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Isolate /models synth variants and revert main.

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This commit is contained in:
b1rdmania
2025-12-20 12:21:39 +00:00
parent b7a79e93c9
commit 633197b81a
6 changed files with 530 additions and 267 deletions
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index.html
+1 -10
View File
@@ -84,12 +84,6 @@
.topbar h1 {
margin: 0;
}
.topbar-actions {
margin-left: auto;
display: inline-flex;
align-items: center;
gap: 8px;
}
.faq-link {
background: transparent;
border: 1px solid rgba(255,255,255,0.14);
@@ -825,10 +819,7 @@
<div class="container">
<div class="topbar">
<h1>🎵 MOTIF</h1>
<div class="topbar-actions">
<a class="faq-link" href="/models" style="text-decoration:none;" aria-label="Open test models page">Models</a>
<button id="faqBtn" class="faq-link" type="button">FAQ</button>
</div>
<button id="faqBtn" class="faq-link" type="button">FAQ</button>
</div>
<p>Procedural Music Synthesis from MIDI Structure</p>
src/core/MotifEngine.ts
+4 -8
View File
@@ -1,4 +1,4 @@
import type { NoteEvent, MotifConfig, SynthModel } from '../types';
import type { NoteEvent, MotifConfig } from '../types';
import { MIDIProcessor } from '../midi/MIDIProcessor';
import { MIDIParser } from '../midi/MIDIParser';
import { MIDIService } from '../services/MIDIService';
@@ -27,17 +27,13 @@ export class MotifEngine {
this.roleMapper = new RoleMapper();
}
async generateFromMIDI(
events: NoteEvent[],
transformMode: 'passthrough' | 'procedural' = 'passthrough',
model: SynthModel = 'nes_gb'
): Promise<void> {
async generateFromMIDI(events: NoteEvent[], transformMode: 'passthrough' | 'procedural' = 'passthrough'): Promise<void> {
// Initialize audio context using shared unlock (iOS compatibility)
if (!this.audioContext) {
this.audioContext = await unlockAudio();
}
this.synthesisEngine = new SynthesisEngine(this.audioContext, this.config, model);
this.synthesisEngine = new SynthesisEngine(this.audioContext, this.config);
if (transformMode === 'passthrough') {
// Direct playback mode - play MIDI as-is without transformations
@@ -111,7 +107,7 @@ export class MotifEngine {
this.audioContext = await unlockAudio();
}
this.synthesisEngine = new SynthesisEngine(this.audioContext, this.config, 'nes_gb');
this.synthesisEngine = new SynthesisEngine(this.audioContext, this.config);
this.synthesisEngine.setupLayers(roleAssignments);
}
src/models.ts
+25 -8
View File
@@ -1,13 +1,19 @@
import { MotifEngine } from './core/MotifEngine';
import { MIDIService } from './services/MIDIService';
import { MIDIParser } from './midi/MIDIParser';
import { SoundfontMIDIPlayer } from './synthesis/SoundfontMIDIPlayer';
import { getAudioContext, isAudioReady, unlockAudio } from './utils/audioUnlock';
import type { NoteEvent, SynthModel } from './types';
import { MIDIProcessor } from './midi/MIDIProcessor';
import { RoleMapper } from './core/RoleMapper';
import { TestModelSynthesisEngine } from './synthesis/TestModelSynthesisEngine';
import type { NoteEvent } from './types';
type SynthModel = 'pre8bit' | 'nes_gb' | 'snes_ish';
class ModelsApp {
private motifEngine: MotifEngine;
private midiService: MIDIService;
private midiProcessor: MIDIProcessor;
private roleMapper: RoleMapper;
private testEngine: TestModelSynthesisEngine | null = null;
private soundfontPlayer: SoundfontMIDIPlayer | null = null;
@@ -44,8 +50,9 @@ class ModelsApp {
private currentMIDI: { events: NoteEvent[]; metadata: any } | null = null;
constructor() {
this.motifEngine = new MotifEngine();
this.midiService = new MIDIService();
this.midiProcessor = new MIDIProcessor();
this.roleMapper = new RoleMapper();
this.initializeUI();
this.setupEventListeners();
this.syncModelHint();
@@ -106,7 +113,7 @@ class ModelsApp {
this.motifStopBtn.addEventListener('click', () => this.handleMotifStop());
this.motifVolumeSlider.addEventListener('input', (e) => {
const volume = parseFloat((e.target as HTMLInputElement).value);
this.motifEngine.setVolume(volume);
this.testEngine?.setVolume(volume);
});
this.modelSelect.addEventListener('change', () => this.syncModelHint());
@@ -350,8 +357,17 @@ class ModelsApp {
this.updateStatus(`Generating Motif (${model})...`);
this.motifBtn.disabled = true;
await this.motifEngine.generateFromMIDI(this.currentMIDI.events, 'procedural', model);
await this.motifEngine.play();
// Ensure the previous model engine is stopped/cleared so each run is isolated.
