Add SFZ support of generators

src/CMakeLists.txt

@@ -18,6 +18,7 @@ set (SFIZZ_SOURCES
     sfizz/SfzFilter.cpp
     sfizz/Curve.cpp
     sfizz/Wavetables.cpp
+    sfizz/Resources.cpp
     sfizz/Effects.cpp
     sfizz/effects/Nothing.cpp
     sfizz/effects/Filter.cpp

src/sfizz/Resources.cpp

@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: BSD-2-Clause
+
+// This code is part of the sfizz library and is licensed under a BSD 2-clause
+// license. You should have receive a LICENSE.md file along with the code.
+// If not, contact the sfizz maintainers at https://github.com/sfztools/sfizz
+
+#include "Resources.h"
+#include "Wavetables.h"
+
+namespace sfz
+{
+
+static constexpr unsigned kTableSize = 1024;
+
+// amplitude values are matched to reference
+static constexpr double kAmplitudeSine = 0.625;
+static constexpr double kAmplitudeTriangle = 0.625;
+static constexpr double kAmplitudeSaw = 0.515;
+static constexpr double kAmplitudeSquare = 0.515;
+
+static const WavetableMulti* getWaveSin()
+{
+    static auto wave = WavetableMulti::createForHarmonicProfile(
+        HarmonicProfile::getSine(), kAmplitudeSine, kTableSize);
+    return &wave;
+}
+
+static const WavetableMulti* getWaveTriangle()
+{
+    static auto wave = WavetableMulti::createForHarmonicProfile(
+        HarmonicProfile::getTriangle(), kAmplitudeTriangle, kTableSize);
+    return &wave;
+}
+
+static const WavetableMulti* getWaveSaw()
+{
+    static auto wave = WavetableMulti::createForHarmonicProfile(
+        HarmonicProfile::getSaw(), kAmplitudeSaw, kTableSize);
+    return &wave;
+}
+
+static const WavetableMulti* getWaveSquare()
+{
+    static auto wave = WavetableMulti::createForHarmonicProfile(
+        HarmonicProfile::getSquare(), kAmplitudeSquare, kTableSize);
+    return &wave;
+}
+
+Resources::Resources()
+    : waveSin(getWaveSin()),
+      waveTriangle(getWaveTriangle()),
+      waveSaw(getWaveSaw()),
+      waveSquare(getWaveSquare())
+{
+}
+
+
+}

src/sfizz/Resources.h

@@ -12,6 +12,8 @@
 
 namespace sfz
 {
+class WavetableMulti;
+
 struct Resources
 {
     MidiState midiState;
@@ -19,5 +21,12 @@ struct Resources
     FilePool filePool { logger };
     FilterPool filterPool { midiState };
     EQPool eqPool { midiState };
+
+    const WavetableMulti* waveSin { nullptr };
+    const WavetableMulti* waveTriangle { nullptr };
+    const WavetableMulti* waveSaw { nullptr };
+    const WavetableMulti* waveSquare { nullptr };
+
+    Resources();
 };
 }

src/sfizz/Voice.cpp

@@ -20,6 +20,8 @@ sfz::Voice::Voice(sfz::Resources& resources)
 {
     filters.reserve(config::filtersPerVoice);
     equalizers.reserve(config::eqsPerVoice);
+
+    waveOscillator.init(sampleRate);
 }
 
 void sfz::Voice::startVoice(Region* region, int delay, int number, uint8_t value, sfz::Voice::TriggerType triggerType) noexcept
@@ -35,7 +37,28 @@ void sfz::Voice::startVoice(Region* region, int delay, int number, uint8_t value
     if (delay < 0)
         delay = 0;
 
-    if (!region->isGenerator()) {
+    if (region->isGenerator()) {
+        const WavetableMulti* wave = nullptr;
+        switch (hash(region->sample)) {
+        default:
+        case hash("*silence"):
+            break;
+        case hash("*sine"):
+            wave = resources.waveSin;
+            break;
+        case hash("*triangle"):
+        case hash("*tri"):
+            wave = resources.waveTriangle;
+            break;
+        case hash("*square"):
+            wave = resources.waveSquare;
+            break;
+        case hash("*saw"):
+            wave = resources.waveSaw;
+            break;
+        }
+        waveOscillator.setWavetable(wave);
+    } else {
         currentPromise = resources.filePool.getFilePromise(region->sample);
         if (currentPromise == nullptr) {
             reset();
@@ -226,6 +249,8 @@ void sfz::Voice::registerTempo(int delay, float secondsPerQuarter) noexcept
 void sfz::Voice::setSampleRate(float sampleRate) noexcept
 {
     this->sampleRate = sampleRate;
+
+    waveOscillator.init(sampleRate);
 }
 
 void sfz::Voice::setSamplesPerBlock(int samplesPerBlock) noexcept
@@ -472,38 +497,26 @@ void sfz::Voice::fillWithGenerator(AudioSpan<float> buffer) noexcept
 {
     const auto leftSpan = buffer.getSpan(0);
     const auto rightSpan  = buffer.getSpan(1);
+
     if (region->sample == "*noise") {
         absl::c_generate(leftSpan, [&](){ return noiseDist(Random::randomGenerator); });
         absl::c_generate(rightSpan, [&](){ return noiseDist(Random::randomGenerator); });
-    }
-    else if (region->sample == "*sine") {
-        // TODO: wavetables for sine and other generators
-        if (buffer.getNumFrames() == 0)
-            return;
-
-        auto jumps = tempSpan1.first(buffer.getNumFrames());
+    } else {
+        // wavetables for sine and other generators
+        auto frequencies = tempSpan1.first(buffer.getNumFrames());
         auto bends = tempSpan2.first(buffer.getNumFrames());
-        auto phases = tempSpan2.first(buffer.getNumFrames());
 
