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audio.c — ALSA sound engine for ac-native// Dedicated audio thread with multi-voice synthesis, envelopes, and effects.
#define _GNU_SOURCE // pthread_setaffinity_np, CPU_SET, cpu_set_t
#include "audio.h"#include <stdio.h>#include <stdlib.h>#include <string.h>#include <math.h>#include <time.h>#include <limits.h>#include <dirent.h>#include <sys/stat.h> // S_ISDIR for piano_bank_dir() probe#include <unistd.h>#include <sched.h>#include <alsa/asoundlib.h>#include <alsa/use-case.h>
// Defined in ac-native.c — writes to USB log and stderr.extern void ac_log(const char *fmt, ...);
// Forward declarationsstatic int read_system_volume_card(int card);
// qsort comparator for AC_LATENCY_BENCH percentile computation.static int bench_cmp_long(const void *a, const void *b) { long la = *(const long *)a, lb = *(const long *)b; return (la > lb) - (la < lb);}
// ============================================================// Note frequency table (octave 0 base frequencies)// ============================================================
static const struct { const char *name; double freq; } note_table[] = { {"c", 16.3516}, {"cs", 17.3239}, {"db", 17.3239}, {"d", 18.3540}, {"ds", 19.4454}, {"eb", 19.4454}, {"e", 20.6017}, {"f", 21.8268}, {"fs", 23.1247}, {"gb", 23.1247}, {"g", 24.4997}, {"gs", 25.9565}, {"ab", 25.9565}, {"a", 27.5000}, {"as", 29.1352}, {"bb", 29.1352}, {"b", 30.8677},};#define NOTE_TABLE_SIZE (sizeof(note_table) / sizeof(note_table[0]))
double audio_note_to_freq(const char *note) { if (!note || !*note) return 440.0;
// Try parsing as a number first char *end; double d = strtod(note, &end); if (end != note && *end == '\0') return d;
// Parse note string: "C4", "4C#", "C#4", "5A", etc. int octave = 4; char name_buf[8] = {0}; int ni = 0; const char *p = note;
// Check if starts with digit (octave prefix: "4C#") if (*p >= '0' && *p <= '9') { octave = *p - '0'; p++; }
// Read note name while (*p && ni < 3) { char ch = *p; if (ch >= 'A' && ch <= 'G') ch += 32; // lowercase if ((ch >= 'a' && ch <= 'g') || ch == '#' || ch == 's' || ch == 'b') { // Map 'f' for flat and '#' for sharp if (ch == '#') { name_buf[ni++] = 's'; } else { name_buf[ni++] = ch; } p++; } else break; } name_buf[ni] = '\0';
// Trailing octave number if (*p >= '0' && *p <= '9') { octave = *p - '0'; }
// Lookup base frequency double base = 440.0; // fallback for (int i = 0; i < (int)NOTE_TABLE_SIZE; i++) { if (strcmp(name_buf, note_table[i].name) == 0) { base = note_table[i].freq; break; } }
return base * pow(2.0, octave);}
// ============================================================// Oscillator sample generation// ============================================================
static inline uint32_t xorshift32(uint32_t *state) { uint32_t x = *state; x ^= x << 13; x ^= x >> 17; x ^= x << 5; *state = x; return x;}
static inline double clampd(double x, double lo, double hi) { if (x < lo) return lo; if (x > hi) return hi; return x;}
// The sine wavetable + bounded per-note stochasticism helpers that used to// live here moved into the standalone gm_synth module (gm_synth.c). The GM// voices own their own copies; this engine only drives them via// gm_voice_init()/gm_voice_render(). The global organic knob is set through// gm_set_organic() (see audio_set_organic below).
static inline double compute_envelope(ACVoice *v) { double env = 1.0;
// Attack ramp if (v->attack > 0.0 && v->elapsed < v->attack) { env = v->elapsed / v->attack; }
// Decay (near end of duration) if (!isinf(v->duration) && v->decay > 0.0) { double decay_start = v->duration - v->decay; if (decay_start < 0.0) decay_start = 0.0; if (v->elapsed > decay_start) { double decay_progress = (v->elapsed - decay_start) / v->decay; if (decay_progress > 1.0) decay_progress = 1.0; env *= (1.0 - decay_progress); } }
return env;}
// Fractional-delay read from a ring buffer. `delay` is in samples, allows// non-integer values via linear interpolation between adjacent samples.// Returns the sample `delay` positions behind the write cursor.static inline double whistle_frac_read(const float *buf, int N, int w, double delay) { if (delay < 0.0) delay = 0.0; if (delay > (double)(N - 2)) delay = (double)(N - 2); double rd = (double)w - delay; while (rd < 0.0) rd += (double)N; int i0 = (int)rd; int i1 = (i0 + 1) % N; double f = rd - (double)i0; return (double)buf[i0] * (1.0 - f) + (double)buf[i1] * f;}
// Cook/STK digital waveguide flute model.// The signal flow (see reports/research for full derivation)://// breath ──► (+) ──► jetDelay ──► NL(x*(x*x-1)) ──► dcBlock ──► (+) ──► boreDelay ──┬──► out// ▲ ▲ │// │ −jetRefl·temp │ +endRefl·temp │// │ │ │// └───────── 1-pole LPF ◄───────────────────────────┴──────────────────┘//// The BORE delay line (length = SR/freq) is the primary resonator. Its// closed-loop feedback generates ALL harmonics automatically via comb// filtering — the delay line is inherently a periodic waveguide that// sustains exactly at integer multiples of its natural pitch.//// The JET delay (length ≈ 0.32 × bore) models the air jet's travel time// across the embouchure hole. The cubic nonlinearity x*(x*x-1) has// negative-slope region at x=0 which makes it a LIMIT-CYCLE GENERATOR —// it converts steady DC breath pressure into sustained oscillation.// This is qualitatively different from tanh, which is monotonic and// can only saturate.//// The 1-pole LPF in the loop models bore losses (viscothermal damping)// so the tone darkens as harmonics decay faster than the fundamental.//// The DC blocker after the NL removes the bias the cubic would pump// into the bore loop, which would otherwise drive it into clipping.static inline double generate_whistle_sample(ACVoice *v, double sample_rate) { double env = compute_envelope(v); // Breath envelope — DC pressure component + noise modulation + vibrato. // CRITICAL: the DC component is what drives the nonlinearity into // self-oscillation. Without a steady DC term, noise alone cannot // sustain the limit cycle. double breath_target = 0.18 + 0.82 * sqrt(env); double breath_slew = env > v->whistle_breath ? 0.012 : 0.003; v->whistle_breath += (breath_target - v->whistle_breath) * breath_slew;
// Vibrato LFO — ~5 Hz, small depth v->whistle_vibrato_phase += 5.0 / sample_rate; if (v->whistle_vibrato_phase >= 1.0) v->whistle_vibrato_phase -= 1.0; double vibrato = sin(2.0 * M_PI * v->whistle_vibrato_phase) * 0.03;
// Breath noise — multiplicatively modulates the DC breath pressure. // Low gain so the noise rides on top of the steady breath instead of // replacing it. Attack phase gets slightly more chiff. double white = ((double)xorshift32(&v->noise_seed) / (double)UINT32_MAX) * 2.0 - 1.0; double onset = 1.0 - env; double noise_gain = 0.08 + 0.05 * onset; double breath = v->whistle_breath * (1.0 + noise_gain * white + vibrato);
// Bore and jet delay lengths — bore = SR/freq (one wavelength), // jet = 0.32 × bore (Cook's flute ratio; 0.45 for pennywhistle, // 0.5 for ocarina). Clamp to the delay buffer sizes. // Allow the full notepat pitch range — C1 ≈ 33Hz, so clamp at 30Hz // so we don't lose the bottom octave. On sample rates where SR/freq // exceeds the bore buffer (BORE_N=2048, fine at 48kHz; caps around // 94Hz at 192kHz), the bore_delay clampd below pins the delay to the // buffer size — the worst case is that very low notes play slightly // sharper than requested on 192kHz hardware. Still better than the // previous 110Hz hard-clamp which silenced every low octave. double freq = clampd(v->frequency, 30.0, sample_rate * 0.20); // Bore length. NOTE: "one wavelength = sr/freq" makes THIS jet+reflection // loop lock to a higher register and sound a PERFECT FIFTH (×1.5) sharp on // every note — measured consistently across 110–880 Hz (the "very high // pitched" whistle). The loop's fundamental sits at 1.5× the sr/bore_delay // frequency, so the bore must be 1.5 wavelengths long for the played pitch // to land on the requested note. freq×2/3 → bore_delay = 1.5·sr/freq. // Verified: retuned, output tracks the requested pitch to ±0.1 semitone // over the whistle's musical range. double bore_delay = sample_rate / (freq * (2.0 / 3.0)); double jet_delay = bore_delay * 0.32; // Cap to buffer sizes with safety margin const int BORE_N = 2048; const int JET_N = 512; if (bore_delay > (double)(BORE_N - 2)) bore_delay = (double)(BORE_N - 2); if (jet_delay > (double)(JET_N - 2)) jet_delay = (double)(JET_N - 2);
// Read bore output and apply 1-pole loop LPF (models bore damping). // 0.35/0.65 coefficients give ~0.65 DC gain — closes the loop just // under unity so it sustains but doesn't blow up. The LPF rolls off // high harmonics so the tone darkens naturally, unlike a biquad // which would over-narrow the spectrum. double bore_out = whistle_frac_read(v->whistle_bore_buf, BORE_N, v->whistle_bore_w, bore_delay); v->whistle_lp1 = 0.35 * (-bore_out) + 0.65 * v->whistle_lp1; double temp = v->whistle_lp1;
// Jet drive: breath pressure minus jet reflection from bore feedback double jet_refl = 0.5; double end_refl = 0.5; double pd = breath - jet_refl * temp;
// Write to jet delay, read back with fractional delay v->whistle_jet_buf[v->whistle_jet_w] = (float)pd; v->whistle_jet_w = (v->whistle_jet_w + 1) % JET_N; pd = whistle_frac_read(v->whistle_jet_buf, JET_N, v->whistle_jet_w, jet_delay);
// THE CUBIC NONLINEARITY — y = x*(x*x - 1). Negative slope at x=0 // creates a limit-cycle generator. This is the secret sauce that // makes the tone WHISTLE instead of being filtered noise. pd = pd * (pd * pd - 1.0); if (pd > 1.0) pd = 1.0; if (pd < -1.0) pd = -1.0;
// 1-pole DC blocker — removes the bias the cubic pumps into the loop. // y[n] = x[n] - x[n-1] + 0.995*y[n-1] double y = pd - v->whistle_hp_x1 + 0.995 * v->whistle_hp_y1; v->whistle_hp_x1 = pd; v->whistle_hp_y1 = y;
// Close the bore loop: combine the NL-filtered jet output with the // end reflection from the bore delay. double into_bore = y + end_refl * temp; v->whistle_bore_buf[v->whistle_bore_w] = (float)into_bore; v->whistle_bore_w = (v->whistle_bore_w + 1) % BORE_N;
// Output is a tap off the bore loop. 0.3 gain matches STK Flute. return 0.3 * into_bore;}
// ============================================================// Harp synthesis — Karplus-Strong plucked string// ============================================================//// The canonical digital plucked-string model. Parallels the whistle's// waveguide flute but for a *struck/plucked* resonator://// pluck noise ──► delay line (N = sr/freq) ──┬──► out// ▲ │// │ ▼// └── × S ◄── avg[x,x₋₁] (H(z) = 0.5 + 0.5·z⁻¹)//// References:// [1] Karplus, K. & Strong, A. (1983). "Digital Synthesis of Plucked-// String and Drum Timbres," Computer Music Journal 7(2), 43-55.// The original algorithm: delay line seeded with noise, two-point// moving-average filter in the feedback loop.// [2] Jaffe, D.A. & Smith, J.O. (1983). "Extensions of the Karplus-// Strong Plucked-String Algorithm," Computer Music Journal 7(2),// 56-69. Introduces the stretch factor S for decay control,// pitch tuning, dynamics, and brightness.// [3] Smith, J.O. "Physical Audio Signal Processing," CCRMA Stanford// (online book) — https://ccrma.stanford.edu/~jos/pasp/Karplus_Strong_Algorithm.html// Later showed K-S is a special case of digital waveguide modeling.//// Algorithm per sample:// 1. Read from the delay line at (w − N) — one wavelength behind.// 2. Apply the two-point moving-average damping filter:// filtered = 0.5 · (delayed + previous_delayed)// Unity DC gain, cosine rolloff; higher harmonics decay faster// than the fundamental — the spectral signature of real strings.// 3. Multiply by stretch factor S (<1) to control overall decay time.// (Jaffe & Smith 1983: stretch factor decouples decay from N so// high and low notes have usable ringing.)// 4. Write back to the delay line.//// Initial pluck: the delay line is pre-filled with a single wavelength// of pre-smoothed white noise. Smoothing the noise once before injection// softens the initial transient (less "harsh pluck," more "nylon-ish").static inline double generate_harp_sample(ACVoice *v, double sample_rate) { double env = compute_envelope(v);
double freq = clampd(v->frequency, 50.0, sample_rate * 0.20); double string_delay = sample_rate / freq; const int STRING_N = 2048; if (string_delay > (double)(STRING_N - 2)) string_delay = (double)(STRING_N - 2); if (string_delay < 2.0) string_delay = 2.0;
// Read delayed sample (one wavelength ago) with fractional interpolation. // Reuses whistle_bore_buf since a voice is one wave type at a time. double delayed = whistle_frac_read(v->whistle_bore_buf, STRING_N, v->whistle_bore_w, string_delay);
// Two-point moving-average damping filter (Karplus & Strong 1983). // y[n] = 0.5 · (x[n] + x[n−1]). Zero multiplications in the original — // a shift-and-add. We keep the 0.5 constant for clarity. double filtered = 0.5 * (delayed + v->harp_lp1); v->harp_lp1 = delayed;
// Stretch factor S (Jaffe-Smith EKS). S < 1 makes the circulating // pattern decay exponentially. With the two-point LPF ≈ unity at DC, // the per-cycle loss is dominated by S: amplitude ≈ S^(f·t) per second. // S = 0.9985 gives T60 ≈ 15s at 440Hz — long sustain like a real // pedal harp letting the string ring out. // // "Short pluck" variant — triggered by a FINITE SHORT duration on the // voice. Notepat uses duration=Infinity for sustained harp notes and // duration≈0.4 for Shift+letter staccato plucks. The previous // implementation keyed on decay<0.2 but that collided with the // default decay mode (0.1s), so every harp press got short-stretch // and shift did nothing audible. double stretch = (!isinf(v->duration) && v->duration > 0.0 && v->duration < 1.0) ? 0.990 : 0.9985; double decayed = filtered * stretch;
// Write back to close the delay loop. v->whistle_bore_buf[v->whistle_bore_w] = (float)decayed; v->whistle_bore_w = (v->whistle_bore_w + 1) % STRING_N;
// Output gain — Karplus-Strong's circulating amplitude is heavily // attenuated by the LPF + stretch each cycle, so raw output is much // quieter than sine/square at the same `volume`. Boost by 2.5× so a // plucked note feels comparable in loudness to other wave types. // Envelope still controls key-up fade; attack is instantaneous (the // initial noise burst IS the pluck). return 2.5 * decayed * env;}
// ============================================================// Piano synthesis — modal additive grand piano with stretched partials// ============================================================//// Algorithm (Bank/Välimäki modal-additive school, simplified for embedded// per-sample synthesis at 192kHz). For each note we run ~10 sine partials// at stretched-harmonic frequencies://// f_n = n · f0 · sqrt(1 + B · n²) (Fletcher-Rossing eq. 12.12)//// where B is the inharmonicity coefficient — for a real grand B ranges// from ~5e-5 at A0 (long bass strings) to ~5e-3 at C8 (short, stiff// treble). We scale B with f0 so high notes are noticeably stretched and// bass notes stay nearly harmonic.//// The signature "ringing" piano character comes from this stretching:// the 8th partial isn't at 8·f0, it's a few cents sharper. When the// partials sound together with their natural beating, the ear hears a// real grand piano instead of a pure-harmonic sawtooth-ish "organ."//// Each partial decays exponentially with its own T60 (high partials die// faster — measured behavior of struck strings: damping ~ω². See Weinreich// 1977, "Coupled piano strings"). A real grand decays slowly (T60 ~ 8s// for the fundamental of A4), so the partial decays continue as long as// the voice is held.//// Three slightly mistuned "phantom" fundamental partials at f0±~0.6 Hz// produce the inter-string beating of a 3-string unison choir without// the cost of actually running 3 full string models. The beating is// what makes a piano sound like a piano and not a synth bell.//// Hammer thump: a short white-noise burst, low-pass filtered through a// 1-pole LPF (~3kHz cutoff) with ~5ms exponential decay. This is the// "felt + wood + soundboard" attack transient — Smith & Van Duyne's// "commuted synthesis" idea, collapsed into a cheap excitation since we// don't model the soundboard explicitly.//// References embedded above the piano fields in audio.h.// ============================================================// Piano sample bank — Salamander Grand Piano V3 (CC0)// ============================================================// Loaded once at audio_init from /samples/piano/<midi>.raw. Each .raw// file is a header-less stream of float32 mono samples at 48 kHz.// Filename convention: "<midi>.raw" where MIDI is the anchor pitch// (60 = C4 = 261.63 Hz). The pre-build script in// fedac/native/scripts/prep-piano-samples decimates the full SFZ to// these anchor pitches every 3 semitones (matching Salamander's own// anchor density: C, D#, F#, A across each octave).//// Voice playback: pick the nearest anchor by MIDI distance, set step =// 2^((target_midi - anchor_midi)/12) and read with fractional linear// interp. Up to ±1.5 semitones from any anchor → minor timbral artifact// from pitch shifting, well within psychoacoustic acceptance.typedef struct { int midi; // anchor MIDI note number int len; // sample count float *data; // mono float32, sample_rate = AUDIO_SAMPLE_RATE} PianoSample;#define PIANO_BANK_MAX 64static PianoSample piano_bank[PIANO_BANK_MAX];static int piano_bank_count = 0;
static const char *piano_bank_dir(void) { // Built into the initramfs by build-and-flash-initramfs.sh. Falls // back to a /mnt path so the same bank can live on the USB data // partition for OTA-2-style large-bank installations. static const char *paths[] = { "/samples/piano", "/mnt/samples/piano", NULL }; for (int i = 0; paths[i]; i++) { struct stat st; if (stat(paths[i], &st) == 0 && S_ISDIR(st.st_mode)) return paths[i]; } return NULL;}
// Parse "<midi>.raw" → midi int. Returns -1 on parse failure.static int parse_piano_filename(const char *name) { int n = 0; const char *p = name; while (*p >= '0' && *p <= '9') { n = n * 10 + (*p - '0'); p++; } if (p == name) return -1; if (strcmp(p, ".raw") != 0) return -1; if (n < 0 || n > 127) return -1; return n;}
void load_piano_bank(void) { piano_bank_count = 0; const char *dir_path = piano_bank_dir(); if (!dir_path) { ac_log("[piano-bank] no samples dir found — piano will be silent\n"); return; } DIR *dir = opendir(dir_path); if (!dir) { ac_log("[piano-bank] opendir failed: %s\n", dir_path); return; } struct dirent *ent; while ((ent = readdir(dir)) != NULL && piano_bank_count < PIANO_BANK_MAX) { if (ent->d_name[0] == '.') continue; int midi = parse_piano_filename(ent->d_name); if (midi < 0) continue; char path[512]; snprintf(path, sizeof(path), "%s/%s", dir_path, ent->d_name); FILE *fp = fopen(path, "rb"); if (!fp) continue; fseek(fp, 0, SEEK_END); long sz = ftell(fp); rewind(fp); if (sz <= 0 || sz % sizeof(float) != 0) { fclose(fp); continue; } int sample_count = (int)(sz / sizeof(float)); float *buf = malloc((size_t)sz); if (!buf) { fclose(fp); continue; } size_t rd = fread(buf, 1, (size_t)sz, fp); fclose(fp); if (rd != (size_t)sz) { free(buf); continue; } piano_bank[piano_bank_count].midi = midi; piano_bank[piano_bank_count].len = sample_count; piano_bank[piano_bank_count].data = buf; piano_bank_count++; } closedir(dir); ac_log("[piano-bank] loaded %d samples from %s\n", piano_bank_count, dir_path);}
// Pick the bank entry closest to the target MIDI note.static const PianoSample *pick_piano_anchor(int target_midi) { if (piano_bank_count == 0) return NULL; const PianoSample *best = &piano_bank[0]; int best_dist = abs(target_midi - best->midi); for (int i = 1; i < piano_bank_count; i++) { int d = abs(target_midi - piano_bank[i].midi); if (d < best_dist) { best_dist = d; best = &piano_bank[i]; } } return best;}
static inline double generate_piano_sample(ACVoice *v, double sample_rate) { (void)sample_rate; double env = compute_envelope(v);
if (!v->piano_sample_data || v->piano_sample_len <= 0) return 0.0;
double pos = v->piano_sample_pos; int idx = (int)pos; if (idx >= v->piano_sample_len - 1) { // Sample exhausted — note has run its natural decay length. return 0.0; } double frac = pos - (double)idx; double s0 = (double)v->piano_sample_data[idx]; double s1 = (double)v->piano_sample_data[idx + 1]; double s = (1.0 - frac) * s0 + frac * s1;
v->piano_sample_pos = pos + v->piano_sample_step;
return s * v->piano_sample_amp * env;}
// (Old K-S banded waveguide piano + earlier modal-additive synth both// removed in favor of the Salamander sample bank above. Search the git// history for "Karplus-Strong" or "Bank/Välimäki" if you need to compare.)
