Initial grafting of the filters in the voice process (untested)

src/sfizz/Config.h

@@ -53,7 +53,9 @@ namespace config {
     constexpr uint8_t numCCs { 143 };
     constexpr int chunkSize { 1024 };
     constexpr float defaultAmpEGRelease { 0.02f };
-    constexpr int defaultNumFilters { maxVoices * 2 };
+    constexpr int filtersInPool { maxVoices * 2 };
+    constexpr int filtersPerVoice { 2 };
+    constexpr int eqsPerVoice { 3 };
     /**
        Minimum interval in frames between recomputations of coefficients of the
        modulated filter. The lower, the more CPU resources are consumed.

src/sfizz/FilterPool.h

@@ -77,7 +77,7 @@ public:
      * @param state the associated midi state
      * @param numFilters the number of inactive filters to hold in the pool
      */
-    FilterPool(const MidiState& state, int numFilters = config::defaultNumFilters);
+    FilterPool(const MidiState& state, int numFilters = config::filtersInPool);
     /**
      * @brief Get a filter object to use in Voices
      *

src/sfizz/Synth.cpp

@@ -234,6 +234,9 @@ bool sfz::Synth::loadSfzFile(const fs::path& file)
         ++lastRegion;
     };
 
+    size_t maxFilters { 0 };
+    size_t maxEQs { 0 };
+
     while (currentRegion < lastRegion.base()) {
         auto region = currentRegion->get();
 
@@ -316,6 +319,8 @@ bool sfz::Synth::loadSfzFile(const fs::path& file)
         region->registerPitchWheel(0);
         region->registerAftertouch(0);
         region->registerTempo(2.0f);
+        maxFilters = max(maxFilters, region->filters.size());
+        maxEQs = max(maxEQs, region->equalizers.size());
 
         ++currentRegion;
     }
@@ -324,6 +329,11 @@ bool sfz::Synth::loadSfzFile(const fs::path& file)
     regions.resize(remainingRegions);
     modificationTime = checkModificationTime();
 
+    for (auto& voice: voices) {
+        voice->setMaxFiltersPerVoice(maxFilters);
+        voice->setMaxEQsPerVoice(maxEQs);
+    }
+
     return parserReturned;
 }
 

src/sfizz/Voice.cpp

@@ -17,6 +17,8 @@
 sfz::Voice::Voice(sfz::Resources& resources)
 : resources(resources)
 {
+    filters.reserve(config::filtersPerVoice);
+    equalizers.reserve(config::filtersPerVoice);
 }
 
 void sfz::Voice::startVoice(Region* region, int delay, int number, uint8_t value, sfz::Voice::TriggerType triggerType) noexcept
@@ -85,6 +87,18 @@ void sfz::Voice::startVoice(Region* region, int delay, int number, uint8_t value
     });
     pitchBendEnvelope.reset(static_cast<float>(resources.midiState.getPitchBend()));
 
+    // Check that we can handle the number of filters; filters should be cleared here
+    ASSERT((filters.capacity() - filters.size()) >= region->filters.size());
+    ASSERT((equalizers.capacity() - equalizers.size()) >= region->equalizers.size());
+
+    for(auto& filter: region->filters) {
+        auto newFilter = resources.filterPool.getFilter(filter, number, value);
+        if (newFilter)
+            filters.push_back(newFilter);
+    }
+
+    // TODO: Equalizers
+
     sourcePosition = region->getOffset();
     triggerDelay = delay;
     initialDelay = delay + static_cast<uint32_t>(region->getDelay() * sampleRate);
@@ -258,6 +272,12 @@ void sfz::Voice::renderBlock(AudioSpan<float> buffer) noexcept
     else
         processMono(buffer);
 
+    const float* inputChannels[2] { buffer.getChannel(0), buffer.getChannel(1) };
+    float* outputChannels[2] { buffer.getChannel(0), buffer.getChannel(1) };
+    for (auto filter: filters) {
+        filter->process(inputChannels, outputChannels, buffer.getNumFrames());
+    }
+
     if (!egEnvelope.isSmoothing())
         reset();
 
@@ -528,6 +548,8 @@ void sfz::Voice::reset() noexcept
     sourcePosition = 0;
     floatPositionOffset = 0.0f;
     noteIsOff = false;
+    filters.clear();
+    equalizers.clear();
 }
 
 float sfz::Voice::getMeanSquaredAverage() const noexcept
@@ -544,3 +566,17 @@ uint32_t sfz::Voice::getSourcePosition() const noexcept
 {
     return sourcePosition;
 }
+
+void sfz::Voice::setMaxFiltersPerVoice(size_t numFilters)
+{
+    // There are filters in there, this call is unexpected
+    ASSERT(filters.size() == 0);
+    filters.reserve(numFilters);
+}
+
+void sfz::Voice::setMaxEQsPerVoice(size_t numFilters)
+{
+    // There are filters in there, this call is unexpected
+    ASSERT(filters.size() == 0);
+    filters.reserve(numFilters);
+}

src/sfizz/Voice.h

@@ -196,6 +196,18 @@ public:
      * @return
      */
     const Region* getRegion() const noexcept { return region; }
+    /**
+     * @brief Set the max number of filters per voice
+     *
+     * @param numFilters
+     */
+    void setMaxFiltersPerVoice(size_t numFilters);
+    /**
+     * @brief Set the max number of EQs per voice
+     *
+     * @param numFilters
+     */
+    void setMaxEQsPerVoice(size_t numEQs);
 private:
     /**
      * @brief Fill a span with data from a file source. This is the first step
@@ -283,6 +295,9 @@ private:
 
     Resources& resources;
 
+    std::vector<FilterHolderPtr> filters;
+    std::vector<FilterHolderPtr> equalizers;
+
     ADSREnvelope<float> egEnvelope;
     LinearEnvelope<float> amplitudeEnvelope; // linear events
     LinearEnvelope<float> crossfadeEnvelope;