From 34ca6d69e39bc9759d90e250fdb060d436a2398a Mon Sep 17 00:00:00 2001
From: Jean Pierre Cimalando <jp-dev@inbox.ru>
Date: Tue, 23 Feb 2021 09:27:20 +0100
Subject: [PATCH] Display key events on VK, with VST

---
 plugins/editor/src/editor/EditIds.h    | 16 ++++++++
 plugins/editor/src/editor/Editor.cpp   |  8 ++++
 plugins/editor/src/editor/GUIPiano.cpp | 14 +++++++
 plugins/editor/src/editor/GUIPiano.h   |  3 +-
 plugins/vst/SfizzVstController.cpp     | 16 ++++++++
 plugins/vst/SfizzVstController.h       |  1 +
 plugins/vst/SfizzVstEditor.cpp         | 43 ++++++++++++++++++++-
 plugins/vst/SfizzVstEditor.h           |  4 ++
 plugins/vst/SfizzVstProcessor.cpp      | 52 ++++++++++++++++++++++----
 plugins/vst/SfizzVstProcessor.h        |  4 ++
 plugins/vst/SfizzVstUpdates.cpp        | 30 +++++++++++++++
 plugins/vst/SfizzVstUpdates.h          | 27 +++++++++++++
 12 files changed, 207 insertions(+), 11 deletions(-)

diff --git a/plugins/editor/src/editor/EditIds.h b/plugins/editor/src/editor/EditIds.h
index 869d1c44..fd1556bc 100644
--- a/plugins/editor/src/editor/EditIds.h
+++ b/plugins/editor/src/editor/EditIds.h
@@ -22,6 +22,9 @@ enum class EditId : int {
     UserFilesDir,
     FallbackFilesDir,
     //
+    Key0,
+    KeyLast = Key0 + 128 - 1,
+    //
     Controller0,
     ControllerLast = Controller0 + sfz::config::numCCs - 1,
     //
@@ -58,3 +61,16 @@ inline bool editIdIsCC(EditId id)
     return int(id) >= int(EditId::Controller0) &&
         int(id) <= int(EditId::ControllerLast);
 }
+
+inline EditId editIdForKey(int key)
+{
+    return EditId(int(EditId::Key0) + key);
+}
+inline int keyForEditId(EditId id)
+{
+    return int(id) - int(EditId::Key0);
+}
+inline bool editIdIsKey(EditId id)
+{
+    return int(id) >= int(EditId::Key0) && int(id) <= int(EditId::KeyLast);
+}
diff --git a/plugins/editor/src/editor/Editor.cpp b/plugins/editor/src/editor/Editor.cpp
index 173d7166..83507bd6 100644
--- a/plugins/editor/src/editor/Editor.cpp
+++ b/plugins/editor/src/editor/Editor.cpp
@@ -387,6 +387,14 @@ void Editor::Impl::uiReceiveValue(EditId id, const EditValue& v)
             setActivePanel(value);
         }
         break;
+    default:
+        if (editIdIsKey(id)) {
+            const int key = keyForEditId(id);
+            const float value = v.to_float();
+            if (SPiano* piano = piano_)
+                piano->setKeyValue(key, value);
+        }
+        break;
     }
 }
 
diff --git a/plugins/editor/src/editor/GUIPiano.cpp b/plugins/editor/src/editor/GUIPiano.cpp
index 22ec4681..6dc990f1 100644
--- a/plugins/editor/src/editor/GUIPiano.cpp
+++ b/plugins/editor/src/editor/GUIPiano.cpp
@@ -50,6 +50,20 @@ void SPiano::setKeyUsed(unsigned key, bool used)
     invalid();
 }
 