this.handleMotifStop();
const audioContext = getAudioContext();
const features = this.midiProcessor.extractFeatures(this.currentMIDI.events);
const assignments = this.roleMapper.assignRoles(features, this.currentMIDI.events);
this.testEngine = new TestModelSynthesisEngine(audioContext, model);
this.testEngine.setupLayers(assignments);
this.testEngine.setVolume(parseFloat(this.motifVolumeSlider.value));
this.testEngine.start();
this.motifStopBtn.disabled = false;
this.updateStatus(`Playing Motif (${model})...`);
@@ -362,7 +378,8 @@ class ModelsApp {
}
private handleMotifStop(): void {
this.motifEngine.stop();
this.testEngine?.stop();
this.testEngine = null;
this.motifBtn.disabled = false;
this.motifStopBtn.disabled = true;
}
src/synthesis/SynthesisEngine.ts
+69 -238
View File
@@ -1,52 +1,31 @@
import type { RoleAssignment, MotifConfig, SynthLayer, Role, NoteEvent, ChordEvent, SynthModel } from '../types';
import type { RoleAssignment, MotifConfig, SynthLayer, Role, NoteEvent, ChordEvent } from '../types';
export class SynthesisEngine {
private audioContext: AudioContext;
private config: MotifConfig;
private masterGain: GainNode;
private postGain: GainNode;
private model: SynthModel;
private layers: Map<Role, SynthLayer> = new Map();
private roleAssignments: Map<Role, RoleAssignment> = new Map();
private isPlaying = false;
private schedulerIntervalId: number | null = null;
private startTime = 0;
private nextEventIndex = new Map<Role, number>();
private activeVoiceCount = 0;
private maxVoices: number;
private effectCleanup: (() => void) | null = null;
constructor(audioContext: AudioContext, config: MotifConfig, model: SynthModel = 'nes_gb') {
constructor(audioContext: AudioContext, config: MotifConfig) {
this.audioContext = audioContext;
this.config = config;
this.masterGain = audioContext.createGain();
this.postGain = audioContext.createGain();
this.postGain.connect(audioContext.destination);
this.model = model;
this.maxVoices = this.getMaxVoicesForModel(model, config.maxOscillators);
// Default overall level
this.masterGain.connect(audioContext.destination);
this.masterGain.gain.value = 0.3;
this.postGain.gain.value = 1.0;
// Route + optional effects
this.effectCleanup = this.configureMasterChain(model);
}
setupLayers(assignments: RoleAssignment[]): void {
// Clean up existing layers
this.cleanupLayers();
// Reset voice budgeting per setup (important when switching models)
this.activeVoiceCount = 0;
// Apply model role filtering
const filteredAssignments = this.filterAssignmentsForModel(assignments);
// Find the earliest event time across all assignments
let earliestTime = Infinity;
for (const assignment of filteredAssignments) {
for (const assignment of assignments) {
if (assignment.events.length > 0) {
earliestTime = Math.min(earliestTime, assignment.events[0].time);
}
@@ -58,7 +37,7 @@ export class SynthesisEngine {
// If we found events, normalize times to start at 0
if (earliestTime !== Infinity && earliestTime > 0) {
console.log('Normalizing event times, earliest was:', earliestTime);
for (const assignment of filteredAssignments) {
for (const assignment of assignments) {
// Normalize note events
for (const event of assignment.events) {
event.time -= earliestTime;
@@ -71,7 +50,7 @@ export class SynthesisEngine {
}
// Store role assignments and create layers
for (const assignment of filteredAssignments) {
for (const assignment of assignments) {
const layer = this.createSynthLayer(assignment.role);
this.layers.set(assignment.role, layer);
this.roleAssignments.set(assignment.role, assignment);
