104 @@
+/*
+ * Lv2FxControls.cpp - Lv2FxControls implementation
+ *
+ * Copyright (c) 2018-2020 Johannes Lorenz <jlsf2013$users.sourceforge.net, $=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program 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.
+ *
+ * This program 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 more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include "Lv2FxControls.h"
+
+#include <QDomElement>
+
+#include "Engine.h"
+#include "Lv2Effect.h"
+#include "Lv2FxControlDialog.h"
+#include "Lv2Proc.h"
+
+
+
+
+Lv2FxControls::Lv2FxControls(class Lv2Effect *effect, const QString& uri) :
+	EffectControls(effect),
+	Lv2ControlBase(this, uri)
+{
+	if (isValid())
+	{
+		connect(Engine::mixer(), &Mixer::sampleRateChanged,
+			this, [this](){Lv2ControlBase::reloadPlugin();});
+	}
+}
+
+
+
+
+void Lv2FxControls::saveSettings(QDomDocument &doc, QDomElement &that)
+{
+	Lv2ControlBase::saveSettings(doc, that);
+}
+
+
+
+
+void Lv2FxControls::loadSettings(const QDomElement &that)
+{
+	Lv2ControlBase::loadSettings(that);
+}
+
+
+
+
+int Lv2FxControls::controlCount()
+{
+	return static_cast<int>(Lv2ControlBase::controlCount());
+}
+
+
+
+
+EffectControlDialog *Lv2FxControls::createView()
+{
+	return new Lv2FxControlDialog(this);
+}
+
+
+
+
+void Lv2FxControls::changeControl() // TODO: what is that?
+{
+	//	engine::getSong()->setModified();
+}
+
+
+
+
+DataFile::Types Lv2FxControls::settingsType()
+{
+	return DataFile::EffectSettings;
+}
+
+
+
+
+void Lv2FxControls::setNameFromFile(const QString &name)
+{
+	effect()->setDisplayName(name);
+}
+
+

plugins/Lv2Effect/Lv2FxControls.h

@@ -0,0 +1,61 @@
+/*
+ * Lv2FxControls.h - Lv2FxControls implementation
+ *
+ * Copyright (c) 2018-2020 Johannes Lorenz <jlsf2013$users.sourceforge.net, $=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program 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.
+ *
+ * This program 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 more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef LV2_FX_CONTROLS_H
+#define LV2_FX_CONTROLS_H
+
+#include "EffectControls.h"
+#include "Lv2ControlBase.h"
+
+class Lv2Effect;
+
+
+class Lv2FxControls : public EffectControls, public Lv2ControlBase
+{
+	Q_OBJECT
+public:
+	Lv2FxControls(Lv2Effect *effect, const QString &uri);
+
+	void saveSettings(QDomDocument &_doc, QDomElement &_parent) override;
+	void loadSettings(const QDomElement &that) override;
+	inline QString nodeName() const override
+	{
+		return Lv2ControlBase::nodeName();
+	}
+
+	int controlCount() override;
+	EffectControlDialog *createView() override;
+
+private slots:
+	void changeControl();
+
+private:
+	DataFile::Types settingsType() override;
+	void setNameFromFile(const QString &name) override;
+
+	friend class Lv2FxControlDialog;
+	friend class Lv2Effect;
+};
+
+#endif

plugins/Lv2Instrument/CMakeLists.txt

@@ -0,0 +1,7 @@
+IF(LMMS_HAVE_LV2)
+	INCLUDE_DIRECTORIES(${LV2_INCLUDE_DIRS})
+	INCLUDE_DIRECTORIES(${LILV_INCLUDE_DIRS})
+	INCLUDE_DIRECTORIES(${SUIL_INCLUDE_DIRS})
+	INCLUDE(BuildPlugin)
+	BUILD_PLUGIN(lv2instrument Lv2Instrument.cpp Lv2Instrument.h MOCFILES Lv2Instrument.h EMBEDDED_RESOURCES logo.png)
+ENDIF(LMMS_HAVE_LV2)