+void SPiano::setKeyValue(unsigned key, float value)
+{
+    if (key >= 128)
+        return;
+
+    value = std::max(0.0f, std::min(1.0f, value));
+
+    if (keyval_[key] == value)
+        return;
+
+    keyval_[key] = value;
+    invalid();
+}
+
 void SPiano::draw(CDrawContext* dc)
 {
     const Dimensions dim = getDimensions(false);
diff --git a/plugins/editor/src/editor/GUIPiano.h b/plugins/editor/src/editor/GUIPiano.h
index c35f8741..eafe115c 100644
--- a/plugins/editor/src/editor/GUIPiano.h
+++ b/plugins/editor/src/editor/GUIPiano.h
@@ -26,6 +26,7 @@ public:
     void setNumOctaves(unsigned octs);
 
     void setKeyUsed(unsigned key, bool used);
+    void setKeyValue(unsigned key, float value);
 
     std::function<void(unsigned, float)> onKeyPressed;
     std::function<void(unsigned, float)> onKeyReleased;
@@ -54,7 +55,7 @@ private:
 
 private:
     unsigned octs_ {};
-    std::vector<unsigned> keyval_;
+    std::vector<float> keyval_;
     std::bitset<128> keyUsed_;
     unsigned mousePressedKey_ = ~0u;
 
diff --git a/plugins/vst/SfizzVstController.cpp b/plugins/vst/SfizzVstController.cpp
index 6717f685..2c3cb320 100644
--- a/plugins/vst/SfizzVstController.cpp
+++ b/plugins/vst/SfizzVstController.cpp
@@ -21,6 +21,7 @@ tresult PLUGIN_API SfizzVstControllerNoUi::initialize(FUnknown* context)
 
     // create update objects
     oscUpdate_ = Steinberg::owned(new OSCUpdate);
+    noteUpdate_ = Steinberg::owned(new NoteUpdate);
     sfzPathUpdate_ = Steinberg::owned(new FilePathUpdate(kFilePathUpdateSfz));
     scalaPathUpdate_ = Steinberg::owned(new FilePathUpdate(kFilePathUpdateScala));
     processorStateUpdate_ = Steinberg::owned(new ProcessorStateUpdate);
@@ -283,6 +284,20 @@ tresult SfizzVstControllerNoUi::notify(Vst::IMessage* message)
         oscUpdate_->changed();
         oscUpdate_->clear();
     }
+    else if (!strcmp(id, "NoteEvents")) {
+        const void* data = nullptr;
+        uint32 size = 0;
+        result = attr->getBinary("Events", data, size);
+
+        const auto* events = reinterpret_cast<
+            const std::pair<uint32_t, float>*>(data);
+        uint32 numEvents = size / sizeof(events[0]);
+
+        // this is a synchronous send, because the update object gets reused
+        noteUpdate_->setEvents(events, numEvents, false);
+        noteUpdate_->changed();
+        noteUpdate_->clear();
+    }
 
     return result;
 }
@@ -307,6 +322,7 @@ IPlugView* PLUGIN_API SfizzVstController::createView(FIDString _name)
 
     std::vector<FObject*> triggerUpdates;
     triggerUpdates.push_back(oscUpdate_);
+    triggerUpdates.push_back(noteUpdate_);
 
     IPtr<SfizzVstEditor> editor = Steinberg::owned(
         new SfizzVstEditor(this, absl::MakeSpan(continuousUpdates), absl::MakeSpan(triggerUpdates)));
diff --git a/plugins/vst/SfizzVstController.h b/plugins/vst/SfizzVstController.h
index 2c207e23..83e94eff 100644
--- a/plugins/vst/SfizzVstController.h
+++ b/plugins/vst/SfizzVstController.h
@@ -46,6 +46,7 @@ public:
 
 protected:
     Steinberg::IPtr<OSCUpdate> oscUpdate_;
+    Steinberg::IPtr<NoteUpdate> noteUpdate_;
     Steinberg::IPtr<FilePathUpdate> sfzPathUpdate_;
     Steinberg::IPtr<FilePathUpdate> scalaPathUpdate_;
     Steinberg::IPtr<ProcessorStateUpdate> processorStateUpdate_;
diff --git a/plugins/vst/SfizzVstEditor.cpp b/plugins/vst/SfizzVstEditor.cpp
index 8345c274..e42721ef 100644
--- a/plugins/vst/SfizzVstEditor.cpp
+++ b/plugins/vst/SfizzVstEditor.cpp
@@ -23,6 +23,7 @@ static ViewRect sfizzUiViewRect { 0, 0, Editor::viewWidth, Editor::viewHeight };
 enum {
     kOscTempSize = 8192,
     kOscQueueSize = 65536,
+    kNoteEventQueueSize = 8192,
 };
 