@@ -196,62 +175,37 @@ export class SynthesisEngine {
}
private configureLayerForRole(gain: GainNode, filter: BiquadFilterNode, role: Role): void {
// Default per-model filter shaping (keeps presets recognizable)
if (this.model === 'pre8bit') {
// Very bright, very simple
filter.type = 'lowpass';
filter.frequency.value = 6000;
filter.Q.value = 0.8;
} else if (this.model === 'snes_ish') {
// Warmer, a little more body
filter.type = 'lowpass';
filter.frequency.value = 2400;
filter.Q.value = 0.9;
}
switch (role) {
case 'bass':
gain.gain.value = this.model === 'pre8bit' ? 0.5 : 0.4;
if (this.model !== 'pre8bit') {
filter.type = 'lowpass';
filter.frequency.value = this.model === 'snes_ish' ? 260 : 200;
} else {
filter.frequency.value = 350;
}
gain.gain.value = 0.4;
filter.type = 'lowpass';
filter.frequency.value = 200;
break;
case 'drone':
gain.gain.value = this.model === 'pre8bit' ? 0.0 : 0.2;
if (this.model !== 'pre8bit') {
filter.type = 'bandpass';
filter.frequency.value = this.model === 'snes_ish' ? 520 : 400;
}
gain.gain.value = 0.2;
filter.type = 'bandpass';
filter.frequency.value = 400;
break;
case 'ostinato':
gain.gain.value = this.model === 'pre8bit' ? 0.25 : 0.3;
if (this.model !== 'pre8bit') {
filter.type = 'highpass';
filter.frequency.value = this.model === 'snes_ish' ? 220 : 300;
}
gain.gain.value = 0.3;
filter.type = 'highpass';
filter.frequency.value = 300;
break;
case 'texture':
gain.gain.value = this.model === 'pre8bit' ? 0.0 : 0.1;
if (this.model !== 'pre8bit') {
filter.type = 'bandpass';
filter.frequency.value = this.model === 'snes_ish' ? 900 : 800;
}
gain.gain.value = 0.1;
filter.type = 'bandpass';
filter.frequency.value = 800;
break;
case 'accents':
gain.gain.value = this.model === 'pre8bit' ? 0.35 : 0.5;
if (this.model !== 'pre8bit') {
filter.type = 'peaking';
filter.frequency.value = this.model === 'snes_ish' ? 1200 : 1000;
}
gain.gain.value = 0.5;
filter.type = 'peaking';
filter.frequency.value = 1000;
break;
case 'melody':
// Passthrough mode - balanced sound for all notes
gain.gain.value = this.model === 'pre8bit' ? 0.4 : 0.35;
gain.gain.value = 0.35;
filter.type = 'lowpass';
filter.frequency.value = this.model === 'snes_ish' ? 3200 : 4000; // Brighter for chip, warmer for SNES-ish
filter.frequency.value = 4000; // Brighter sound for full range
break;
}
}
@@ -263,13 +217,6 @@ export class SynthesisEngine {
private scheduleNote(role: Role, pitch: number, duration: number, velocity: number, when: number): void {
const layer = this.layers.get(role);
if (!layer) return;
// Model gating: pre8bit runs intentionally sparse
if (this.model === 'pre8bit') {
if (role !== 'bass' && role !== 'melody') return;
}
if (this.activeVoiceCount >= this.maxVoices) return;
const osc = this.audioContext.createOscillator();
const envelope = this.audioContext.createGain();
@@ -278,50 +225,33 @@ export class SynthesisEngine {
const frequency = this.midiToFrequency(pitch);
osc.frequency.value = frequency;
// Choose oscillator type based on model + role
if (this.model === 'pre8bit') {
osc.type = role === 'bass' ? 'triangle' : 'square';
} else if (this.model === 'snes_ish') {
// Warmer “sample-ish” feel: richer waveforms + filtering + echo on master
if (role === 'bass') osc.type = 'triangle';
else if (role === 'drone') osc.type = 'sawtooth';
else if (role === 'ostinato') osc.type = 'triangle';
else if (role === 'melody') osc.type = 'sawtooth';
else osc.type = 'sine';
// Subtle detune (feels less “pure chip”)
osc.detune.value = (Math.random() - 0.5) * 8; // ±4 cents
} else {