plugins/Lv2Instrument/Lv2Instrument.cpp

@@ -0,0 +1,303 @@
+/*
+ * Lv2Instrument.cpp - implementation of LV2 instrument
+ *
+ * Copyright (c) 2018-2020 Johannes Lorenz <jlsf2013$users.sourceforge.net, $=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program 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.
+ *
+ * This program 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 more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include "Lv2Instrument.h"
+
+#include <QDebug>
+#include <QDragEnterEvent>
+
+#include "Engine.h"
+#include "InstrumentPlayHandle.h"
+#include "InstrumentTrack.h"
+#include "Lv2SubPluginFeatures.h"
+#include "Mixer.h"
+#include "StringPairDrag.h"
+
+#include "embed.h"
+#include "plugin_export.h"
+
+
+
+
+Plugin::Descriptor PLUGIN_EXPORT lv2instrument_plugin_descriptor =
+{
+	STRINGIFY(PLUGIN_NAME),
+	"LV2",
+	QT_TRANSLATE_NOOP("pluginBrowser",
+		"plugin for using arbitrary LV2 instruments inside LMMS."),
+	"Johannes Lorenz <jlsf2013$$$users.sourceforge.net, $$$=@>",
+	0x0100,
+	Plugin::Instrument,
+	new PluginPixmapLoader("logo"),
+	nullptr,
+	new Lv2SubPluginFeatures(Plugin::Instrument)
+};
+
+
+
+
+/*
+	Lv2Instrument
+*/
+
+
+Lv2Instrument::Lv2Instrument(InstrumentTrack *instrumentTrackArg,
+	Descriptor::SubPluginFeatures::Key *key) :
+	Instrument(instrumentTrackArg, &lv2instrument_plugin_descriptor, key),
+	Lv2ControlBase(this, key->attributes["uri"])
+{
+	if (Lv2ControlBase::isValid())
+	{
+#ifdef LV2_INSTRUMENT_USE_MIDI
+		for (int i = 0; i < NumKeys; ++i) { m_runningNotes[i] = 0; }
+#endif
+		connect(instrumentTrack()->pitchRangeModel(), SIGNAL(dataChanged()),
+			this, SLOT(updatePitchRange()), Qt::DirectConnection);
+		connect(Engine::mixer(), &Mixer::sampleRateChanged,
+			this, [this](){Lv2ControlBase::reloadPlugin();});
+
+		// now we need a play-handle which cares for calling play()
+		InstrumentPlayHandle *iph =
+			new InstrumentPlayHandle(this, instrumentTrackArg);
+		Engine::mixer()->addPlayHandle(iph);
+	}
+}
+
+
+
+
+Lv2Instrument::~Lv2Instrument()
+{
+	Engine::mixer()->removePlayHandlesOfTypes(instrumentTrack(),
+		PlayHandle::TypeNotePlayHandle |
+						  PlayHandle::TypeInstrumentPlayHandle);
+}
+
+
+
+
+bool Lv2Instrument::isValid() const { return Lv2ControlBase::isValid(); }
+
+
+
+
+void Lv2Instrument::saveSettings(QDomDocument &doc, QDomElement &that)
+{
+	Lv2ControlBase::saveSettings(doc, that);
+}
+
+
+
+
+void Lv2Instrument::loadSettings(const QDomElement &that)
+{
+	Lv2ControlBase::loadSettings(that);
+}
+
+
+
+
+void Lv2Instrument::loadFile(const QString &file)
+{
+	Lv2ControlBase::loadFile(file);
+}
+
+
+
+
+#ifdef LV2_INSTRUMENT_USE_MIDI
+bool Lv2Instrument::handleMidiEvent(
+	const MidiEvent &event, const MidiTime &time, f_cnt_t offset)
+{
+	// this function can be called from GUI threads while the plugin is running,
+	// so this requires caching, e.g. in ringbuffers
+	(void)time;
+	(void)offset;
+	(void)event;
+	return true;
+}
+#endif
+
+
+
+
+// not yet working
+#ifndef LV2_INSTRUMENT_USE_MIDI
+void Lv2Instrument::playNote(NotePlayHandle *nph, sampleFrame *)
+{
+}
+#endif
+
+
+
+
+void Lv2Instrument::play(sampleFrame *buf)
+{
+	copyModelsFromLmms();
+
+	fpp_t fpp = Engine::mixer()->framesPerPeriod();
+
+	run(fpp);
+
+	copyBuffersToLmms(buf, fpp);
+
+	instrumentTrack()->processAudioBuffer(buf, fpp, nullptr);
+}
+
+
+
+
+PluginView *Lv2Instrument::instantiateView(QWidget *parent)
+{
+	return new Lv2InsView(this, parent);
+}
+
+
+
+
+void Lv2Instrument::updatePitchRange()
+{
+	qDebug() << "Lmms: Cannot update pitch range for lv2 plugin:"
+				"not implemented yet";
+}
+
+
+
+
+QString Lv2Instrument::nodeName() const
+{
+	return Lv2ControlBase::nodeName();
+}
+
+
+
+
+DataFile::Types Lv2Instrument::settingsType()
+{
+	return DataFile::InstrumentTrackSettings;
+}
+
+
+
+
+void Lv2Instrument::setNameFromFile(const QString &name)
+{
+	instrumentTrack()->setName(name);
+}
+
+
+
+
+/*
+	Lv2InsView
+*/
+
+
+Lv2InsView::Lv2InsView(Lv2Instrument *_instrument, QWidget *_parent) :
+	InstrumentView(_instrument, _parent),
+	Lv2ViewBase(this, _instrument)
+{
+	setAutoFillBackground(true);
+	if (m_reloadPluginButton) {
+		connect(m_reloadPluginButton, &QPushButton::clicked,
+			this, [this](){ castModel<Lv2Instrument>()->reloadPlugin();} );
+	}
+	if (m_toggleUIButton) {
+		connect(m_toggleUIButton, &QPushButton::toggled,
+			this, [this](){ toggleUI(); });
+	}
+	if (m_helpButton) {
+		connect(m_helpButton, &QPushButton::toggled,
+			this, [this](bool visible){ toggleHelp(visible); });
+	}
+}
+
+
+
+
+void Lv2InsView::dragEnterEvent(QDragEnterEvent *_dee)
+{
+	void (QDragEnterEvent::*reaction)(void) = &QDragEnterEvent::ignore;
+
+	if (_dee->mimeData()->hasFormat(StringPairDrag::mimeType()))
+	{
+		const QString txt =
+			_dee->mimeData()->data(StringPairDrag::mimeType());
+		if (txt.section(':', 0, 0) == "pluginpresetfile") {
+			reaction = &QDragEnterEvent::acceptProposedAction;
+		}
+	}
+
+	(_dee->*reaction)();
+}
+
+
+
+
+void Lv2InsView::dropEvent(QDropEvent *_de)
+{
+	const QString type = StringPairDrag::decodeKey(_de);
+	const QString value = StringPairDrag::decodeValue(_de);
+	if (type == "pluginpresetfile")
+	{
+		castModel<Lv2Instrument>()->loadFile(value);
+		_de->accept();
+		return;
+	}
+	_de->ignore();
+}
+
+
+
+
+void Lv2InsView::toggleUI()
+{
+}
+
+
+
+
+void Lv2InsView::modelChanged()
+{
+	Lv2ViewBase::modelChanged(castModel<Lv2Instrument>());
+}
+
+
+
+
+extern "C"
+{
+
+// necessary for getting instance out of shared lib
+PLUGIN_EXPORT Plugin *lmms_plugin_main(Model *_parent, void *_data)
+{
+	using KeyType = Plugin::Descriptor::SubPluginFeatures::Key;
+	Lv2Instrument* ins = new Lv2Instrument(
+							static_cast<InstrumentTrack*>(_parent),
+							static_cast<KeyType*>(_data ));
+	if (!ins->isValid()) { delete ins; ins = nullptr; }
+	return ins;
+}
+
+}

