fix: refactor code structure into files (#8)

closes #7

Co-authored-by: HiveBeats <e1lama@protonmail.com>
Reviewed-on: #8

.vscode/tasks.json

@@ -9,7 +9,11 @@
                 "-fansi-escape-codes",
                 "-g",
                 "${file}",
+                "${fileDirname}/utils.c",
+                "${fileDirname}/ring_buffer.c",
+                "${fileDirname}/oscillator.c",
                 "${fileDirname}/parser.c",
+                "${fileDirname}/export.c",
                 "-lm",
                 "-lraylib",
                 "-o",

build.sh

@@ -1,3 +1,3 @@
 #!/bin/bash
 CC="${CXX:-cc}"
-$CC -Wall -std=c11 ./main.c ./parser.c -lm -lraylib -o ./bin/main
+$CC -Wall -std=c11 ./main.c ./utils.c ./ring_buffer.c ./oscillator.c ./parser.c ./export.c -lm -lraylib -o ./bin/main

export.c

@@ -0,0 +1,74 @@
+#include "export.h"
+
+#include "stdio.h"
+#include "string.h"
+#include "settings.h"
+
+uint16_t toInt16Sample(float sample) {
+    return (uint16_t)(sample * 32767.f);
+}
+
+static void write_file(char* filename, void* data, int size) {
+    FILE* fp = fopen(filename, "wb");  // open file for writing in binary mode
+    if (fp == NULL) {
+        fprintf(stderr, "Cannot open file: %s\n", filename);
+        exit(1);
+    }
+
+    fwrite(data, size, 1, fp);  // write data to file
+
+    fclose(fp);  // close file
+}
+
+void pack(uint16_t* d, size_t length) {
+    size_t dataLength = length * 2;
+
+    int bytesPerSample = 2;
+    int byteRate = SAMPLE_RATE * bytesPerSample;
+
+    size_t fileSize = 36 + dataLength;
+
+    uint8_t* buffer = (uint8_t*)malloc(fileSize);
+
+    int i = 0;
+
+    // RIFF header
+    memcpy(buffer + i, "RIFF", 4);
+    i += 4;
+    memcpy(buffer + i, &fileSize, 4);
+    i += 4;
+    memcpy(buffer + i, "WAVE", 4);
+    i += 4;
+
+    // fmt subchunk
+    memcpy(buffer + i, "fmt ", 4);
+    i += 4;
+    int fmtSize = 16;
+    memcpy(buffer + i, &fmtSize, 4);
+    i += 4;
+    uint16_t audioFormat = 1;
+    memcpy(buffer + i, &audioFormat, 2);
+    i += 2;
+    uint16_t numChannels = 1;
+    memcpy(buffer + i, &numChannels, 2);
+    i += 2;
+    int sampleRate = (int)SAMPLE_RATE;
+    memcpy(buffer + i, &sampleRate, 4);
+    i += 4;
+    memcpy(buffer + i, &byteRate, 4);
+    i += 4;
+    memcpy(buffer + i, &bytesPerSample, 2);
+    i += 2;
+    int bitsPerSample = bytesPerSample * 8;
+    memcpy(buffer + i, &bitsPerSample, 2);
+    i += 2;
+
+    // data subchunk
+    memcpy(buffer + i, "data", 4);
+    i += 4;
+    memcpy(buffer + i, &dataLength, 4);
+    i += 4;
+    memcpy(buffer + i, d, dataLength);
+
+    write_file("output.wav", buffer, fileSize);
+}

export.h

@@ -0,0 +1,9 @@
+#ifndef EXPORT_H
+#define EXPORT_H
+
+#include "stdlib.h"
+
+uint16_t toInt16Sample(float sample);
+void pack(uint16_t* d, size_t length);
+
+#endif

main.c

@@ -2,350 +2,16 @@
 #include "stdio.h"
 #include "string.h"
 #include "math.h"
+
 #include "parser.h"
+#include "utils.h"
+#include "ring_buffer.h"
+#include "settings.h"
+#include "oscillator.h"
+#include "export.h"
 