// ============================================================// GM synthesis library (modal piano / FM e-piano / extended Karplus-Strong /// modal bank / subtractive synth bass) was EXTRACTED to the standalone,// dependency-free gm_synth module (src/gm_synth.{h,c}) so it can compile + be// tested off-device (macOS, no ALSA) and later be shared into Menu Band. The// program tables, GMProgramParams, gm_voice_init(), the generators, and// gm_program_implemented() all live there now. This engine fills a per-voice// GMVoice (ACVoice.gm) at note-on and renders it via gm_voice_render().// ============================================================
// ============================================================// One-shot named-buffer bank (zoo / lasers / future kits)// ============================================================// Mirrors the piano bank above but indexed by string name and addressed// per-voice (each concurrent voice can play a different buffer). This// is what notepat's `zoo` and `lasers` kits route through — they trigger// pre-recorded one-shot files instead of synthesizing each animal/laser// from oscillators.//// File layout on disk: <bank_root>/<name>.raw — header-less float32// mono at AUDIO_SAMPLE_RATE. The pre-build scripts// (scripts/prep-zoo-samples.sh) generate these and check them into the// repo; build-and-flash-initramfs.sh copies them to /samples/<kit>/.//// At load time we scan both /samples/zoo and /samples/lasers (if// present) and merge into one flat name-keyed table. Names collide at// peril of last-write-wins — keep them unique across kits.typedef struct { char name[16]; // lowercase stem, NUL-terminated, max 15 chars int len; // sample count float *data; // mono float32 at AUDIO_SAMPLE_RATE} OneShotSample;#define ONESHOT_BANK_MAX 64static OneShotSample oneshot_bank[ONESHOT_BANK_MAX];static int oneshot_bank_count = 0;
typedef struct { int active; const OneShotSample *sample; // points into oneshot_bank double position; // fractional sample index double speed; // 1.0 = original pitch double volume; double pan; double fade; double fade_target; uint64_t id;} OneShotVoice;#define ONESHOT_MAX_VOICES 16static OneShotVoice oneshot_voices[ONESHOT_MAX_VOICES];static uint64_t oneshot_next_id = 1;static pthread_mutex_t oneshot_lock = PTHREAD_MUTEX_INITIALIZER;
// Lowercase-copy up to dst_max-1 chars. Returns dst.static char *oneshot_lowercase_copy(char *dst, size_t dst_max, const char *src) { size_t i = 0; for (; src[i] && i + 1 < dst_max; i++) { char c = src[i]; if (c >= 'A' && c <= 'Z') c = (char)(c - 'A' + 'a'); dst[i] = c; } dst[i] = '\0'; return dst;}
// Load any *.raw files from `dir_path` into oneshot_bank[]. Stops if// the bank fills (rare — 64 entries is plenty for two kits).static void load_oneshot_bank_dir(const char *dir_path) { DIR *dir = opendir(dir_path); if (!dir) return; struct dirent *ent; while ((ent = readdir(dir)) != NULL && oneshot_bank_count < ONESHOT_BANK_MAX) { if (ent->d_name[0] == '.') continue; size_t nlen = strlen(ent->d_name); if (nlen < 5 || strcmp(ent->d_name + nlen - 4, ".raw") != 0) continue;
char stem[32]; size_t stem_len = nlen - 4; if (stem_len >= sizeof(stem)) stem_len = sizeof(stem) - 1; memcpy(stem, ent->d_name, stem_len); stem[stem_len] = '\0';
char path[512]; snprintf(path, sizeof(path), "%s/%s", dir_path, ent->d_name); FILE *fp = fopen(path, "rb"); if (!fp) continue; fseek(fp, 0, SEEK_END); long sz = ftell(fp); rewind(fp); if (sz <= 0 || sz % (long)sizeof(float) != 0) { fclose(fp); continue; } int sample_count = (int)(sz / (long)sizeof(float)); float *buf = malloc((size_t)sz); if (!buf) { fclose(fp); continue; } size_t rd = fread(buf, 1, (size_t)sz, fp); fclose(fp); if (rd != (size_t)sz) { free(buf); continue; }
// If a sample by this name already exists, replace it (lasers // overrides zoo if names ever collide). Keeps bank flat. char lc_name[16]; oneshot_lowercase_copy(lc_name, sizeof(lc_name), stem); int slot = -1; for (int i = 0; i < oneshot_bank_count; i++) { if (strcmp(oneshot_bank[i].name, lc_name) == 0) { slot = i; break; } } if (slot < 0) { slot = oneshot_bank_count++; } else { free(oneshot_bank[slot].data); } strncpy(oneshot_bank[slot].name, lc_name, sizeof(oneshot_bank[slot].name) - 1); oneshot_bank[slot].name[sizeof(oneshot_bank[slot].name) - 1] = '\0'; oneshot_bank[slot].len = sample_count; oneshot_bank[slot].data = buf; } closedir(dir);}
void load_oneshot_bank(void) { oneshot_bank_count = 0; // Scan known kit dirs. /mnt fallback mirrors the piano bank pattern // so an OTA-2-style USB data partition can carry larger sample sets. static const char *paths[] = { "/samples/zoo", "/samples/lasers", "/mnt/samples/zoo", "/mnt/samples/lasers", NULL, }; for (int i = 0; paths[i]; i++) { struct stat st; if (stat(paths[i], &st) != 0 || !S_ISDIR(st.st_mode)) continue; load_oneshot_bank_dir(paths[i]); } if (oneshot_bank_count == 0) { ac_log("[oneshot-bank] no samples found — zoo/lasers will be silent\n"); return; } ac_log("[oneshot-bank] loaded %d samples\n", oneshot_bank_count);}
static const OneShotSample *find_oneshot(const char *name) { if (!name || !*name) return NULL; char lc[16]; oneshot_lowercase_copy(lc, sizeof(lc), name); for (int i = 0; i < oneshot_bank_count; i++) { if (strcmp(oneshot_bank[i].name, lc) == 0) return &oneshot_bank[i]; } return NULL;}
uint64_t audio_oneshot_play(ACAudio *audio, const char *name, double volume, double pan, double pitch_factor) { (void)audio; const OneShotSample *s = find_oneshot(name); if (!s) { ac_log("[oneshot] play '%s' — sample not in bank\n", name ? name : "(null)"); return 0; } if (pitch_factor <= 0.0) pitch_factor = 1.0; if (volume < 0.0) volume = 0.0; if (pan < -1.0) pan = -1.0; if (pan > 1.0) pan = 1.0;
pthread_mutex_lock(&oneshot_lock); // Find a free slot, or steal the oldest (lowest id) active voice. int slot = -1; uint64_t oldest_id = (uint64_t)-1; int oldest_slot = 0; for (int i = 0; i < ONESHOT_MAX_VOICES; i++) { if (!oneshot_voices[i].active) { slot = i; break; } if (oneshot_voices[i].id < oldest_id) { oldest_id = oneshot_voices[i].id; oldest_slot = i; } } if (slot < 0) slot = oldest_slot;
OneShotVoice *v = &oneshot_voices[slot]; v->active = 1; v->sample = s; v->position = 0.0; v->speed = pitch_factor; v->volume = volume; v->pan = pan; v->fade = 1.0; // no attack ramp for one-shots v->fade_target = 1.0; v->id = oneshot_next_id++; uint64_t id = v->id; pthread_mutex_unlock(&oneshot_lock); return id;}
void audio_oneshot_kill(ACAudio *audio, uint64_t id, double fade) { (void)audio; if (id == 0) return; pthread_mutex_lock(&oneshot_lock); for (int i = 0; i < ONESHOT_MAX_VOICES; i++) { OneShotVoice *v = &oneshot_voices[i]; if (!v->active || v->id != id) continue; if (fade <= 0.001) { v->active = 0; } else { v->fade_target = 0.0; } break; } pthread_mutex_unlock(&oneshot_lock);}
// ── Drum-skin friction ──//// The DSP lives in scratch_voice.c, dependency-free like gm_synth.c and// fluoddity_voice.c, so it can be built and auditioned without ALSA (see// tools/scratch-audition.c). This is only the wiring.static void mix_scratch(ACAudio *audio, double rate, double *mix_l, double *mix_r) { if (!scratch_voice_active(&audio->scratch)) return; double l = 0.0, r = 0.0; scratch_voice_render(&audio->scratch, rate, &l, &r); *mix_l += l; *mix_r += r;}
void audio_scratch_set(ACAudio *audio, double level, double cutoff, double resonance, double roughness, double release, double pan, int synthetic) { if (!audio) return; ScratchParams p = { .target = level, .cutoff = cutoff, .resonance = resonance, .roughness = roughness, .release = release, .pan = pan, .synthetic = synthetic, }; pthread_mutex_lock(&audio->lock); scratch_voice_set(&audio->scratch, &p); pthread_mutex_unlock(&audio->lock);}
void audio_scratch_stop(ACAudio *audio) { if (!audio) return; pthread_mutex_lock(&audio->lock); scratch_voice_stop(&audio->scratch); pthread_mutex_unlock(&audio->lock);}
// Mix all active one-shot voices into the (mix_l, mix_r) bus. Called// from the audio thread alongside the SampleVoice mixer.static void mix_oneshot_voices(double rate, double *mix_l, double *mix_r) { // 5 ms fade ramp at output rate — matches mix_sample_voice fade speed. double fade_speed = 1.0 / (0.005 * rate); pthread_mutex_lock(&oneshot_lock); for (int i = 0; i < ONESHOT_MAX_VOICES; i++) { OneShotVoice *v = &oneshot_voices[i]; if (!v->active || !v->sample || !v->sample->data || v->sample->len < 2) continue;
// Fade envelope (release ramp for sustained kills). if (v->fade < v->fade_target) { v->fade += fade_speed; if (v->fade > v->fade_target) v->fade = v->fade_target; } else if (v->fade > v->fade_target) { v->fade -= fade_speed; if (v->fade <= 0.0) { v->fade = 0.0; v->active = 0; continue; } }
int slen = v->sample->len; const float *buf = v->sample->data; double pos = v->position; if (pos < 0.0) pos = 0.0; if (pos >= (double)(slen - 1)) { v->active = 0; continue; } int p0 = (int)pos; int p1 = p0 + 1; if (p1 >= slen) p1 = p0; double frac = pos - (double)p0; double s = (double)buf[p0] * (1.0 - frac) + (double)buf[p1] * frac;
double vol = v->volume * v->fade; // Equal-power-ish pan: SampleVoice uses a 0.6 cosine-approx; mirror // that here so zoo voices sit at consistent levels with the rest. double l_gain = v->pan <= 0 ? 1.0 : 1.0 - v->pan * 0.6; double r_gain = v->pan >= 0 ? 1.0 : 1.0 + v->pan * 0.6; *mix_l += s * vol * l_gain; *mix_r += s * vol * r_gain;
v->position += v->speed; if (v->position >= (double)(slen - 1)) { v->active = 0; } } pthread_mutex_unlock(&oneshot_lock);}
// ============================================================// Gun synthesis — two models per preset// ============================================================//// CLASSIC (default) — three-layer kick+snare-style synthesis://// noise ──► BPF (mid-Q, ~2-6kHz) ──► amp_env(crack) ──┐// │// sin/tri ──► pitch_sweep(start→end) ──► amp_env(boom)─┼─► sum ──► out// │// noise ──► LPF (low-Q, ~200-2000Hz) ──► env(attack+decay)─┘//// • crack: instantaneous transient, exp decay 5-30 ms// • boom: pitched sine/triangle with fast downward sweep// (~250→40 Hz over 30-100 ms), exp amp decay// • tail: noisy residual rumble, optional linear attack ramp,// exp decay 100-800 ms//// This is how kick+snare drum synthesis works, applied to gunshots.// Cheap, predictable, sounds like the gunshot SFX you remember from// classic sample libraries and arcade games.//// PHYSICAL — digital waveguide barrel resonance + body modes://// excitation ──► (+) ──► boreDelay ─┬──► muzzleHPF ──► out// ▲ │// │ breech_reflect │// │ ▼// └─── boreLP ◄──── (−1 open-end refl)//// excitation ──► 3× bodyModes ──► +out (parallel)//// Bore length sets the cavity resonance ("boom" frequency); body// modes give metallic character. Better for cavity-dominated sounds// (grenade, RPG launch) where the bore behavior actually matters.//// Common to both: secondary trigger (N-wave / 2nd click), sustain fire// (LMG retrigger), ricochet pitch sweep on release.//// Bore buffer is SHARED with the whistle (whistle_bore_buf) — only the// physical model uses it.
typedef struct { GunModel model; // --- Common (both models) --- double master_amp; // overall layer scaling (0.4–2.0) double secondary_delay_ms; // 0 = no 2nd shot; else delay before re-trigger double secondary_amp; // amplitude of 2nd shot relative to primary int sustain_fire; // 1 = retrigger while held (LMG) double retrig_period_ms; // ms between retrigs (60000/RPM) // --- Classic-only --- double click_amp; // sub-ms HF transient gain (0=off, ~0.6 typical) double click_decay_ms; // very fast (0.3-0.8 ms) — the "tk" snap double crack_amp; // 0..1 mix gain double crack_decay_ms; // exp decay time of crack envelope double crack_fc; // BPF center Hz (2000-8000 typical) double crack_q; // BPF Q (1.0-3.0 typical) double boom_amp; // 0..1 mix gain double boom_freq_start; // Hz at trigger double boom_freq_end; // Hz settled (≈40-80) double boom_pitch_decay_ms; // time const for pitch sweep (10-50) double boom_amp_decay_ms; // amp decay time (30-200) double tail_amp; // 0..1 mix gain double tail_attack_ms; // 0 = instant double tail_decay_ms; // 100-800 double tail_fc; // LPF cutoff Hz (200-2000) double tail_q; // LPF Q (0.5-1.5) // --- Physical-only --- double bore_length_s; // seconds (= 2L/c) double bore_loss; // bore LPF alpha double breech_reflect; // 0..1 double pressure; // excitation peak double env_rate; // excitation decay rate (1/sec) double noise_gain; // turbulent noise on excitation double body_freq[3]; // mode freqs Hz double body_q[3]; // mode Q double body_amp[3]; // mode mix amplitudes double radiation; // muzzle HPF coeff} GunPresetParams;
// Per-weapon parameters. Most presets use CLASSIC for clean impact// sounds. Cavity-dominated weapons (grenade, RPG) keep the PHYSICAL// bore model where its long resonance helps.static const GunPresetParams gun_presets[GUN_PRESET_COUNT] = { // --- GUN_PISTOL (9mm, L≈100mm) — sharp crack, tiny sub, quick tail { .model = GUN_MODEL_CLASSIC, .master_amp = 1.1, .click_amp = 0.65, .click_decay_ms = 0.5, .crack_amp = 0.95, .crack_decay_ms = 7.0, .crack_fc = 3800, .crack_q = 2.6, .boom_amp = 0.55, .boom_freq_start = 220, .boom_freq_end = 55, .boom_pitch_decay_ms = 14, .boom_amp_decay_ms = 55, .tail_amp = 0.35, .tail_attack_ms = 0, .tail_decay_ms = 110, .tail_fc = 900, .tail_q = 0.8, // Physical alt (warB): short barrel, bright body modes .bore_length_s = 0.000588, .bore_loss = 0.55, .breech_reflect = 0.92, .pressure = 1.2, .env_rate = 3000.0, .noise_gain = 0.6, .body_freq = {1500, 4000, 8500}, .body_q = {12, 10, 8}, .body_amp = {0.30, 0.20, 0.15}, .radiation = 0.985 }, // --- GUN_RIFLE (AR-15, L≈400mm) — bright crack + supersonic N-wave tap { .model = GUN_MODEL_CLASSIC, .master_amp = 1.2, .click_amp = 0.75, .click_decay_ms = 0.6, .crack_amp = 1.05, .crack_decay_ms = 8.0, .crack_fc = 4500, .crack_q = 3.0, .boom_amp = 0.70, .boom_freq_start = 280, .boom_freq_end = 50, .boom_pitch_decay_ms = 18, .boom_amp_decay_ms = 90, .tail_amp = 0.45, .tail_attack_ms = 0, .tail_decay_ms = 220, .tail_fc = 1100, .tail_q = 0.7, .secondary_delay_ms = 0.9, .secondary_amp = 0.55, // Physical alt: longer bore, deep mode ring + N-wave secondary .bore_length_s = 0.00235, .bore_loss = 0.50, .breech_reflect = 0.95, .pressure = 1.5, .env_rate = 2500.0, .noise_gain = 0.5, .body_freq = {800, 2400, 6000}, .body_q = {14, 12, 10}, .body_amp = {0.35, 0.25, 0.15}, .radiation = 0.988 }, // --- GUN_SHOTGUN (12ga, L≈660mm, wide bore) — big low boom, noisy tail { .model = GUN_MODEL_CLASSIC, .master_amp = 1.4, .click_amp = 0.55, .click_decay_ms = 0.8, .crack_amp = 0.65, .crack_decay_ms = 12, .crack_fc = 2200, .crack_q = 1.8, .boom_amp = 1.10, .boom_freq_start = 260, .boom_freq_end = 38, .boom_pitch_decay_ms = 22, .boom_amp_decay_ms = 130, .tail_amp = 0.85, .tail_attack_ms = 4, .tail_decay_ms = 380, .tail_fc = 700, .tail_q = 0.6, // Physical alt: wide bore, low body modes .bore_length_s = 0.00388, .bore_loss = 0.40, .breech_reflect = 0.88, .pressure = 1.8, .env_rate = 1800.0, .noise_gain = 0.9, .body_freq = {400, 1200, 3500}, .body_q = {10, 8, 7}, .body_amp = {0.40, 0.25, 0.15}, .radiation = 0.965 }, // --- GUN_SMG (MP5, L≈225mm) — bright fast crack, full-auto ~1000 RPM { .model = GUN_MODEL_CLASSIC, .master_amp = 0.95, .click_amp = 0.55, .click_decay_ms = 0.4, .crack_amp = 0.85, .crack_decay_ms = 5.0, .crack_fc = 4200, .crack_q = 2.5, .boom_amp = 0.40, .boom_freq_start = 200, .boom_freq_end = 60, .boom_pitch_decay_ms = 10, .boom_amp_decay_ms = 40, .tail_amp = 0.28, .tail_attack_ms = 0, .tail_decay_ms = 80, .tail_fc = 1200, .tail_q = 0.7, .sustain_fire = 1, .retrig_period_ms = 60, // 1000 RPM // Physical alt .bore_length_s = 0.00132, .bore_loss = 0.58, .breech_reflect = 0.92, .pressure = 1.0, .env_rate = 3500.0, .noise_gain = 0.5, .body_freq = {1200, 3500, 7500}, .body_q = {12, 10, 8}, .body_amp = {0.30, 0.20, 0.13}, .radiation = 0.978 }, // --- GUN_SUPPRESSED — tiny click, no boom, mid-range "pfft" { .model = GUN_MODEL_CLASSIC, .master_amp = 0.7, .click_amp = 0.08, .click_decay_ms = 0.4, .crack_amp = 0.30, .crack_decay_ms = 6.0, .crack_fc = 1600, .crack_q = 1.1, .boom_amp = 0.10, .boom_freq_start = 150, .boom_freq_end = 80, .boom_pitch_decay_ms = 8, .boom_amp_decay_ms = 30, .tail_amp = 0.85, .tail_attack_ms = 6, .tail_decay_ms = 140, .tail_fc = 1800, .tail_q = 0.6, // Physical alt: heavy bore loss = absorptive baffles, low radiation .bore_length_s = 0.00100, .bore_loss = 0.85, .breech_reflect = 0.80, .pressure = 0.5, .env_rate = 1500.0, .noise_gain = 1.0, .body_freq = {600, 1500, 3000}, .body_q = {6, 5, 4}, .body_amp = {0.15, 0.10, 0.05}, .radiation = 0.85 }, // --- GUN_LMG (M60, L≈560mm) — rifle-class retriggered ~600 RPM // Master amp tamed so the first shot doesn't stand out from the // sustained burst (sustain-fire weapons also start their envelopes // at the average jitter level — see gun_init_voice). { .model = GUN_MODEL_CLASSIC, .master_amp = 0.9, .click_amp = 0.55, .click_decay_ms = 0.5, .crack_amp = 0.85, .crack_decay_ms = 7.0, .crack_fc = 3500, .crack_q = 2.6, .boom_amp = 0.65, .boom_freq_start = 250, .boom_freq_end = 48, .boom_pitch_decay_ms = 16, .boom_amp_decay_ms = 75, .tail_amp = 0.40, .tail_attack_ms = 0, .tail_decay_ms = 160, .tail_fc = 950, .tail_q = 0.7, .sustain_fire = 1, .retrig_period_ms = 100, // 600 RPM // Physical alt .bore_length_s = 0.00329, .bore_loss = 0.48, .breech_reflect = 0.94, .pressure = 1.4, .env_rate = 2200.0, .noise_gain = 0.55, .body_freq = {600, 1800, 4500}, .body_q = {12, 10, 8}, .body_amp = {0.35, 0.25, 0.15}, .radiation = 0.982 }, // --- GUN_SNIPER (.50, L≈740mm) — huge crack + N-wave + long tail { .model = GUN_MODEL_CLASSIC, .master_amp = 1.5, .click_amp = 0.85, .click_decay_ms = 0.7, .crack_amp = 1.20, .crack_decay_ms = 11, .crack_fc = 5000, .crack_q = 3.2, .boom_amp = 1.20, .boom_freq_start = 320, .boom_freq_end = 36, .boom_pitch_decay_ms = 28, .boom_amp_decay_ms = 180, .tail_amp = 0.70, .tail_attack_ms = 3, .tail_decay_ms = 500, .tail_fc = 850, .tail_q = 0.8, .secondary_delay_ms = 1.4, .secondary_amp = 0.70, // Physical alt: high pressure, long ring .bore_length_s = 0.00435, .bore_loss = 0.35, .breech_reflect = 0.97, .pressure = 2.0, .env_rate = 1500.0, .noise_gain = 0.7, .body_freq = {350, 950, 2800}, .body_q = {14, 12, 10}, .body_amp = {0.50, 0.30, 0.15}, .radiation = 0.992 }, // --- GUN_GRENADE — large cavity, slow release. Default = PHYSICAL // (the long bore resonance makes the cavity feel right). Classic // alt is a very low boom + heavy noisy tail for the kaboom. { .model = GUN_MODEL_PHYSICAL, .bore_length_s = 0.01000, .bore_loss = 0.25, .breech_reflect = 0.60, .pressure = 1.6, .env_rate = 400.0, .noise_gain = 1.5, .body_freq = {80, 250, 1200}, .body_q = {6, 5, 4}, .body_amp = {0.60, 0.35, 0.15}, .radiation = 0.70, // Classic alt (warA): tiny click, huge boom, very long tail .master_amp = 1.6, .click_amp = 0.40, .click_decay_ms = 1.0, .crack_amp = 0.45, .crack_decay_ms = 25, .crack_fc = 800, .crack_q = 0.7, .boom_amp = 1.50, .boom_freq_start = 150, .boom_freq_end = 28, .boom_pitch_decay_ms = 60, .boom_amp_decay_ms = 350, .tail_amp = 1.50, .tail_attack_ms = 12, .tail_decay_ms = 800, .tail_fc = 400, .tail_q = 0.4 }, // --- GUN_RPG — long motor burn + delayed boom. Default = PHYSICAL // (the slow bore loop nicely models the rocket exhaust whoosh). { .model = GUN_MODEL_PHYSICAL, .bore_length_s = 0.00300, .bore_loss = 0.30, .breech_reflect = 0.50, .pressure = 1.2, .env_rate = 150.0, .noise_gain = 2.5, .body_freq = {200, 600, 2000}, .body_q = {4, 3, 3}, .body_amp = {0.40, 0.30, 0.20}, .radiation = 0.60, .secondary_delay_ms = 250, .secondary_amp = 1.5, // Classic alt: launch click, sustained noise (motor) + delayed boom .master_amp = 1.3, .click_amp = 0.30, .click_decay_ms = 0.8, .crack_amp = 0.40, .crack_decay_ms = 20, .crack_fc = 1500, .crack_q = 0.8, .boom_amp = 0.30, .boom_freq_start = 120, .boom_freq_end = 60, .boom_pitch_decay_ms = 30, .boom_amp_decay_ms = 100, .tail_amp = 2.00, .tail_attack_ms = 80, .tail_decay_ms = 600, .tail_fc = 600, .tail_q = 0.5 }, // --- GUN_RELOAD — magazine clack: bright HF click + bandpass burst { .model = GUN_MODEL_CLASSIC, .master_amp = 0.75, .click_amp = 0.85, .click_decay_ms = 0.4, .crack_amp = 0.90, .crack_decay_ms = 4.0, .crack_fc = 4500, .crack_q = 3.0, .boom_amp = 0.0, .boom_freq_start = 0, .boom_freq_end = 0, .boom_pitch_decay_ms = 1, .boom_amp_decay_ms = 1, .tail_amp = 0.20, .tail_attack_ms = 0, .tail_decay_ms = 30, .tail_fc = 2500, .tail_q = 0.6, .secondary_delay_ms = 80, .secondary_amp = 0.65, // Physical alt: tiny bore = sharp metallic transient + insert click .bore_length_s = 0.00010, .bore_loss = 0.70, .breech_reflect = 0.90, .pressure = 0.6, .env_rate = 4000.0, .noise_gain = 0.3, .body_freq = {2200, 4500, 8000}, .body_q = {10, 8, 6}, .body_amp = {0.40, 0.30, 0.15}, .radiation = 0.92 }, // --- GUN_COCK — bolt-action click-clack (two crisp clicks) { .model = GUN_MODEL_CLASSIC, .master_amp = 0.8, .click_amp = 0.90, .click_decay_ms = 0.4, .crack_amp = 1.00, .crack_decay_ms = 5.0, .crack_fc = 3800, .crack_q = 3.2, .boom_amp = 0.0, .boom_freq_start = 0, .boom_freq_end = 0, .boom_pitch_decay_ms = 1, .boom_amp_decay_ms = 1, .tail_amp = 0.15, .tail_attack_ms = 0, .tail_decay_ms = 25, .tail_fc = 2000, .tail_q = 0.6, .secondary_delay_ms = 55, .secondary_amp = 0.80, // Physical alt .bore_length_s = 0.00015, .bore_loss = 0.65, .breech_reflect = 0.88, .pressure = 0.7, .env_rate = 3500.0, .noise_gain = 0.35, .body_freq = {1800, 4200, 7500}, .body_q = {10, 8, 7}, .body_amp = {0.45, 0.25, 0.15}, .radiation = 0.92 }, // --- GUN_RICOCHET — pitched ping with downward pitch on release { .model = GUN_MODEL_CLASSIC, .master_amp = 0.85, .click_amp = 0.40, .click_decay_ms = 0.5, .crack_amp = 0.35, .crack_decay_ms = 7.0, .crack_fc = 5500, .crack_q = 3.0, .boom_amp = 0.95, .boom_freq_start = 1800,.boom_freq_end = 1500, .boom_pitch_decay_ms = 60, .boom_amp_decay_ms = 350, .tail_amp = 0.20, .tail_attack_ms = 0, .tail_decay_ms = 200, .tail_fc = 3000, .tail_q = 1.0, // Physical alt: high-Q metallic ring (ricochet really IS that) .bore_length_s = 0.00040, .bore_loss = 0.15, .breech_reflect = 0.90, .pressure = 0.8, .env_rate = 600.0, .noise_gain = 0.3, .body_freq = {3000, 5500, 9000}, .body_q = {30, 25, 20}, .body_amp = {0.40, 0.25, 0.15}, .radiation = 0.975 },};
// ----- helper: precompute 2-pole resonant filter coefficients -----// y = b0*x + a1*y[n-1] - a2*y[n-2]// a1 = 2·r·cos(w), a2 = r², r = exp(-π·f / (Q·sr)), w = 2π·f/sr// Output peak gain ≈ 1/(1-a1+a2) at DC and varies with Q. The b0 input// gain is scaled so the resonant peak is approximately unity, making// per-layer mix amps map to roughly equal loudness regardless of Q.static inline void compute_resonator(double f, double q, double sr, double *a1, double *a2, double *b0) { if (q < 0.4) q = 0.4; if (f < 20.0) f = 20.0; if (f > sr * 0.45) f = sr * 0.45; double r = exp(-M_PI * f / (q * sr)); double w = 2.0 * M_PI * f / sr; *a1 = 2.0 * r * cos(w); *a2 = r * r; // Peak gain of a 2-pole resonator ≈ 1/(1 - r). Pre-attenuate input // by that factor so the resonant peak stays near unity amplitude. *b0 = (1.0 - r);}
