From 87c3cfacedd49676e94b549d0f05b30d74c04e24 Mon Sep 17 00:00:00 2001
From: Paul Ferrand <paul@ferrand.cc>
Date: Tue, 18 Feb 2020 14:44:48 +0100
Subject: [PATCH] The voice state matches its envelope release state

---
 src/sfizz/ADSREnvelope.cpp | 13 +++++++++++--
 src/sfizz/ADSREnvelope.h   |  9 ++++++++-
 src/sfizz/Voice.cpp        | 13 ++-----------
 3 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/src/sfizz/ADSREnvelope.cpp b/src/sfizz/ADSREnvelope.cpp
index d5aa2c87..c1fad38e 100644
--- a/src/sfizz/ADSREnvelope.cpp
+++ b/src/sfizz/ADSREnvelope.cpp
@@ -205,9 +205,15 @@ void ADSREnvelope<Type>::getBlock(absl::Span<Type> output) noexcept
     }
 }
 template <class Type>
-bool ADSREnvelope<Type>::isSmoothing() noexcept
+bool ADSREnvelope<Type>::isSmoothing() const noexcept
 {
-    return currentState != State::Done;
+    return (currentState != State::Done);
+}
+
+template <class Type>
+bool ADSREnvelope<Type>::isReleased() const noexcept
+{
+    return (currentState == State::Release);
 }
 
 template <class Type>
@@ -222,6 +228,9 @@ void ADSREnvelope<Type>::startRelease(int releaseDelay, bool fastRelease) noexce
     shouldRelease = true;
     this->releaseDelay = releaseDelay;
 
+    if (releaseDelay == 0)
+        currentState = State::Release;
+
     if (fastRelease)
         this->release = 0;
 }
diff --git a/src/sfizz/ADSREnvelope.h b/src/sfizz/ADSREnvelope.h
index afa45f91..f2468a09 100644
--- a/src/sfizz/ADSREnvelope.h
+++ b/src/sfizz/ADSREnvelope.h
@@ -58,7 +58,14 @@ public:
      * @return true
      * @return false
      */
-    bool isSmoothing() noexcept;
+    bool isSmoothing() const noexcept;
+    /**
+     * @brief Is the envelope released?
+     *
+     * @return true
+     * @return false
+     */
+    bool isReleased() const noexcept;
     /**
      * @brief Get the remaining delay samples
      *
diff --git a/src/sfizz/Voice.cpp b/src/sfizz/Voice.cpp
index 95d854c5..0ec124ee 100644
--- a/src/sfizz/Voice.cpp
+++ b/src/sfizz/Voice.cpp
@@ -125,7 +125,6 @@ void sfz::Voice::release(int delay, bool fastRelease) noexcept
     if (egEnvelope.getRemainingDelay() > std::max(0, delay - initialDelay)) {
         reset();
     } else {
-        state = State::release;
         egEnvelope.startRelease(delay, fastRelease);
     }
 }
@@ -382,8 +381,6 @@ void sfz::Voice::fillWithData(AudioSpan<float> buffer) noexcept
     sfzInterpolationCast<float>(jumps, indices, leftCoeffs, rightCoeffs);
     add<int>(sourcePosition, indices);
 
-    absl::optional<int> releaseAt {};
-
     if (region->shouldLoop() && region->loopEnd(currentPromise->oversamplingFactor) <= source.getNumFrames()) {
         const auto loopEnd = static_cast<int>(region->loopEnd(currentPromise->oversamplingFactor));
         const auto offset = loopEnd - static_cast<int>(region->loopStart(currentPromise->oversamplingFactor)) + 1;
@@ -400,7 +397,7 @@ void sfz::Voice::fillWithData(AudioSpan<float> buffer) noexcept
         ) - 2;
         for (auto* index = indices.begin(); index < indices.end(); ++index) {
             if (*index >= sampleEnd) {
-                releaseAt = static_cast<int>(std::distance(indices.begin(), index));
+                release(static_cast<int>(std::distance(indices.begin(), index)));
                 const auto remainingElements = static_cast<size_t>(std::distance(index, indices.end()));
                 if (source.getNumFrames() - 1 < region->trueSampleEnd(currentPromise->oversamplingFactor)) {
                     DBG("[sfizz] Underflow: source available samples "
@@ -438,12 +435,6 @@ void sfz::Voice::fillWithData(AudioSpan<float> buffer) noexcept
 
     sourcePosition = indices.back();
     floatPositionOffset = rightCoeffs.back();
-
-    if (state != State::release && releaseAt) {
-        release(*releaseAt);
-        // TODO: not needed probably
-        buffer.subspan(*releaseAt).fill(0.0f);
-    }
 }
 
 void sfz::Voice::fillWithGenerator(AudioSpan<float> buffer) noexcept
@@ -535,7 +526,7 @@ float sfz::Voice::getMeanSquaredAverage() const noexcept
 
 bool sfz::Voice::canBeStolen() const noexcept
 {
-    return state == State::release;
+    return state == State::idle || egEnvelope.isReleased();
 }
 
 uint32_t sfz::Voice::getSourcePosition() const noexcept