added support for pitch wheel modulation

synth/midi_event.h

@@ -0,0 +1,46 @@
+#pragma once
+
+namespace trnr {
+
+enum midi_event_type {
+    note_on = 0,
+    note_off,
+    pitch_wheel,
+    mod_wheel
+};
+
+class midi_event {
+public:
+    midi_event_type type;
+    int offset = 0;
+    int midi_note = 0;
+    float velocity = 1.f;
+    double data = 0;
+
+    void make_note_on(int _midi_note, float _velocity, int _offset = 0)
+    {
+        type = midi_event_type::note_on;
+        midi_note = _midi_note;
+        velocity = _velocity;
+        offset = _offset;
+    }
+
+    void make_note_off(int _midi_note, float _velocity, int _offset = 0)
+    {
+        type = midi_event_type::note_off;
+        midi_note = _midi_note;
+        velocity = _velocity;
+        offset = _offset;
+    }
+
+    void make_pitch_weel(double _pitch, int _offset = 0) {
+        type = midi_event_type::pitch_wheel;
+        data = _pitch;
+    }
+
+    void make_mod_weel(double _mod, int _offset = 0) {
+        type = midi_event_type::pitch_wheel;
+        data = _mod;
+    }
+};
+}

synth/midi_synth.h

@@ -1,7 +1,7 @@
 #pragma once
 #include <memory>
 #include <vector>
-#include "note_event.h"
+#include "midi_event.h"
 #include "voice_allocator.h"
 
 namespace trnr {
@@ -35,7 +35,7 @@ public:
                     block_size = samples_remaining;
 
                 while (!m_event_queue.empty()) {
-                    note_event event = m_event_queue.front();
+                    midi_event event = m_event_queue.front();
 
                     // we assume the messages are in chronological order. If we find one later than the current block we are done.
                     if (event.offset > start_index + block_size)
@@ -66,9 +66,9 @@ public:
         }
     }
     
-    void add_event(note_event event)
+    void add_event(midi_event event)
     {
-        if (event.type == note_event_type::note_on)
+        if (event.type == midi_event_type::note_on)
             m_voices_active = true;
 
         m_event_queue.push_back(event);
@@ -82,7 +82,7 @@ public:
     }
 
 private:
-    std::vector<note_event> m_event_queue;
+    std::vector<midi_event> m_event_queue;
     int m_block_size;
     bool m_voices_active;
 };

synth/note_event.h

@@ -1,25 +0,0 @@
-#pragma once
-
-namespace trnr {
-
-enum note_event_type {
-    note_on = 0,
-    note_off
-};
-
-class note_event {
-public:
-    note_event_type type;
-    int midi_note;
-    float velocity;
-    int offset;
-
-    note_event(note_event_type type, int _midi_note, float _velocity, int _offset)
-        : type { type }
-        , midi_note { _midi_note }
-        , velocity { _velocity }
-        , offset { _offset }
-    {
-    }
-};
-}

synth/tx_voice.h

@@ -20,7 +20,8 @@ public:
     bool trigger = false;
     int midi_note = 0;
     float velocity = 1.f;
-    float pitch_mod = 0.f;
+    float pitch_mod = 0.f; // modulates pitch in semi-tones
+    float pitch_mod2 = 0.f; // modulates pitch in frequency
 
     int algorithm;
     float pitch_env_amt;
@@ -45,7 +46,7 @@ public:
 
     float process_sample() {
         float pitch_env_signal = pitch_env.process_sample(gate, trigger) * pitch_env_amt;
-        float pitched_freq = midi_to_frequency(midi_note) + pitch_env_signal + pitch_mod;
+        float pitched_freq = midi_to_frequency(midi_note + pitch_mod) + pitch_env_signal + pitch_mod2;
 
         float output = 0.f;
 

synth/voice_allocator.h

@@ -1,6 +1,6 @@
 #pragma once
+#include "midi_event.h"
 #include <vector>
-#include "note_event.h"
 
 namespace trnr {
 
@@ -8,7 +8,7 @@ template <typename t_voice>
 class voice_allocator {
 public:
     std::vector<t_voice> voices;
-    
+
     voice_allocator()
         : voices(8, t_voice())
     {
@@ -19,7 +19,7 @@ public:
         voices.resize(voice_count, voices.at(0));
     }
 
-    void note_on(const note_event& event)
+    void note_on(const midi_event& event)
     {
         t_voice* voice = get_free_voice(event.midi_note);
 
@@ -32,7 +32,7 @@ public:
         }
     }
 
-    void note_off(const note_event& event)
+    void note_off(const midi_event& event)
     {
         for (auto it = voices.begin(); it != voices.end(); it++) {
             if ((*it).midi_note == event.midi_note) {
@@ -63,7 +63,7 @@ public:
         }
     }
 
-    void add_event(note_event event)
+    void add_event(midi_event event)
     {
         input_queue.push_back(event);
     }
@@ -88,7 +88,7 @@ public:
     }
 
 private:
-    std::vector<note_event> input_queue;
+    std::vector<midi_event> input_queue;
 
     t_voice* get_free_voice(float frequency)
     {
@@ -126,16 +126,21 @@ private:
         auto iterator = input_queue.begin();
         while (iterator != input_queue.end()) {
 
-            note_event& event = *iterator;
+            midi_event& event = *iterator;
             if (event.offset == _start_index) {
 
                 switch (event.type) {
-                case note_event_type::note_on:
+                case midi_event_type::note_on:
                     note_on(event);
                     break;
-                case note_event_type::note_off:
+                case midi_event_type::note_off:
                     note_off(event);
                     break;
+                case midi_event_type::pitch_wheel:
+                    access([&event](t_voice& voice) { voice.pitch_mod = event.data; });
+                    break;
+                default:
+                    break;
                 }
 
                 iterator = input_queue.erase(iterator);

util/audio_math.h

@@ -9,7 +9,7 @@ namespace trnr {
 		return pow(10, db/20);
 	}
 
-	static inline float midi_to_frequency(int midi_note) {
+	static inline float midi_to_frequency(float midi_note) {
 			return 440.0 * powf(2.0, ((float)midi_note - 69.0) / 12.0);
 	}
 }