 #include "raylib.h"
 
-#define SAMPLE_RATE 48000.f
-#define BPM 120.f
-#define BEAT_DURATION 60.f/BPM
-#define PITCH_STANDARD 440.f
-#define VOLUME 0.5f
-#define ATTACK_MS 100.f
-#define STREAM_BUFFER_SIZE 4096
-
-#define SYNTH_PI 3.1415926535f
-#define SYNTH_VOLUME 0.5f
-
-#define WINDOW_WIDTH 640
-#define WINDOW_HEIGHT 480
-
-#define write_log(format,args...) do { \
-        printf(format, ## args); \
-    } while(0)
-
-//------------------------------------------------------------------------------------
-// Ring Buffer
-//------------------------------------------------------------------------------------
-
-typedef struct RingBuffer {
-    float* items;
-    size_t head;
-    size_t tail;
-    int is_full;
-    int is_empty;
-    size_t size;
-} RingBuffer;
-
-RingBuffer ring_buffer_init(size_t buffer_size) {
-    RingBuffer buffer = {
-        .items = calloc(buffer_size, sizeof(float)),
-        .head = 0,
-        .tail = 0,
-        .is_full = 0,
-        .is_empty = 1,
-        .size = buffer_size
-    };
-
-    return buffer;
-}
-
-void ring_buffer_reset(RingBuffer* me) {
-    me->head = 0;
-    me->tail = 0;
-    me->is_full = 0;
-}
-
-// +
-static void advance_pointer(RingBuffer* me) {
-    if(me->is_full) {
-        me->tail++;
-		if (me->tail == me->size) { 
-			me->tail = 0;
-		}
-	}
-    me->head++;
-	if (me->head == me->size) { 
-		me->head = 0;
-	}
-    size_t is_full = me->head == me->tail ? 1 : 0;
-	me->is_full = is_full;
-}
-
-// -
-static void retreat_pointer(RingBuffer* me) {
-	me->is_full = 0;
-    me->tail++;
-	if (me->tail == me->size) { 
-		me->tail = 0;
-	}
-}
-
-void ring_buffer_write(RingBuffer* buffer, float* data, size_t count) {
-    if (buffer->is_full || buffer->head + count > buffer->size) {
-        write_log("[WARN] Trying to overfill the ring buffer: \n\tIsFull:%d\n\tHead:%zu\n\tCount:%zu\n\t", 
-            buffer->is_full,
-            buffer->head, 
-            count);
-        return;
-    }
-    buffer->is_empty = 0;
-
-    for (size_t i = 0; i < count; i++) {
-        buffer->items[buffer->head] = data[i];
-        advance_pointer(buffer);
-    }
-    //me->is_empty = is_full && (me->head == me->tail);
-}
-
-int ring_buffer_read(RingBuffer* buffer, float* output, size_t count) {
-    if (buffer->is_empty) {
-        write_log("[WARN] Trying to read empty buffer");
-        return 0;
-    }
-
-    for (size_t i = 0; i < count; i++) {
-        output[i] = buffer->items[buffer->tail];
-        retreat_pointer(buffer);
-    }
-    buffer->is_empty = !buffer->is_full && (buffer->head == buffer->tail);
-    return 1;
-}
-
-size_t ring_buffer_size(RingBuffer* buffer) {
-	size_t size = buffer->size;
-	if(!buffer->is_full) {
-		if(buffer->head >= buffer->tail) {
-			size = (buffer->head - buffer->tail);
-		}
-		else {
-			size = (buffer->size + buffer->head - buffer->tail);
-		}
-	}
-
-	return size;
-}
-
-void ring_buffer_print(RingBuffer* me) {
-    write_log("[INFO] The ring buffer: \n\tIsFull:%d\n\tIsEmpty:%d\n\tHead:%zu\n\tTail:%zu\n\t", 
-                me->is_full, 
-                me->is_empty, 
-                me->head, 
-                me->tail);
-}
-
-
-//------------------------------------------------------------------------------------
-// General SynthSound
-//------------------------------------------------------------------------------------
-
-typedef struct SynthSound {
-    float* samples;
-    size_t sample_count;
-} SynthSound;
-
-// frees the original sounds
-SynthSound concat_sounds(SynthSound* sounds, size_t count) {
-    size_t total_count = 0;
-    for (size_t i = 0; i < count; i++) {
-        total_count += sounds[i].sample_count;
-    }
-    // array to hold the result
-    float* total = malloc(total_count * sizeof(float));
-
-    size_t current_count = 0;
