Keep voice settings and restore them after polyphony change

src/sfizz/Synth.cpp

@@ -491,11 +491,11 @@ void sfz::Synth::finalizeSfzLoad()
     regions.resize(currentRegionCount);
     modificationTime = checkModificationTime();
 
-    for (auto& voice : voices) {
+    settingsPerVoice.maxFilters = maxFilters;
-        voice->setMaxFiltersPerVoice(maxFilters);
+    settingsPerVoice.maxEQs = maxEQs;
-        voice->setMaxEQsPerVoice(maxEQs);
+    settingsPerVoice.maxModifiers = maxModifiers;
-        voice->prepareSmoothers(maxModifiers);
+
-    }
+    applySettingsPerVoice();
 }
 
 bool sfz::Synth::loadScalaFile(const fs::path& path)
@@ -1205,6 +1205,17 @@ void sfz::Synth::resetVoices(int numVoices)
     }
 
     this->numVoices = numVoices;
+
+    applySettingsPerVoice();
+}
+
+void sfz::Synth::applySettingsPerVoice()
+{
+    for (auto& voice : voices) {
+        voice->setMaxFiltersPerVoice(settingsPerVoice.maxFilters);
+        voice->setMaxEQsPerVoice(settingsPerVoice.maxEQs);
+        voice->prepareSmoothers(settingsPerVoice.maxModifiers);
+    }
 }
 
 void sfz::Synth::setOversamplingFactor(sfz::Oversampling factor) noexcept

src/sfizz/Synth.h

@@ -631,6 +631,10 @@ private:
      * @param numVoices
      */
     void resetVoices(int numVoices);
+    /**
+     * @brief Make the stored settings take effect in all the voices
+     */
+    void applySettingsPerVoice();
 
     /**
      * @brief Render the voice to its designated outputs and effect busses.
@@ -702,6 +706,14 @@ private:
     int noteOffset { 0 };
     int octaveOffset { 0 };
 
+    // Settings per voice
+    struct SettingsPerVoice {
+        size_t maxFilters { 0 };
+        size_t maxEQs { 0 };
+        ModifierArray<size_t> maxModifiers { 0 };
+    };
+    SettingsPerVoice settingsPerVoice;
+
     Duration dispatchDuration { 0 };
 
     Parser parser;