 SfizzVstEditor::SfizzVstEditor(
@@ -70,6 +71,12 @@ bool PLUGIN_API SfizzVstEditor::open(void* parent, const VSTGUI::PlatformType& p
         oscQueue_.reset(queue);
         queue->reserve(kOscQueueSize);
     }
+    {
+        std::lock_guard<std::mutex> lock(noteEventQueueMutex_);
+        NoteEventsVec* queue = new NoteEventsVec;
+        noteEventQueue_.reset(queue);
+        queue->reserve(kNoteEventQueueSize);
+    }
 
     if (!frame->open(parent, platformType, config)) {
         fprintf(stderr, "[sfizz] error opening frame\n");
@@ -116,8 +123,14 @@ void PLUGIN_API SfizzVstEditor::close()
         this->frame = nullptr;
     }
 
-    std::lock_guard<std::mutex> lock(oscQueueMutex_);
-    oscQueue_.reset();
+    {
+        std::lock_guard<std::mutex> lock(oscQueueMutex_);
+        oscQueue_.reset();
+    }
+    {
+        std::lock_guard<std::mutex> lock(noteEventQueueMutex_);
+        noteEventQueue_.reset();
+    }
 }
 
 ///
@@ -144,6 +157,7 @@ CMessageResult SfizzVstEditor::notify(CBaseObject* sender, const char* message)
 
     if (message == CVSTGUITimer::kMsgTimer) {
         processOscQueue();
+        processNoteEventQueue();
     }
 
     return result;
@@ -163,6 +177,17 @@ void PLUGIN_API SfizzVstEditor::update(FUnknown* changedUnknown, int32 message)
         return;
     }
 
+    if (NoteUpdate* update = FCast<NoteUpdate>(changedUnknown)) {
+        // this update is synchronous: may happen from non-UI thread
+        uint32 count = update->count();
+        if (count > 0) {
+            const auto* events = update->events();
+            std::lock_guard<std::mutex> lock(noteEventQueueMutex_);
+            if (NoteEventsVec* queue = noteEventQueue_.get())
+                std::copy(events, events + count, std::back_inserter(*queue));
+        }
+    }
+
     if (FilePathUpdate* update = FCast<FilePathUpdate>(changedUnknown)) {
         const std::string path = update->getPath();
         switch (update->getType()) {
@@ -259,6 +284,20 @@ void SfizzVstEditor::processOscQueue()
     queue->clear();
 }
 
+void SfizzVstEditor::processNoteEventQueue()
+{
+    std::lock_guard<std::mutex> lock(noteEventQueueMutex_);
+
+    NoteEventsVec* queue = noteEventQueue_.get();
+    if (!queue)
+        return;
+
+    for (std::pair<uint32, float> event : *queue)
+        uiReceiveValue(editIdForKey(event.first), event.second);
+
+    queue->clear();
+}
+
 ///
 void SfizzVstEditor::uiSendValue(EditId id, const EditValue& v)
 {
diff --git a/plugins/vst/SfizzVstEditor.h b/plugins/vst/SfizzVstEditor.h
index a03302a5..79cbb0ee 100644
--- a/plugins/vst/SfizzVstEditor.h
+++ b/plugins/vst/SfizzVstEditor.h
@@ -48,6 +48,7 @@ public:
 
 private:
     void processOscQueue();
+    void processNoteEventQueue();
 
 protected:
     // EditorController
@@ -77,6 +78,9 @@ private:
     typedef std::vector<uint8_t> OscByteVec;
     std::unique_ptr<OscByteVec> oscQueue_;
     std::mutex oscQueueMutex_;
+    typedef std::vector<std::pair<uint32, float>> NoteEventsVec;
+    std::unique_ptr<NoteEventsVec> noteEventQueue_;
+    std::mutex noteEventQueueMutex_;
 