-    for (size_t i = 0; i < count; i++) {
-        memcpy(total + current_count,
-            sounds[i].samples,
-            sounds[i].sample_count * sizeof(float));
-        current_count += sounds[i].sample_count;
-
-        free(sounds[i].samples);
-    }
-
-    SynthSound result = {
-        .samples = total,
-        .sample_count = total_count
-    };
-
-    return result;
-}
-
-//------------------------------------------------------------------------------------
-// Oscillator
-//------------------------------------------------------------------------------------
-
-typedef enum {
-    Sine,
-    Triangle,
-    Saw,
-    Square
-} OscillatorType;
-
-typedef struct OscillatorParameter {
-    OscillatorType osc;
-    float freq;
-} OscillatorParameter;
-
-typedef struct OscillatorParameterList {
-    OscillatorParameter* array;
-    size_t count;
-} OscillatorParameterList;
-
-typedef struct OscillatorGenerationParameter {
-    OscillatorParameterList oscillators;
-    float sample;
-} OscillatorGenerationParameter;
-
-static SynthSound get_init_samples(float duration) {
-    size_t sample_count = (size_t)(duration * SAMPLE_RATE);
-    float* samples = malloc(sizeof(float) * sample_count);
-
-    for (double i = 0.0; i < duration * SAMPLE_RATE; i++) {
-        samples[(int)i] = i;
-    }
-
-    SynthSound res = {
-        .samples = samples,
-        .sample_count = sample_count
-    };
-
-    return res;
-}
-
-static float pos(float hz, float x) {
-    return fmodf(hz * x / SAMPLE_RATE, 1);
-}
-
-float sineosc(float hz, float x) {
-    return sinf(x * (2.f * SYNTH_PI * hz / SAMPLE_RATE));
-}
-
-static float sign(float v) {
-    return (v > 0.0) ? 1.f : -1.f;
-}
-
-float squareosc(float hz, float x) {
-    return sign(sineosc(hz, x));
-}
-
-float triangleosc(float hz, float x) {
-    return 1.f - fabsf(pos(hz, x) - 0.5f) * 4.f;
-}
-
-float sawosc(float hz, float x) {
-    return pos(hz, x) * 2.f - 1.f;
-}
-
-float multiosc(OscillatorGenerationParameter param) {
-    float osc_sample = 0.f;
-    for (size_t i = 0; i < param.oscillators.count; i++) {
-        OscillatorParameter osc = param.oscillators.array[i];
-        switch (osc.osc) {
-            case Sine:
-                osc_sample += sineosc(osc.freq, param.sample);
-                break;
-            case Triangle:
-                osc_sample += triangleosc(osc.freq, param.sample);
-                break;
-            case Square:
-                osc_sample += squareosc(osc.freq, param.sample);
-                break;
-            case Saw:
-                osc_sample += sawosc(osc.freq, param.sample);
-                break;
-        }
-    }
-
-    return osc_sample;
-}
-
-static SynthSound freq(float duration, OscillatorParameterList osc) {
-    SynthSound samples = get_init_samples(duration);
-    // SynthSound attack = get_attack_samples();
-
-    float* output = malloc(sizeof(float) * samples.sample_count);
-    for (int i = 0; i < samples.sample_count; i++) {
-        float sample = samples.samples[i];
-        OscillatorGenerationParameter param = {
-            .oscillators = osc,
-            .sample = sample
-        };
-        output[i] = multiosc(param) * VOLUME;
-    }
-
-    // create attack and release
-    /*
-        let adsrLength = Seq.length output
-        let attackArray = attack |> Seq.take adsrLength
-        let release = Seq.rev attackArray
-    */
-    /*
-     todo: I will change the ADSR approach to an explicit ADSR module(with it's own state)
-    size_t adsr_length = samples.sample_count;
-    float *attackArray = NULL, *releaseArray = NULL;
-
-    if (adsr_length > 0) {
-        //todo: calloc
-        attackArray = malloc(sizeof(float) * adsr_length);
-        size_t attack_length = attack.sample_count < adsr_length
-                ? attack.sample_count