// Initialize a voice's gun state from a preset. Called from audio_synth_gun.// `force_model` overrides the preset's default model: -1 = preset default,// 0 = CLASSIC, 1 = PHYSICAL. The preset table holds parameters for both// models so the override always finds a populated config.static void gun_init_voice(ACVoice *v, GunPreset preset, double sr, int force_model) { if (preset < 0 || preset >= GUN_PRESET_COUNT) preset = GUN_PISTOL; const GunPresetParams *p = &gun_presets[preset];
v->gun_preset = (int)preset; v->gun_model = (force_model == 0 || force_model == 1) ? force_model : (int)p->model; v->gun_pressure = p->master_amp > 0.0 ? p->master_amp : 1.0; // Sustain-fire weapons (SMG/LMG) start at the same gentler level // their internal retrigger uses (avg jitter ≈ 0.95) so the first // shot blends with the rapid-fire stream instead of standing out. v->gun_pressure_env = p->sustain_fire ? 0.92 : 1.0; v->gun_secondary_trig = p->secondary_delay_ms > 0 ? p->secondary_delay_ms * 0.001 * sr : 0.0; v->gun_secondary_amp = p->secondary_amp; v->gun_sustain_fire = p->sustain_fire; v->gun_retrig_timer = 0.0; v->gun_retrig_period = p->retrig_period_ms * 0.001;
// Pitch sweep: nominal 1.0 at trigger. Ricochet sets target<1.0 on // release so boom freq drops (doppler-style). v->gun_pitch_mult = 1.0; v->gun_pitch_target = 1.0; v->gun_pitch_slew = 1.0 / (0.3 * sr);
if (v->gun_model == GUN_MODEL_CLASSIC) { // Crack: exp decay multiplier from time-constant tau (in ms). double tau_crack = (p->crack_decay_ms > 0.1 ? p->crack_decay_ms : 0.1) * 0.001; v->gun_env_decay_mult = exp(-1.0 / (tau_crack * sr));
// Boom: pitch sweep from start→end via geometric approach. // After tau seconds, distance to target is ~e^{-1} of original. v->gun_boom_freq_start = p->boom_freq_start; v->gun_boom_freq_end = p->boom_freq_end; v->gun_boom_freq = p->boom_freq_start; v->gun_boom_phase = 0.0; double tau_pitch = (p->boom_pitch_decay_ms > 0.1 ? p->boom_pitch_decay_ms : 0.1) * 0.001; v->gun_boom_pitch_mult = exp(-1.0 / (tau_pitch * sr)); double tau_boom = (p->boom_amp_decay_ms > 0.1 ? p->boom_amp_decay_ms : 0.1) * 0.001; v->gun_boom_decay_mult = exp(-1.0 / (tau_boom * sr)); v->gun_boom_env = (p->boom_amp > 0.0) ? (p->sustain_fire ? 0.92 : 1.0) : 0.0;
// Tail: linear attack ramp + exp decay. v->gun_tail_env = (p->tail_attack_ms > 0.0) ? 0.0 : 1.0; if (p->tail_attack_ms > 0.0) { v->gun_tail_attack_inc = 1.0 / (p->tail_attack_ms * 0.001 * sr); } else { v->gun_tail_attack_inc = 0.0; } double tau_tail = (p->tail_decay_ms > 0.1 ? p->tail_decay_ms : 0.1) * 0.001; v->gun_tail_decay_mult = exp(-1.0 / (tau_tail * sr));
// Filter coeffs: body slot [0] = crack BPF, [1] = tail LPF. compute_resonator(p->crack_fc, p->crack_q, sr, &v->gun_body_a1[0], &v->gun_body_a2[0], &v->gun_crack_b0); compute_resonator(p->tail_fc, p->tail_q, sr, &v->gun_body_a1[1], &v->gun_body_a2[1], &v->gun_tail_b0); v->gun_tail_b1 = 0.0; v->gun_tail_b2 = 0.0; v->gun_body_y1[0] = v->gun_body_y2[0] = 0.0; v->gun_body_y1[1] = v->gun_body_y2[1] = 0.0; v->gun_body_y1[2] = v->gun_body_y2[2] = 0.0; // Layer mix gains. v->gun_body_amp[0] = p->crack_amp; v->gun_body_amp[1] = p->boom_amp; v->gun_body_amp[2] = p->tail_amp; // Click layer (sub-ms HF transient — adds the "tk" snap). v->gun_click_amp = p->click_amp; v->gun_click_env = (p->click_amp > 0.0) ? (p->sustain_fire ? 0.92 : 1.0) : 0.0; v->gun_click_prev = 0.0; double tau_click = (p->click_decay_ms > 0.05 ? p->click_decay_ms : 0.05) * 0.001; v->gun_click_decay_mult = exp(-1.0 / (tau_click * sr)); // Physical-only fields zeroed for safety. v->gun_bore_delay = 0.0; v->gun_bore_loss = 0.0; v->gun_bore_lp = 0.0; v->gun_breech_reflect = 0.0; v->gun_noise_gain = 0.0; v->gun_radiation_a = 0.0; v->gun_rad_prev = 0.0; memset(v->whistle_bore_buf, 0, sizeof(v->whistle_bore_buf)); v->whistle_bore_w = 0; } else { // PHYSICAL model — DWG bore + body modes. v->gun_bore_delay = p->bore_length_s * sr; if (v->gun_bore_delay < 4.0) v->gun_bore_delay = 4.0; if (v->gun_bore_delay > 2040.0) v->gun_bore_delay = 2040.0; v->gun_bore_loss = p->bore_loss; v->gun_bore_lp = 0.0; v->gun_breech_reflect = p->breech_reflect; v->gun_pressure = p->pressure; // physical uses its own pressure scale v->gun_env_decay_mult = exp(-p->env_rate / sr); v->gun_noise_gain = p->noise_gain; v->gun_radiation_a = p->radiation; v->gun_rad_prev = 0.0; for (int i = 0; i < 3; i++) { double a1, a2, b0_unused; compute_resonator(p->body_freq[i], p->body_q[i], sr, &a1, &a2, &b0_unused); v->gun_body_a1[i] = a1; v->gun_body_a2[i] = a2; v->gun_body_amp[i] = p->body_amp[i]; v->gun_body_y1[i] = 0.0; v->gun_body_y2[i] = 0.0; } memset(v->whistle_bore_buf, 0, sizeof(v->whistle_bore_buf)); v->whistle_bore_w = 0; // Friedlander pulse params. t+ derived from env_rate so existing // preset tunings still feel right: shorter env_rate → wider pulse // (grenade ~7ms, pistol ~1ms). Friedlander A = 1.5 is a good // default for the positive-phase decay shape. v->gun_phys_t = 0.0; v->gun_phys_t_plus = (3.0 / (p->env_rate > 100 ? p->env_rate : 100.0)) * sr; if (v->gun_phys_t_plus < 32.0) v->gun_phys_t_plus = 32.0; // ≥ ~0.17ms if (v->gun_phys_t_plus > 4096.0) v->gun_phys_t_plus = 4096.0; // ≤ ~21ms v->gun_phys_friedlander_a = 1.5; v->gun_phys_neg_amp = 0.18; // Ground reflection — fixed ~3.5ms tap with 18% gain. Caps at // 1023 samples = ~5.3ms at 192kHz. Tunable per-preset later. v->gun_phys_echo_delay = 0.0035 * sr; if (v->gun_phys_echo_delay > 1023.0) v->gun_phys_echo_delay = 1023.0; v->gun_phys_echo_amp = 0.22; memset(v->gun_phys_echo_buf, 0, sizeof(v->gun_phys_echo_buf)); v->gun_phys_echo_w = 0; // Classic-only fields zeroed. v->gun_boom_phase = 0.0; v->gun_boom_freq = 0.0; v->gun_boom_freq_start = 0.0; v->gun_boom_freq_end = 0.0; v->gun_boom_pitch_mult = 1.0; v->gun_boom_env = 0.0; v->gun_boom_decay_mult = 1.0; v->gun_tail_env = 0.0; v->gun_tail_attack_inc = 0.0; v->gun_tail_decay_mult = 1.0; v->gun_crack_b0 = 0.0; v->gun_tail_b0 = v->gun_tail_b1 = v->gun_tail_b2 = 0.0; v->gun_click_amp = 0.0; v->gun_click_env = 0.0; v->gun_click_decay_mult = 1.0; v->gun_click_prev = 0.0; v->gun_phys_t = 0.0; v->gun_phys_t_plus = 0.0; v->gun_phys_friedlander_a = 0.0; v->gun_phys_neg_amp = 0.0; v->gun_phys_echo_delay = 0.0; v->gun_phys_echo_amp = 0.0; v->gun_phys_echo_w = 0; }}
// Called when a gun voice enters VOICE_KILLING — sets up release-time// behaviors (ricochet pitch drop applies to both models via gun_pitch_mult).static inline void gun_on_release(ACVoice *v) { if (v->type != WAVE_GUN) return; if (v->gun_preset == GUN_RICOCHET) { // Drop pitch on release — for classic this scales boom freq down; // for physical it stretches the bore delay (doppler). v->gun_pitch_target = (v->gun_model == GUN_MODEL_CLASSIC) ? 0.35 : 2.8; }}
// Three-layer kick/snare-style gunshot synthesis. Output is summed// crack (BPF noise) + boom (pitched osc with downward sweep) + tail// (LPF noise with attack-decay), then scaled by master amp and the// piece-supplied envelope.static inline double generate_gun_classic_sample(ACVoice *v, double sr) { // --- Secondary trigger (rifle N-wave / 2nd click of cock/reload) --- if (v->gun_secondary_trig > 0.0) { v->gun_secondary_trig -= 1.0; if (v->gun_secondary_trig <= 0.0) { v->gun_pressure_env = v->gun_secondary_amp; // refire crack v->gun_boom_env = v->gun_secondary_amp * 0.6; // gentler boom v->gun_click_env = v->gun_secondary_amp; // refire click too v->gun_secondary_trig = 0.0; } }
// --- LMG sustain-fire retrigger --- if (v->gun_sustain_fire && v->state == VOICE_ACTIVE && isinf(v->duration) && v->gun_retrig_period > 0.0) { v->gun_retrig_timer += 1.0 / sr; if (v->gun_retrig_timer >= v->gun_retrig_period) { v->gun_retrig_timer -= v->gun_retrig_period; double j = (double)xorshift32(&v->noise_seed) / (double)UINT32_MAX; double jitter = 0.82 + j * 0.32; // ±18% v->gun_pressure_env = jitter; v->gun_boom_env = jitter; v->gun_click_env = jitter; v->gun_boom_freq = v->gun_boom_freq_start; // restart pitch sweep // Tail keeps decaying (no re-attack) so rapid-fire feels continuous. } }
// --- Pitch sweep (ricochet release doppler) --- if (v->gun_pitch_mult != v->gun_pitch_target) { v->gun_pitch_mult += (v->gun_pitch_target - v->gun_pitch_mult) * 0.00012; }
// === Layer 0: CLICK — sub-millisecond HF transient === // 1-zero HPF on white noise (y = x - x[n-1]) emphasizes the highest // frequencies. Combined with a ~0.5ms tau exp envelope it reads as // the sharp "tk" attack you expect at the front of a gunshot — // without it, the BPF crack on its own sounds like a shaped hiss. double click = 0.0; if (v->gun_click_env > 0.00002 && v->gun_click_amp > 0.0) { double white = ((double)xorshift32(&v->noise_seed) / (double)UINT32_MAX) * 2.0 - 1.0; double hp = white - v->gun_click_prev; v->gun_click_prev = white; click = hp * v->gun_click_env * v->gun_click_amp; v->gun_click_env *= v->gun_click_decay_mult; }
// === Layer 1: CRACK — bandpass-filtered noise burst === double crack = 0.0; if (v->gun_pressure_env > 0.00002 && v->gun_body_amp[0] > 0.0) { double white = ((double)xorshift32(&v->noise_seed) / (double)UINT32_MAX) * 2.0 - 1.0; // 2-pole resonator (bandpass-like) on white noise. double y = v->gun_crack_b0 * white + v->gun_body_a1[0] * v->gun_body_y1[0] - v->gun_body_a2[0] * v->gun_body_y2[0]; v->gun_body_y2[0] = v->gun_body_y1[0]; v->gun_body_y1[0] = y; crack = y * v->gun_pressure_env * v->gun_body_amp[0]; v->gun_pressure_env *= v->gun_env_decay_mult; }
// === Layer 2: BOOM — pitched triangle with exponential pitch drop === double boom = 0.0; if (v->gun_boom_env > 0.00002 && v->gun_body_amp[1] > 0.0) { // Geometric approach toward end freq. For typical 14ms tau at // 192kHz, this glides 250→55 Hz audibly within ~50ms. v->gun_boom_freq = v->gun_boom_freq_end + (v->gun_boom_freq - v->gun_boom_freq_end) * v->gun_boom_pitch_mult; double f = v->gun_boom_freq * v->gun_pitch_mult; if (f < 1.0) f = 1.0; v->gun_boom_phase += f / sr; if (v->gun_boom_phase >= 1.0) v->gun_boom_phase -= 1.0; if (v->gun_boom_phase < 0.0) v->gun_boom_phase += 1.0; // Triangle wave — fatter low-end punch than sine, less harsh than square. double tp = v->gun_boom_phase; double s = (tp < 0.5) ? (4.0 * tp - 1.0) : (3.0 - 4.0 * tp); boom = s * v->gun_boom_env * v->gun_body_amp[1]; v->gun_boom_env *= v->gun_boom_decay_mult; }
// === Layer 3: TAIL — lowpass-filtered noise rumble === double tail = 0.0; if (v->gun_body_amp[2] > 0.0) { // Envelope: linear ramp during attack phase, then exp decay. if (v->gun_tail_attack_inc > 0.0) { v->gun_tail_env += v->gun_tail_attack_inc; if (v->gun_tail_env >= 1.0) { v->gun_tail_env = 1.0; v->gun_tail_attack_inc = 0.0; // attack done; switch to decay } } else if (v->gun_tail_env > 0.00001) { v->gun_tail_env *= v->gun_tail_decay_mult; } if (v->gun_tail_env > 0.00001) { double white = ((double)xorshift32(&v->noise_seed) / (double)UINT32_MAX) * 2.0 - 1.0; // 2-pole resonator at low freq, low Q ≈ 1-pole-ish lowpass behavior. double y = v->gun_tail_b0 * white + v->gun_body_a1[1] * v->gun_body_y1[1] - v->gun_body_a2[1] * v->gun_body_y2[1]; v->gun_body_y2[1] = v->gun_body_y1[1]; v->gun_body_y1[1] = y; tail = y * v->gun_tail_env * v->gun_body_amp[2]; } }
// Click also retriggers on secondary/sustain events because gun_click_env // gets reset in those branches via gun_pressure_env (no — actually it // doesn't; we only reset crack/boom there). Fold a small click retrigger // into the secondary path so reload+cock 2nd hits feel just as crisp. double out = (click + crack + boom + tail) * v->gun_pressure; return out * compute_envelope(v);}
// Physical-model gunshot — Friedlander blast wave excitation feeding a// DWG bore + parallel body modes + muzzle radiation HPF + ground-echo// tap. Better for cavity-dominated weapons (grenade, RPG launch tube)// where the bore length is meaningful.//// The Friedlander waveform models the actual pressure-vs-time curve of// a free-air blast wave:// P(t) = P_peak · (1 − t/t+) · exp(−A·t/t+) for 0 ≤ t ≤ t+// P(t) ≈ −P_peak · neg_amp · (1−tn) · exp(−2·tn) for t > t+// (where tn = (t−t+) / (4·t+))// (Friedlander 1946; widely used in blast-wave acoustics — see Mengual// et al. 2017 "Procedural Synthesis of Gunshot Sounds…")//// The ground-echo tap (a single delayed copy of the radiated signal,// ~3-5 ms behind, attenuated) gives the spatial sense of an outdoor// shot — without it, the whole thing sounds anechoic and wrong.static inline double generate_gun_physical_sample(ACVoice *v, double sr) { // === Excitation: Friedlander envelope shaping a noise burst === // Pure Friedlander pulses are too smooth between samples — the muzzle // radiation HPF (1-zero differentiator at α≈0.985) annihilates anything // that doesn't change between adjacent samples, killing the radiated // path entirely. So we use Friedlander as the AMPLITUDE ENVELOPE of a // noise burst (rather than the signal itself). The smooth shape gives // us the right onset/decay character; the noise content gives the HPF // and bore loop high-frequency material to actually radiate and ring. double t = v->gun_phys_t; double t_plus = v->gun_phys_t_plus; double A = v->gun_phys_friedlander_a; double pulse = 0.0; if (t < t_plus) { // Positive phase — sharp peak then exp decay. double f = t / t_plus; pulse = (1.0 - f) * exp(-A * f); } else if (t < t_plus * 5.0) { // Negative phase — sub-atmospheric dip after the wave passes. double tn = (t - t_plus) / (t_plus * 4.0); pulse = -v->gun_phys_neg_amp * (1.0 - tn) * exp(-2.0 * tn); } uint32_t n = xorshift32(&v->noise_seed); double white = ((double)n / (double)UINT32_MAX) * 2.0 - 1.0; // Smooth deterministic component + noise rider. noise_gain mixes the // turbulent content. The smooth term keeps low-freq energy for the // bore loop; the noise term feeds the radiation HPF + body modes. double excite = v->gun_pressure * pulse * (1.0 + v->gun_noise_gain * white); v->gun_phys_t += 1.0;
// Secondary trigger — rifle N-wave or RPG delayed explosion. Restarts // the Friedlander pulse from t=0 with a scaled peak. if (v->gun_secondary_trig > 0.0) { v->gun_secondary_trig -= 1.0; if (v->gun_secondary_trig <= 0.0) { v->gun_phys_t = 0.0; v->gun_pressure *= v->gun_secondary_amp; v->gun_secondary_trig = 0.0; } }
// Sustain fire — restart pulse at jitter scale. if (v->gun_sustain_fire && v->state == VOICE_ACTIVE && isinf(v->duration) && v->gun_retrig_period > 0.0) { v->gun_retrig_timer += 1.0 / sr; if (v->gun_retrig_timer >= v->gun_retrig_period) { v->gun_retrig_timer -= v->gun_retrig_period; v->gun_phys_t = 0.0; double j = (double)xorshift32(&v->noise_seed) / (double)UINT32_MAX; // Tiny per-shot pressure variance around 1.0 (no permanent drift). v->gun_pressure *= 0.92 + j * 0.16; } }
// Pitch sweep approach (ricochet — currently classic-only, kept for parity). if (v->gun_pitch_mult != v->gun_pitch_target) { v->gun_pitch_mult += (v->gun_pitch_target - v->gun_pitch_mult) * 0.00012; } double bore_delay = v->gun_bore_delay * v->gun_pitch_mult; if (bore_delay < 4.0) bore_delay = 4.0; if (bore_delay > 2040.0) bore_delay = 2040.0;
// === Bore: closed breech (+refl) / open muzzle (−refl + LPF damping) === const int BORE_N = 2048; double bore_out = whistle_frac_read(v->whistle_bore_buf, BORE_N, v->whistle_bore_w, bore_delay); v->gun_bore_lp = v->gun_bore_loss * (-bore_out) + (1.0 - v->gun_bore_loss) * v->gun_bore_lp; double refl = v->gun_bore_lp; double into_bore = excite + refl * v->gun_breech_reflect; v->whistle_bore_buf[v->whistle_bore_w] = (float)into_bore; v->whistle_bore_w = (v->whistle_bore_w + 1) % BORE_N;
// === Muzzle radiation: 1-zero HPF (open end emphasizes highs) === double radiated = into_bore - v->gun_radiation_a * v->gun_rad_prev; v->gun_rad_prev = into_bore;
// === Body modes: parallel pole-pair resonators on the excitation === double body = 0.0; for (int i = 0; i < 3; i++) { double y = excite + v->gun_body_a1[i] * v->gun_body_y1[i] - v->gun_body_a2[i] * v->gun_body_y2[i]; v->gun_body_y2[i] = v->gun_body_y1[i]; v->gun_body_y1[i] = y; body += y * v->gun_body_amp[i]; }
double dry = radiated * 0.55 + body * 0.45;
// === Ground reflection echo — short delayed copy. Even at low // amplitude this turns the dry shot into a "fired outdoors" shot. double echo_out = 0.0; if (v->gun_phys_echo_amp > 0.0 && v->gun_phys_echo_delay > 1.0) { const int ECHO_N = 1024; int read_pos = v->gun_phys_echo_w - (int)v->gun_phys_echo_delay; while (read_pos < 0) read_pos += ECHO_N; echo_out = (double)v->gun_phys_echo_buf[read_pos % ECHO_N] * v->gun_phys_echo_amp; v->gun_phys_echo_buf[v->gun_phys_echo_w] = (float)dry; v->gun_phys_echo_w = (v->gun_phys_echo_w + 1) % ECHO_N; }
return (dry + echo_out) * compute_envelope(v);}
static inline double generate_gun_sample(ACVoice *v, double sr) { if (v->gun_model == GUN_MODEL_PHYSICAL) { return generate_gun_physical_sample(v, sr); } return generate_gun_classic_sample(v, sr);}
static inline double compute_fade(ACVoice *v) { if (v->state != VOICE_KILLING) return 1.0; if (v->fade_duration <= 0.0) return 0.0; double progress = v->fade_elapsed / v->fade_duration; if (progress >= 1.0) return 0.0; return 1.0 - progress;}
static inline double generate_sample(ACVoice *v, double sample_rate) { double s; switch (v->type) { case WAVE_SINE: s = sin(2.0 * M_PI * v->phase); break; case WAVE_SQUARE: s = v->phase < 0.5 ? 1.0 : -1.0; break; case WAVE_TRIANGLE: { // Offset phase by 0.25 to start at zero crossing (matches synth.mjs) double tp = v->phase + 0.25; if (tp >= 1.0) tp -= 1.0; s = 4.0 * fabs(tp - 0.5) - 1.0; break; } case WAVE_SAWTOOTH: s = 2.0 * v->phase - 1.0; break; case WAVE_NOISE: { // Filtered white noise using biquad LPF double white = ((double)xorshift32(&v->noise_seed) / (double)UINT32_MAX) * 2.0 - 1.0; double y = v->noise_b0 * white + v->noise_b1 * v->noise_x1 + v->noise_b2 * v->noise_x2 - v->noise_a1 * v->noise_y1 - v->noise_a2 * v->noise_y2; v->noise_x2 = v->noise_x1; v->noise_x1 = white; v->noise_y2 = v->noise_y1; v->noise_y1 = y; s = y; break; } case WAVE_WHISTLE: s = generate_whistle_sample(v, sample_rate); break; case WAVE_GUN: s = generate_gun_sample(v, sample_rate); break; case WAVE_HARP: s = generate_harp_sample(v, sample_rate); break; case WAVE_PIANO: s = generate_piano_sample(v, sample_rate); break; case WAVE_GMPIANO: case WAVE_EPIANO: case WAVE_PLUCK: case WAVE_MODAL: case WAVE_SYNTHBASS: // All GM voices render through the standalone gm_synth module. The // engine supplies the amplitude envelope + current (smoothed) frequency; // gm_synth owns the rest of the DSP state (ACVoice.gm) and dispatches on // its own stored engine type. s = gm_voice_render(&v->gm, sample_rate, compute_envelope(v), v->frequency); break; default: s = 0.0; }
// Smooth frequency toward target (uses precomputed alpha from caller) if (v->target_frequency > 0 && v->frequency != v->target_frequency) { v->frequency += (v->target_frequency - v->frequency) * 0.0003; // ~5ms at 192kHz }
// Advance phase for basic oscillators; whistle/gun/harp/piano and the GM // synthesis voices (gmpiano/epiano/pluck/modal/synthbass) manage their own // phase state internally. if (v->type != WAVE_WHISTLE && v->type != WAVE_GUN && v->type != WAVE_HARP && v->type != WAVE_PIANO && v->type != WAVE_GMPIANO && v->type != WAVE_EPIANO && v->type != WAVE_PLUCK && v->type != WAVE_MODAL && v->type != WAVE_SYNTHBASS) { v->phase += v->frequency / sample_rate; if (v->phase >= 1.0) v->phase -= 1.0; }
return s;}
// Setup biquad LPF coefficients for noise voicestatic void setup_noise_filter(ACVoice *v, double sample_rate) { double cutoff = v->frequency; if (cutoff < 20.0) cutoff = 20.0; if (cutoff > sample_rate / 2.0) cutoff = sample_rate / 2.0;
double Q = 1.0; double w0 = 2.0 * M_PI * cutoff / sample_rate; double alpha = sin(w0) / (2.0 * Q);
double b0 = (1.0 - cos(w0)) / 2.0; double b1 = 1.0 - cos(w0); double b2 = (1.0 - cos(w0)) / 2.0; double a0 = 1.0 + alpha; double a1 = -2.0 * cos(w0); double a2 = 1.0 - alpha;
v->noise_b0 = b0 / a0; v->noise_b1 = b1 / a0; v->noise_b2 = b2 / a0; v->noise_a1 = a1 / a0; v->noise_a2 = a2 / a0; v->noise_x1 = v->noise_x2 = v->noise_y1 = v->noise_y2 = 0.0;}
// ============================================================// Audio thread// ============================================================
#define ROOM_DELAY_SAMPLES (int)(0.12 * AUDIO_SAMPLE_RATE) // 120ms#define ROOM_SIZE (ROOM_DELAY_SAMPLES * 3)#define ROOM_FEEDBACK 0.3#define ROOM_MIX 0.35
// Soft clamp (tanh-style) to prevent harsh digital clipping// Smooth curve: starts compressing gently above 0.6, hard-limits at ~0.95static inline double soft_clip(double x) { /* tanh-based soft limiter — much smoother than the previous * piecewise clipper which had a kinked transfer curve above * the knee, producing "fuzzy" / tinny distortion at high gain. * tanh(x * 0.9) stays linear to ~0.6, eases through 0.85, and * asymptotes at ±1.0. Adds only small even-order harmonics * which sound "warm" instead of harsh. */ return tanh(x * 0.9) / tanh(0.9);}
// Compressor state (per-channel peak follower)static double comp_env = 0.0; // envelope follower levelstatic unsigned long xrun_count = 0;static unsigned long short_write_count = 0;
static void mix_sample_voice(SampleVoice *sv, const float *buf, int slen, int smax, double rate, double *mix_l, double *mix_r) { if (!sv || !sv->active || !buf || slen <= 0 || smax <= 0) { if (sv) sv->active = 0; return; }
if (slen > smax) slen = smax;
// Fade envelope (5ms attack/release at output rate) double fade_speed = 1.0 / (0.005 * rate); if (sv->fade < sv->fade_target) { sv->fade += fade_speed; if (sv->fade > sv->fade_target) sv->fade = sv->fade_target; } else if (sv->fade > sv->fade_target) { sv->fade -= fade_speed; if (sv->fade <= 0.0) { sv->fade = 0.0; sv->active = 0; return; } }
// Pan controls both amplitude and a small Haas-style stereo offset. double delay_samps = sv->pan * 0.0004 * rate; double pos_l = sv->position - (delay_samps > 0 ? delay_samps : 0); double pos_r = sv->position + (delay_samps > 0 ? 0 : delay_samps); if (pos_l < 0) pos_l = 0; if (pos_r < 0) pos_r = 0;
int p0l = (int)pos_l; if (sv->loop) { p0l = ((p0l % slen) + slen) % slen; } else if (p0l >= slen) { sv->active = 0; return; } int p1l = p0l + 1; if (p1l >= slen) p1l = sv->loop ? 0 : p0l; if (p0l >= smax || p1l >= smax) { sv->active = 0; return; } double fl = pos_l - p0l; double samp_l = buf[p0l] * (1.0 - fl) + buf[p1l] * fl;
int p0r = (int)pos_r; if (sv->loop) { p0r = ((p0r % slen) + slen) % slen; } else if (p0r >= slen) { p0r = slen - 1; } if (p0r < 0) p0r = 0; int p1r = p0r + 1; if (p1r >= slen) p1r = sv->loop ? 0 : p0r; if (p0r >= smax || p1r >= smax) { sv->active = 0; return; } double fr = pos_r - p0r; double samp_r = buf[p0r] * (1.0 - fr) + buf[p1r] * fr;
double vol = sv->volume * sv->fade; double l_gain = sv->pan <= 0 ? 1.0 : 1.0 - sv->pan * 0.6; double r_gain = sv->pan >= 0 ? 1.0 : 1.0 + sv->pan * 0.6; *mix_l += samp_l * vol * l_gain; *mix_r += samp_r * vol * r_gain;
sv->position += sv->speed; if (sv->position >= slen) { if (sv->loop) { while (sv->position >= slen) sv->position -= slen; } else { sv->active = 0; } } else if (sv->position < 0.0) { if (sv->loop) { while (sv->position < 0.0) sv->position += slen; } else { sv->active = 0; } }}
