Changed the legato logic

The midistate now counts the active notes instead of it
being per-region

src/sfizz/MidiState.cpp

@@ -14,7 +14,21 @@ void sfz::MidiState::noteOnEvent(int noteNumber, uint8_t velocity) noexcept
     if (noteNumber >= 0 && noteNumber < 128) {
         lastNoteVelocities[noteNumber] = velocity;
         noteOnTimes[noteNumber] = std::chrono::steady_clock::now();
+        activeNotes++;
     }
+
+}
+
+void sfz::MidiState::noteOffEvent(int noteNumber, uint8_t velocity [[maybe_unused]]) noexcept
+{
+    ASSERT(noteNumber >= 0 && noteNumber <= 127);
+    ASSERT(velocity >= 0 && velocity <= 127);
+
+    if (noteNumber >= 0 && noteNumber < 128) {
+        activeNotes--;
+        ASSERT(activeNotes >= 0);
+    }
+
 }
 
 float sfz::MidiState::getNoteDuration(int noteNumber) const
@@ -78,6 +92,7 @@ void sfz::MidiState::reset() noexcept
         ccValue = 0;
 
     pitchBend = 0;
+    activeNotes = 0;
 }
 
 void sfz::MidiState::resetAllControllers() noexcept

src/sfizz/MidiState.h

@@ -23,6 +23,16 @@ public:
      */
 	void noteOnEvent(int noteNumber, uint8_t velocity) noexcept;
 
+    /**
+     * @brief Update the state after a note off event
+     *
+     * @param noteNumber
+     * @param velocity
+     */
+	void noteOffEvent(int noteNumber, uint8_t velocity) noexcept;
+
+    int getActiveNotes() const noexcept { return activeNotes; }
+
     /**
      * @brief Register a note off and get the note duration
      *
@@ -91,6 +101,7 @@ private:
     template<class T>
     using MidiNoteArray = std::array<T, 128>;
     using NoteOnTime = std::chrono::steady_clock::time_point;
+	int activeNotes { 0 };
     /**
      * @brief Stores the note on times.
      *

src/sfizz/Region.cpp

@@ -523,9 +523,6 @@ bool sfz::Region::registerNoteOn(int noteNumber, uint8_t velocity, float randVal
 
     const bool keyOk = keyRange.containsWithEnd(noteNumber);
     if (keyOk) {
-        // Update the number of notes playing for the region
-        activeNotesInRange++;
-
         // Sequence activation
         sequenceCounter += 1;
         if ((sequenceCounter % sequenceLength) == sequencePosition - 1)
@@ -552,9 +549,9 @@ bool sfz::Region::registerNoteOn(int noteNumber, uint8_t velocity, float randVal
 
     const bool velOk = velocityRange.containsWithEnd(velocity);
     const bool randOk = randRange.contains(randValue) || (randValue == 1.0f && randRange.getEnd() == 1.0f);
-    const bool firstLegatoNote = (trigger == SfzTrigger::first && activeNotesInRange == 0);
+    const bool firstLegatoNote = (trigger == SfzTrigger::first && midiState.getActiveNotes() == 1);
     const bool attackTrigger = (trigger == SfzTrigger::attack);
-    const bool notFirstLegatoNote = (trigger == SfzTrigger::legato && activeNotesInRange > 0);
+    const bool notFirstLegatoNote = (trigger == SfzTrigger::legato && midiState.getActiveNotes() > 1);
 
     return keyOk && velOk && randOk && (attackTrigger || firstLegatoNote || notFirstLegatoNote);
 }
@@ -571,10 +568,6 @@ bool sfz::Region::registerNoteOff(int noteNumber, uint8_t velocity [[maybe_unuse
 
     const bool keyOk = keyRange.containsWithEnd(noteNumber);
 
-    // Update the number of notes playing for the region
-    if (keyOk)
-        activeNotesInRange--;
-
     if (!isSwitchedOn())
         return false;
 

src/sfizz/Region.h

@@ -319,7 +319,6 @@ private:
     bool triggerOnCC { false };
     absl::string_view defaultPath { "" };
 
-    int activeNotesInRange { -1 };
     int sequenceCounter { 0 };
 
     std::uniform_real_distribution<float> volumeDistribution { -sfz::Default::ampRandom, sfz::Default::ampRandom };

src/sfizz/Synth.cpp

@@ -417,6 +417,8 @@ void sfz::Synth::noteOff(int delay, int noteNumber, uint8_t velocity [[maybe_unu
     ASSERT(noteNumber < 128);
     ASSERT(noteNumber >= 0);
 
+    midiState.noteOffEvent(noteNumber, velocity);
+
     AtomicGuard callbackGuard { inCallback };
     if (!canEnterCallback)
         return;

tests/RegionTriggersT.cpp

@@ -152,10 +152,15 @@ TEST_CASE("Legato triggers", "Region triggers")
         region.parseOpcode({ "lokey", "40" });
         region.parseOpcode({ "hikey", "50" });
         region.parseOpcode({ "trigger", "first" });
+        midiState.noteOnEvent(40, 64);
         REQUIRE(region.registerNoteOn(40, 64, 0.5f));
+        midiState.noteOnEvent(41, 64);
         REQUIRE(!region.registerNoteOn(41, 64, 0.5f));
+        midiState.noteOffEvent(40, 0);
         region.registerNoteOff(40, 0, 0.5f);
+        midiState.noteOffEvent(41, 0);
         region.registerNoteOff(41, 0, 0.5f);
+        midiState.noteOnEvent(42, 64);
         REQUIRE(region.registerNoteOn(42, 64, 0.5f));
     }
 
@@ -164,10 +169,15 @@ TEST_CASE("Legato triggers", "Region triggers")
         region.parseOpcode({ "lokey", "40" });
         region.parseOpcode({ "hikey", "50" });
         region.parseOpcode({ "trigger", "legato" });
+        midiState.noteOnEvent(40, 64);
         REQUIRE(!region.registerNoteOn(40, 64, 0.5f));
+        midiState.noteOnEvent(41, 64);
         REQUIRE(region.registerNoteOn(41, 64, 0.5f));
+        midiState.noteOffEvent(40, 64);
         region.registerNoteOff(40, 0, 0.5f);
+        midiState.noteOffEvent(41, 64);
         region.registerNoteOff(41, 0, 0.5f);
+        midiState.noteOnEvent(42, 64);
         REQUIRE(!region.registerNoteOn(42, 64, 0.5f));
     }
 }