-                : adsr_length;
-        
-        memcpy(attackArray, attack.samples, attack_length);
-        //todo: calloc
-        releaseArray = malloc(sizeof(float) * adsr_length);
-        memcpy(releaseArray, attackArray, attack_length);
-        reverse_array(releaseArray, 0, adsr_length);
-    }
-    */
-
-    // if (samples.sample_count > 1024) {
-    //     samples.sample_count = 1024;
-    // }
-    // //todo: move to somewhere
-    // for (size_t i = 0; i < 1024; i++) {
-    //     synth_sound.samples[i] = 0.0f;
-    // }
-
-    // for (size_t i = 0; i < samples.sample_count; i++) {
-    //     synth_sound.samples[i] = output[i];
-    // }
-    // synth_sound.sample_count = samples.sample_count;
-
-
-    // return zipped array
-    SynthSound res = {
-        .samples = output,
-        .sample_count = samples.sample_count
-    };
-
-    return res;
-}
-
-/*
-static SynthSound get_attack_samples() {
-    float attack_time = 0.001 * ATTACK_MS;
-    size_t sample_count = (size_t)(attack_time * SAMPLE_RATE);
-    float* attack = malloc(sizeof(float) * sample_count);
-    float samples_to_rise = SAMPLE_RATE * attack_time;
-    float rising_delta = 1.0 / samples_to_rise;
-    float i = 0.0;
-
-    for (int j = 0; j < sample_count; j++) {
-        i += rising_delta;
-        attack[j] = fmin(i, 1.0);
-    }
-
-    SynthSound res = {
-        .samples = attack,
-        .sample_count = sample_count
-    };
-
-    return res;
-}
-*/
-
 //------------------------------------------------------------------------------------
 // Synth
 //------------------------------------------------------------------------------------
@@ -435,80 +101,7 @@ SynthSound get_note_sound(Note input) {
     int semitone_shift = get_semitone_shift(input.name);
     return note(semitone_shift, length);
 }
-
+//-------------------------------------------------------
-
-//------------------------------------------------------------------------------------
-// Wav File 
-//------------------------------------------------------------------------------------
-
-static uint16_t toInt16Sample(float sample) {
-    return (uint16_t)(sample * 32767.f);
-}
-
-static void write_file(char* filename, void* data, int size) {
-    FILE* fp = fopen(filename, "wb");  // open file for writing in binary mode
-    if (fp == NULL) {
-        fprintf(stderr, "Cannot open file: %s\n", filename);
-        exit(1);
-    }
-
-    fwrite(data, size, 1, fp);  // write data to file
-
-    fclose(fp);  // close file
-}
-
-void pack(uint16_t* d, size_t length) {
-    size_t dataLength = length * 2;
-
-    int bytesPerSample = 2;
-    int byteRate = SAMPLE_RATE * bytesPerSample;
-
-    size_t fileSize = 36 + dataLength;
-
-    uint8_t* buffer = (uint8_t*)malloc(fileSize);
-
-    int i = 0;
-
-    // RIFF header
-    memcpy(buffer + i, "RIFF", 4);
-    i += 4;
-    memcpy(buffer + i, &fileSize, 4);
-    i += 4;
-    memcpy(buffer + i, "WAVE", 4);
-    i += 4;
-
-    // fmt subchunk
-    memcpy(buffer + i, "fmt ", 4);
-    i += 4;
-    int fmtSize = 16;
-    memcpy(buffer + i, &fmtSize, 4);
-    i += 4;
-    uint16_t audioFormat = 1;
-    memcpy(buffer + i, &audioFormat, 2);
-    i += 2;
-    uint16_t numChannels = 1;
-    memcpy(buffer + i, &numChannels, 2);
-    i += 2;
-    int sampleRate = (int)SAMPLE_RATE;
-    memcpy(buffer + i, &sampleRate, 4);
-    i += 4;
-    memcpy(buffer + i, &byteRate, 4);
-    i += 4;
-    memcpy(buffer + i, &bytesPerSample, 2);
-    i += 2;
-    int bitsPerSample = bytesPerSample * 8;
-    memcpy(buffer + i, &bitsPerSample, 2);
-    i += 2;
-
-    // data subchunk
-    memcpy(buffer + i, "data", 4);
-    i += 4;
-    memcpy(buffer + i, &dataLength, 4);
-    i += 4;
-    memcpy(buffer + i, d, dataLength);
-
-    write_file("output.wav", buffer, fileSize);
-}
 