// nes_gb (current default)
switch (role) {
case 'bass':
osc.type = 'square';
break;
case 'drone':
osc.type = 'sawtooth';
break;
case 'ostinato':
osc.type = 'triangle';
break;
case 'melody':
osc.type = 'triangle';
break;
case 'texture':
case 'accents':
osc.type = 'sine';
break;
}
// Choose oscillator type based on role
switch (role) {
case 'bass':
osc.type = 'square';
break;
case 'drone':
osc.type = 'sawtooth';
break;
case 'ostinato':
osc.type = 'triangle';
break;
case 'melody':
osc.type = 'triangle';
break;
case 'texture':
case 'accents':
osc.type = 'sine';
break;
}
osc.connect(envelope);
envelope.connect(layer.filterNode);
// Envelope tuned per model (still with minimum times to prevent clicks)
// Envelope based on velocity and duration with minimum times to prevent clicks
const gainValue = velocity * 0.5; // Scale velocity
const attackBase = this.model === 'pre8bit' ? 0.003 : this.model === 'snes_ish' ? 0.01 : 0.005;
const releaseBase = this.model === 'pre8bit' ? 0.008 : this.model === 'snes_ish' ? 0.14 : 0.01;
const attackTime = Math.max(attackBase, Math.min(0.06, duration * 0.1));
const releaseTime = Math.max(releaseBase, Math.min(this.model === 'snes_ish' ? 0.22 : 0.12, duration * 0.3));
const attackTime = Math.max(0.005, Math.min(0.05, duration * 0.1)); // Min 5ms attack
const releaseTime = Math.max(0.01, Math.min(0.1, duration * 0.3)); // Min 10ms release
envelope.gain.setValueAtTime(0, when);
envelope.gain.linearRampToValueAtTime(gainValue, when + attackTime);
@@ -330,8 +260,6 @@ export class SynthesisEngine {
osc.start(when);
osc.stop(when + duration + releaseTime + 0.01); // Stop after envelope completes
this.activeVoiceCount++;
// Clean up after note ends
setTimeout(() => {
@@ -341,7 +269,6 @@ export class SynthesisEngine {
} catch (e) {
// Already disconnected
}
this.activeVoiceCount = Math.max(0, this.activeVoiceCount - 1);
}, (duration + releaseTime + 0.1) * 1000);
}
@@ -362,12 +289,6 @@ export class SynthesisEngine {
const chords = assignment.chords;
if (!events.length && !chords.length) return;
// pre8bit is intentionally simple: no chord scheduling
if (this.model === 'pre8bit') {
this.scheduleSingleEvents(role, events, scheduleUntil);
return;
}
// For roles that support polyphony (drone, texture), prefer chords
if ((role === 'drone' || role === 'texture') && chords.length > 0) {
@@ -471,13 +392,9 @@ export class SynthesisEngine {
private scheduleChord(role: Role, pitches: number[], duration: number, velocity: number, when: number): void {
const layer = this.layers.get(role);
if (!layer) return;
if (this.activeVoiceCount >= this.maxVoices) return;
// Create oscillator for each pitch in the chord (unless constrained)
const chordPitches = this.model === 'snes_ish' ? pitches.slice(0, 4) : pitches.slice(0, 3);
for (const pitch of chordPitches) {
if (this.activeVoiceCount >= this.maxVoices) break;
// Create oscillator for each pitch in the chord
for (const pitch of pitches) {
const osc = this.audioContext.createOscillator();
const envelope = this.audioContext.createGain();
@@ -485,46 +402,35 @@ export class SynthesisEngine {
const frequency = this.midiToFrequency(pitch);
osc.frequency.value = frequency;
// Choose oscillator type based on model + role (same as note path)
if (this.model === 'snes_ish') {
if (role === 'bass') osc.type = 'triangle';
else if (role === 'drone') osc.type = 'sawtooth';
else if (role === 'ostinato') osc.type = 'triangle';
else if (role === 'melody') osc.type = 'sawtooth';
else osc.type = 'sine';
osc.detune.value = (Math.random() - 0.5) * 8;
} else {