     // subscribed updates
     std::vector<IPtr<FObject>> continuousUpdates_;
diff --git a/plugins/vst/SfizzVstProcessor.cpp b/plugins/vst/SfizzVstProcessor.cpp
index 39b021f3..609de2f8 100644
--- a/plugins/vst/SfizzVstProcessor.cpp
+++ b/plugins/vst/SfizzVstProcessor.cpp
@@ -95,6 +95,8 @@ tresult PLUGIN_API SfizzVstProcessor::initialize(FUnknown* context)
     _synth->timePosition(0, 0, 0);
     _synth->playbackState(0, 0);
 
+    _noteEventsCurrentCycle.fill(-1.0f);
+
     return result;
 }
 
@@ -281,6 +283,21 @@ tresult PLUGIN_API SfizzVstProcessor::process(Vst::ProcessData& data)
             _semaToWorker.post();
     }
 
+    //
+    std::pair<uint32, float> noteEvents[128];
+    size_t numNoteEvents = 0;
+    for (uint32 key = 0; key < 128; ++key) {
+        float value = _noteEventsCurrentCycle[key];
+        if (value < 0.0f)
+            continue;
+        noteEvents[numNoteEvents++] = std::make_pair(key, value);
+        _noteEventsCurrentCycle[key] = -1.0f;
+    }
+    if (numNoteEvents > 0) {
+        if (writeWorkerMessage("NoteEvents", noteEvents, numNoteEvents * sizeof(noteEvents[0])))
+            _semaToWorker.post();
+    }
+
     return kResultTrue;
 }
 
@@ -422,15 +439,28 @@ void SfizzVstProcessor::processEvents(Vst::IEventList& events)
             continue;
 
         switch (e.type) {
-        case Vst::Event::kNoteOnEvent:
-            if (e.noteOn.velocity == 0.0f)
-                synth.noteOff(e.sampleOffset, e.noteOn.pitch, 0);
-            else
-                synth.noteOn(e.sampleOffset, e.noteOn.pitch, convertVelocityFromFloat(e.noteOn.velocity));
+        case Vst::Event::kNoteOnEvent: {
+            int pitch = e.noteOn.pitch;
+            if (pitch < 0 || pitch >= 128)
+                break;
+            if (e.noteOn.velocity <= 0.0f) {
+                synth.noteOff(e.sampleOffset, pitch, 0);
+                _noteEventsCurrentCycle[pitch] = 0.0f;
+            }
+            else {
+                synth.noteOn(e.sampleOffset, pitch, convertVelocityFromFloat(e.noteOn.velocity));
+                _noteEventsCurrentCycle[pitch] = e.noteOn.velocity;
+            }
             break;
-        case Vst::Event::kNoteOffEvent:
-            synth.noteOff(e.sampleOffset, e.noteOff.pitch, convertVelocityFromFloat(e.noteOff.velocity));
+        }
+        case Vst::Event::kNoteOffEvent: {
+            int pitch = e.noteOn.pitch;
+            if (pitch < 0 || pitch >= 128)
+                break;
+            synth.noteOff(e.sampleOffset, pitch, convertVelocityFromFloat(e.noteOff.velocity));
+            _noteEventsCurrentCycle[pitch] = 0.0f;
             break;
+        }
         // case Vst::Event::kPolyPressureEvent:
         //     synth.aftertouch(e.sampleOffset, convertVelocityFromFloat(e.polyPressure.pressure));
         //     break;
@@ -574,7 +604,7 @@ FUnknown* SfizzVstProcessor::createInstance(void*)
 void SfizzVstProcessor::receiveMessage(int delay, const char* path, const char* sig, const sfizz_arg_t* args)
 {
     uint8_t* oscTemp = _oscTemp.get();
-    uint32_t oscSize = sfizz_prepare_message(oscTemp, kOscTempSize, path, sig, args);
+    uint32 oscSize = sfizz_prepare_message(oscTemp, kOscTempSize, path, sig, args);
     if (oscSize <= kOscTempSize) {
         if (writeWorkerMessage("ReceiveMessage", oscTemp, oscSize))
             _semaToWorker.post();
@@ -650,6 +680,12 @@ void SfizzVstProcessor::doBackgroundWork()
             notification->getAttributes()->setBinary("Message", msg->payload<uint8_t>(), msg->size);
             sendMessage(notification);
         }
+        else if (!std::strcmp(id, "NoteEvents")) {
+            Steinberg::OPtr<Vst::IMessage> notification { allocateMessage() };
+            notification->setMessageID("NoteEvents");
+            notification->getAttributes()->setBinary("Events", msg->payload<uint8_t>(), msg->size);
+            sendMessage(notification);
+        }
     }
 }
 
