Init

2025-04-23 22:55:22 +02:00
commit 8fd5f1cf1e
8 changed files with 565 additions and 0 deletions
--- a/util/audio.c
+++ b/util/audio.c
@@ -0,0 +1,50 @@
+/*
+// Created by bruno on 16.2.2025.
+*/
+
+#include "audio.h"
+
+AudioData audioData;
+
+void audio_callback(void *userdata, Uint8 *stream, int len) {
+    AudioData *audio = (AudioData *) userdata;
+    int samples = len / sizeof(float);
+
+    for (int i = 0; i < samples; i++) {
+        float mix = 0.0f;
+        int activeVoices = 0;
+
+        for (int v = 0; v < NUM_SYNTH_VOICES; v++) {
+            SynthVoice *voice = &audio->synthVoices[v];
+            if (voice->volume == 0 || voice->frequency == 0) continue;
+
+            float sample = 0.0f;
+            float t = (float) voice->phase / 255.0f * 2.0f - 1.0f;
+
+            switch (voice->waveform) {
+                default:
+                case WAVE_SINE:
+                    sample = sinf(voice->phase * 2.0f * M_PI / 256.0f);
+                    break;
+                case WAVE_SQUARE:
+                    sample = (t >= 0.0f) ? 1.0f : -1.0f;
+                    break;
+                case WAVE_SAWTOOTH:
+                    sample = t;
+                    break;
+                case WAVE_TRIANGLE:
+                    sample = (t < 0) ? -t : t;
+                    break;
+                case WAVE_NOISE:
+                    sample = ((float) rand() / RAND_MAX) * 2.0f - 1.0f;
+                    break;
+            }
+
+            voice->phase += (uint8_t) ((voice->frequency * 256) / SAMPLE_RATE);
+            mix += sample * (voice->volume / 255.0f);
+            activeVoices++;
+        }
+
+        ((float *) stream)[i] = (activeVoices > 0) ? mix / activeVoices : 0.0f;
+    }
+}