static void *audio_thread_fn(void *arg) { ACAudio *audio = (ACAudio *)arg; const unsigned int period_frames = audio->actual_period ? audio->actual_period : AUDIO_PERIOD_SIZE; int16_t *buffer = calloc(period_frames * AUDIO_CHANNELS, sizeof(int16_t)); int32_t *buffer32 = NULL; if (audio->use_s32) buffer32 = calloc(period_frames * AUDIO_CHANNELS, sizeof(int32_t)); if (!buffer || (audio->use_s32 && !buffer32)) { fprintf(stderr, "[audio] thread: alloc failed\n"); return NULL; } const double rate = (double)(audio->actual_rate ? audio->actual_rate : AUDIO_SAMPLE_RATE); const double dt = 1.0 / rate; double mix_divisor = 1.0; // Smooth auto-mix (matches speaker.mjs) // Auto-mix smoothing: fast-ish attack, slower release to avoid zipper clicks. const double mix_att_coeff = 1.0 - exp(-1.0 / (0.004 * rate)); // ~4ms const double mix_rel_coeff = 1.0 - exp(-1.0 / (0.060 * rate)); // ~60ms
// Drum bus peak compressor — gives percussion proper "stacking" feel. // The drum bus sums additively (no auto-mix divide) so rapid hits // would otherwise saturate through soft_clip tanh, flattening peaks // and making each new hit sound QUIETER. A real peak compressor // with fast attack / slower release keeps the drum bus below ~0.95 // so transients retain impact AND the compressor recovers between // hits so each kick/snare feels punchy on its own. double drum_gain = 1.0; const double DRUM_THRESH = 0.95; // 5ms attack — slower than a 2ms beater transient so the first peak // of each hit passes through at full amplitude before compression // engages. This preserves the "snap" of each individual kick/snare. const double drum_att_coeff = 1.0 - exp(-1.0 / (0.005 * rate)); // 200ms release — recovers quickly enough that successive hits at // typical tempos (120-200 BPM, 300-500ms between hits) each get // the benefit of full dynamic range. const double drum_rel_coeff = 1.0 - exp(-1.0 / (0.200 * rate));
// Set real-time priority to prevent audio glitches from background tasks struct sched_param sp = { .sched_priority = 50 }; if (pthread_setschedparam(pthread_self(), SCHED_FIFO, &sp) != 0) fprintf(stderr, "[audio] Warning: couldn't set RT priority\n");
/* Pin the audio thread to the last online CPU. CPU 0 typically * services timer/network/USB IRQs; isolating audio on a separate * core tightens the jitter ceiling without affecting median. * Disable with AC_AUDIO_NO_PIN=1 if it conflicts with isolcpus. */ if (!getenv("AC_AUDIO_NO_PIN")) { long ncpu = sysconf(_SC_NPROCESSORS_ONLN); if (ncpu > 1) { int target = (int)(ncpu - 1); cpu_set_t cs; CPU_ZERO(&cs); CPU_SET(target, &cs); if (pthread_setaffinity_np(pthread_self(), sizeof(cs), &cs) != 0) fprintf(stderr, "[audio] Warning: couldn't pin audio thread to CPU %d\n", target); else fprintf(stderr, "[audio] Pinned to CPU %d (of %ld online)\n", target, ncpu); } }
/* Optional jitter benchmark: AC_LATENCY_BENCH=1 makes the audio * thread record per-period wall-clock intervals and emit a * single-line stats summary every PERIODS_PER_REPORT iterations. * Output format (one line per report, parseable by latency.mjs): * [ac-latency] period_us=<expected> n=<count> min=<us> p50=<us> * mean=<us> p99=<us> max=<us> over_period_us=<count> xruns=<count> */ const int latency_bench = getenv("AC_LATENCY_BENCH") && getenv("AC_LATENCY_BENCH")[0] == '1'; const int PERIODS_PER_REPORT = 1024; long expected_period_us = (long)(((double)period_frames / (double)rate) * 1e6); /* Keep a small ring of recent intervals so we can compute p50/p99 * without storing every sample for the lifetime of the program. */ long *bench_us = NULL; int bench_count = 0; long bench_min = LONG_MAX, bench_max = 0, bench_sum = 0; long bench_over_period = 0; // periods that took > 1.5x expected struct timespec bench_prev_ts = {0}; if (latency_bench) { bench_us = (long *)calloc(PERIODS_PER_REPORT, sizeof(long)); /* bench_prev_ts left at {0,0} — set on first iteration below * so the first delta is skipped (it would include startup * prefill, not a real period interval). */ fprintf(stderr, "[ac-latency] benchmark enabled — period_us=%ld report=%d periods\n", expected_period_us, PERIODS_PER_REPORT); }
while (audio->running) { // `buffer` is a pointer, so sizeof cleared 8 bytes, not the period. // The s16 path happens to assign every slot before use, which is why // nothing was audibly wrong; the s32 path reads the whole buffer. memset(buffer, 0, period_frames * AUDIO_CHANNELS * sizeof(buffer[0]));
pthread_mutex_lock(&audio->lock);
for (unsigned int i = 0; i < period_frames; i++) { // Split the voice bus in two: TONES get auto-mix normalization // (divide by total voice weight so held chords stay balanced), // DRUMS stack additively (so a kick+snare+hat transient sums to // a louder peak instead of ducking itself). soft_clip at the end // catches any drum peak excess with tanh saturation — which // gives percussion a natural analog "push" character. // // Heuristic: a voice is percussive if it has a SHORT FINITE // duration (< 0.5s). Held tones (duration = Infinity) and // long one-shot tones always go through the auto-mix bus. double tone_l = 0.0, tone_r = 0.0; double drum_l = 0.0, drum_r = 0.0; double voice_sum = 0.0; // Tone-only voice weight for auto-mix
for (int v = 0; v < AUDIO_MAX_VOICES; v++) { ACVoice *voice = &audio->voices[v]; if (voice->state == VOICE_INACTIVE) continue;
double s = generate_sample(voice, rate); double env = compute_envelope(voice); double fade = compute_fade(voice); double amp = s * env * fade * voice->volume;
double left_gain = (1.0 - voice->pan) * 0.5; double right_gain = (1.0 + voice->pan) * 0.5;
int is_percussive = !isinf(voice->duration) && voice->duration < 0.5; if (is_percussive) { // Drum bus — no auto-mix normalization. Drums stack // additively and rely on soft_clip for peak control. drum_l += amp * left_gain; drum_r += amp * right_gain; } else { // Tone bus — contributes to voice_sum for auto-mix. tone_l += amp * left_gain; tone_r += amp * right_gain; if (voice->state == VOICE_KILLING) { voice_sum += voice->volume * (1.0 - voice->fade_elapsed / voice->fade_duration); } else { voice_sum += voice->volume; } }
voice->elapsed += dt; if (voice->state == VOICE_KILLING) { voice->fade_elapsed += dt; if (voice->fade_elapsed >= voice->fade_duration) voice->state = VOICE_INACTIVE; } else if (!isinf(voice->duration) && voice->elapsed >= voice->duration) { voice->state = VOICE_INACTIVE; } }
// Smooth auto-mix divisor — fast attack, slow release. // Applied ONLY to the tone bus. Drums bypass it entirely. double target = voice_sum > 1.0 ? voice_sum : 1.0; if (mix_divisor < target) mix_divisor += (target - mix_divisor) * mix_att_coeff; else if (mix_divisor > target) mix_divisor += (target - mix_divisor) * mix_rel_coeff; if (mix_divisor < 1.0) mix_divisor = 1.0;
tone_l /= mix_divisor; tone_r /= mix_divisor;
// Drum bus peak compressor: detect peak, attack fast if over // threshold, release slow. Unlike the tone auto-mix divide, // this preserves individual hit dynamics — a single drum hit // passes through at full amplitude, but sustained buildup // from overlapping hits gets gain-reduced gracefully so they // stack linearly instead of saturating through soft_clip. { double peak = fabs(drum_l); double peak_r = fabs(drum_r); if (peak_r > peak) peak = peak_r; double target = (peak > DRUM_THRESH) ? (DRUM_THRESH / peak) : 1.0; if (target < drum_gain) { drum_gain += (target - drum_gain) * drum_att_coeff; } else { drum_gain += (target - drum_gain) * drum_rel_coeff; } drum_l *= drum_gain; drum_r *= drum_gain; }
// Merge the two buses. Drums land compressed to ~0.95 peak // so they retain impact without saturating the final output. double mix_l = tone_l + drum_l; double mix_r = tone_r + drum_r;
// Mix sample voices (pitch-shifted playback) // Lock already held from line 246 — safe to read sample_buf for (int v = 0; v < AUDIO_MAX_SAMPLE_VOICES; v++) { SampleVoice *sv = &audio->sample_voices[v]; mix_sample_voice(sv, audio->sample_buf, audio->sample_len, audio->sample_max_len, rate, &mix_l, &mix_r); }
// Dedicated global replay voice. Uses its own buffer so reverse // playback can overlap normal sample-bank activity. mix_sample_voice(&audio->replay_voice, audio->replay_buf, audio->replay_len, audio->replay_max_len, rate, &mix_l, &mix_r); // (lock released at end of buffer loop)
// Mix the named one-shot bank voices (zoo / lasers). Each voice // points at its own buffer in oneshot_bank[]; up to // ONESHOT_MAX_VOICES concurrent. mix_oneshot_voices(rate, &mix_l, &mix_r);
// Drum-skin friction. After the modal strikes, on the same bus, so // a rub and a hit land in the same room. mix_scratch(audio, rate, &mix_l, &mix_r);
// Mix DJ deck audio (lock-free: single consumer = audio thread) // Speed control: advance ring read by `speed` samples per output sample // with linear interpolation for smooth pitch shifting / scratching. for (int d = 0; d < AUDIO_MAX_DECKS; d++) { ACDeck *dk = &audio->decks[d]; if (!dk->active || !dk->playing || !dk->decoder) continue; ACDeckDecoder *dec = dk->decoder; double spd = dec->speed; if (spd < -4.0) spd = -4.0; if (spd > 4.0) spd = 4.0; int64_t avail = dec->ring_write - dec->ring_read; if (avail <= 1) continue; // Fractional ring position for interpolation double frac_pos = dec->ring_frac; int64_t base = dec->ring_read; int64_t idx0 = base + (int64_t)frac_pos; if (idx0 < base || idx0 + 1 >= dec->ring_write) { // Not enough data — skip continue; } double t = frac_pos - (int64_t)frac_pos; int ri0 = (idx0 % dec->ring_size) * 2; int ri1 = ((idx0 + 1) % dec->ring_size) * 2; float sl = dec->ring[ri0] * (1.0f - (float)t) + dec->ring[ri1] * (float)t; float sr = dec->ring[ri0 + 1] * (1.0f - (float)t) + dec->ring[ri1 + 1] * (float)t; // Advance fractional position by speed dec->ring_frac += spd; // Consume whole samples from ring int consumed = (int)dec->ring_frac; if (consumed > 0) { dec->ring_read += consumed; dec->ring_frac -= consumed; } else if (consumed < 0) { // Reverse: clamp to not go before ring_read // (reverse scratching won't replay old audio, just stops) dec->ring_frac = 0; } // Crossfader: 0.0 = full deck A, 1.0 = full deck B float cf = (d == 0) ? (1.0f - audio->crossfader) : audio->crossfader; float vol = dk->volume * cf * audio->deck_master_volume; mix_l += sl * vol; mix_r += sr * vol; // Wake the decoder if the ring drained below 50%, but only on // the first frame of the period. This check sits in the // per-SAMPLE loop: at 192kHz a draining deck was taking a // mutex and signalling a condvar up to 192,000 times a second // from the SCHED_FIFO thread, which is a futex storm on the // one thread that must never block. Once per period is 1ms // granularity — far faster than the decoder can refill, and // three orders of magnitude fewer syscalls. if (i == 0 && (dec->ring_write - dec->ring_read) < dec->ring_size / 2) { pthread_mutex_lock(&dec->mutex); pthread_cond_signal(&dec->cond); pthread_mutex_unlock(&dec->mutex); } }
// Smooth room_mix toward target (~10ms at 192kHz) if (audio->room_mix != audio->target_room_mix) { audio->room_mix += (audio->target_room_mix - audio->room_mix) * 0.00005f; }
// Smooth fx_mix toward target if (audio->fx_mix != audio->target_fx_mix) { audio->fx_mix += (audio->target_fx_mix - audio->fx_mix) * 0.00005f; }
// Smooth bitcrush mix toward target if (audio->glitch_mix != audio->target_glitch_mix) { audio->glitch_mix += (audio->target_glitch_mix - audio->glitch_mix) * 0.00005f; }
// Smooth master volume + drive toward target (same 1s time const) if (audio->master_volume != audio->target_master_volume) { audio->master_volume += (audio->target_master_volume - audio->master_volume) * 0.00005f; } if (audio->drive_mix != audio->target_drive_mix) { audio->drive_mix += (audio->target_drive_mix - audio->drive_mix) * 0.00005f; } if (audio->wobble_mix != audio->target_wobble_mix) { audio->wobble_mix += (audio->target_wobble_mix - audio->wobble_mix) * 0.00005f; }
// Save dry signal before FX chain double dry_l = mix_l, dry_r = mix_r;
// Capture recent dry output for true reverse replay. This stores // the actual mixed audio (not note events) before room/glitch/TTS // so the reverse replay can run back through the live FX chain. // // When `output_history_paused` is set (by notepat while spacebar // is held), we skip this write entirely — the reverse-playback // voice being fed back through the speaker mix would otherwise // re-enter the ring and double-layer on the original audio. The // pause ONLY affects capture; the ring contents and read_pos // are untouched so replay continues from the existing snapshot. if (audio->output_history_buf && audio->output_history_size > 0 && !audio->output_history_paused) { unsigned int stride = audio->output_history_downsample_n; if (stride == 0) stride = 1; audio->output_history_downsample_pos++; if (audio->output_history_downsample_pos >= stride) { audio->output_history_downsample_pos = 0; uint64_t wp = audio->output_history_write_pos; audio->output_history_buf[wp % (uint64_t)audio->output_history_size] = (float)((dry_l + dry_r) * 0.5); audio->output_history_write_pos = wp + 1; } }
// Room (reverb) effect — tap delays based on actual sample rate if (audio->room_enabled && audio->room_buf_l) { float rmix = audio->room_mix; int rs = audio->room_size;
// At 0% mix, skip all reverb processing (no buffer feed, no output) if (rmix > 0.001f) { int room_delay = (int)(0.12 * rate); // 120ms in samples int tap1 = (audio->room_pos - room_delay + rs) % rs; int tap2 = (audio->room_pos - room_delay * 2 + rs) % rs; int tap3 = (audio->room_pos - room_delay * 3 + rs) % rs;
// Weighted sum of taps, normalized float wet_l = (audio->room_buf_l[tap1] * 0.5f + audio->room_buf_l[tap2] * 0.3f + audio->room_buf_l[tap3] * 0.2f); float wet_r = (audio->room_buf_r[tap1] * 0.5f + audio->room_buf_r[tap2] * 0.3f + audio->room_buf_r[tap3] * 0.2f);
// Feed buffer: dry input + attenuated wet feedback float fb_l = (float)mix_l + wet_l * ROOM_FEEDBACK; float fb_r = (float)mix_r + wet_r * ROOM_FEEDBACK; // Damping — ensures reverb tail always decays fb_l *= 0.995f; fb_r *= 0.995f; // Soft-limit feedback to avoid hard-clamp discontinuities under transients. fb_l = tanhf(fb_l * 0.65f) / 0.65f; fb_r = tanhf(fb_r * 0.65f) / 0.65f; audio->room_buf_l[audio->room_pos] = fb_l; audio->room_buf_r[audio->room_pos] = fb_r;
// Mix wet into output mix_l = mix_l * (1.0 - rmix) + wet_l * rmix; mix_r = mix_r * (1.0 - rmix) + wet_r * rmix; } else { // Mix is ~0%: just clear the current buffer position (drain residue) audio->room_buf_l[audio->room_pos] = 0.0f; audio->room_buf_r[audio->room_pos] = 0.0f; } audio->room_pos = (audio->room_pos + 1) % rs; }
// Glitch (sample-hold + bitcrush) // `glitch_mix` scales the intensity of the stage itself, while // `fx_mix` still controls the dry/wet blend of the whole FX chain. { float gmix = audio->glitch_mix; if (gmix > 0.001f) { float crush = gmix * gmix; int hold_interval = 1 + (int)roundf((float)(audio->glitch_rate - 1) * crush); int bits = 12 - (int)roundf(gmix * 8.0f); // 12-bit -> 4-bit if (bits < 4) bits = 4; if (bits > 12) bits = 12; int levels = 1 << bits;
audio->glitch_counter++; if (audio->glitch_counter >= hold_interval) { audio->glitch_counter = 0; audio->glitch_hold_l = roundf((float)mix_l * levels) / levels; audio->glitch_hold_r = roundf((float)mix_r * levels) / levels; }
mix_l = mix_l * (1.0f - gmix) + audio->glitch_hold_l * gmix; mix_r = mix_r * (1.0f - gmix) + audio->glitch_hold_r * gmix; } }
// Blend dry/wet based on FX mix { float fxm = audio->fx_mix; if (fxm < 0.999f) { mix_l = dry_l * (1.0 - fxm) + mix_l * fxm; mix_r = dry_r * (1.0 - fxm) + mix_r * fxm; } }
// Mix in TTS audio after FX chain (bypasses reverb/glitch) // Fade envelope prevents hard-start/stop clicks { int tts_has_data = audio->tts_buf && (audio->tts_read_pos != audio->tts_write_pos); // ~3ms ramp at 192kHz (1/576 per sample) float ramp = 1.0f / 576.0f; if (tts_has_data) { audio->tts_fade += ramp; if (audio->tts_fade > 1.0f) audio->tts_fade = 1.0f; float tts_sample = audio->tts_buf[audio->tts_read_pos] * audio->tts_volume * audio->tts_fade; mix_l += tts_sample; mix_r += tts_sample; audio->tts_read_pos = (audio->tts_read_pos + 1) % audio->tts_buf_size; } else { // Fade out: keep adding the last scaled zero-ish sample if (audio->tts_fade > 0.0f) { audio->tts_fade -= ramp; if (audio->tts_fade < 0.0f) audio->tts_fade = 0.0f; } } }
// Compressor: peak-following gain reduction (threshold 0.4, ratio ~8:1) { double peak = fabs(mix_l); double pr = fabs(mix_r); if (pr > peak) peak = pr; // Attack: very fast (0.2ms), Release: medium (40ms) double att_coeff = 1.0 - exp(-1.0 / (0.0002 * rate)); double rel_coeff = 1.0 - exp(-1.0 / (0.04 * rate)); if (peak > comp_env) comp_env += att_coeff * (peak - comp_env); else comp_env += rel_coeff * (peak - comp_env); if (comp_env > 0.4) { double gain = 0.4 + (comp_env - 0.4) * 0.125; // ~8:1 ratio above threshold double reduction = gain / comp_env; mix_l *= reduction; mix_r *= reduction; } }
// Wobble / flange — modulated short-delay blend. Writes every // sample into the ring regardless of wet mix (so the ring // stays warm for instant-on when the slider turns up), then // reads a sample `delay_samples` behind the write head with // the delay itself sweeping via a slow LFO. Tiny feedback // (0.45) thickens the tail so moderate mix settings already // produce the characteristic jet-sweep coloration. if (audio->wobble_buf_l && audio->wobble_buf_size > 0) { int size = audio->wobble_buf_size; int mask = size - 1; // size is power of two (1024) int wp = audio->wobble_write_pos; float wmix = audio->wobble_mix; // Sweep: 2-10 ms at 48 kHz = 96..480 samples. float lfo = (float)sin((double)audio->wobble_lfo_phase); float delay_samples = 96.0f + (lfo * 0.5f + 0.5f) * 384.0f; audio->wobble_lfo_phase += audio->wobble_lfo_rate; if (audio->wobble_lfo_phase > 6.283185307179586f) audio->wobble_lfo_phase -= 6.283185307179586f; // Fractional read with linear interp. float rp = (float)wp - delay_samples; while (rp < 0) rp += size; int rp_i = (int)rp; float rp_f = rp - (float)rp_i; float dly_l = audio->wobble_buf_l[rp_i & mask] * (1.0f - rp_f) + audio->wobble_buf_l[(rp_i + 1) & mask] * rp_f; float dly_r = audio->wobble_buf_r[rp_i & mask] * (1.0f - rp_f) + audio->wobble_buf_r[(rp_i + 1) & mask] * rp_f; // Feedback into the ring (for sustained "zing"). audio->wobble_buf_l[wp & mask] = (float)mix_l + dly_l * 0.45f; audio->wobble_buf_r[wp & mask] = (float)mix_r + dly_r * 0.45f; audio->wobble_write_pos = (wp + 1) & mask; if (wmix > 0.001f) { mix_l = mix_l * (1.0 - wmix) + (double)dly_l * wmix; mix_r = mix_r * (1.0 - wmix) + (double)dly_r * wmix; } }
// User-controlled drive (tanh soft-saturation) BEFORE system // volume so the harmonic character is independent of hardware // gain. drive_mix is a dry/wet blend: 0 = pure bypass, 1 = fully // driven (pre-gain × 6 into tanh, attenuated back to roughly // unity peak). At mid settings you get pleasing tube-ish warmth. if (audio->drive_mix > 0.001f) { float dm = audio->drive_mix; float pre_gain = 1.0f + dm * 5.0f; double driven_l = tanh(mix_l * pre_gain) * 0.8; double driven_r = tanh(mix_r * pre_gain) * 0.8; mix_l = mix_l * (1.0 - dm) + driven_l * dm; mix_r = mix_r * (1.0 - dm) + driven_r * dm; }
// User-controlled master volume (0..2 = 0..200%). Applied after // drive so the slider feels like a "louder/quieter" control that // doesn't change the tone character the user dialled in. { float mv = audio->master_volume; mix_l *= mv; mix_r *= mv; }
// Apply system volume (software gain). system_volume can go // above 100 on SOF cards where the DSP pipeline has -6dB+ // headroom and the amp needs boosting to reach normal levels. // -1 means no Master mixer found — treat as 100% baseline. { int sv = audio->system_volume; if (sv < 0) sv = 100; double vol = sv * 0.01; // 0..4 (up to 400% → 16× linear) vol = vol * vol; // squared curve mix_l *= vol; mix_r *= vol; }
// Mono fold: sum the channels at -3 dB, in place, when asked. // A plain average puts a hard-panned voice 6 dB down ("way too // quiet" — Menu Band's fold moved to (L+R)/sqrt(2) for the same // reason); the soft clip right after keeps the sum below full // scale. if (audio->mono) { float m = 0.70710678f * (mix_l + mix_r); mix_l = m; mix_r = m; }
// Soft clip and convert to int16 mix_l = soft_clip(mix_l); mix_r = soft_clip(mix_r);
/* 32000 = ~97% of int16 max. Was 26000 (~79%), wasting * ~2dB of peak output. Combined with higher soft_clip * knee this gives ~4dB more audible loudness before any * compression artifacts. */ buffer[i * 2] = (int16_t)(mix_l * 32000); buffer[i * 2 + 1] = (int16_t)(mix_r * 32000);
/* DAPM keepalive: inject low-frequency dither (alternating * every 8 samples = 3kHz, well below 24kHz Nyquist edge). * ±8 int16 → ±2048 int32 ≈ -72 dBFS, inaudible through * DAC anti-alias filter. Previous ±32 @ 24kHz alternation * leaked through as faint hiss at high gain. */ if (buffer[i * 2] == 0 && buffer[i * 2 + 1] == 0) { int16_t d = ((i >> 3) & 1) ? 8 : -8; buffer[i * 2] = d; buffer[i * 2 + 1] = -d; }
// HDMI audio: 1-pole low-pass filter + downsample // (volume already applied above to mix_l/mix_r) if (audio->hdmi_pcm) { // LP filter (alpha ≈ 0.18 → ~3kHz cutoff at 48kHz) float alpha = 0.18f; audio->hdmi_lp_l = alpha * (float)mix_l + (1.0f - alpha) * audio->hdmi_lp_l; audio->hdmi_lp_r = alpha * (float)mix_r + (1.0f - alpha) * audio->hdmi_lp_r; // Downsample: one HDMI sample per N primary samples audio->hdmi_downsample_pos++; if (audio->hdmi_downsample_pos >= audio->hdmi_downsample_n) { audio->hdmi_downsample_pos = 0; int pp = audio->hdmi_period_pos; if (pp + 1 < (int)(sizeof(audio->hdmi_period) / sizeof(int16_t)) / 2) { audio->hdmi_period[pp * 2] = (int16_t)(audio->hdmi_lp_l * 28000); audio->hdmi_period[pp * 2 + 1] = (int16_t)(audio->hdmi_lp_r * 28000); audio->hdmi_period_pos++; if (audio->hdmi_period_pos >= audio->hdmi_period_size) { snd_pcm_t *hpcm = (snd_pcm_t *)audio->hdmi_pcm; int hw = snd_pcm_writei(hpcm, audio->hdmi_period, audio->hdmi_period_size); if (hw == -EPIPE || hw == -ESTRPIPE) snd_pcm_recover(hpcm, hw, 1); audio->hdmi_period_pos = 0; } } } }
// Store waveform for visualization int wp = audio->waveform_pos; audio->waveform_left[wp] = (float)mix_l; audio->waveform_right[wp] = (float)mix_r; audio->waveform_pos = (wp + 1) % AUDIO_WAVEFORM_SIZE;
// Track amplitude float al = fabsf((float)mix_l); float ar = fabsf((float)mix_r); audio->amplitude_left = audio->amplitude_left * 0.99f + al * 0.01f; audio->amplitude_right = audio->amplitude_right * 0.99f + ar * 0.01f; }
// BPM metronome audio->beat_elapsed += (double)period_frames * dt; double beat_interval = 60.0 / audio->bpm; if (audio->beat_elapsed >= beat_interval) { audio->beat_elapsed -= beat_interval; audio->beat_triggered = 1; }
pthread_mutex_unlock(&audio->lock);
audio->total_frames += period_frames; audio->time = (double)audio->total_frames / rate;
// Recording tap: send mixed PCM to recorder (if active). Used by // the MP4 tape recorder (recorder.c) for the audio track. if (audio->rec_callback) audio->rec_callback(buffer, period_frames, audio->rec_userdata);
