From 6c2f5b5ecb59dd5d6a48b9d4a89e5d87f20f6720 Mon Sep 17 00:00:00 2001
From: Paul Ferrand <paul@ferrand.cc>
Date: Tue, 17 Dec 2019 21:12:11 +0100
Subject: [PATCH] Corrected the multiplicative envelope logic The previous
 version alternatively cleared or ignored messages every other block

---
 src/sfizz/EventEnvelopes.cpp | 21 ++++++++++++---------
 tests/EventEnvelopesT.cpp    | 19 +++++++++++++++++++
 2 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/src/sfizz/EventEnvelopes.cpp b/src/sfizz/EventEnvelopes.cpp
index 8887fd33..1128eba6 100644
--- a/src/sfizz/EventEnvelopes.cpp
+++ b/src/sfizz/EventEnvelopes.cpp
@@ -57,7 +57,9 @@ void EventEnvelope<Type>::setFunction(std::function<Type(Type)> function)
 template <class Type>
 void EventEnvelope<Type>::registerEvent(int timestamp, Type inputValue)
 {
-    
+    if (resetEvents)
+        clear();
+
     if (static_cast<int>(events.size()) < maxCapacity)
         events.emplace_back(timestamp, function(inputValue));
 }
@@ -65,14 +67,14 @@ void EventEnvelope<Type>::registerEvent(int timestamp, Type inputValue)
 template <class Type>
 void EventEnvelope<Type>::prepareEvents()
 {
-    if (resetEvents) {
+    if (resetEvents)
         clear();
-    } else {
-        absl::c_sort(events, [](const auto& lhs, const auto& rhs) {
-            return lhs.first < rhs.first;
-        });
-        resetEvents = true;
-    }
+
+    absl::c_sort(events, [](const auto& lhs, const auto& rhs) {
+        return lhs.first < rhs.first;
+    });
+    
+    resetEvents = true;
 }
 
 template <class Type>
@@ -201,7 +203,8 @@ void MultiplicativeEnvelope<Type>::getBlock(absl::Span<Type> output)
         }
 
         const auto step = std::exp((std::log(event.second) - std::log(currentValue)) / length);
-        currentValue = multiplicativeRamp<Type>(output.subspan(index, length), currentValue, step);
+        multiplicativeRamp<Type>(output.subspan(index, length), currentValue, step);
+        currentValue = event.second;
         index += length;
     }
 
diff --git a/tests/EventEnvelopesT.cpp b/tests/EventEnvelopesT.cpp
index 4213f04a..10fc2c0d 100644
--- a/tests/EventEnvelopesT.cpp
+++ b/tests/EventEnvelopesT.cpp
@@ -22,6 +22,8 @@
 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "EventEnvelopes.h"
+#include "SfzHelpers.h"
+#include "Buffer.h"
 #include "catch2/catch.hpp"
 #include <absl/algorithm/container.h>
 #include <absl/types/span.h>
@@ -385,3 +387,20 @@ TEST_CASE("[MultiplicativeEnvelope] Going down quantized with 2 steps and starti
     envelope.getQuantizedBlock(absl::MakeSpan(output), 2.0f);
     REQUIRE(output == expected);
 }
+
+TEST_CASE("[MultiplicativeEnvelope] Pitch envelope basic function")
+{
+    sfz::Buffer<float> output { 256 };
+    sfz::MultiplicativeEnvelope<float> envelope;
+    envelope.setFunction([](float pitchValue){
+        const auto normalizedBend = sfz::normalizeBend(pitchValue);
+        const auto bendInCents = normalizedBend * 200;
+        return sfz::centsFactor(bendInCents);
+    });
+    envelope.reset(0);
+    envelope.getBlock(absl::MakeSpan(output));
+    REQUIRE(output[255] == 1.0_a);
+    envelope.registerEvent(252, -6020);
+    envelope.getBlock(absl::MakeSpan(output));
+    REQUIRE(output[255] == Approx(0.9168).epsilon(0.01));
+}