 size_t detect_note_pressed(Note* note) {
     size_t is_pressed = 0;
@@ -544,42 +137,6 @@ size_t detect_note_pressed(Note* note) {
     return is_pressed;
 }
 
-//------------------------------------------------------------------------------------
-// UI
-//------------------------------------------------------------------------------------
-/*
-int get_zero_crossing(SynthSound* sound) {
-    int zero_crossing_index = 0;
-    for (size_t i = 1; i < sound->sample_count; i++)
-    {
-        if (sound->samples[i] >= 0.0f && sound->samples[i-1] < 0.0f) // zero-crossing
-        {
-            zero_crossing_index = i;
-            break;
-        }
-    }
-    return zero_crossing_index;
-}
-
-Vector2* GetVisualSignal(SynthSound* sound, int zero_crossing_index)
-{
-    const int signal_amp = 300;
-    
-    Vector2* signal_points = malloc(sizeof(Vector2) * STREAM_BUFFER_SIZE);
-    
-    const float screen_vertical_midpoint = (WINDOW_HEIGHT/2);
-    for (size_t point_idx = 0; point_idx < sound->sample_count; point_idx++)
-    {
-        const int signal_idx = (point_idx + zero_crossing_index) % STREAM_BUFFER_SIZE;
-        signal_points[point_idx].x = (float)point_idx + WINDOW_WIDTH;
-        signal_points[point_idx].y = screen_vertical_midpoint + (int)(sound->samples[signal_idx] * 300);
-    }
-
-    return signal_points;
-}
-
-*/
-
 //------------------------------------------------------------------------------------
 // Main
 //------------------------------------------------------------------------------------
@@ -604,7 +161,7 @@ int main(int argc, char **argv) {
     InitAudioDevice();
     SetMasterVolume(SYNTH_VOLUME);
     SetAudioStreamBufferSizeDefault(STREAM_BUFFER_SIZE);
-    AudioStream synth_stream = LoadAudioStream(SAMPLE_RATE, sizeof(float) * 8, 1);//float*8
+    AudioStream synth_stream = LoadAudioStream(SAMPLE_RATE, sizeof(float) * 8, 1);
     SetAudioStreamVolume(synth_stream, 0.5f);
 
     PlayAudioStream(synth_stream);
@@ -670,10 +227,6 @@ int main(int argc, char **argv) {
         BeginDrawing();
  