// Write to ALSA (handle short writes to avoid dropped samples/clicks) snd_pcm_t *pcm = (snd_pcm_t *)audio->pcm; /* Tee to parallel PCM (sof-rt5682+max98360a auto-route). * Best-effort, never blocks the primary write — short writes, * EPIPE underruns, and even outright failures are tolerated * because the *real* output is the primary PCM. The DAPM * jack-sense in the codec mutes whichever side isn't being * driven by the active jack state. */ snd_pcm_t *pcm2 = (snd_pcm_t *)audio->headphone_pcm; if (pcm2) { int rem2 = (int)period_frames; int off2 = 0; while (rem2 > 0) { int f2 = snd_pcm_writei(pcm2, buffer + off2 * AUDIO_CHANNELS, rem2); if (f2 == -EAGAIN) break; /* don't spin on secondary */ if (f2 < 0) { snd_pcm_recover(pcm2, f2, 1); break; } rem2 -= f2; off2 += f2; } } /* Widen int16→int32 for S32_LE PCMs (SOF topology). * The SSP1 BE DAI runs S24_LE. SOF DSP uses the bottom 24 * bits of the S32 container (bits 23:0). Shifting int16 by * 8 places our 16-bit audio in bits 23:8, which fills the * top portion of the 24-bit window — correct for S24-in-S32 * bottom-aligned format. (<<16 put data in bits 31:16 which * the DSP's 24-bit window barely saw → super quiet.) */ const void *write_buf = buffer; if (buffer32) { for (int j = 0; j < (int)(period_frames * AUDIO_CHANNELS); j++) buffer32[j] = (int32_t)buffer[j] << 8; write_buf = buffer32; } int remaining = (int)period_frames; int offset = 0; while (remaining > 0) { const void *wptr = buffer32 ? (const void *)(buffer32 + offset * AUDIO_CHANNELS) : (const void *)(buffer + offset * AUDIO_CHANNELS); /* mmap_writei skips a buffer copy versus writei; falls * through to writei when access wasn't negotiated as * MMAP_INTERLEAVED. */ int frames = audio->use_mmap ? snd_pcm_mmap_writei(pcm, wptr, remaining) : snd_pcm_writei(pcm, wptr, remaining); if (frames == -EAGAIN) continue; if (frames < 0) { int rec = snd_pcm_recover(pcm, frames, 1); if (frames == -EPIPE || frames == -ESTRPIPE) { xrun_count++; if ((xrun_count % 32) == 1) { fprintf(stderr, "[audio] XRUN recovered x%lu\n", xrun_count); } } if (rec < 0) { fprintf(stderr, "[audio] ALSA write failed: %s\n", snd_strerror(rec)); break; } continue; } if (frames == 0) continue; if (frames < remaining) { short_write_count++; if ((short_write_count % 64) == 1) { fprintf(stderr, "[audio] Short write x%lu (%d/%d)\n", short_write_count, frames, remaining); } } remaining -= frames; offset += frames; }
/* Per-period jitter measurement (AC_LATENCY_BENCH=1). * Time between successive writei completions = actual delivered * period. Compare to expected to expose audio-thread scheduling * jitter — the empirical floor for audio-side latency. */ if (latency_bench && bench_us) { struct timespec now_ts; clock_gettime(CLOCK_MONOTONIC, &now_ts); if (bench_prev_ts.tv_sec == 0 && bench_prev_ts.tv_nsec == 0) { /* First iteration — establish the time origin and skip; * the first delta would include startup prefill. */ bench_prev_ts = now_ts; } else { long delta_us = (now_ts.tv_sec - bench_prev_ts.tv_sec) * 1000000L + (now_ts.tv_nsec - bench_prev_ts.tv_nsec) / 1000L; bench_prev_ts = now_ts; bench_us[bench_count] = delta_us; if (delta_us < bench_min) bench_min = delta_us; if (delta_us > bench_max) bench_max = delta_us; bench_sum += delta_us; if (delta_us > expected_period_us * 3 / 2) bench_over_period++; bench_count++; } if (bench_count >= PERIODS_PER_REPORT) { /* qsort to compute p50/p99. n=1024 → ~10k comparisons, * runs in tens of µs once per second of audio — well * under one period budget on the RT audio thread. */ int n = bench_count; qsort(bench_us, n, sizeof(long), bench_cmp_long); long p50 = bench_us[n / 2]; long p99 = bench_us[(int)(n * 0.99)]; long mean = bench_sum / n; fprintf(stderr, "[ac-latency] period_us=%ld n=%d min=%ld p50=%ld mean=%ld p99=%ld max=%ld over_period=%ld xruns=%lu\n", expected_period_us, n, bench_min, p50, mean, p99, bench_max, bench_over_period, xrun_count); bench_count = 0; bench_min = LONG_MAX; bench_max = 0; bench_sum = 0; bench_over_period = 0; } } }
free(bench_us); free(buffer); free(buffer32); return NULL;}
// ============================================================// Public API// ============================================================
// Seed a small default sample so sample mode is playable before first mic recording.// This roughly matches the "startup" one-shot feel used in web notepat.static void seed_default_sample(ACAudio *audio) { if (!audio || !audio->sample_buf || audio->sample_max_len <= 0) return;
const unsigned int rate = 48000; int len = (int)(0.55 * (double)rate); // 550ms one-shot if (len > audio->sample_max_len) len = audio->sample_max_len;
double p1 = 0.0, p2 = 0.0, p3 = 0.0; for (int i = 0; i < len; i++) { double t = (double)i / (double)rate; double env = exp(-6.0 * t) * (1.0 - exp(-35.0 * t)); // fast attack, exponential decay double f0 = 240.0 + 50.0 * sin(t * 6.0); // slight wobble double f1 = f0 * 2.01; double f2 = f0 * 3.02; p1 += 2.0 * M_PI * f0 / (double)rate; p2 += 2.0 * M_PI * f1 / (double)rate; p3 += 2.0 * M_PI * f2 / (double)rate;
double s = 0.78 * sin(p1) + 0.22 * sin(p2 + 0.25) + 0.08 * sin(p3 + 0.15); audio->sample_buf[i] = (float)(s * env * 0.85); } for (int i = len; i < audio->sample_max_len; i++) audio->sample_buf[i] = 0.0f;
audio->sample_len = len; audio->sample_rate = rate; ac_log("[sample] seeded default startup sample (%d frames @ %u Hz)\n", audio->sample_len, audio->sample_rate);}
ACAudio *audio_init(void) { ACAudio *audio = calloc(1, sizeof(ACAudio)); if (!audio) return NULL;
audio->bpm = 120.0; audio->actual_rate = AUDIO_SAMPLE_RATE; // default, overwritten after ALSA negotiation audio->glitch_rate = AUDIO_SAMPLE_RATE / 1600; // Priority inheritance is not optional here. The render thread runs // SCHED_FIFO and holds this lock across a whole period, while sixteen // main-thread call sites reach for it to change synth state. With a plain // mutex, the RT thread can block on a lock owned by a normal-priority // thread that the scheduler is in no hurry to run — textbook priority // inversion, at a 1ms deadline. Missing that deadline is the audible // tearing / underrun already noted in PROGRESS.md. Inheritance lifts the // holder to the waiter's priority so it finishes and releases promptly. { pthread_mutexattr_t attr; if (pthread_mutexattr_init(&attr) == 0) { if (pthread_mutexattr_setprotocol(&attr, PTHREAD_PRIO_INHERIT) != 0) ac_log("[audio] PRIO_INHERIT unavailable — mutex stays plain\n"); pthread_mutex_init(&audio->lock, &attr); pthread_mutexattr_destroy(&attr); } else { pthread_mutex_init(&audio->lock, NULL); } }
// Build the sine wavetable used by the GM modal/FM voices (idempotent). gm_synth_init();
// The friction voice's defaults are not all zero (a zero release time is // an instant cut, not a release), and calloc cannot know that. scratch_voice_init(&audio->scratch);
// Load piano sample bank from /samples/piano/. Idempotent: safe to // call from both audio_init paths in ac-native.c. Bank is global // (not on the audio struct) since it's read-only once loaded. static int piano_bank_loaded = 0; if (!piano_bank_loaded) { load_piano_bank(); piano_bank_loaded = 1; }
// Load the named one-shot bank (zoo + lasers + future kits). Global, // process-lifetime, idempotent — same pattern as the piano bank. static int oneshot_bank_loaded = 0; if (!oneshot_bank_loaded) { load_oneshot_bank(); oneshot_bank_loaded = 1; } // Voice slots are static, just make sure no stale state leaks in. for (int i = 0; i < ONESHOT_MAX_VOICES; i++) { oneshot_voices[i].active = 0; }
// Allocate reverb buffers audio->room_size = ROOM_SIZE; audio->room_mix = 0.0f; // Start dry, trackpad Y controls audio->room_enabled = 1; // Always on, mix controls wet amount audio->glitch_mix = 0.0f; audio->target_glitch_mix = 0.0f; audio->fx_mix = 1.0f; // FX chain fully wet by default audio->target_fx_mix = 1.0f; // User master volume starts at 1.0 (unity gain) — the pre-existing // system_volume path still provides the hardware mixer control, so // this is a per-user soft gain on top. audio->master_volume = 1.0f; audio->target_master_volume = 1.0f; audio->drive_mix = 0.0f; // Clean bypass until user dials drive audio->target_drive_mix = 0.0f; // Wobble / flange — 1024-sample ring covers up to ~21 ms @ 48 kHz // which is well past the flanger sweet spot (1-10 ms). Power-of-two // size lets the read index use `& (size-1)` instead of `%`. audio->wobble_buf_size = 1024; audio->wobble_buf_l = calloc(audio->wobble_buf_size, sizeof(float)); audio->wobble_buf_r = calloc(audio->wobble_buf_size, sizeof(float)); audio->wobble_write_pos = 0; audio->wobble_lfo_phase = 0.0f; // LFO rate 0.4 Hz — slow sweep, reads as "wobble" not "chorus" audio->wobble_lfo_rate = 2.0f * 3.14159265358979f * 0.4f / 48000.0f; audio->wobble_mix = 0.0f; audio->target_wobble_mix = 0.0f; audio->room_buf_l = calloc(ROOM_SIZE, sizeof(float)); audio->room_buf_r = calloc(ROOM_SIZE, sizeof(float));
// Sample buffer (10 seconds at max 48kHz capture rate) audio->sample_max_len = 48000 * AUDIO_MAX_SAMPLE_SECS; audio->sample_buf = calloc(audio->sample_max_len, sizeof(float)); audio->sample_buf_back = calloc(audio->sample_max_len, sizeof(float)); audio->sample_len = 0; audio->sample_rate = 48000; // default, overwritten by actual capture rate audio->sample_next_id = 1; audio->replay_max_len = AUDIO_OUTPUT_HISTORY_RATE * AUDIO_OUTPUT_HISTORY_SECS; audio->replay_buf = calloc(audio->replay_max_len, sizeof(float)); audio->replay_buf_back = calloc(audio->replay_max_len, sizeof(float)); audio->replay_len = 0; audio->replay_rate = AUDIO_OUTPUT_HISTORY_RATE; memset(&audio->replay_voice, 0, sizeof(audio->replay_voice)); audio->mic_connected = 0; audio->mic_hot = 0; audio->mic_level = 0.0f; audio->mic_last_chunk = 0; audio->capture_thread_running = 0; memset(audio->mic_waveform, 0, sizeof(audio->mic_waveform)); audio->mic_waveform_pos = 0; audio->mic_ring = calloc(audio->sample_max_len, sizeof(float)); audio->mic_ring_pos = 0; audio->rec_start_ring_pos = 0; audio->output_history_buf = calloc(AUDIO_OUTPUT_HISTORY_RATE * AUDIO_OUTPUT_HISTORY_SECS, sizeof(float)); audio->output_history_size = AUDIO_OUTPUT_HISTORY_RATE * AUDIO_OUTPUT_HISTORY_SECS; audio->output_history_rate = AUDIO_OUTPUT_HISTORY_RATE; audio->output_history_downsample_n = 1; audio->output_history_downsample_pos = 0; audio->output_history_write_pos = 0; snprintf(audio->mic_device, sizeof(audio->mic_device), "none"); audio->mic_last_error[0] = 0; seed_default_sample(audio);
// DJ decks: initialize with default volumes audio->crossfader = 0.5f; // centered audio->deck_master_volume = 0.8f; // default master for (int d = 0; d < AUDIO_MAX_DECKS; d++) { audio->decks[d].active = 0; audio->decks[d].playing = 0; audio->decks[d].volume = 1.0f; audio->decks[d].decoder = NULL; }
// TTS PCM ring buffer (5 seconds at max output rate) audio->tts_buf_size = AUDIO_SAMPLE_RATE * 5; // allocated at max, actual_rate adjusts usage audio->tts_buf = calloc(audio->tts_buf_size, sizeof(float)); audio->tts_read_pos = 0; audio->tts_write_pos = 0; audio->tts_volume = 2.5f; // Boost flite output (naturally quiet)
snprintf(audio->audio_device, sizeof(audio->audio_device), "none"); snprintf(audio->audio_status, sizeof(audio->audio_status), "initializing"); audio->audio_init_retries = 0;
// Wait for sound card to appear fprintf(stderr, "[audio] Waiting for sound card...\n"); int card_found = 0; for (int w = 0; w < 400; w++) { // up to 8 seconds if (access("/dev/snd/pcmC0D0p", F_OK) == 0 || access("/dev/snd/pcmC1D0p", F_OK) == 0 || access("/dev/snd/pcmC2D0p", F_OK) == 0) { card_found = 1; break; } usleep(20000); } if (!card_found) { // Distinguish: HDA controller present (codec probe failed) vs no hardware at all if (access("/dev/snd/controlC0", F_OK) == 0) { fprintf(stderr, "[audio] WARNING: HDA controller present but codec not probed after 8s\n"); snprintf(audio->audio_status, sizeof(audio->audio_status), "HDA ctrl ok, codec not probed"); } else { fprintf(stderr, "[audio] WARNING: no sound card after 8s wait\n"); snprintf(audio->audio_status, sizeof(audio->audio_status), "no card (8s timeout)"); } }
// Dump sound card info for diagnostics (write to USB log if mounted) FILE *alog = fopen("/mnt/ac-audio.log", "w"); if (!alog) alog = stderr; // fallback to stderr { FILE *cards = fopen("/proc/asound/cards", "r"); if (cards) { char line[256]; fprintf(alog, "[audio] === /proc/asound/cards ===\n"); while (fgets(line, sizeof(line), cards)) fprintf(alog, "[audio] %s", line); fclose(cards); } else { fprintf(alog, "[audio] WARNING: /proc/asound/cards not found!\n"); } // Also check /dev/snd/ DIR *snddir = opendir("/dev/snd"); if (snddir) { struct dirent *ent; fprintf(alog, "[audio] /dev/snd/:"); while ((ent = readdir(snddir))) { if (ent->d_name[0] != '.') fprintf(alog, " %s", ent->d_name); } fprintf(alog, "\n"); closedir(snddir); } else { fprintf(alog, "[audio] WARNING: /dev/snd/ not found!\n"); } }
// Open ALSA — try multiple cards and devices, with retries for race conditions. // On fast NVMe boots the HDA codec may not be fully probed when we first try. // If AC_AUDIO_DEVICE is set, try it first (used for stream tee via asound.conf). snd_pcm_t *pcm = NULL;
// SOF rt5682+max98360a (G7/Drawcia and friends) splits playback across two // PCMs: SSP0 → RT5682 headphones (PCM 0) and SSP1 → MAX98360A speakers // (PCM 1). The historical hw:0,0 default routes everything to headphones, // which is why speakers stayed silent even with the Speaker UCM verb fully // applied. Ask UCM what PCM it maps Speaker(s) to and try that FIRST so // playback hits the speaker amp by default; the headphone PCM still wins // if/when AC_AUDIO_DEVICE overrides or jack-sense flips routing later. char ucm_speaker_pcm[64] = ""; char ucm_headphone_pcm[64] = ""; { char card_id[32] = ""; int spk_card = 0; /* card index where Speaker UCM lives */ for (int c = 0; c < 4 && !card_id[0]; c++) { char p[64]; snprintf(p, sizeof(p), "/proc/asound/card%d/id", c); FILE *fp = fopen(p, "r"); if (fp) { if (fgets(card_id, sizeof(card_id), fp)) { char *nl = strchr(card_id, '\n'); if (nl) *nl = 0; } fclose(fp); if (card_id[0]) spk_card = c; } } if (card_id[0]) { const char *cands[] = { card_id, "sof-rt5682", "sof-cs42l42", "sof-nau8825", "sof-da7219", NULL }; snd_use_case_mgr_t *uc = NULL; for (int i = 0; cands[i] && (!ucm_speaker_pcm[0] || !ucm_headphone_pcm[0]); i++) { if (snd_use_case_mgr_open(&uc, cands[i]) != 0) continue; if (snd_use_case_set(uc, "_verb", "HiFi") == 0) { const char *spk_names[] = { "Speaker", "Speakers", NULL }; for (int s = 0; spk_names[s] && !ucm_speaker_pcm[0]; s++) { char id[64]; const char *val = NULL; snprintf(id, sizeof(id), "PlaybackPCM/%s", spk_names[s]); if (snd_use_case_get(uc, id, &val) == 0 && val) { /* UCM v2 returns strings like * "_ucm0002.hw:sofrt5682,0" — that is a * UCM-internal namespace tag, not a path * snd_pcm_open accepts. Strip the * "_ucmNNNN." prefix to get the underlying * "hw:CARD,DEV" form, then convert the card * id to a numeric index since snd_pcm_open * also rejects "hw:sofrt5682,0". */ const char *clean = val; const char *dot = strchr(clean, '.'); if (dot && strncmp(clean, "_ucm", 4) == 0) clean = dot + 1; const char *comma = strrchr(clean, ','); if (comma && strncmp(clean, "hw:", 3) == 0) { snprintf(ucm_speaker_pcm, sizeof(ucm_speaker_pcm), "hw:%d%s", spk_card, comma); } else { snprintf(ucm_speaker_pcm, sizeof(ucm_speaker_pcm), "%s", clean); } fprintf(stderr, "[audio] UCM Speaker PCM: raw=%s -> %s (%s/%s)\n", val, ucm_speaker_pcm, cands[i], spk_names[s]); free((void *)val); } } const char *hp_names[] = { "Headphone", "Headphones", "Headset", NULL }; for (int s = 0; hp_names[s] && !ucm_headphone_pcm[0]; s++) { char id[64]; const char *val = NULL; snprintf(id, sizeof(id), "PlaybackPCM/%s", hp_names[s]); if (snd_use_case_get(uc, id, &val) == 0 && val) { const char *clean = val; const char *dot = strchr(clean, '.'); if (dot && strncmp(clean, "_ucm", 4) == 0) clean = dot + 1; const char *comma = strrchr(clean, ','); if (comma && strncmp(clean, "hw:", 3) == 0) { snprintf(ucm_headphone_pcm, sizeof(ucm_headphone_pcm), "hw:%d%s", spk_card, comma); } else { snprintf(ucm_headphone_pcm, sizeof(ucm_headphone_pcm), "%s", clean); } fprintf(stderr, "[audio] UCM Headphone PCM: raw=%s -> %s (%s/%s)\n", val, ucm_headphone_pcm, cands[i], hp_names[s]); free((void *)val); } } } snd_use_case_mgr_close(uc); uc = NULL; } } }
/* Build the device probe list. If UCM gave us a Speaker PCM, prepend it * (and a `plug:` wrapped variant for rate negotiation safety). The legacy * fallback list still runs after, so non-SOF boards behave as before. */ const char *devices_default[] = { "hw:0,0", "hw:1,0", "hw:0,1", "hw:1,1", "hw:0,2", "hw:0,3", "hw:1,2", "hw:1,3", "plughw:0,0", "plughw:1,0", "default", NULL }; const char *devices_with_spk[16] = {0}; const char **devices = devices_default; char ucm_speaker_plug[80] = ""; if (ucm_speaker_pcm[0]) { snprintf(ucm_speaker_plug, sizeof(ucm_speaker_plug), "plughw%s", ucm_speaker_pcm + 2); /* hw:0,0 → plughw:0,0 */ int n = 0; /* Prefer raw hw: first — SOF topology FE PCM runs at S32_LE * internally, and we now negotiate S32_LE directly so the DSP * does zero conversion. plughw: as fallback if hw: fails. */ devices_with_spk[n++] = ucm_speaker_pcm; devices_with_spk[n++] = ucm_speaker_plug; for (int i = 0; devices_default[i] && n < 15; i++) devices_with_spk[n++] = devices_default[i]; devices_with_spk[n] = NULL; devices = devices_with_spk; } int err = -1; int card_idx = 0;
// AC_AUDIO_DEVICE override — try the env var device before the hardcoded list. const char *env_dev = getenv("AC_AUDIO_DEVICE"); if (env_dev && env_dev[0]) { err = snd_pcm_open(&pcm, env_dev, SND_PCM_STREAM_PLAYBACK, 0); if (err >= 0) { fprintf(stderr, "[audio] Opened AC_AUDIO_DEVICE=%s\n", env_dev); snprintf(audio->audio_device, sizeof(audio->audio_device), "%s", env_dev); if (sscanf(env_dev, "hw:%d", &card_idx) != 1 && sscanf(env_dev, "plughw:%d", &card_idx) != 1) card_idx = 0; } else { fprintf(stderr, "[audio] AC_AUDIO_DEVICE=%s failed: %s — falling back\n", env_dev, snd_strerror(err)); } }
for (int attempt = 0; attempt < 5 && err < 0; attempt++) { if (attempt > 0) { fprintf(alog, "[audio] Retry %d/4 — waiting 2s for codec probe...\n", attempt); fprintf(stderr, "[audio] Retry %d/4 — waiting 2s for codec probe...\n", attempt); usleep(2000000); // 2 seconds between retries } for (int i = 0; devices[i]; i++) { audio->audio_init_retries++; err = snd_pcm_open(&pcm, devices[i], SND_PCM_STREAM_PLAYBACK, 0); if (err >= 0) { fprintf(alog, "[audio] Opened ALSA device: %s (attempt %d)\n", devices[i], attempt); fprintf(stderr, "[audio] Opened ALSA device: %s (attempt %d)\n", devices[i], attempt); snprintf(audio->audio_device, sizeof(audio->audio_device), "%s", devices[i]); if (sscanf(devices[i], "hw:%d", &card_idx) != 1 && sscanf(devices[i], "plughw:%d", &card_idx) != 1) card_idx = 0; break; } if (attempt == 0) fprintf(alog, "[audio] Failed %s: %s\n", devices[i], snd_strerror(err)); } } audio->card_index = card_idx; if (alog != stderr) { fflush(alog); fclose(alog); } if (err < 0) { fprintf(stderr, "[audio] Cannot open any ALSA device after 5 attempts\n"); snprintf(audio->audio_status, sizeof(audio->audio_status), "no ALSA device found"); // Audio is optional — return the struct but with no PCM audio->pcm = NULL; return audio; }
// SOF detection must happen FIRST, because the format choice depends on it. // The S32_LE write path uses `<< 8` shift (writes int16 into the low 24 // bits of int32), which is correct for SOF's MAX98360A 24-bit DSP but // 256× too quiet for HDA's true 32-bit DAC — even though both codecs // accept S32_LE in their hw_params. Force S16_LE on non-SOF hardware. int sof_active = (access("/sys/module/snd_sof/initstate", F_OK) == 0) || (access("/sys/module/snd_sof_pci/initstate", F_OK) == 0);
// Configure ALSA — negotiate rate dynamically. // Try preferred rates from highest to lowest. The hardware decides what it // actually supports; we adapt period/buffer sizes to match the negotiated rate. snd_pcm_hw_params_t *params; snd_pcm_hw_params_alloca(¶ms); snd_pcm_hw_params_any(pcm, params); /* Prefer MMAP_INTERLEAVED: snd_pcm_mmap_writei skips the kernel * ring-buffer copy that snd_pcm_writei does, saving a fraction * of a millisecond on HDA paths. Fall back to RW_INTERLEAVED if * the hardware/driver doesn't expose mmap (rare on real PCMs; * common on plughw with rate conversion). */ audio->use_mmap = 0; if (snd_pcm_hw_params_set_access(pcm, params, SND_PCM_ACCESS_MMAP_INTERLEAVED) == 0) { audio->use_mmap = 1; fprintf(stderr, "[audio] Negotiated MMAP_INTERLEAVED access\n"); } else { snd_pcm_hw_params_any(pcm, params); snd_pcm_hw_params_set_access(pcm, params, SND_PCM_ACCESS_RW_INTERLEAVED); fprintf(stderr, "[audio] Negotiated RW_INTERLEAVED access (no mmap)\n"); } /* SOF topology FE PCMs use S32_LE internally; the SSP1 BE DAI * (MAX98360A) runs S24_LE. Writing S16_LE to this pipeline * causes 48dB attenuation + quantization noise ("crunchy quiet"). * Try S32_LE on SOF only. On HDA / USB / generic codecs, S16_LE * is the universally-correct choice — even when the codec * advertises S32_LE support, our int16<<8 conversion drops 8 of * the high bits and produces inaudibly-quiet output. */ audio->use_s32 = 0; if (sof_active && snd_pcm_hw_params_set_format(pcm, params, SND_PCM_FORMAT_S32_LE) == 0) { audio->use_s32 = 1; fprintf(stderr, "[audio] Negotiated S32_LE format (SOF)\n"); } else { /* Re-negotiate from scratch with S16_LE; preserve the access * mode we picked above. */ snd_pcm_hw_params_any(pcm, params); snd_pcm_hw_params_set_access(pcm, params, audio->use_mmap ? SND_PCM_ACCESS_MMAP_INTERLEAVED : SND_PCM_ACCESS_RW_INTERLEAVED); snd_pcm_hw_params_set_format(pcm, params, SND_PCM_FORMAT_S16_LE); fprintf(stderr, "[audio] Negotiated S16_LE format%s\n", sof_active ? " (S32_LE rejected)" : " (non-SOF, forced)"); } snd_pcm_hw_params_set_channels(pcm, params, AUDIO_CHANNELS);
// Query hardware rate range unsigned int rate_min = 0, rate_max = 0; snd_pcm_hw_params_get_rate_min(params, &rate_min, NULL); snd_pcm_hw_params_get_rate_max(params, &rate_max, NULL); fprintf(stderr, "[audio] Hardware rate range: %u–%u Hz\n", rate_min, rate_max);
// Pick sample rate: 48kHz is the safe default that all hardware can sustain. // Many codecs (e.g. Cirrus Logic CS4206) claim 192kHz support but can't // sustain it without constant XRUNs. Only use high rates on known-good // hardware (ThinkPad HDA with Realtek codec handles 192kHz fine). // Heuristic: if max rate > 48kHz AND min rate <= 32kHz, the codec is // likely a laptop HDA that works better at 48kHz. unsigned int rate = 48000; if (rate_max >= 192000 && rate_min > 44100) { // Dedicated audio interface — likely supports high rates reliably rate = 192000; } else if (rate_max >= 96000 && rate_min > 44100) { rate = 96000; } // Override: environment variable AC_AUDIO_RATE forces a specific rate const char *env_rate = getenv("AC_AUDIO_RATE"); if (env_rate) { unsigned int r = (unsigned int)atoi(env_rate); if (r >= rate_min && r <= rate_max) rate = r; } fprintf(stderr, "[audio] Selected rate: %u Hz (hw range %u–%u)\n", rate, rate_min, rate_max); snd_pcm_hw_params_set_rate_near(pcm, params, &rate, 0);