diff --git a/plugins/vst/SfizzVstProcessor.h b/plugins/vst/SfizzVstProcessor.h
index 1401780b..2219ab6a 100644
--- a/plugins/vst/SfizzVstProcessor.h
+++ b/plugins/vst/SfizzVstProcessor.h
@@ -11,6 +11,7 @@
 #include "public.sdk/source/vst/vstaudioeffect.h"
 #include <sfizz.hpp>
 #include <SpinMutex.h>
+#include <array>
 #include <thread>
 #include <memory>
 #include <cstdlib>
@@ -60,6 +61,9 @@ private:
     // misc
     static void loadSfzFileOrDefault(sfz::Sfizz& synth, const std::string& filePath);
 
+    // note event tracking
+    std::array<float, 128> _noteEventsCurrentCycle; // 0: off, >0: on, <0: no change
+
     // worker and thread sync
     std::thread _worker;
     volatile bool _workRunning = false;
diff --git a/plugins/vst/SfizzVstUpdates.cpp b/plugins/vst/SfizzVstUpdates.cpp
index ab6c69f5..d9921bdb 100644
--- a/plugins/vst/SfizzVstUpdates.cpp
+++ b/plugins/vst/SfizzVstUpdates.cpp
@@ -35,3 +35,33 @@ void OSCUpdate::setMessage(const void* data, uint32_t size, bool copy)
     size_ = size;
     allocated_ = copy;
 }
+
+///
+NoteUpdate::~NoteUpdate()
+{
+    clear();
+}
+
+void NoteUpdate::clear()
+{
+    if (allocated_)
+        delete[] events_;
+    events_ = nullptr;
+    count_ = 0;
+    allocated_ = false;
+}
+
+void NoteUpdate::setEvents(const std::pair<uint32_t, float>* events, uint32_t count, bool copy)
+{
+    clear();
+
+    if (copy) {
+        auto *buffer = new std::pair<uint32_t, float>[count];
+        std::memcpy(buffer, events, count);
+        events = buffer;
+    }
+
+    events_ = events;
+    count_ = count;
+    allocated_ = copy;
+}
diff --git a/plugins/vst/SfizzVstUpdates.h b/plugins/vst/SfizzVstUpdates.h
index 0837a047..0fbd8d3a 100644
--- a/plugins/vst/SfizzVstUpdates.h
+++ b/plugins/vst/SfizzVstUpdates.h
@@ -39,6 +39,33 @@ private:
     OSCUpdate& operator=(const OSCUpdate&) = delete;
 };
 
+/**
+ * @brief Update which notifies one or more note on/off events
+ * Is is supposed to be used synchronously.
+ * (ie. FObject::changed or UpdateHandler::triggerUpdates)
+ */
+class NoteUpdate : public Steinberg::FObject {
+public:
+    NoteUpdate() = default;
+    ~NoteUpdate();
+    void clear();
+    void setEvents(const std::pair<uint32_t, float>* events, uint32_t count, bool copy);
+
+    const std::pair<uint32_t, float>* events() const noexcept { return events_; }
+    const uint32_t count() const noexcept { return count_; }
+
+    OBJ_METHODS(NoteUpdate, FObject)
+
+private:
+    const std::pair<uint32_t, float>* events_ = nullptr;
+    uint32_t count_ = 0;
+    bool allocated_ = false;
+
+private:
+    NoteUpdate(const NoteUpdate&) = delete;
+    NoteUpdate& operator=(const NoteUpdate&) = delete;
+};
+
 /**
  * @brief Update which notifies a change of file path pseudo-parameter
  * The message ID is used to indicate which path it is.