             ClearBackground(RAYWHITE);
-            // int zero_crossing = get_zero_crossing(&sound);
-            // Vector2* visual_signal = GetVisualSignal(&sound, zero_crossing);
-            // DrawLineStrip(visual_signal, STREAM_BUFFER_SIZE - zero_crossing, RED);
- 
             DrawText("Congrats! You created your first window!", 190, 200, 20, LIGHTGRAY);
             DrawFPS(0,0);
  

oscillator.c

@@ -0,0 +1,153 @@
+#include "oscillator.h"
+#include "settings.h"
+#include "math.h"
+#include "stdlib.h"
+
+static SynthSound get_init_samples(float duration) {
+    size_t sample_count = (size_t)(duration * SAMPLE_RATE);
+    float* samples = malloc(sizeof(float) * sample_count);
+
+    for (double i = 0.0; i < duration * SAMPLE_RATE; i++) {
+        samples[(int)i] = i;
+    }
+
+    SynthSound res = {
+        .samples = samples,
+        .sample_count = sample_count
+    };
+
+    return res;
+}
+
+static float pos(float hz, float x) {
+    return fmodf(hz * x / SAMPLE_RATE, 1);
+}
+
+static float sineosc(float hz, float x) {
+    return sinf(x * (2.f * SYNTH_PI * hz / SAMPLE_RATE));
+}
+
+static float sign(float v) {
+    return (v > 0.0) ? 1.f : -1.f;
+}
+
+static float squareosc(float hz, float x) {
+    return sign(sineosc(hz, x));
+}
+
+static float triangleosc(float hz, float x) {
+    return 1.f - fabsf(pos(hz, x) - 0.5f) * 4.f;
+}
+
+static float sawosc(float hz, float x) {
+    return pos(hz, x) * 2.f - 1.f;
+}
+
+float multiosc(OscillatorGenerationParameter param) {
+    float osc_sample = 0.f;
+    for (size_t i = 0; i < param.oscillators.count; i++) {
+        OscillatorParameter osc = param.oscillators.array[i];
+        switch (osc.osc) {
+            case Sine:
+                osc_sample += sineosc(osc.freq, param.sample);
+                break;
+            case Triangle:
+                osc_sample += triangleosc(osc.freq, param.sample);
+                break;
+            case Square:
+                osc_sample += squareosc(osc.freq, param.sample);
+                break;
+            case Saw:
+                osc_sample += sawosc(osc.freq, param.sample);
+                break;
+        }
+    }
+
+    return osc_sample;
+}
+
+SynthSound freq(float duration, OscillatorParameterList osc) {
+    SynthSound samples = get_init_samples(duration);
+    // SynthSound attack = get_attack_samples();
+
+    float* output = malloc(sizeof(float) * samples.sample_count);
+    for (int i = 0; i < samples.sample_count; i++) {
+        float sample = samples.samples[i];
+        OscillatorGenerationParameter param = {
+            .oscillators = osc,
+            .sample = sample
+        };
+        output[i] = multiosc(param) * VOLUME;
+    }
+
+    // create attack and release
+    /*
+        let adsrLength = Seq.length output
+        let attackArray = attack |> Seq.take adsrLength
+        let release = Seq.rev attackArray
+    */
+    /*
+     todo: I will change the ADSR approach to an explicit ADSR module(with it's own state)
+    size_t adsr_length = samples.sample_count;
+    float *attackArray = NULL, *releaseArray = NULL;
+
+    if (adsr_length > 0) {
+        //todo: calloc
+        attackArray = malloc(sizeof(float) * adsr_length);
+        size_t attack_length = attack.sample_count < adsr_length
+                ? attack.sample_count
+                : adsr_length;
+        
+        memcpy(attackArray, attack.samples, attack_length);
+        //todo: calloc
+        releaseArray = malloc(sizeof(float) * adsr_length);
+        memcpy(releaseArray, attackArray, attack_length);
+        reverse_array(releaseArray, 0, adsr_length);
+    }
+    */
+
+    // if (samples.sample_count > 1024) {
+    //     samples.sample_count = 1024;
+    // }
+    // //todo: move to somewhere
+    // for (size_t i = 0; i < 1024; i++) {
+    //     synth_sound.samples[i] = 0.0f;
+    // }
+
+    // for (size_t i = 0; i < samples.sample_count; i++) {
+    //     synth_sound.samples[i] = output[i];
+    // }
+    // synth_sound.sample_count = samples.sample_count;
+
+
+    // return zipped array
+    SynthSound res = {
+        .samples = output,
+        .sample_count = samples.sample_count
+    };
+
+    return res;
+}
+
+/*
+static SynthSound get_attack_samples() {
+    float attack_time = 0.001 * ATTACK_MS;
+    size_t sample_count = (size_t)(attack_time * SAMPLE_RATE);
+    float* attack = malloc(sizeof(float) * sample_count);
+    float samples_to_rise = SAMPLE_RATE * attack_time;
+    float rising_delta = 1.0 / samples_to_rise;
+    float i = 0.0;
+
+    for (int j = 0; j < sample_count; j++) {
+        i += rising_delta;
+        attack[j] = fmin(i, 1.0);
+    }
+
+    SynthSound res = {
+        .samples = attack,
+        .sample_count = sample_count
+    };
+
+    return res;
+}
+*/