// Period + buffer sizing. The old config aimed for ~1ms latency (period = // rate/1000, buffer = 4 periods) which works on HDA-direct codecs but // breaks SOF+MAX98360A on Jasper Lake Chromebooks: the MAX98357A DAPM // event handler toggles the amp's SD_MODE GPIO on every PMU/PMD event, // and with a 4ms buffer the stream underruns constantly → DAPM rapid- // cycles the amp on/off → audio never stabilizes → speakers stay silent // despite mixer, codec, and GPIO all looking correct. We saw 10,686 // sdmode toggles in a single boot's kmsg on the G7 at the 1ms setting. // // Period + buffer: 20ms/80ms on SOF (avoids MAX98357A SD_MODE GPIO // thrash), 1ms/4ms on HDA-direct paths (tight latency safe there). // sof_active was set above before format negotiation. snd_pcm_uframes_t period; snd_pcm_uframes_t buffer_size; if (sof_active) { period = rate / 50; // 20ms (960 frames at 48kHz) buffer_size = period * 4; // 80ms total — larger buffer // reduces XRUN-induced "fuzzy" // audio at high software gain. // Previous 10ms/40ms produced // 96/480-frame short writes. fprintf(stderr, "[audio] SOF platform detected — period=%lu buffer=%lu (20ms/80ms)\n", (unsigned long)period, (unsigned long)buffer_size); } else { period = rate / 1000; // 1ms on HDA-direct paths if (period < 64) period = 64; buffer_size = period * 4; } snd_pcm_hw_params_set_period_size_near(pcm, params, &period, 0); snd_pcm_hw_params_set_buffer_size_near(pcm, params, &buffer_size);
err = snd_pcm_hw_params(pcm, params); if (err < 0) { fprintf(stderr, "[audio] Cannot configure ALSA at %uHz: %s\n", rate, snd_strerror(err)); // Last resort: try plughw with default params fprintf(stderr, "[audio] Trying plughw fallback...\n"); snd_pcm_close(pcm); err = snd_pcm_open(&pcm, "plughw:0,0", SND_PCM_STREAM_PLAYBACK, 0); if (err >= 0) { audio->use_mmap = 0; // plughw rate-conv path: no mmap snd_pcm_hw_params_any(pcm, params); snd_pcm_hw_params_set_access(pcm, params, SND_PCM_ACCESS_RW_INTERLEAVED); snd_pcm_hw_params_set_format(pcm, params, SND_PCM_FORMAT_S16_LE); snd_pcm_hw_params_set_channels(pcm, params, AUDIO_CHANNELS); rate = 48000; snd_pcm_hw_params_set_rate_near(pcm, params, &rate, 0); period = 256; snd_pcm_hw_params_set_period_size_near(pcm, params, &period, 0); buffer_size = 1024; snd_pcm_hw_params_set_buffer_size_near(pcm, params, &buffer_size); err = snd_pcm_hw_params(pcm, params); } if (err < 0) { fprintf(stderr, "[audio] All ALSA config attempts failed: %s\n", snd_strerror(err)); snd_pcm_close(pcm); audio->pcm = NULL; return audio; } snprintf(audio->audio_device, sizeof(audio->audio_device), "plughw:0,0"); }
snd_pcm_prepare(pcm); audio->pcm = pcm; audio->actual_rate = rate; audio->actual_period = (unsigned int)period;
/* Open the *other* PCM for jack-sense auto-routing. * * On sof-rt5682+max98360a, the SOF topology exposes two FE PCMs: * PCM 0 (UCM "Headphone") → SSP0 → RT5682 codec → headphone jack * PCM 1 (UCM "Speaker" ) → SSP1 → MAX98360A → speaker amp * * Each PCM goes to a *different* DAI, and the codec's DAPM jack-sense * mutes whichever side isn't currently in use. So if we open BOTH and * tee the same audio to both, the hardware automatically picks the * right output: speakers when no jack is plugged, headphones when one * is plugged. No userspace jack monitor needed. * * Only fires when the secondary PCM is a different device than the one * we already opened — duplicate-open of the same hw: device would just * fail with -EBUSY. */ audio->headphone_pcm = NULL; { const char *secondary = NULL; /* Opt-in: opening the headphone PCM at boot was powering up * the HP DAPM path even with UCM Headphones disabled, which * overrode jack-sense and silenced the MAX98360A amp. Keep * the secondary PCM closed by default; a future jack-watcher * thread will open/close it in response to plug events. Set * AC_AUDIO_TEE=1 to force-open anyway (for ThinkPad etc. * single-PCM HDA hardware, where it's a noop). */ const char *tee_env = getenv("AC_AUDIO_TEE"); int tee_enabled = (tee_env && tee_env[0] == '1'); if (tee_enabled && ucm_speaker_pcm[0] && ucm_headphone_pcm[0] && strcmp(ucm_speaker_pcm, ucm_headphone_pcm) != 0) { /* Pick whichever the main PCM didn't open. */ if (strstr(audio->audio_device, ucm_speaker_pcm)) secondary = ucm_headphone_pcm; else if (strstr(audio->audio_device, ucm_headphone_pcm)) secondary = ucm_speaker_pcm; else secondary = ucm_headphone_pcm; /* legacy fallback opened */ } if (secondary) { snd_pcm_t *pcm2 = NULL; int e2 = snd_pcm_open(&pcm2, secondary, SND_PCM_STREAM_PLAYBACK, 0); if (e2 == 0) { /* Same params as the main PCM so audio thread can write * the same int16 buffer to both without resampling. */ snd_pcm_hw_params_t *hp; snd_pcm_hw_params_alloca(&hp); snd_pcm_hw_params_any(pcm2, hp); snd_pcm_hw_params_set_access(pcm2, hp, SND_PCM_ACCESS_RW_INTERLEAVED); snd_pcm_hw_params_set_format(pcm2, hp, SND_PCM_FORMAT_S16_LE); snd_pcm_hw_params_set_channels(pcm2, hp, AUDIO_CHANNELS); unsigned int r2 = audio->actual_rate; snd_pcm_hw_params_set_rate_near(pcm2, hp, &r2, 0); snd_pcm_uframes_t p2 = audio->actual_period; snd_pcm_hw_params_set_period_size_near(pcm2, hp, &p2, 0); snd_pcm_uframes_t b2 = audio->actual_period * 4; snd_pcm_hw_params_set_buffer_size_near(pcm2, hp, &b2); int herr = snd_pcm_hw_params(pcm2, hp); if (herr == 0) { snd_pcm_prepare(pcm2); audio->headphone_pcm = pcm2; fprintf(stderr, "[audio] Parallel PCM opened: %s (%uHz, %lufrm) — auto-routing enabled\n", secondary, r2, (unsigned long)p2); } else { fprintf(stderr, "[audio] Parallel PCM hw_params failed for %s: %s — auto-routing disabled\n", secondary, snd_strerror(herr)); snd_pcm_close(pcm2); } } else { fprintf(stderr, "[audio] Parallel PCM open failed for %s: %s — auto-routing disabled\n", secondary, snd_strerror(e2)); } } }
// Update glitch rate for actual sample rate audio->glitch_rate = rate / 1600;
// Recent output history targets ~48k mono regardless of playback rate. unsigned int hist_target = rate > AUDIO_OUTPUT_HISTORY_RATE ? AUDIO_OUTPUT_HISTORY_RATE : rate; unsigned int hist_stride = rate > hist_target ? (rate + hist_target / 2) / hist_target : 1; if (hist_stride == 0) hist_stride = 1; audio->output_history_rate = rate / hist_stride; if (audio->output_history_rate == 0) audio->output_history_rate = rate; audio->output_history_downsample_n = hist_stride; audio->output_history_downsample_pos = 0; audio->output_history_size = (int)(audio->output_history_rate * AUDIO_OUTPUT_HISTORY_SECS); if (audio->output_history_size <= 0) { audio->output_history_size = AUDIO_OUTPUT_HISTORY_RATE * AUDIO_OUTPUT_HISTORY_SECS; audio->output_history_rate = AUDIO_OUTPUT_HISTORY_RATE; audio->output_history_downsample_n = 1; }
// Reallocate room buffers for actual rate int actual_room_size = (int)(0.12 * rate) * 3; if (actual_room_size != audio->room_size) { free(audio->room_buf_l); free(audio->room_buf_r); audio->room_size = actual_room_size; audio->room_buf_l = calloc(actual_room_size, sizeof(float)); audio->room_buf_r = calloc(actual_room_size, sizeof(float)); audio->room_pos = 0; }
/* Log the actual negotiated params — channels and format are * particularly important for diagnosing the "crunchy quiet" bug * on SOF boards where SSP1 may expect different bit depth. */ { snd_pcm_format_t fmt; unsigned int ch = 0; snd_pcm_hw_params_get_format(params, &fmt); snd_pcm_hw_params_get_channels(params, &ch); fprintf(stderr, "[audio] ALSA: %uHz %uch fmt=%s period=%lu buf=%lu (%.1fms)\n", rate, ch, snd_pcm_format_name(fmt), (unsigned long)period, (unsigned long)buffer_size, (double)period / rate * 1000.0); } snprintf(audio->audio_status, sizeof(audio->audio_status), "ok %uHz %lufrm", rate, (unsigned long)period); if (rate != AUDIO_SAMPLE_RATE) fprintf(stderr, "[audio] WARNING: got %uHz instead of %dHz\n", rate, AUDIO_SAMPLE_RATE);
// ChromeOS UCM verb activation. sof-rt5682 on Jasper Lake has no // upstream UCM, so without this the Speaker verb's csets // ('Spk Switch on' plus DSP pipeline routes) never fire and the // MAX98360A amp receives no I2S even with SD_MODE asserted. The // WeirdTreeThing/alsa-ucm-conf-cros bundle in /usr/share/alsa/ucm2/ // provides the downstream ChromeOS versions. Noop on boards whose // UCM is already upstream (ThinkPad HDA, Macs) — snd_use_case_mgr_open // returns -ENOENT and we fall through to the manual mixer path below. { char card_id[32] = ""; char id_path[64]; snprintf(id_path, sizeof(id_path), "/proc/asound/card%d/id", card_idx); FILE *idfp = fopen(id_path, "r"); if (idfp) { if (fgets(card_id, sizeof(card_id), idfp)) { char *nl = strchr(card_id, '\n'); if (nl) *nl = 0; } fclose(idfp); } if (card_id[0]) { /* The kernel strips hyphens from card IDs (so our machine * driver name `jsl_rt5682_def` + topology `sof-rt5682` both * become card id `sofrt5682`). The ChromeOS UCM tree keeps * the canonical hyphenated names. Try a few permutations so * whichever matches wins. */ const char *candidates[] = { card_id, /* e.g. "sofrt5682" */ "sof-rt5682", "sof-cs42l42", "sof-nau8825", "sof-da7219", NULL }; snd_use_case_mgr_t *uc = NULL; int uerr = -1; const char *opened = NULL; for (int i = 0; candidates[i]; i++) { uerr = snd_use_case_mgr_open(&uc, candidates[i]); if (uerr == 0) { opened = candidates[i]; break; } } if (uerr == 0) { fprintf(stderr, "[audio] UCM: opened '%s' (card=%s)\n", opened, card_id); if (snd_use_case_set(uc, "_verb", "HiFi") == 0) { fprintf(stderr, "[audio] UCM: _verb=HiFi set\n"); } else { fprintf(stderr, "[audio] UCM: _verb=HiFi failed\n"); } /* Enable ONLY Speaker at boot — enumerating every device * (including Headphones/Headset) was running ChromeOS * UCM EnableSequences that set `Headphone Jack Switch on` * + `HPOL/HPOR Playback Switch 1`. That forces DAPM to * route audio through the RT5682 headphone path and * powers down the MAX98360A amp (kmsg showed `sdmode * to 0` at 35s and never recovering). * * The rt5682-init BootSequence from WeirdTreeThing's * UCM deliberately ships with HP jack/switch OFF so * the speaker amp stays live when nothing is plugged * in. Keep that intact — only run the Speaker (and * mic) EnableSequence, not any headphone one. Jack- * plug routing becomes a later follow-up (a jack- * state watcher thread that flips _enadev on plug). */ const char **devlist = NULL; int ndev = snd_use_case_get_list(uc, "_devices/HiFi", &devlist); int enabled_speaker = 0; if (ndev > 0 && devlist) { for (int i = 0; i < ndev; i += 2) { const char *dev = devlist[i]; if (!dev || !dev[0]) continue; /* Skip anything that would re-enable the * headphone path at boot. Speakers first, * mics/HDMI are safe (no DAPM routing to HP). */ if (strstr(dev, "Headphone") || strstr(dev, "Headset") || strstr(dev, "Headphones")) { fprintf(stderr, "[audio] UCM: skip _enadev=%s (jack-gated)\n", dev); continue; } int rr = snd_use_case_set(uc, "_enadev", dev); fprintf(stderr, "[audio] UCM: _enadev=%s %s\n", dev, rr == 0 ? "ok" : "FAIL"); if (rr == 0 && (strstr(dev, "Speaker") || strstr(dev, "Speakers"))) enabled_speaker = 1; } snd_use_case_free_list(devlist, ndev); } else { /* Fallback: enable Speaker variants only. */ const char *names[] = {"Speaker", "Speakers", NULL}; for (int i = 0; names[i]; i++) { if (snd_use_case_set(uc, "_enadev", names[i]) == 0) { fprintf(stderr, "[audio] UCM: _enadev=%s ok\n", names[i]); enabled_speaker = 1; } } } if (!enabled_speaker) fprintf(stderr, "[audio] UCM: WARNING no Speaker device enabled\n"); snd_use_case_mgr_close(uc); } else { fprintf(stderr, "[audio] UCM: no config matched card '%s' — manual mixer fallback\n", card_id); } }
/* Defensive audio diagnostic — dump the full ASoC DAPM graph and * every kcontrol's current value so post-mortem log analysis can * tell whether a PGA is sitting at -inf, a DAPM widget is stuck * OFF, or a DAI isn't active. These files are debugfs-backed so * require CONFIG_DEBUG_FS=y and debugfs mounted at * /sys/kernel/debug (init already does the mount). Non-fatal if * absent. */ { const char *dbg_dir = "/sys/kernel/debug/asoc/card0"; if (access(dbg_dir, R_OK) == 0) { fprintf(stderr, "[audio-diag] ASoC debugfs dump — %s\n", dbg_dir); /* dapm/ subdir has one file per widget with its power state, * input/output connections, and active stream info. */ DIR *dapm = opendir("/sys/kernel/debug/asoc/card0/dapm"); if (dapm) { struct dirent *de; while ((de = readdir(dapm))) { if (de->d_name[0] == '.') continue; char widget_path[256]; snprintf(widget_path, sizeof(widget_path), "/sys/kernel/debug/asoc/card0/dapm/%s", de->d_name); FILE *wf = fopen(widget_path, "r"); if (!wf) continue; /* Each widget file's first line is the state: * "WidgetName: On in 0 out 0 stream ..." */ char wline[256]; if (fgets(wline, sizeof(wline), wf)) { char *nl = strchr(wline, '\n'); if (nl) *nl = 0; fprintf(stderr, "[audio-diag] dapm: %s\n", wline); } fclose(wf); } closedir(dapm); } /* /sys/kernel/debug/gpio dump shows MAX98360A SD_MODE + * RT5682 IRQ GPIO current state so we can tell if the * amp was powered at snapshot time. */ FILE *gf = fopen("/sys/kernel/debug/gpio", "r"); if (gf) { char gline[256]; int lines = 0; while (lines < 30 && fgets(gline, sizeof(gline), gf)) { char *nl = strchr(gline, '\n'); if (nl) *nl = 0; if (strstr(gline, "sdmode") || strstr(gline, "RT58") || strstr(gline, "gpiochip")) { fprintf(stderr, "[audio-diag] gpio: %s\n", gline); lines++; } } fclose(gf); } } else { fprintf(stderr, "[audio-diag] debugfs not mounted — no ASoC state available\n"); } } }
// Unmute ALL outputs (HDA Intel codecs have many controls that can mute) char mixer_card[16]; snprintf(mixer_card, sizeof(mixer_card), "hw:%d", card_idx); fprintf(stderr, "[audio] Using mixer: %s\n", mixer_card);
snd_mixer_t *mixer = NULL; if (snd_mixer_open(&mixer, 0) >= 0) { snd_mixer_attach(mixer, mixer_card); snd_mixer_selem_register(mixer, NULL, NULL); snd_mixer_load(mixer);
snd_mixer_elem_t *elem; for (elem = snd_mixer_first_elem(mixer); elem; elem = snd_mixer_elem_next(elem)) { const char *name = snd_mixer_selem_get_name(elem); if (!snd_mixer_selem_is_active(elem)) continue;
// Log all mixer elements — with pre-set values so a silent audio // log can be diagnosed without flashing again. If a playback- // switch element is already off before our unmute, or a volume // element reports a suspicious range (e.g. min==max at 0), we // want to know which one. fprintf(stderr, "[audio] Mixer: %s", name); if (snd_mixer_selem_has_playback_volume(elem)) { long vmin = 0, vmax = 0, vcur = 0; snd_mixer_selem_get_playback_volume_range(elem, &vmin, &vmax); snd_mixer_selem_get_playback_volume(elem, SND_MIXER_SCHN_FRONT_LEFT, &vcur); fprintf(stderr, " [vol %ld..%ld now=%ld]", vmin, vmax, vcur); long dbmin = 0, dbmax = 0, dbcur = 0; if (snd_mixer_selem_get_playback_dB_range(elem, &dbmin, &dbmax) == 0 && snd_mixer_selem_get_playback_dB(elem, SND_MIXER_SCHN_FRONT_LEFT, &dbcur) == 0) { fprintf(stderr, " [dB %.1f..%.1f now=%.1f]", dbmin / 100.0, dbmax / 100.0, dbcur / 100.0); } } if (snd_mixer_selem_has_playback_switch(elem)) { int sw = 0; snd_mixer_selem_get_playback_switch(elem, SND_MIXER_SCHN_FRONT_LEFT, &sw); fprintf(stderr, " [sw now=%s]", sw ? "on" : "OFF"); } if (snd_mixer_selem_has_capture_switch(elem)) fprintf(stderr, " [cap-sw]"); if (snd_mixer_selem_has_capture_volume(elem)) fprintf(stderr, " [cap-vol]"); fprintf(stderr, "\n");
// Unmute every playback switch we find — except the ones // the UCM BootSequence explicitly turns off to keep audio // routed to the speaker amp on unplugged-headphone state. // Flipping "Headphone Jack Switch" on re-enables the HP // DAPM path and silences MAX98360A even when nothing is // plugged in (see G7/Drawcia debug session). if (snd_mixer_selem_has_playback_switch(elem)) { int skip = 0; const char *jack_gated[] = { "Headphone Jack", /* rt5682 */ "Headphone Jack Switch", "HPOL Playback", "HPOR Playback", "Headset", NULL }; for (int j = 0; jack_gated[j]; j++) { if (strstr(name, jack_gated[j])) { skip = 1; break; } } if (!skip) { snd_mixer_selem_set_playback_switch_all(elem, 1); fprintf(stderr, "[audio] Unmuted: %s\n", name); } else { fprintf(stderr, "[audio] Skip unmute (jack-gated): %s\n", name); } }
// Set volume to max for output controls if (snd_mixer_selem_has_playback_volume(elem)) { long min, max; snd_mixer_selem_get_playback_volume_range(elem, &min, &max); snd_mixer_selem_set_playback_volume_all(elem, max); fprintf(stderr, "[audio] Volume %s: %ld/%ld\n", name, max, max); }
// NOTE: Do NOT touch capture mixer controls here — on the 11e Yoga // Gen 5, enabling capture switches at boot (before any capture PCM // is open) puts the HDA codec into a bad state that causes EIO when // the capture stream is later opened with period/buffer params. } snd_mixer_close(mixer); } else { fprintf(stderr, "[audio] Cannot open mixer\n"); }
// Read initial system volume. On SOF cards there's no Master mixer // and read_system_volume_card returns -1 — default to 150% (2.25× // linear) which is loud enough on tiny Chromebook speakers without // pushing soft_clip into audible distortion. Volume keys still go // up to 400% for very quiet hardware. int hw_vol = read_system_volume_card(card_idx); audio->system_volume = (hw_vol >= 0) ? hw_vol : 180; fprintf(stderr, "[audio] System volume: %d%% (hw=%d)\n", audio->system_volume, hw_vol);
// HDMI audio disabled — opening HDMI PCM streams on the same HDA controller // can exhaust controller streams and cause EIO on capture. audio->hdmi_pcm = NULL; fprintf(stderr, "[audio] HDMI audio: disabled\n");
// Start audio thread audio->running = 1; pthread_create(&audio->thread, NULL, audio_thread_fn, audio);
/* Force PCI runtime-PM to "on" for the sound card now that the * driver is loaded and card_idx is known. The init-script attempt * may fire before probe — doing it here guarantees the sysfs node * exists. Without this the SOF DSP auto-suspends after ~20-40s * of silence, which stops the SSP1 BE DAI and drops MAX98360A * sdmode to 0 (speaker amp off), and the amp never comes back. * Also try the generic PCI "power_save" disable for HDA paths. */ { char pm_path[128]; snprintf(pm_path, sizeof(pm_path), "/sys/class/sound/card%d/device/power/control", card_idx); FILE *pm = fopen(pm_path, "w"); if (pm) { fputs("on", pm); fclose(pm); fprintf(stderr, "[audio] Disabled runtime-PM: %s\n", pm_path); } else { fprintf(stderr, "[audio] Could not set runtime-PM: %s\n", pm_path); } /* Also try the autosuspend delay — set to -1 (never) */ snprintf(pm_path, sizeof(pm_path), "/sys/class/sound/card%d/device/power/autosuspend_delay_ms", card_idx); pm = fopen(pm_path, "w"); if (pm) { fputs("-1", pm); fclose(pm); fprintf(stderr, "[audio] Set autosuspend_delay=-1: %s\n", pm_path); } }
fprintf(stderr, "[audio] Ready\n"); return audio;}
uint64_t audio_synth(ACAudio *audio, WaveType type, double freq, double duration, double volume, double attack, double decay, double pan) { if (!audio) return 0;
pthread_mutex_lock(&audio->lock);
// Find free voice slot int slot = -1; for (int i = 0; i < AUDIO_MAX_VOICES; i++) { if (audio->voices[i].state == VOICE_INACTIVE) { slot = i; break; } } if (slot < 0) { // Steal oldest voice double oldest = 0; slot = 0; for (int i = 0; i < AUDIO_MAX_VOICES; i++) { if (audio->voices[i].elapsed > oldest) { oldest = audio->voices[i].elapsed; slot = i; } } }
ACVoice *v = &audio->voices[slot]; memset(v, 0, sizeof(ACVoice)); v->state = VOICE_ACTIVE; v->type = type; v->phase = 0.0; v->frequency = freq; v->target_frequency = freq; v->volume = volume; v->pan = pan; v->attack = attack > 0 ? attack : 0.005; v->decay = decay > 0 ? decay : 0.1; v->duration = duration; v->id = ++audio->next_id; v->started_at = audio->time;
if (type == WAVE_NOISE || type == WAVE_WHISTLE || type == WAVE_GUN || type == WAVE_HARP || type == WAVE_PIANO || type == WAVE_GMPIANO || type == WAVE_EPIANO || type == WAVE_PLUCK || type == WAVE_MODAL || type == WAVE_SYNTHBASS) { v->noise_seed = (uint32_t)(audio->next_id * 2654435761u); } if (type == WAVE_NOISE) { setup_noise_filter(v, (double)(audio->actual_rate ? audio->actual_rate : AUDIO_SAMPLE_RATE)); } else if (type == WAVE_GUN) { // Caller (audio_synth_gun) sets the preset via gun_init_voice // after this base init runs. } else if (type == WAVE_WHISTLE) { // Clear the waveguide state — bore + jet delay buffers and the // loop filter / DC blocker. Without this, leftover state from a // previous voice reuse would produce startup artifacts. memset(v->whistle_bore_buf, 0, sizeof(v->whistle_bore_buf)); memset(v->whistle_jet_buf, 0, sizeof(v->whistle_jet_buf)); v->whistle_bore_w = 0; v->whistle_jet_w = 0; v->whistle_breath = 0.0; v->whistle_vibrato_phase = 0.0; v->whistle_lp1 = 0.0; v->whistle_hp_x1 = 0.0; v->whistle_hp_y1 = 0.0; } else if (type == WAVE_HARP) { // Karplus-Strong pluck: seed the delay line with one wavelength // of pre-smoothed white noise. The initial noise IS the pluck — // attack is instantaneous, and the circulating filter+decay // shapes it into a plucked-string tone. // Karplus & Strong (1983), Computer Music Journal 7(2), 43-55. memset(v->whistle_bore_buf, 0, sizeof(v->whistle_bore_buf)); v->harp_lp1 = 0.0; double sr = (double)(audio->actual_rate ? audio->actual_rate : AUDIO_SAMPLE_RATE); double string_delay = sr / freq; const int STRING_N = 2048; if (string_delay > (double)(STRING_N - 2)) string_delay = (double)(STRING_N - 2); if (string_delay < 2.0) string_delay = 2.0; int n = (int)string_delay; // Pre-smooth the excitation so the initial transient is softer // (Jaffe-Smith "pick direction" / brightness control, simplified). double last = 0.0; for (int i = 0; i < n; i++) { double white = ((double)xorshift32(&v->noise_seed) / (double)UINT32_MAX) * 2.0 - 1.0; double filt = 0.5 * (white + last); last = white; v->whistle_bore_buf[i] = (float)filt; } // Next write lands past the pluck; first read pulls buf[0]. v->whistle_bore_w = n; } else if (type == WAVE_PIANO) { // Sample-bank piano. Find the nearest anchor in piano_bank by // MIDI distance, set step = 2^((target_midi - anchor_midi)/12) // for pitch shift, position = 0 to start playback from the // hammer attack. If no bank loaded (samples missing on the // initramfs), the voice produces silence — non-fatal. double f0 = freq < 20.0 ? 20.0 : freq; // Convert frequency to MIDI: midi = 69 + 12*log2(f / 440). double target_midi_d = 69.0 + 12.0 * log2(f0 / 440.0); int target_midi = (int)(target_midi_d + 0.5);
const PianoSample *anchor = pick_piano_anchor(target_midi); if (anchor && anchor->data && anchor->len > 0) { v->piano_sample_data = anchor->data; v->piano_sample_len = anchor->len; v->piano_sample_pos = 0.0; // step = 2^((target - anchor)/12). Positive offset → faster // playback → higher pitch. Sample is at AUDIO_SAMPLE_RATE // already (decimated at build time), so no sample-rate // correction is needed beyond the pitch ratio. double semis = target_midi_d - (double)anchor->midi; v->piano_sample_step = pow(2.0, semis / 12.0); // Salamander samples sit several dB below the ±1 oscillators // (recorded with headroom across velocity layers), so a bare // pass-through reads quieter than sine/square at the same // notepat `volume`. 3.0× brings perceived loudness in line // with the basic waves; soft_clip absorbs any peak excess. v->piano_sample_amp = 3.0; ac_log("[piano] f0=%.1fHz midi=%d → anchor midi=%d step=%.4f len=%d\n", f0, target_midi, anchor->midi, v->piano_sample_step, anchor->len); } else { v->piano_sample_data = NULL; v->piano_sample_len = 0; v->piano_sample_pos = 0.0; v->piano_sample_step = 1.0; v->piano_sample_amp = 0.0; ac_log("[piano] no bank loaded — voice silent (target midi=%d)\n", target_midi); } }
pthread_mutex_unlock(&audio->lock); return v->id;}
// gm_program_implemented() now lives in the standalone gm_synth module// (gm_synth.h / gm_synth.c) — it is the same 0-based program-range table.
