From 5139c648f0dab00c3b9c600bbe5091e460436efa Mon Sep 17 00:00:00 2001
From: Paul Ferrand <paul@ferrand.cc>
Date: Tue, 25 Aug 2020 19:31:47 +0200
Subject: [PATCH] Engine polyphony is checked in findFreeVoice()

---
 src/sfizz/Synth.cpp | 29 ++++++++++++-----------------
 src/sfizz/Synth.h   |  5 ++++-
 2 files changed, 16 insertions(+), 18 deletions(-)

diff --git a/src/sfizz/Synth.cpp b/src/sfizz/Synth.cpp
index e6da53ad..09fa9736 100644
--- a/src/sfizz/Synth.cpp
+++ b/src/sfizz/Synth.cpp
@@ -659,7 +659,18 @@ sfz::Voice* sfz::Synth::findFreeVoice() noexcept
     if (freeVoice != voices.end())
         return freeVoice->get();
 
-    return {};
+    // Engine polyphony reached
+    Voice* stolenVoice = stealer.steal(absl::MakeSpan(voiceViewArray));
+    if (stolenVoice == nullptr)
+        return {};
+
+    auto tempSpan = resources.bufferPool.getStereoBuffer(samplesPerBlock);
+    SisterVoiceRing::applyToRing(stolenVoice, [&] (Voice* v) {
+        renderVoiceToOutputs(*v, *tempSpan);
+        v->reset();
+    });
+
+    return stolenVoice;
 }
 
 int sfz::Synth::getNumActiveVoices(bool recompute) const noexcept
@@ -997,27 +1008,11 @@ void sfz::Synth::noteOnDispatch(int delay, int noteNumber, float velocity) noexc
             }
 
             Voice* selectedVoice = findFreeVoice();
-
-            // Engine polyphony reached, we're stealing something
-            if (selectedVoice == nullptr) {
-                selectedVoice = stealer.steal(absl::MakeSpan(voiceViewArray));
-            }
-
             // For some reason we did not find a voice to use.
             // This is a degraded case but we'll just drop the note on.
             if (selectedVoice == nullptr)
                 continue;
 
-            // Kill voice if necessary, pre-rendering it into the output buffers
-            if (!selectedVoice->isFree()) {
-                auto tempSpan = resources.bufferPool.getStereoBuffer(samplesPerBlock);
-                SisterVoiceRing::applyToRing(selectedVoice, [&] (Voice* v) {
-                    renderVoiceToOutputs(*v, *tempSpan);
-                    v->reset();
-                });
-            }
-
-            // Voice should be free now
             ASSERT(selectedVoice->isFree());
             selectedVoice->startVoice(region, delay, noteNumber, velocity, Voice::TriggerType::NoteOn);
             ring.addVoiceToRing(selectedVoice);
diff --git a/src/sfizz/Synth.h b/src/sfizz/Synth.h
index 3fb85f7f..7dd3b0ad 100644
--- a/src/sfizz/Synth.h
+++ b/src/sfizz/Synth.h
@@ -765,18 +765,21 @@ private:
     using RegionSetPtr = std::unique_ptr<RegionSet>;
     std::vector<RegionPtr> regions;
     std::vector<VoicePtr> voices;
+
     // These are more general "groups" than sfz and encapsulates the full hierarchy
     RegionSet* currentSet;
     OpcodeScope lastHeader { OpcodeScope::kOpcodeScopeGlobal };
     std::vector<RegionSetPtr> sets;
+
     // These are the `group=` groups where you can off voices
     std::vector<PolyphonyGroup> polyphonyGroups;
+
     // Views to speed up iteration over the regions and voices when events
     // occur in the audio callback
     VoiceViewVector regionPolyphonyArray;
+    VoiceViewVector voiceViewArray;
     VoiceStealing stealer;
 
-    VoiceViewVector voiceViewArray;
     std::array<RegionViewVector, 128> noteActivationLists;
     std::array<RegionViewVector, config::numCCs> ccActivationLists;