oscillator.h

@@ -0,0 +1,33 @@
+#ifndef OSCILLATOR_H
+#define OSCILLATOR_H
+
+#include "utils.h"
+
+typedef enum {
+    Sine,
+    Triangle,
+    Saw,
+    Square
+} OscillatorType;
+
+typedef struct OscillatorParameter {
+    OscillatorType osc;
+    float freq;
+} OscillatorParameter;
+
+typedef struct OscillatorParameterList {
+    OscillatorParameter* array;
+    size_t count;
+} OscillatorParameterList;
+
+typedef struct OscillatorGenerationParameter {
+    OscillatorParameterList oscillators;
+    float sample;
+} OscillatorGenerationParameter;
+
+float multiosc(OscillatorGenerationParameter param);
+SynthSound freq(float duration, OscillatorParameterList osc);
+
+
+
+#endif

ring_buffer.c

@@ -0,0 +1,99 @@
+#include "ring_buffer.h"
+#include "utils.h"
+
+RingBuffer ring_buffer_init(size_t buffer_size) {
+    RingBuffer buffer = {
+        .items = calloc(buffer_size, sizeof(float)),
+        .head = 0,
+        .tail = 0,
+        .is_full = 0,
+        .is_empty = 1,
+        .size = buffer_size
+    };
+
+    return buffer;
+}
+
+void ring_buffer_reset(RingBuffer* me) {
+    me->head = 0;
+    me->tail = 0;
+    me->is_full = 0;
+}
+
+// +
+static void advance_pointer(RingBuffer* me) {
+    if(me->is_full) {
+        me->tail++;
+		if (me->tail == me->size) { 
+			me->tail = 0;
+		}
+	}
+    me->head++;
+	if (me->head == me->size) { 
+		me->head = 0;
+	}
+    size_t is_full = me->head == me->tail ? 1 : 0;
+	me->is_full = is_full;
+}
+
+// -
+static void retreat_pointer(RingBuffer* me) {
+	me->is_full = 0;
+    me->tail++;
+	if (me->tail == me->size) { 
+		me->tail = 0;
+	}
+}
+
+void ring_buffer_write(RingBuffer* buffer, float* data, size_t count) {
+    if (buffer->is_full || buffer->head + count > buffer->size) {
+        write_log("[WARN] Trying to overfill the ring buffer: \n\tIsFull:%d\n\tHead:%zu\n\tCount:%zu\n\t", 
+            buffer->is_full,
+            buffer->head, 
+            count);
+        return;
+    }
+    buffer->is_empty = 0;
+
+    for (size_t i = 0; i < count; i++) {
+        buffer->items[buffer->head] = data[i];
+        advance_pointer(buffer);
+    }
+    //me->is_empty = is_full && (me->head == me->tail);
+}
+
+int ring_buffer_read(RingBuffer* buffer, float* output, size_t count) {
+    if (buffer->is_empty) {
+        write_log("[WARN] Trying to read empty buffer");
+        return 0;
+    }
+
+    for (size_t i = 0; i < count; i++) {
+        output[i] = buffer->items[buffer->tail];
+        retreat_pointer(buffer);
+    }
+    buffer->is_empty = !buffer->is_full && (buffer->head == buffer->tail);
+    return 1;
+}
+
+size_t ring_buffer_size(RingBuffer* buffer) {
+	size_t size = buffer->size;
+	if(!buffer->is_full) {
+		if(buffer->head >= buffer->tail) {
+			size = (buffer->head - buffer->tail);
+		}
+		else {
+			size = (buffer->size + buffer->head - buffer->tail);
+		}
+	}
+
+	return size;
+}
+
+void ring_buffer_print(RingBuffer* me) {
+    write_log("[INFO] The ring buffer: \n\tIsFull:%d\n\tIsEmpty:%d\n\tHead:%zu\n\tTail:%zu\n\t", 
+                me->is_full, 
+                me->is_empty, 
+                me->head, 
+                me->tail);
+}