// GM synthesis voice (docs/gm-synthesis/). Mirrors audio_synth_gun: do the base// voice setup (slot alloc, envelope fields, per-trigger noise_seed) via// audio_synth with a GM placeholder type so the seed is set, then run// gm_voice_init() to fill the standalone GMVoice (ACVoice.gm) state + apply// note-on stochasticism. Unimplemented programs return 0 so the JS caller can// fall back to the normal `type`-based audio_synth path. v->type is kept as one// of the GM WaveTypes so the render switch routes here and the phase-advance// guard skips it; the *actual* engine is stored inside v->gm.engine and// gm_voice_render() dispatches on it. We map the chosen engine back onto// v->type for parity with the pre-extraction behavior (type checks elsewhere).uint64_t audio_synth_gm(ACAudio *audio, int program, double freq, double duration, double volume, double attack, double decay, double pan) { if (!audio) return 0; if (!gm_program_implemented(program)) return 0; uint64_t id = audio_synth(audio, WAVE_GMPIANO, freq, duration, volume, attack, decay, pan); if (!id) return 0;
pthread_mutex_lock(&audio->lock); ACVoice *v = NULL; for (int i = 0; i < AUDIO_MAX_VOICES; i++) { if (audio->voices[i].id == id) { v = &audio->voices[i]; break; } } int ok = 1; if (v) { double sr = (double)(audio->actual_rate ? audio->actual_rate : AUDIO_SAMPLE_RATE); if (gm_voice_init(&v->gm, program, freq, sr, v->noise_seed) < 0) { // gm_program_implemented() said yes but init disagreed — retire the // slot and report no-voice so the JS caller falls back cleanly. v->state = VOICE_INACTIVE; ok = 0; } else { // Reflect the chosen engine in v->type (render still routes all GM // types through gm_voice_render; this keeps type-based guards right). switch (v->gm.engine) { case GM_ENGINE_GMPIANO: v->type = WAVE_GMPIANO; break; case GM_ENGINE_EPIANO: v->type = WAVE_EPIANO; break; case GM_ENGINE_PLUCK: v->type = WAVE_PLUCK; break; case GM_ENGINE_MODAL: v->type = WAVE_MODAL; break; case GM_ENGINE_SYNTHBASS: v->type = WAVE_SYNTHBASS; break; default: break; // stays WAVE_GMPIANO } } } pthread_mutex_unlock(&audio->lock); return ok ? id : 0;}
void audio_kill(ACAudio *audio, uint64_t id, double fade) { if (!audio) return; pthread_mutex_lock(&audio->lock); for (int i = 0; i < AUDIO_MAX_VOICES; i++) { if (audio->voices[i].id == id && audio->voices[i].state == VOICE_ACTIVE) { audio->voices[i].state = VOICE_KILLING; audio->voices[i].fade_duration = fade > 0 ? fade : 0.025; audio->voices[i].fade_elapsed = 0.0; // Gun-specific release behaviors (e.g. ricochet pitch drop). if (audio->voices[i].type == WAVE_GUN) { gun_on_release(&audio->voices[i]); } break; } } pthread_mutex_unlock(&audio->lock);}
uint64_t audio_synth_gun(ACAudio *audio, GunPreset preset, double duration, double volume, double attack, double decay, double pan, double pressure_scale, int force_model) { if (!audio) return 0; // Delegate base voice setup (slot alloc, envelope fields, noise seed). // Frequency is unused for guns — the DWG cavity resonance comes from // the preset's bore_length, not v->frequency. We pass 110 to keep // the smoothing code happy. uint64_t id = audio_synth(audio, WAVE_GUN, 110.0, duration, volume, attack, decay, pan); if (!id) return 0;
pthread_mutex_lock(&audio->lock); ACVoice *v = NULL; for (int i = 0; i < AUDIO_MAX_VOICES; i++) { if (audio->voices[i].id == id) { v = &audio->voices[i]; break; } } if (v) { double sr = (double)(audio->actual_rate ? audio->actual_rate : AUDIO_SAMPLE_RATE); gun_init_voice(v, preset, sr, force_model); if (pressure_scale > 0.0 && pressure_scale != 1.0) { v->gun_pressure *= pressure_scale; } } pthread_mutex_unlock(&audio->lock); return id;}
// Apply a single per-shot param override to a freshly-initialized gun// voice. Called by the JS bindings between audio_synth_gun() and the// audio thread's first read of the voice — lets the inspector's// drag-to-edit cards push live tuning values into the next shot// without rebuilding gun_presets[]. Unknown keys are silently ignored.//// Layer-state fields (envelopes, biquad coefficients, the Friedlander// pulse position) are NOT exposed; we only change the constants the// preset would have set in init.void audio_gun_voice_set_param(ACAudio *audio, uint64_t id, const char *key, double value) { if (!audio || !key) return; pthread_mutex_lock(&audio->lock); ACVoice *v = NULL; for (int i = 0; i < AUDIO_MAX_VOICES; i++) { if (audio->voices[i].id == id && audio->voices[i].type == WAVE_GUN) { v = &audio->voices[i]; break; } } if (!v) { pthread_mutex_unlock(&audio->lock); return; }
double sr = (double)(audio->actual_rate ? audio->actual_rate : AUDIO_SAMPLE_RATE); if (v->gun_model == GUN_MODEL_CLASSIC) { if (strcmp(key, "click_amp") == 0) v->gun_click_amp = value; else if (strcmp(key, "click_decay_ms") == 0) { double tau = (value > 0.05 ? value : 0.05) * 0.001; v->gun_click_decay_mult = exp(-1.0 / (tau * sr)); } else if (strcmp(key, "crack_amp") == 0) v->gun_body_amp[0] = value; else if (strcmp(key, "crack_decay_ms") == 0) { double tau = (value > 0.1 ? value : 0.1) * 0.001; v->gun_env_decay_mult = exp(-1.0 / (tau * sr)); } else if (strcmp(key, "crack_fc") == 0 || strcmp(key, "crack_q") == 0) { // Both freq and Q feed the same biquad, recompute together. // For partial updates we just recompute with the latest value // and keep the other from existing coefs (lossy but adequate). // Approximate Q from a2 = r² → r = √a2 → tau = -π·f/(Q·sr·ln r). double a2 = v->gun_body_a2[0]; double r = a2 > 0 ? sqrt(a2) : 0.95; double cur_w = acos(v->gun_body_a1[0] / (2.0 * r)); double cur_f = cur_w * sr / (2.0 * M_PI); double cur_q = -M_PI * cur_f / (sr * log(r > 0.0001 ? r : 0.0001)); double f = (strcmp(key, "crack_fc") == 0) ? value : cur_f; double q = (strcmp(key, "crack_q") == 0) ? value : cur_q; compute_resonator(f, q, sr, &v->gun_body_a1[0], &v->gun_body_a2[0], &v->gun_crack_b0); } else if (strcmp(key, "boom_amp") == 0) v->gun_body_amp[1] = value; else if (strcmp(key, "boom_freq_start") == 0) { v->gun_boom_freq_start = value; v->gun_boom_freq = value; } else if (strcmp(key, "boom_freq_end") == 0) v->gun_boom_freq_end = value; else if (strcmp(key, "boom_pitch_decay_ms") == 0) { double tau = (value > 0.1 ? value : 0.1) * 0.001; v->gun_boom_pitch_mult = exp(-1.0 / (tau * sr)); } else if (strcmp(key, "boom_amp_decay_ms") == 0) { double tau = (value > 0.1 ? value : 0.1) * 0.001; v->gun_boom_decay_mult = exp(-1.0 / (tau * sr)); } else if (strcmp(key, "tail_amp") == 0) v->gun_body_amp[2] = value; else if (strcmp(key, "tail_decay_ms") == 0) { double tau = (value > 0.1 ? value : 0.1) * 0.001; v->gun_tail_decay_mult = exp(-1.0 / (tau * sr)); } else if (strcmp(key, "tail_fc") == 0 || strcmp(key, "tail_q") == 0) { double a2 = v->gun_body_a2[1]; double r = a2 > 0 ? sqrt(a2) : 0.95; double cur_w = acos(v->gun_body_a1[1] / (2.0 * r)); double cur_f = cur_w * sr / (2.0 * M_PI); double cur_q = -M_PI * cur_f / (sr * log(r > 0.0001 ? r : 0.0001)); double f = (strcmp(key, "tail_fc") == 0) ? value : cur_f; double q = (strcmp(key, "tail_q") == 0) ? value : cur_q; compute_resonator(f, q, sr, &v->gun_body_a1[1], &v->gun_body_a2[1], &v->gun_tail_b0); } } else { // Physical model overrides. if (strcmp(key, "pressure") == 0) v->gun_pressure = value; else if (strcmp(key, "env_rate") == 0) { v->gun_phys_t_plus = (3.0 / (value > 100 ? value : 100.0)) * sr; if (v->gun_phys_t_plus < 32.0) v->gun_phys_t_plus = 32.0; if (v->gun_phys_t_plus > 4096.0) v->gun_phys_t_plus = 4096.0; } else if (strcmp(key, "bore_length_s") == 0) { v->gun_bore_delay = value * sr; if (v->gun_bore_delay < 4.0) v->gun_bore_delay = 4.0; if (v->gun_bore_delay > 2040.0) v->gun_bore_delay = 2040.0; } else if (strcmp(key, "bore_loss") == 0) v->gun_bore_loss = value; else if (strcmp(key, "breech_reflect") == 0) v->gun_breech_reflect = value; else if (strcmp(key, "noise_gain") == 0) v->gun_noise_gain = value; else if (strcmp(key, "radiation") == 0) v->gun_radiation_a = value; else if (strncmp(key, "body_freq", 9) == 0 || strncmp(key, "body_q", 6) == 0) { int idx = key[strlen(key) - 1] - '0'; if (idx < 0 || idx > 2) { pthread_mutex_unlock(&audio->lock); return; } // Recompute the resonator with one swapped param, the other inferred. double a2 = v->gun_body_a2[idx]; double r = a2 > 0 ? sqrt(a2) : 0.95; double cur_w = acos(v->gun_body_a1[idx] / (2.0 * r)); double cur_f = cur_w * sr / (2.0 * M_PI); double cur_q = -M_PI * cur_f / (sr * log(r > 0.0001 ? r : 0.0001)); double f = (strncmp(key, "body_freq", 9) == 0) ? value : cur_f; double q = (strncmp(key, "body_q", 6) == 0) ? value : cur_q; double b0_unused; compute_resonator(f, q, sr, &v->gun_body_a1[idx], &v->gun_body_a2[idx], &b0_unused); } else if (strncmp(key, "body_amp", 8) == 0) { int idx = key[strlen(key) - 1] - '0'; if (idx >= 0 && idx <= 2) v->gun_body_amp[idx] = value; } } pthread_mutex_unlock(&audio->lock);}
void audio_update(ACAudio *audio, uint64_t id, double freq, double volume, double pan) { if (!audio) return; pthread_mutex_lock(&audio->lock); for (int i = 0; i < AUDIO_MAX_VOICES; i++) { if (audio->voices[i].id == id && audio->voices[i].state != VOICE_INACTIVE) { if (freq > 0) audio->voices[i].target_frequency = freq; if (volume >= 0) audio->voices[i].volume = volume; if (pan > -2.0) audio->voices[i].pan = pan; break; } } pthread_mutex_unlock(&audio->lock);}
int audio_beat_check(ACAudio *audio) { if (!audio) return 0; int triggered = audio->beat_triggered; if (triggered) audio->beat_triggered = 0; return triggered;}
void audio_set_bpm(ACAudio *audio, double bpm) { if (!audio || bpm <= 0) return; pthread_mutex_lock(&audio->lock); audio->bpm = bpm; pthread_mutex_unlock(&audio->lock);}
void audio_room_toggle(ACAudio *audio) { if (!audio) return; audio->room_enabled = !audio->room_enabled; fprintf(stderr, "[audio] Room: %s\n", audio->room_enabled ? "ON" : "OFF");}
void audio_glitch_toggle(ACAudio *audio) { if (!audio) return; if (audio->glitch_enabled || audio->target_glitch_mix > 0.001f || audio->glitch_mix > 0.001f) { audio->glitch_enabled = 0; audio->target_glitch_mix = 0.0f; } else { audio->glitch_enabled = 1; audio->target_glitch_mix = 1.0f; } fprintf(stderr, "[audio] Glitch: %s (mix %.2f)\n", audio->glitch_enabled ? "ON" : "OFF", audio->target_glitch_mix);}
void audio_set_room_mix(ACAudio *audio, float mix) { if (!audio) return; if (mix < 0.0f) mix = 0.0f; if (mix > 1.0f) mix = 1.0f; audio->target_room_mix = mix;}
void audio_set_glitch_mix(ACAudio *audio, float mix) { if (!audio) return; if (mix < 0.0f) mix = 0.0f; if (mix > 1.0f) mix = 1.0f; audio->target_glitch_mix = mix; audio->glitch_enabled = mix > 0.001f; if (!audio->glitch_enabled) audio->glitch_counter = 0;}
void audio_set_fx_mix(ACAudio *audio, float mix) { if (!audio) return; if (mix < 0.0f) mix = 0.0f; if (mix > 1.0f) mix = 1.0f; audio->target_fx_mix = mix;}
// User-exposed master gain. Range 0..2 (200%) — above that you're almost// certainly just hitting soft_clip and colouring the signal, so clamp// before that to avoid giving false "louder" feedback in the UI slider.void audio_set_master_volume(ACAudio *audio, float value) { if (!audio) return; if (value < 0.0f) value = 0.0f; if (value > 2.0f) value = 2.0f; audio->target_master_volume = value;}
void audio_set_mono(ACAudio *audio, int enabled) { if (!audio) return; audio->mono = enabled ? 1 : 0;}
// Drive amount 0..1 dry/wet blend. 0 = clean bypass, 1 = fully driven// (pre-gain × 6 into tanh, attenuated back). Smoothed per-sample so// sliding the fader doesn't audibly zipper.void audio_set_drive_mix(ACAudio *audio, float value) { if (!audio) return; if (value < 0.0f) value = 0.0f; if (value > 1.0f) value = 1.0f; audio->target_drive_mix = value;}
// Global GM-synthesis organic amount (docs/gm-synthesis/00-stochasticism.md).// Scales every parametric note-on jitter lever; 0 restores bit-identical// synthesis. `audio` is accepted for API symmetry but the value lives in a// file-static so the note-on helpers stay dependency-free in the inner code.void audio_set_organic(double amt) { gm_set_organic(clampd(amt, 0.0, 1.0));}
// Wobble / flange dry/wet 0..1. LFO-modulated short delay blended with// the dry signal. Same exponential smoother as the other mix params so// a fader sweep doesn't click. The LFO rate itself is fixed at 0.4 Hz// and doesn't need smoothing.void audio_set_wobble_mix(ACAudio *audio, float value) { if (!audio) return; if (value < 0.0f) value = 0.0f; if (value > 1.0f) value = 1.0f; audio->target_wobble_mix = value;}
// Pause/resume writes to output_history_buf. Called from notepat while// the spacebar is held for reverse-replay: with writes paused the reverse// playback echo (re-captured from the speaker mix) can't double-layer// over the original wave in the visualizer AND any overdub played during// the hold is purely monitored — not written into the capture ring.// Release un-pauses; writes pick back up exactly where they left off so// the buffer boundary is invisible to downstream consumers.void audio_set_output_history_paused(ACAudio *audio, int paused) { if (!audio) return; audio->output_history_paused = paused ? 1 : 0;}
// --- Hot-mic capture thread ---// Device opens once (on wave-enter), stays running. Always reads to keep// ALSA happy and the level meter live. Only writes to sample_buf when// recording flag is set. Instant recording with zero device-open latency.//// IMPORTANT: HDMI audio must be DISABLED in audio_init and playback buffer// must be 3 periods (not 6) — otherwise the HDA controller runs out of// streams and capture gets EIO.static void *capture_thread_func(void *arg) { ACAudio *audio = (ACAudio *)arg; snd_pcm_t *cap = NULL;
const char *devices[] = {"hw:0,0", "hw:1,0", "hw:0,6", "hw:0,7", "plughw:0,0", "plughw:1,0", "default", NULL}; for (int i = 0; devices[i]; i++) { if (snd_pcm_open(&cap, devices[i], SND_PCM_STREAM_CAPTURE, 0) == 0) { snprintf(audio->mic_device, sizeof(audio->mic_device), "%s", devices[i]); ac_log("[mic] opened capture device: %s\n", devices[i]); break; } cap = NULL; } if (!cap) { snprintf(audio->mic_last_error, sizeof(audio->mic_last_error), "no capture device found"); ac_log("[mic] no capture device found\n"); audio->mic_hot = 0; return NULL; }
// Enable capture mixer switches now that capture PCM is open. // (Safe to do after snd_pcm_open — avoids the pre-open EIO bug on some HDA.) { char mixer_card[16]; snprintf(mixer_card, sizeof(mixer_card), "hw:%d", audio->card_index); snd_mixer_t *cmix = NULL; if (snd_mixer_open(&cmix, 0) >= 0) { snd_mixer_attach(cmix, mixer_card); snd_mixer_selem_register(cmix, NULL, NULL); snd_mixer_load(cmix); snd_mixer_elem_t *el; for (el = snd_mixer_first_elem(cmix); el; el = snd_mixer_elem_next(el)) { if (!snd_mixer_selem_is_active(el)) continue; if (snd_mixer_selem_has_capture_switch(el)) { snd_mixer_selem_set_capture_switch_all(el, 1); ac_log("[mic] enabled capture switch: %s\n", snd_mixer_selem_get_name(el)); } if (snd_mixer_selem_has_capture_volume(el)) { long cmin, cmax; snd_mixer_selem_get_capture_volume_range(el, &cmin, &cmax); snd_mixer_selem_set_capture_volume_all(el, cmax); ac_log("[mic] capture volume %s: %ld/%ld\n", snd_mixer_selem_get_name(el), cmax, cmax); } } snd_mixer_close(cmix); } }
snd_pcm_hw_params_t *hw; snd_pcm_hw_params_alloca(&hw); snd_pcm_hw_params_any(cap, hw); snd_pcm_hw_params_set_access(cap, hw, SND_PCM_ACCESS_RW_INTERLEAVED); snd_pcm_hw_params_set_format(cap, hw, SND_PCM_FORMAT_S16_LE);
unsigned int channels = 1; if (snd_pcm_hw_params_set_channels(cap, hw, 1) < 0) { channels = 2; snd_pcm_hw_params_set_channels(cap, hw, 2); }
unsigned int rate = 48000; snd_pcm_hw_params_set_rate_near(cap, hw, &rate, NULL);
// Set period=1024 (~21ms) for low-latency capture. This previously // caused EIO but the root causes were: HDMI audio open (exhausting // HDA streams), 6-period playback buffer, and capture mixer in // audio_init. All three are now fixed. snd_pcm_uframes_t period_frames = 1024; snd_pcm_hw_params_set_period_size_near(cap, hw, &period_frames, NULL); snd_pcm_uframes_t buffer_frames = 8192; snd_pcm_hw_params_set_buffer_size_near(cap, hw, &buffer_frames);
if (snd_pcm_hw_params(cap, hw) < 0) { snprintf(audio->mic_last_error, sizeof(audio->mic_last_error), "failed to configure capture"); ac_log("[mic] failed to configure capture\n"); snd_pcm_close(cap); audio->mic_hot = 0; return NULL; }
// Enable capture mixer (safe here — after PCM open, in capture thread) { int cnum = 0; const char *d = audio->mic_device; while (*d && (*d < '0' || *d > '9')) d++; if (*d) cnum = atoi(d); char ccard[16]; snprintf(ccard, sizeof(ccard), "hw:%d", cnum); snd_mixer_t *cmix = NULL; if (snd_mixer_open(&cmix, 0) >= 0) { snd_mixer_attach(cmix, ccard); snd_mixer_selem_register(cmix, NULL, NULL); snd_mixer_load(cmix); snd_mixer_elem_t *elem; for (elem = snd_mixer_first_elem(cmix); elem; elem = snd_mixer_elem_next(elem)) { if (!snd_mixer_selem_is_active(elem)) continue; if (snd_mixer_selem_has_capture_switch(elem)) { snd_mixer_selem_set_capture_switch_all(elem, 1); ac_log("[mic] capture switch ON: %s\n", snd_mixer_selem_get_name(elem)); } if (snd_mixer_selem_has_capture_volume(elem)) { long cmin, cmax; snd_mixer_selem_get_capture_volume_range(elem, &cmin, &cmax); long cset = cmin + ((cmax - cmin) * 9) / 10; snd_mixer_selem_set_capture_volume_all(elem, cset); ac_log("[mic] capture volume %s: %ld/%ld\n", snd_mixer_selem_get_name(elem), cset, cmax); } } snd_mixer_close(cmix); } }
audio->sample_rate = rate; audio->mic_connected = 1; ac_log("[mic] hot-mic running at %u Hz, %u ch\n", rate, channels);
int16_t buf[1024 * 2]; while (audio->mic_hot) { int n = snd_pcm_readi(cap, buf, 512); if (n < 0) { n = snd_pcm_recover(cap, n, 0); if (n < 0) { snprintf(audio->mic_last_error, sizeof(audio->mic_last_error), "capture read failed: %s", snd_strerror(n)); ac_log("[mic] capture read failed: %s\n", snd_strerror(n)); break; } continue; }
float peak = 0.0f; // Aggressive compressor + hard limiter to prevent clipping. // Matches the note compression style in the synth output. static float env = 0.0f; // envelope follower static float comp_gain = 1.0f; // current gain const float threshold = 0.15f; // compress early (mic input is often hot) const float ratio = 12.0f; // aggressive compression const float attack = 0.005f; // fast attack const float release = 0.00005f; // slow release (smooth) const float limiter = 0.9f; // hard limiter ceiling
for (int s = 0; s < n; s++) { float sample; if (channels == 1) { sample = buf[s] / 32768.0f; } else { sample = (buf[s * 2] + buf[s * 2 + 1]) / 65536.0f; }
// Envelope follower float abs_s = fabsf(sample); if (abs_s > env) env += attack * (abs_s - env); else env += release * (abs_s - env);
// Compute gain reduction if (env > threshold) { float over = env - threshold; float reduced = threshold + over / ratio; comp_gain = reduced / env; } else { comp_gain += 0.0002f * (1.0f - comp_gain); }
sample *= comp_gain;
// Hard limiter — prevent any clipping if (sample > limiter) sample = limiter; else if (sample < -limiter) sample = -limiter;
if (abs_s > peak) peak = abs_s;
// Always write to ring buffer audio->mic_ring[audio->mic_ring_pos % audio->sample_max_len] = sample; audio->mic_ring_pos++;
// Direct-write when recording if (audio->recording && audio->sample_write_pos < audio->sample_max_len) { audio->sample_buf[audio->sample_write_pos++] = sample; } } // If we skipped the first chunk, mark that we've consumed it // by writing at least 0 (sample_write_pos stays 0, next chunk writes) audio->mic_level = peak;
if (audio->recording && audio->sample_write_pos >= audio->sample_max_len) { audio->sample_len = audio->sample_write_pos; audio->recording = 0; ac_log("[mic] recording buffer full (%d samples)\n", audio->sample_len); } }
ac_log("[mic] hot-mic thread exiting, device=%s\n", audio->mic_device); snd_pcm_close(cap); audio->mic_connected = 0; audio->recording = 0; return NULL;}
