MIDI API refactor

driver/main.cpp

@@ -174,6 +174,7 @@ struct AppCallback : boo::IApplicationCallback
     int m_sfxId = -1;
     std::shared_ptr<amuse::Voice> m_vox;
     size_t m_lastVoxCount = 0;
+    int8_t m_lastChanProg = -1;
 
     /* Control state */
     float m_volume = 0.5f;
@@ -297,14 +298,22 @@ struct AppCallback : boo::IApplicationCallback
             m_engine->pumpEngine();
 
             size_t voxCount;
+            int8_t progId;
             if (m_seq)
+            {
                 voxCount = m_seq->getVoiceCount();
+                progId = m_seq->getChanProgram(m_chanId);
+            }
             else
+            {
                 voxCount = 0;
+                progId = -1;
+            }
 
-            if (m_lastVoxCount != voxCount)
+            if (m_lastVoxCount != voxCount || m_lastChanProg != progId)
             {
                 m_lastVoxCount = voxCount;
+                m_lastChanProg = progId;
                 UpdateSongDisplay();
             }
 

include/amuse/BooBackend.hpp

@@ -8,6 +8,9 @@
 #include "IBackendVoice.hpp"
 #include "IBackendSubmix.hpp"
 #include "IBackendVoiceAllocator.hpp"
+#include <mutex>
+#include <list>
+#include <chrono>
 
 namespace amuse
 {
@@ -66,15 +69,21 @@ public:
 /** Backend MIDI event reader for controlling sequencer with external hardware / software */
 class BooBackendMIDIReader : public IMIDIReader, public boo::IMIDIReader
 {
+    friend class BooBackendVoiceAllocator;
     Engine& m_engine;
     std::unique_ptr<boo::IMIDIIn> m_midiIn;
     boo::MIDIDecoder m_decoder;
+
+    std::list<std::pair<std::chrono::steady_clock::time_point, std::vector<uint8_t>>> m_queue;
+    std::mutex m_midiMutex;
+    void _MIDIReceive(std::vector<uint8_t>&& bytes);
+
 public:
-    BooBackendMIDIReader(Engine& engine, std::unique_ptr<boo::IMIDIIn>&& in)
+    ~BooBackendMIDIReader();
-    : m_engine(engine), m_midiIn(std::move(in)), m_decoder(*m_midiIn, *this) {}
+    BooBackendMIDIReader(Engine& engine, const char* name);
 
     std::string description();
-    void pumpReader();
+    void pumpReader(double dt);
 
     void noteOff(uint8_t chan, uint8_t key, uint8_t velocity);
     void noteOn(uint8_t chan, uint8_t key, uint8_t velocity);
@@ -107,6 +116,7 @@ public:
 /** Backend voice allocator implementation for boo mixer */
 class BooBackendVoiceAllocator : public IBackendVoiceAllocator
 {
+    friend class BooBackendMIDIReader;
     boo::IAudioVoiceEngine& m_booEngine;
 public:
     BooBackendVoiceAllocator(boo::IAudioVoiceEngine& booEngine);

include/amuse/Engine.hpp

@@ -26,7 +26,7 @@ class Engine
     friend class Voice;
     friend class Emitter;
     friend class Sequencer;
-    friend class Sequencer::ChannelState;
+    friend struct Sequencer::ChannelState;
 
     IBackendVoiceAllocator& m_backend;
     std::unique_ptr<IMIDIReader> m_midiReader;

include/amuse/IBackendVoiceAllocator.hpp

@@ -29,7 +29,7 @@ class IMIDIReader
 public:
     virtual ~IMIDIReader()=default;
     virtual std::string description()=0;
-    virtual void pumpReader()=0;
+    virtual void pumpReader(double dt)=0;
 };
 
 /** Client-implemented voice allocator */

lib/BooBackend.cpp

@@ -107,9 +107,55 @@ std::string BooBackendMIDIReader::description()
     return m_midiIn->description();
 }
 
-void BooBackendMIDIReader::pumpReader()
+BooBackendMIDIReader::~BooBackendMIDIReader() {}
+
+BooBackendMIDIReader::BooBackendMIDIReader(Engine& engine, const char* name)
+: m_engine(engine), m_decoder(*this)
 {
-    while (m_decoder.receiveBytes()) {}
+    BooBackendVoiceAllocator& voxAlloc = static_cast<BooBackendVoiceAllocator&>(engine.getBackend());
+    if (!name)
+        m_midiIn = voxAlloc.m_booEngine.newVirtualMIDIIn(std::bind(&BooBackendMIDIReader::_MIDIReceive, this,
+                                                                  std::placeholders::_1));
+    else
+        m_midiIn = voxAlloc.m_booEngine.newRealMIDIIn(name,
+                                                     std::bind(&BooBackendMIDIReader::_MIDIReceive, this,
+                                                               std::placeholders::_1));
+}
+
+void BooBackendMIDIReader::_MIDIReceive(std::vector<uint8_t>&& bytes)
+{
+    std::unique_lock<std::mutex> lk(m_midiMutex);
+    m_queue.emplace_back(std::chrono::steady_clock::now(), std::move(bytes));
+}
+
+void BooBackendMIDIReader::pumpReader(double dt)
+{
+    dt += 0.001; /* Add 1ms to ensure consumer keeps up with producer */
+
+    std::unique_lock<std::mutex> lk(m_midiMutex);
+    if (m_queue.empty())
+        return;
+
+    /* Determine range of buffer updates within this period */
+    auto periodEnd = m_queue.cbegin();
+    std::chrono::steady_clock::time_point startPt = m_queue.front().first;
+    for (; periodEnd != m_queue.cend() ; ++periodEnd)
+    {
+        double delta = std::chrono::duration_cast<std::chrono::microseconds>
+                       (periodEnd->first - startPt).count() / 1000000.0;
+        if (delta > dt)
+            break;
+    }
+
+    if (m_queue.cbegin() == periodEnd)
+        return;
+
+    /* Dispatch buffers */
+    for (auto it = m_queue.begin() ; it != periodEnd ;)
+    {
+        m_decoder.receiveBytes(it->second.cbegin(), it->second.cend());
+        it = m_queue.erase(it);
+    }
 }
 
 void BooBackendMIDIReader::noteOff(uint8_t chan, uint8_t key, uint8_t velocity)
@@ -241,16 +287,10 @@ std::vector<std::pair<std::string, std::string>> BooBackendVoiceAllocator::enume
 
 std::unique_ptr<IMIDIReader> BooBackendVoiceAllocator::allocateMIDIReader(Engine& engine, const char* name)
 {
-    std::unique_ptr<boo::IMIDIIn> inPort;
+    std::unique_ptr<IMIDIReader> ret = std::make_unique<BooBackendMIDIReader>(engine, name);
-    if (!name)
+    if (!static_cast<BooBackendMIDIReader&>(*ret).m_midiIn)
-        inPort = m_booEngine.newVirtualMIDIIn();
-    else
-        inPort = m_booEngine.newRealMIDIIn(name);
-
-    if (!inPort)
         return {};
-
+    return ret;
-    return std::make_unique<BooBackendMIDIReader>(engine, std::move(inPort));
 }
 
 void BooBackendVoiceAllocator::register5MsCallback(std::function<void(double)>&& callback)

lib/Engine.cpp

@@ -158,7 +158,7 @@ void Engine::_bringOutYourDead()
 void Engine::_5MsCallback(double dt)
 {
     if (m_midiReader)
-        m_midiReader->pumpReader();
+        m_midiReader->pumpReader(dt);
     for (std::shared_ptr<Sequencer>& seq : m_activeSequencers)
         seq->advance(dt);
 }