-        const float step = baseFrequency * twoPi<float>() / sampleRate;
-        fill<float>(jumps, step);
+        fill<float>(frequencies, baseFrequency);
 
         if (region->bendStep > 1)
             pitchBendEnvelope.getQuantizedBlock(bends, bendStepFactor);
         else
             pitchBendEnvelope.getBlock(bends);
 
-        applyGain<float>(bends, jumps);
-        jumps[0] += phase;
-        cumsum<float>(jumps, phases);
-        phase = phases.back();
+        applyGain<float>(bends, frequencies);
 
-        sin<float>(phases, leftSpan);
+        waveOscillator.processModulated(frequencies.data(), leftSpan.data(), buffer.getNumFrames());
         copy<float>(leftSpan, rightSpan);
-
-        // Wrap the phase so we don't loose too much precision on longer notes
-        const auto numTwoPiWraps = static_cast<int>(phase / twoPi<float>());
-        phase -= twoPi<float>() * static_cast<float>(numTwoPiWraps);
     }
 }
 

src/sfizz/Voice.h

@@ -12,6 +12,7 @@
 #include "Region.h"
 #include "AudioBuffer.h"
 #include "MidiState.h"
+#include "Wavetables.h"
 #include "Resources.h"
 #include "AudioSpan.h"
 #include "LeakDetector.h"
@@ -307,6 +308,8 @@ private:
     MultiplicativeEnvelope<float> volumeEnvelope;
     float bendStepFactor { centsFactor(1) };
 
+    WavetableOscillator waveOscillator;
+
     Duration dataDuration;
     Duration amplitudeDuration;
     Duration panningDuration;

src/sfizz/Wavetables.cpp

@@ -218,14 +218,11 @@ WavetableRange WavetableRange::getRangeForFrequency(float f)
 constexpr unsigned WavetableMulti::_tableExtra;
 
 WavetableMulti WavetableMulti::createForHarmonicProfile(
-    const HarmonicProfile& hp, unsigned tableSize, double refSampleRate)
+    const HarmonicProfile& hp, double amplitude, unsigned tableSize, double refSampleRate)
 {
     WavetableMulti wm;
     constexpr unsigned multiSize = WavetableMulti::multiSize();
 
-    // amplitude to match ARIA's default generator output
-    constexpr double amplitude = 0.25;
-
     wm.allocateStorage(tableSize);
 
     for (unsigned m = 0; m < multiSize; ++m) {

src/sfizz/Wavetables.h

@@ -146,7 +146,7 @@ public:
     // the reference sample rate is the minimum value accepted by the DSP
     // system (most defavorable wrt. aliasing)
     static WavetableMulti createForHarmonicProfile(
-        const HarmonicProfile& hp, unsigned tableSize, double refSampleRate = 44100.0);
+        const HarmonicProfile& hp, double amplitude, unsigned tableSize, double refSampleRate = 44100.0);
 
     // create the tiniest wavetable with null content for use with oscillators
     static WavetableMulti createSilence();

tests/DemoWavetables.cpp

@@ -84,13 +84,13 @@ bool DemoApp::initSound()
     fTmpFrequency.reset(new float[bufferSize]);
 
     fMulti[0] = sfz::WavetableMulti::createForHarmonicProfile(
-        sfz::HarmonicProfile::getSine(), 2048);
+        sfz::HarmonicProfile::getSine(), 1.0, 2048);
     fMulti[1] = sfz::WavetableMulti::createForHarmonicProfile(
-        sfz::HarmonicProfile::getTriangle(), 2048);
+        sfz::HarmonicProfile::getTriangle(), 1.0, 2048);
     fMulti[2] = sfz::WavetableMulti::createForHarmonicProfile(
-        sfz::HarmonicProfile::getSaw(), 2048);
+        sfz::HarmonicProfile::getSaw(), 1.0, 2048);
     fMulti[3] = sfz::WavetableMulti::createForHarmonicProfile(
-        sfz::HarmonicProfile::getSquare(), 2048);
+        sfz::HarmonicProfile::getSquare(), 1.0, 2048);
 
     fClient.reset(client);
 

tests/PlotWavetables.cpp

@@ -67,7 +67,7 @@ int main(int argc, char* argv[])
             std::cout << (i * (1.0 / tableSize)) << ' ' << table[i] << '\n';
     } else {
         sfz::WavetableMulti multi = sfz::WavetableMulti::createForHarmonicProfile(
-            *hp, tableSize);
+            *hp, 1.0, tableSize);
         unsigned multiSize = multi.multiSize();
 
         if (true) {