Merge pull request #127 from jpcima/wavetable-phase

Add support of oscillator_phase

src/sfizz/Defaults.h

@@ -53,6 +53,10 @@ namespace Default
 	constexpr SfzLoopMode loopMode { SfzLoopMode::no_loop };
 	constexpr Range<uint32_t> loopRange { 0, std::numeric_limits<uint32_t>::max() };
 
+    // Wavetable oscillator
+    constexpr float oscillatorPhase { 0.0 };
+    constexpr Range<float> oscillatorPhaseRange { -1.0, 360.0 };
+
     // Instrument setting: voice lifecycle
 	constexpr uint32_t group { 0 };
 	constexpr Range<uint32_t> groupRange { 0, std::numeric_limits<uint32_t>::max() };

src/sfizz/Region.cpp

@@ -95,6 +95,11 @@ bool sfz::Region::parseOpcode(const Opcode& opcode)
         setRangeStartFromOpcode(opcode, loopRange, Default::loopRange);
         break;
 
+    // Wavetable oscillator
+    case hash("oscillator_phase"):
+        setValueFromOpcode(opcode, oscillatorPhase, Default::oscillatorPhaseRange);
+        break;
+
     // Instrument settings: voice lifecycle
     case hash("group"): // fallthrough
     case hash("polyphony_group"):

src/sfizz/Region.h

@@ -226,6 +226,9 @@ struct Region {
     absl::optional<SfzLoopMode> loopMode {}; // loopmode
     Range<uint32_t> loopRange { Default::loopRange }; //loopstart and loopend
 
+    // Wavetable oscillator
+    float oscillatorPhase { Default::oscillatorPhase };
+
     // Instrument settings: voice lifecycle
     uint32_t group { Default::group }; // group
     absl::optional<uint32_t> offBy {}; // off_by

src/sfizz/Voice.cpp

@@ -58,6 +58,17 @@ void sfz::Voice::startVoice(Region* region, int delay, int number, uint8_t value
             break;
         }
         waveOscillator.setWavetable(wave);
+
+        float phase;
+        const float phaseParam = region->oscillatorPhase;
+        if (phaseParam >= 0) {
+            phase = phaseParam * (1.0f / 360.0f);
+            phase -= static_cast<int>(phase);
+        } else {
+            std::uniform_real_distribution<float> phaseDist { 0.0001f, 0.9999f };
+            phase = phaseDist(Random::randomGenerator);
+        }
+        waveOscillator.setPhase(phase);
     } else {
         currentPromise = resources.filePool.getFilePromise(region->sample);
         if (currentPromise == nullptr) {

src/sfizz/Wavetables.cpp

@@ -30,6 +30,12 @@ void WavetableOscillator::setWavetable(const WavetableMulti* wave)
     _multi = wave ? wave : &silenceMulti;
 }
 
+void WavetableOscillator::setPhase(float phase)
+{
+    ASSERT(phase >= 0.0f && phase <= 1.0f);
+    _phase = phase;
+}
+
 void WavetableOscillator::process(float frequency, float* output, unsigned nframes)
 {
     float phase = _phase;

src/sfizz/Wavetables.h

@@ -37,6 +37,11 @@ public:
      */
     void setWavetable(const WavetableMulti* wave);
 
+    /**
+       Set the current phase of this oscillator, between 0 and 1 excluded.
+     */
+    void setPhase(float phase);
+
     /**
        Compute a cycle of the oscillator, with constant frequency.
      */

tests/RegionT.cpp

@@ -1392,6 +1392,19 @@ TEST_CASE("[Region] Parsing opcodes")
         region.parseOpcode({ "effect3", "-50.65" });
         REQUIRE(region.gainToEffect[3] == 0.0f);
     }
+
+    SECTION("Wavetable phase")
+    {
+        REQUIRE(region.oscillatorPhase == 0.0f);
+        region.parseOpcode({ "oscillator_phase", "45" });
+        REQUIRE(region.oscillatorPhase == 45.0f);
+        region.parseOpcode({ "oscillator_phase", "45.32" });
+        REQUIRE(region.oscillatorPhase == 45.32_a);
+        region.parseOpcode({ "oscillator_phase", "-1" });
+        REQUIRE(region.oscillatorPhase == -1.0f);
+        region.parseOpcode({ "oscillator_phase", "361" });
+        REQUIRE(region.oscillatorPhase == 360.0f);
+    }
 }
 
 // Specific region bugs