add wavetables

src/synth/Oscillator.cpp

@@ -1,6 +1,10 @@
 
 #include "Oscillator.h"
 
+Oscillator::Oscillator(WavetableController* wavetable) : wavetable_(wavetable) {
+
+}
+
 void Oscillator::setWavetable(uint8_t waveTableId) {
     activeWavetable_ = waveTableId;
 }
@@ -20,33 +24,10 @@ float Oscillator::process(uint8_t note, bool& scopeTrigger) {
 
 float Oscillator::process(float frequency, bool& scopeTrigger) {
 
-    float sampleOut = 0.0f;
     float pitchOffset = 0.5f;
     float phaseInc = pitchOffset * 2.0f * M_PI * frequency / sampleRate_;
 
-    switch (activeWavetable_) {
-    case 0: // sine
-        sampleOut = std::sin(phase_) / 0.707f;
-        break;
-    case 1: // square
-        sampleOut = (phase_ >= M_PI) ? 1.0f : -1.0f;
-        break;
-    case 2: // saw
-        sampleOut = ((phase_ / M_PI) - 1.0f) / 0.577f;
-        break;
-    case 3: // triangle
-        if(phase_ <= M_PI/2.0f) {
-            sampleOut = phase_ * 2.0f/M_PI;
-        } else if(phase_ <= 3.0f*M_PI/2.0f) {
-            sampleOut = phase_ * -2.0f/M_PI + 2.0f;
-        } else {
-            sampleOut = phase_ * 2.0f/M_PI - 4.0f;
-        }
-        sampleOut /= 0.577f; 
-        break;
-    default: // unreachable
-        break;
-    }
+    float sampleOut = wavetable_->sample(activeWavetable_, phase_);
 
     phase_ += phaseInc;
     if (phase_ > 2.0f * M_PI) {

src/synth/Oscillator.h

@@ -1,6 +1,8 @@
 
 #pragma once
 
+#include "WavetableController.h"
+
 #include <cstdint>
 #include <cmath>
 #include <array>
@@ -13,12 +15,12 @@
 #define SYNTH_PITCH_STANDARD 440.0f // frequency of home pitch
 #define SYNTH_MIDI_HOME 69 // midi note index of home pitch
 #define SYNTH_NOTES_PER_OCTAVE 12
-#define SYNTH_WAVETABLE_SIZE 2048
 
 class Oscillator {
 public:
 
     Oscillator() = default;
+    Oscillator(WavetableController* wavetable);
     ~Oscillator() = default;
 
     void setWavetable(uint8_t waveTableId);
@@ -39,12 +41,7 @@ private:
     uint8_t activeWavetable_;
     float frequency_ = 220.0f;
 
-    // TODO: implement
-    // TODO: wavetable class that can load from files
-    // TODO: wavetables should be shared among the entire synth
-    std::array<float, SYNTH_WAVETABLE_SIZE> wavetable1_;
-    std::array<float, SYNTH_WAVETABLE_SIZE> wavetable2_;
-    std::array<float, SYNTH_WAVETABLE_SIZE> wavetable3_;
-    std::array<float, SYNTH_WAVETABLE_SIZE> wavetable4_;
+    // wavetables
+    WavetableController* wavetable_;
 
 };

src/synth/Synth.cpp

@@ -9,7 +9,7 @@
 #endif
 
 Synth::Synth(const ParameterStore& params) : paramStore_(params) {
-    voices_.fill(Voice(params_.data()));
+    voices_.fill(Voice(params_.data(), &wavetable_));
 }
 
 void Synth::updateParams() {

src/synth/Synth.h

@@ -7,6 +7,7 @@
 #include "ScopeBuffer.h"
 #include "Filter.h"
 #include "Voice.h"
+#include "WavetableController.h"
 
 #include <vector>
 #include <atomic>
@@ -54,4 +55,7 @@ private:
 
     std::chrono::time_point<std::chrono::high_resolution_clock> lastTime;
 
+    // waveforms
+    WavetableController wavetable_;
+    
 };

src/synth/Voice.cpp

@@ -3,8 +3,9 @@
 #include <cmath>
 #include <iostream>
 
-Voice::Voice(SmoothedParam* params) : params_(params) {
+Voice::Voice(SmoothedParam* params, WavetableController* wavetable) : params_(params), wavetable_(wavetable) {
 
+    oscillators_.fill(Oscillator(wavetable_));
 }
 
 // cascade sample rate to all descendant objects
@@ -82,9 +83,17 @@ float Voice::process(float* params, bool& scopeTrigger) {
 
     // sample generation
     uint8_t osc1Wave = (static_cast<uint8_t>(std::round(getParam(ParamId::Osc1WaveSelector1))));
-    oscillators_[0].setWavetable(osc1Wave);
+    for(Oscillator& o : oscillators_) {
+        o.setWavetable(osc1Wave);
+    }
 
-    float sampleOut = oscillators_[0].process(note_, scopeTrigger) * gain;
+    // TODO: oscillator pitch offset
+    bool temp = false;
+    float osc1 = oscillators_[0].process(note_, scopeTrigger);
+    float osc2 = oscillators_[1].process(static_cast<uint8_t>(note_+12), temp);
+    float osc3 = oscillators_[2].process(static_cast<uint8_t>(note_+19), temp);
+    
+    float sampleOut = (osc1 + osc2*0.5f + osc3*0.25f) * gain;
 
     // filter sample
     float baseFreq = oscillators_[0].frequency();

src/synth/Voice.h

@@ -25,7 +25,7 @@ class Voice {
 public:
 
     Voice() = default;
-    Voice(SmoothedParam* params);
+    Voice(SmoothedParam* params, WavetableController* wavetable);
     ~Voice() = default;
 
     void setSampleRate(float sampleRate);
@@ -67,6 +67,9 @@ private:
     // paramstore pointer
     SmoothedParam* params_;
 
+    // wavetables
+    WavetableController* wavetable_;
+
     // TODO: add a parameter in the paramstore for this
     float velocitySensitivity = 0.7f;
     float velocityCenter = 2.0f;