ring_buffer.h

@@ -0,0 +1,22 @@
+#ifndef RING_BUFFER_H
+#define RING_BUFFER_H
+
+#include "stdlib.h"
+
+typedef struct RingBuffer {
+    float* items;
+    size_t head;
+    size_t tail;
+    int is_full;
+    int is_empty;
+    size_t size;
+} RingBuffer;
+
+RingBuffer ring_buffer_init(size_t buffer_size);
+void ring_buffer_reset(RingBuffer* me);
+void ring_buffer_write(RingBuffer* buffer, float* data, size_t count);
+int ring_buffer_read(RingBuffer* buffer, float* output, size_t count);
+size_t ring_buffer_size(RingBuffer* buffer);
+void ring_buffer_print(RingBuffer* me);
+
+#endif

settings.h

@@ -0,0 +1,18 @@
+#ifndef SETTINGS_H
+#define SETTINGS_H
+
+#define SAMPLE_RATE 48000.f
+#define BPM 120.f
+#define BEAT_DURATION 60.f/BPM
+#define PITCH_STANDARD 440.f
+#define VOLUME 0.5f
+#define ATTACK_MS 100.f
+#define STREAM_BUFFER_SIZE 4096
+
+#define SYNTH_PI 3.1415926535f
+#define SYNTH_VOLUME 0.5f
+
+#define WINDOW_WIDTH 640
+#define WINDOW_HEIGHT 480
+
+#endif

utils.c

@@ -0,0 +1,30 @@
+#include "utils.h"
+#include "stdlib.h"
+#include "string.h"
+
+// frees the original sounds
+SynthSound concat_sounds(SynthSound* sounds, size_t count) {
+    size_t total_count = 0;
+    for (size_t i = 0; i < count; i++) {
+        total_count += sounds[i].sample_count;
+    }
+    // array to hold the result
+    float* total = malloc(total_count * sizeof(float));
+
+    size_t current_count = 0;
+    for (size_t i = 0; i < count; i++) {
+        memcpy(total + current_count,
+            sounds[i].samples,
+            sounds[i].sample_count * sizeof(float));
+        current_count += sounds[i].sample_count;
+
+        free(sounds[i].samples);
+    }
+
+    SynthSound result = {
+        .samples = total,
+        .sample_count = total_count
+    };
+
+    return result;
+}

utils.h

@@ -0,0 +1,22 @@
+#ifndef UTILS_H
+#define UTILS_H
+
+#include "stdio.h"
+
+#define write_log(format,args...) do { \
+        printf(format, ## args); \
+    } while(0)
+
+//------------------------------------------------------------------------------------
+// General SynthSound
+//------------------------------------------------------------------------------------
+
+typedef struct SynthSound {
+    float* samples;
+    size_t sample_count;
+} SynthSound;
+
+// frees the original sounds
+SynthSound concat_sounds(SynthSound* sounds, size_t count);
+
+#endif