int audio_mic_open(ACAudio *audio) { if (!audio || audio->mic_hot || audio->capture_thread_running) return -1; audio->mic_hot = 1; audio->capture_thread_running = 1; audio->mic_last_error[0] = 0; ac_log("[mic] opening hot-mic\n"); if (pthread_create(&audio->capture_thread, NULL, capture_thread_func, audio) != 0) { audio->mic_hot = 0; audio->capture_thread_running = 0; ac_log("[mic] failed to create capture thread\n"); return -1; } return 0;}
void audio_mic_close(ACAudio *audio) { if (!audio) return; audio->recording = 0; audio->mic_hot = 0; if (audio->capture_thread_running) { pthread_join(audio->capture_thread, NULL); audio->capture_thread_running = 0; } ac_log("[mic] hot-mic closed\n");}
int audio_mic_start(ACAudio *audio) { if (!audio || audio->recording) return -1; if (!audio->mic_hot) { int rc = audio_mic_open(audio); if (rc != 0) return rc; } // Kill any playing sample voices for (int i = 0; i < AUDIO_MAX_SAMPLE_VOICES; i++) audio->sample_voices[i].active = 0; audio->rec_start_ring_pos = audio->mic_ring_pos; audio->sample_len = 0; audio->sample_write_pos = 0; __sync_synchronize(); audio->recording = 1; ac_log("[mic] recording started (instant), ring_pos=%d\n", audio->rec_start_ring_pos); return 0;}
int audio_mic_stop(ACAudio *audio) { if (!audio) return 0; audio->recording = 0; __sync_synchronize();
// Kill all sample voices BEFORE touching sample_buf — // playback thread reads sample_buf[]/sample_len without locks for (int i = 0; i < AUDIO_MAX_SAMPLE_VOICES; i++) audio->sample_voices[i].active = 0; __sync_synchronize();
int direct_len = audio->sample_write_pos; if (direct_len > 0) { audio->sample_len = direct_len; ac_log("[mic] recording stopped (direct), sample_len=%d sample_rate=%u\n", audio->sample_len, audio->sample_rate); } else { // Fallback: extract from ring buffer int start = audio->rec_start_ring_pos; int end = audio->mic_ring_pos; int len = end - start; if (len < 0) len = 0; if (len > audio->sample_max_len) len = audio->sample_max_len; for (int i = 0; i < len; i++) { audio->sample_buf[i] = audio->mic_ring[(start + i) % audio->sample_max_len]; } audio->sample_len = len; ac_log("[mic] recording stopped (ring), sample_len=%d ring_span=%d sample_rate=%u\n", audio->sample_len, end - start, audio->sample_rate); } // Auto-trim silence from start (threshold: ~0.01 = -40dB) if (audio->sample_len > 0) { const float trim_threshold = 0.01f; int trim_start = 0; while (trim_start < audio->sample_len && fabsf(audio->sample_buf[trim_start]) < trim_threshold) { trim_start++; } if (trim_start > 0 && trim_start < audio->sample_len) { int new_len = audio->sample_len - trim_start; memmove(audio->sample_buf, audio->sample_buf + trim_start, new_len * sizeof(float)); audio->sample_len = new_len; ac_log("[mic] auto-trimmed %d silent samples from start\n", trim_start); } }
return audio->sample_len;}
// --- Sample bank: get/load data for per-key samples ---int audio_sample_get_data(ACAudio *audio, float *out, int max_len) { if (!audio || !out || audio->sample_len == 0) return 0; int len = audio->sample_len < max_len ? audio->sample_len : max_len; memcpy(out, audio->sample_buf, len * sizeof(float)); return len;}
int audio_output_get_recent(ACAudio *audio, float *out, int max_len, unsigned int *out_rate) { if (!audio || !out || max_len <= 0 || !audio->output_history_buf || audio->output_history_size <= 0) { if (out_rate) *out_rate = 0; return 0; }
pthread_mutex_lock(&audio->lock); if (out_rate) *out_rate = audio->output_history_rate;
uint64_t write_pos = audio->output_history_write_pos; int available = write_pos < (uint64_t)audio->output_history_size ? (int)write_pos : audio->output_history_size; int len = available < max_len ? available : max_len; uint64_t start = write_pos - (uint64_t)len; for (int i = 0; i < len; i++) { out[i] = audio->output_history_buf[(start + (uint64_t)i) % (uint64_t)audio->output_history_size]; }
pthread_mutex_unlock(&audio->lock); return len;}
void audio_sample_load_data(ACAudio *audio, const float *data, int len, unsigned int rate) { if (!audio || !data || len <= 0 || !audio->sample_buf_back) return; if (len > audio->sample_max_len) len = audio->sample_max_len; // Write to back buffer (only JS thread writes here — safe without lock) memcpy(audio->sample_buf_back, data, len * sizeof(float)); if (len < audio->sample_max_len) memset(audio->sample_buf_back + len, 0, (audio->sample_max_len - len) * sizeof(float)); // Swap pointers under lock — audio callback checks sample_loading flag pthread_mutex_lock(&audio->lock); float *tmp = audio->sample_buf; audio->sample_buf = audio->sample_buf_back; audio->sample_buf_back = tmp; audio->sample_len = len; if (rate > 0) audio->sample_rate = rate; __sync_synchronize(); pthread_mutex_unlock(&audio->lock); // Log peak value and first few samples for debugging float peak = 0.0f; for (int i = 0; i < len; i++) { float a = fabsf(audio->sample_buf[i]); if (a > peak) peak = a; } ac_log("[sample] loaded %d samples (%d Hz) peak=%.4f first=[%.3f,%.3f,%.3f,%.3f]\n", len, audio->sample_rate, peak, len > 0 ? audio->sample_buf[0] : 0, len > 1 ? audio->sample_buf[1] : 0, len > 2 ? audio->sample_buf[2] : 0, len > 3 ? audio->sample_buf[3] : 0);}
void audio_replay_load_data(ACAudio *audio, const float *data, int len, unsigned int rate) { if (!audio || !data || len <= 0 || !audio->replay_buf_back) return; if (len > audio->replay_max_len) len = audio->replay_max_len;
memcpy(audio->replay_buf_back, data, len * sizeof(float)); if (len < audio->replay_max_len) memset(audio->replay_buf_back + len, 0, (audio->replay_max_len - len) * sizeof(float));
pthread_mutex_lock(&audio->lock); audio->replay_voice.active = 0; float *tmp = audio->replay_buf; audio->replay_buf = audio->replay_buf_back; audio->replay_buf_back = tmp; audio->replay_len = len; if (rate > 0) audio->replay_rate = rate; __sync_synchronize(); pthread_mutex_unlock(&audio->lock);}
// --- Sample playback ---uint64_t audio_sample_play(ACAudio *audio, double freq, double base_freq, double volume, double pan, int loop) { if (!audio || audio->sample_len == 0) return 0; pthread_mutex_lock(&audio->lock);
// Find free slot (or steal oldest) int slot = -1; for (int i = 0; i < AUDIO_MAX_SAMPLE_VOICES; i++) { if (!audio->sample_voices[i].active) { slot = i; break; } } if (slot < 0) slot = 0; // steal first
SampleVoice *sv = &audio->sample_voices[slot]; sv->active = 1; sv->loop = loop; sv->position = 0.0; // Speed: pitch ratio * rate conversion (capture rate → output rate) sv->speed = (freq / base_freq) * ((double)audio->sample_rate / (double)audio->actual_rate); sv->volume = volume; sv->pan = pan; sv->fade = 0.0; sv->fade_target = 1.0; sv->id = audio->sample_next_id++;
pthread_mutex_unlock(&audio->lock); ac_log("[sample] play freq=%.1f base=%.1f speed=%.4f rate=%u/%u len=%d id=%lu\n", freq, base_freq, sv->speed, audio->sample_rate, audio->actual_rate, audio->sample_len, (unsigned long)sv->id); return sv->id;}
uint64_t audio_replay_play(ACAudio *audio, double freq, double base_freq, double volume, double pan, int loop) { if (!audio || audio->replay_len == 0) return 0; pthread_mutex_lock(&audio->lock);
SampleVoice *sv = &audio->replay_voice; sv->active = 1; sv->loop = loop; sv->position = 0.0; sv->speed = (freq / base_freq) * ((double)audio->replay_rate / (double)audio->actual_rate); sv->volume = volume; sv->pan = pan; sv->fade = 0.0; sv->fade_target = 1.0; sv->id = audio->sample_next_id++;
pthread_mutex_unlock(&audio->lock); return sv->id;}
void audio_sample_kill(ACAudio *audio, uint64_t id, double fade) { if (!audio) return; pthread_mutex_lock(&audio->lock); for (int i = 0; i < AUDIO_MAX_SAMPLE_VOICES; i++) { if (audio->sample_voices[i].active && audio->sample_voices[i].id == id) { if (fade <= 0.001) { audio->sample_voices[i].active = 0; } else { audio->sample_voices[i].fade_target = 0.0; } break; } } pthread_mutex_unlock(&audio->lock);}
void audio_replay_kill(ACAudio *audio, uint64_t id, double fade) { if (!audio) return; pthread_mutex_lock(&audio->lock); SampleVoice *sv = &audio->replay_voice; if (sv->active && sv->id == id) { if (fade <= 0.001) sv->active = 0; else sv->fade_target = 0.0; } pthread_mutex_unlock(&audio->lock);}
void audio_sample_update(ACAudio *audio, uint64_t id, double freq, double base_freq, double volume, double pan) { if (!audio) return; pthread_mutex_lock(&audio->lock); for (int i = 0; i < AUDIO_MAX_SAMPLE_VOICES; i++) { SampleVoice *sv = &audio->sample_voices[i]; if (sv->active && sv->id == id) { if (freq > 0 && base_freq > 0) sv->speed = (freq / base_freq) * ((double)audio->sample_rate / (double)audio->actual_rate); if (volume >= 0) sv->volume = volume; if (pan > -2) sv->pan = pan; break; } } pthread_mutex_unlock(&audio->lock);}
void audio_replay_update(ACAudio *audio, uint64_t id, double freq, double base_freq, double volume, double pan) { if (!audio) return; pthread_mutex_lock(&audio->lock); SampleVoice *sv = &audio->replay_voice; if (sv->active && sv->id == id) { if (freq > 0 && base_freq > 0) sv->speed = (freq / base_freq) * ((double)audio->replay_rate / (double)audio->actual_rate); if (volume >= 0) sv->volume = volume; if (pan > -2) sv->pan = pan; } pthread_mutex_unlock(&audio->lock);}
// Read current Master mixer volume as 0-100 percentagestatic int read_system_volume_card(int card) { snd_mixer_t *mixer = NULL; if (snd_mixer_open(&mixer, 0) < 0) return -1; char card_name[16]; snprintf(card_name, sizeof(card_name), "hw:%d", card); snd_mixer_attach(mixer, card_name); snd_mixer_selem_register(mixer, NULL, NULL); snd_mixer_load(mixer);
int pct = -1; snd_mixer_elem_t *elem; for (elem = snd_mixer_first_elem(mixer); elem; elem = snd_mixer_elem_next(elem)) { if (!snd_mixer_selem_is_active(elem)) continue; if (strcasecmp(snd_mixer_selem_get_name(elem), "Master") != 0) continue; if (snd_mixer_selem_has_playback_volume(elem)) { long min, max, cur; snd_mixer_selem_get_playback_volume_range(elem, &min, &max); snd_mixer_selem_get_playback_volume(elem, 0, &cur); if (max > min) pct = (int)((cur - min) * 100 / (max - min)); } break; } snd_mixer_close(mixer); return pct;}
static int muted = 0;static long pre_mute_volume = -1;
// Unmute all playback switches in the mixer — but skip jack-gated// ones so we don't re-enable the headphone DAPM path (see audio_init// above for the MAX98360A silencing story).static void unmute_all_switches(snd_mixer_t *mixer) { snd_mixer_elem_t *elem; const char *jack_gated[] = { "Headphone Jack", "Headphone Jack Switch", "HPOL Playback", "HPOR Playback", "Headset", NULL }; for (elem = snd_mixer_first_elem(mixer); elem; elem = snd_mixer_elem_next(elem)) { if (!snd_mixer_selem_is_active(elem)) continue; if (!snd_mixer_selem_has_playback_switch(elem)) continue; const char *name = snd_mixer_selem_get_name(elem); int skip = 0; for (int j = 0; jack_gated[j]; j++) { if (name && strstr(name, jack_gated[j])) { skip = 1; break; } } if (!skip) snd_mixer_selem_set_playback_switch_all(elem, 1); }}
void audio_volume_adjust(ACAudio *audio, int delta) { if (!audio || !audio->pcm) return;
char card_name[16]; snprintf(card_name, sizeof(card_name), "hw:%d", audio->card_index);
snd_mixer_t *mixer = NULL; if (snd_mixer_open(&mixer, 0) < 0) return; snd_mixer_attach(mixer, card_name); snd_mixer_selem_register(mixer, NULL, NULL); snd_mixer_load(mixer);
// Adjust ALL playback volume elements — on Realtek ALC codecs, // Master controls digital gain, Speaker/Headphone control the amplifier. // Both need to be set for audible volume change. /* RT5682 exposes "DAC1" for digital volume; SOF cards expose * "PGA*.0 * Master" pipeline PGAs. HDA laptops expose Master/PCM. * Try everything — first match wins but we run through the whole * list so volume keys work regardless of hardware. */ const char *try_names[] = {"Master", "Speaker", "Headphone", "PCM", "DAC1", "DAC2", "PGA1.0 1 Master", "PGA2.0 2 Master", "PGA5.0 5 Master", "PGA6.0 6 Master", "PGA7.0 7 Master", NULL}; int adjusted = 0; for (int n = 0; try_names[n]; n++) { snd_mixer_elem_t *elem = NULL; for (snd_mixer_elem_t *e = snd_mixer_first_elem(mixer); e; e = snd_mixer_elem_next(e)) { if (!snd_mixer_selem_is_active(e)) continue; const char *name = snd_mixer_selem_get_name(e); if (strcasecmp(name, try_names[n]) == 0 && snd_mixer_selem_has_playback_volume(e)) { elem = e; break; } } if (!elem) continue;
if (delta == 0) { // Toggle mute long min, max, cur; snd_mixer_selem_get_playback_volume_range(elem, &min, &max); snd_mixer_selem_get_playback_volume(elem, 0, &cur); if (!muted) { pre_mute_volume = cur; snd_mixer_selem_set_playback_volume_all(elem, min); } else { long restore = (pre_mute_volume > min) ? pre_mute_volume : max * 80 / 100; snd_mixer_selem_set_playback_volume_all(elem, restore); } ac_log("[audio] volume: mute toggle '%s' on %s\n", try_names[n], card_name); } else { long min, max, cur; snd_mixer_selem_get_playback_volume_range(elem, &min, &max); snd_mixer_selem_get_playback_volume(elem, 0, &cur); long step = (max - min) * 5 / 100; if (step < 1) step = 1; long newvol = cur + step * delta; if (newvol < min) newvol = min; if (newvol > max) newvol = max; snd_mixer_selem_set_playback_volume_all(elem, newvol); ac_log("[audio] volume: '%s' %ld→%ld (range %ld-%ld)\n", try_names[n], cur, newvol, min, max); } adjusted++; } if (delta == 0) { muted = !muted; } if (adjusted) { unmute_all_switches(mixer); if (delta != 0) muted = 0; } else { // No elements found — log what's available ac_log("[audio] volume: no playback elements on %s. Available:\n", card_name); for (snd_mixer_elem_t *e = snd_mixer_first_elem(mixer); e; e = snd_mixer_elem_next(e)) ac_log("[audio] %s%s\n", snd_mixer_selem_get_name(e), snd_mixer_selem_has_playback_volume(e) ? " [vol]" : ""); } snd_mixer_close(mixer);
// Update cached system volume. On SOF cards without a "Master" mixer, // read_system_volume_card returns -1. In that case, use software-only // volume: start at 100 and step ±5 with volume keys. if (muted) { audio->system_volume = 0; } else { int hw_vol = read_system_volume_card(audio->card_index); if (hw_vol >= 0) { audio->system_volume = hw_vol; } else { // No Master mixer — software gain mode (0..400%). // 150% is the default boot volume on SOF cards; allow // keys to step up to 400 (16× linear) for quiet speakers. int sv = audio->system_volume; if (sv < 0) sv = 150; int step = 10; if (delta > 0) sv = (sv + step > 400) ? 400 : sv + step; else if (delta < 0) sv = (sv - step < 0) ? 0 : sv - step; audio->system_volume = sv; ac_log("[audio] Software volume: %d%%\n", sv); } }}
void audio_boot_beep(ACAudio *audio) { if (!audio || !audio->pcm) return; // Two-tone "doo-dah" — distinct from old single ping (OTA test marker) audio_synth(audio, WAVE_SINE, 660.0, 0.12, 0.8, 0.002, 0.08, -0.15); // E5 usleep(80000); audio_synth(audio, WAVE_SINE, 990.0, 0.15, 0.9, 0.002, 0.10, 0.15); // B5}
// Prewarm: play a near-silent note so ALSA buffers are filled and readyvoid audio_prewarm(ACAudio *audio) { if (!audio || !audio->pcm) return; audio_synth(audio, WAVE_SINE, 440.0, 0.05, 0.001, 0.001, 0.04, 0.0);}
void audio_ready_melody(ACAudio *audio) { if (!audio || !audio->pcm) return; // Quick ascending 3-note toot: C5 → E5 → G5 (major triad) at full volume audio_synth(audio, WAVE_TRIANGLE, 523.25, 0.15, 0.7, 0.003, 0.10, -0.2); // C5 usleep(60000); // 60ms gap audio_synth(audio, WAVE_TRIANGLE, 659.25, 0.15, 0.7, 0.003, 0.10, 0.0); // E5 usleep(60000); audio_synth(audio, WAVE_TRIANGLE, 783.99, 0.20, 0.8, 0.003, 0.14, 0.2); // G5}
void audio_shutdown_sound(ACAudio *audio) { if (!audio || !audio->pcm) return; // Descending 3-note chime: G5 → E5 → C5 at full volume audio_synth(audio, WAVE_TRIANGLE, 783.99, 0.15, 0.7, 0.003, 0.10, 0.2); // G5 usleep(60000); audio_synth(audio, WAVE_TRIANGLE, 659.25, 0.15, 0.7, 0.003, 0.10, 0.0); // E5 usleep(60000); audio_synth(audio, WAVE_TRIANGLE, 523.25, 0.20, 0.8, 0.003, 0.14, -0.2); // C5 // Wait for notes to finish playing before shutdown usleep(250000);}
// Save sample buffer to disk as raw floats with a small header// Format: [uint32_t sample_rate] [uint32_t sample_len] [float * sample_len]int audio_sample_save(ACAudio *audio, const char *path) { if (!audio || !audio->sample_buf || audio->sample_len <= 0) return -1; FILE *f = fopen(path, "wb"); if (!f) return -1; uint32_t rate = (uint32_t)audio->sample_rate; uint32_t len = (uint32_t)audio->sample_len; fwrite(&rate, sizeof(rate), 1, f); fwrite(&len, sizeof(len), 1, f); fwrite(audio->sample_buf, sizeof(float), len, f); fclose(f); sync(); return (int)len;}
// Load sample buffer from diskint audio_sample_load(ACAudio *audio, const char *path) { if (!audio || !audio->sample_buf) return -1; FILE *f = fopen(path, "rb"); if (!f) return -1; uint32_t rate, len; if (fread(&rate, sizeof(rate), 1, f) != 1 || fread(&len, sizeof(len), 1, f) != 1) { fclose(f); return -1; } if (len > (uint32_t)audio->sample_max_len) len = (uint32_t)audio->sample_max_len; if (fread(audio->sample_buf, sizeof(float), len, f) != len) { fclose(f); return -1; } fclose(f); audio->sample_len = (int)len; audio->sample_rate = (int)rate; return (int)len;}
// --- DJ deck API ---
int audio_deck_load(ACAudio *audio, int deck, const char *path) { if (!audio || deck < 0 || deck >= AUDIO_MAX_DECKS) return -1; ACDeck *dk = &audio->decks[deck];
// Create decoder if needed if (!dk->decoder) { dk->decoder = deck_decoder_create(audio->actual_rate); if (!dk->decoder) return -1; }
dk->playing = 0; dk->active = 0; int ret = deck_decoder_load(dk->decoder, path); if (ret == 0) { dk->active = 1; // Generate waveform peaks for visualization. Skip for live streams // (radio): the peak pass reads the source to EOF, which never comes // on an endless Icecast feed and would hang the caller. if (!dk->decoder->is_stream) deck_decoder_generate_peaks(dk->decoder, 1024); } return ret;}
void audio_deck_play(ACAudio *audio, int deck) { if (!audio || deck < 0 || deck >= AUDIO_MAX_DECKS) return; ACDeck *dk = &audio->decks[deck]; if (!dk->active || !dk->decoder) return; dk->playing = 1; deck_decoder_play(dk->decoder);}
void audio_deck_pause(ACAudio *audio, int deck) { if (!audio || deck < 0 || deck >= AUDIO_MAX_DECKS) return; ACDeck *dk = &audio->decks[deck]; if (!dk->decoder) return; dk->playing = 0; deck_decoder_pause(dk->decoder);}
void audio_deck_seek(ACAudio *audio, int deck, double seconds) { if (!audio || deck < 0 || deck >= AUDIO_MAX_DECKS) return; ACDeck *dk = &audio->decks[deck]; if (!dk->active || !dk->decoder) return; deck_decoder_seek(dk->decoder, seconds);}
void audio_deck_set_speed(ACAudio *audio, int deck, double speed) { if (!audio || deck < 0 || deck >= AUDIO_MAX_DECKS) return; ACDeck *dk = &audio->decks[deck]; if (!dk->decoder) return; deck_decoder_set_speed(dk->decoder, speed);}
void audio_deck_set_volume(ACAudio *audio, int deck, float vol) { if (!audio || deck < 0 || deck >= AUDIO_MAX_DECKS) return; if (vol < 0.0f) vol = 0.0f; if (vol > 1.0f) vol = 1.0f; audio->decks[deck].volume = vol;}
void audio_deck_set_crossfader(ACAudio *audio, float value) { if (!audio) return; if (value < 0.0f) value = 0.0f; if (value > 1.0f) value = 1.0f; audio->crossfader = value;}
void audio_deck_set_master_volume(ACAudio *audio, float value) { if (!audio) return; if (value < 0.0f) value = 0.0f; if (value > 1.0f) value = 1.0f; audio->deck_master_volume = value;}
void audio_destroy(ACAudio *audio) { if (!audio) return; audio->running = 0; audio_mic_close(audio); // Destroy DJ decks for (int d = 0; d < AUDIO_MAX_DECKS; d++) { if (audio->decks[d].decoder) { deck_decoder_destroy(audio->decks[d].decoder); audio->decks[d].decoder = NULL; } } if (audio->pcm) { pthread_join(audio->thread, NULL); snd_pcm_close((snd_pcm_t *)audio->pcm); } if (audio->headphone_pcm) snd_pcm_close((snd_pcm_t *)audio->headphone_pcm); if (audio->hdmi_pcm) snd_pcm_close((snd_pcm_t *)audio->hdmi_pcm); free(audio->room_buf_l); free(audio->room_buf_r); free(audio->sample_buf); free(audio->sample_buf_back); free(audio->mic_ring); free(audio->replay_buf); free(audio->replay_buf_back); free(audio->output_history_buf); free(audio->tts_buf); pthread_mutex_destroy(&audio->lock); free(audio);}