plugins/Lv2Instrument/Lv2Instrument.h

@@ -0,0 +1,123 @@
+/*
+ * Lv2Instrument.h - implementation of LV2 instrument
+ *
+ * Copyright (c) 2018-2020 Johannes Lorenz <jlsf2013$users.sourceforge.net, $=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program 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.
+ *
+ * This program 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 more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef LV2_INSTRUMENT_H
+#define LV2_INSTRUMENT_H
+
+#include <QString>
+
+#include "Instrument.h"
+#include "InstrumentView.h"
+#include "Note.h"
+#include "Lv2ControlBase.h"
+#include "Lv2ViewBase.h"
+
+// whether to use MIDI vs playHandle
+// currently only MIDI works
+#define LV2_INSTRUMENT_USE_MIDI
+
+class QPushButton;
+
+
+class Lv2Instrument : public Instrument, public Lv2ControlBase
+{
+	Q_OBJECT
+public:
+	/*
+		initialization
+	*/
+	Lv2Instrument(InstrumentTrack *instrumentTrackArg,
+		 Descriptor::SubPluginFeatures::Key* key);
+	~Lv2Instrument() override;
+	//! Must be checked after ctor or reload
+	bool isValid() const;
+
+	/*
+		load/save
+	*/
+	void saveSettings(QDomDocument &doc, QDomElement &that) override;
+	void loadSettings(const QDomElement &that) override;
+	void loadFile(const QString &file) override;
+
+	/*
+		realtime funcs
+	*/
+	bool hasNoteInput() const override { return false; /* not supported yet */ }
+#ifdef LV2_INSTRUMENT_USE_MIDI
+	bool handleMidiEvent(const MidiEvent &event,
+		const MidiTime &time = MidiTime(), f_cnt_t offset = 0) override;
+#else
+	void playNote(NotePlayHandle *nph, sampleFrame *) override;
+#endif
+	void play(sampleFrame *buf) override;
+
+	/*
+		misc
+	*/
+	Flags flags() const override
+	{
+#ifdef LV2_INSTRUMENT_USE_MIDI
+		return IsSingleStreamed | IsMidiBased;
+#else
+		return IsSingleStreamed;
+#endif
+	}
+	PluginView *instantiateView(QWidget *parent) override;
+
+private slots:
+	void updatePitchRange();
+
+private:
+	QString nodeName() const override;
+	DataFile::Types settingsType() override;
+	void setNameFromFile(const QString &name) override;
+
+#ifdef LV2_INSTRUMENT_USE_MIDI
+	int m_runningNotes[NumKeys];
+#endif
+
+	friend class Lv2InsView;
+};
+
+
+class Lv2InsView : public InstrumentView, public Lv2ViewBase
+{
+	Q_OBJECT
+public:
+	Lv2InsView(Lv2Instrument *_instrument, QWidget *_parent);
+
+protected:
+	void dragEnterEvent(QDragEnterEvent *_dee) override;
+	void dropEvent(QDropEvent *_de) override;
+
+private slots:
+	void reloadPlugin();
+	void toggleUI();
+
+private:
+	void modelChanged() override;
+};
+
+
+#endif // LV2_INSTRUMENT_H