switch (role) {
case 'bass':
osc.type = 'square';
break;
case 'drone':
osc.type = 'sawtooth';
break;
case 'ostinato':
osc.type = 'triangle';
break;
case 'texture':
osc.type = 'sine';
break;
case 'melody':
osc.type = 'triangle';
break;
case 'accents':
osc.type = 'sine';
break;
}
// Choose oscillator type based on role
switch (role) {
case 'bass':
osc.type = 'square';
break;
case 'drone':
osc.type = 'sawtooth';
break;
case 'ostinato':
osc.type = 'triangle';
break;
case 'texture':
osc.type = 'sine';
break;
case 'melody':
osc.type = 'triangle';
break;
case 'accents':
osc.type = 'sine';
break;
}
osc.connect(envelope);
envelope.connect(layer.filterNode);
// Envelope based on velocity and duration, scaled for chords with minimum times to prevent clicks
const gainValue = (velocity * 0.3) / Math.max(chordPitches.length * 0.5, 1); // Scale down for chords
const attackBase = this.model === 'snes_ish' ? 0.01 : 0.005;
const releaseBase = this.model === 'snes_ish' ? 0.16 : 0.01;
const attackTime = Math.max(attackBase, Math.min(0.06, duration * 0.1));
const releaseTime = Math.max(releaseBase, Math.min(this.model === 'snes_ish' ? 0.24 : 0.12, duration * 0.3));
const gainValue = (velocity * 0.3) / Math.max(pitches.length * 0.5, 1); // Scale down for chords
const attackTime = Math.max(0.005, Math.min(0.05, duration * 0.1)); // Min 5ms attack
const releaseTime = Math.max(0.01, Math.min(0.1, duration * 0.3)); // Min 10ms release
envelope.gain.setValueAtTime(0, when);
envelope.gain.linearRampToValueAtTime(gainValue, when + attackTime);
@@ -534,8 +440,6 @@ export class SynthesisEngine {
osc.start(when);
osc.stop(when + duration + releaseTime + 0.01); // Stop after envelope completes
this.activeVoiceCount++;
// Clean up after note ends
setTimeout(() => {
try {
@@ -544,7 +448,6 @@ export class SynthesisEngine {
} catch (e) {
// Already disconnected
}
this.activeVoiceCount = Math.max(0, this.activeVoiceCount - 1);
}, (duration + releaseTime + 0.1) * 1000);
}
}
@@ -564,76 +467,4 @@ export class SynthesisEngine {
}
this.layers.clear();
}
private getMaxVoicesForModel(model: SynthModel, defaultMax: number): number {
if (model === 'pre8bit') return Math.min(2, defaultMax);
if (model === 'snes_ish') return Math.max(12, defaultMax);
return defaultMax;
}
private filterAssignmentsForModel(assignments: RoleAssignment[]): RoleAssignment[] {
if (this.model === 'pre8bit') {
// Keep it intentionally simple and sparse.
const keep: Role[] = ['melody', 'bass'];
const kept = assignments.filter(a => keep.includes(a.role));
// If role mapper didn’t produce those roles, fall back to first available assignment.
if (kept.length > 0) return kept.slice(0, 2);
return assignments.slice(0, 1);
}
return assignments;
}
private configureMasterChain(model: SynthModel): () => void {
// Disconnect any previous chain
try { this.masterGain.disconnect(); } catch {}
if (this.effectCleanup) {
try { this.effectCleanup(); } catch {}
}
// Default: dry only
if (model !== 'snes_ish') {
this.masterGain.connect(this.postGain);
return () => {
try { this.masterGain.disconnect(); } catch {}
};
}
// SNES-ish: add a simple echo/reverb-like feedback delay with filtering.
const dry = this.audioContext.createGain();
const wet = this.audioContext.createGain();
const delay = this.audioContext.createDelay(1.0);
const feedback = this.audioContext.createGain();
const fbFilter = this.audioContext.createBiquadFilter();
dry.gain.value = 0.85;
wet.gain.value = 0.28;
delay.delayTime.value = 0.165; // ~165ms echo
feedback.gain.value = 0.32;
fbFilter.type = 'lowpass';
fbFilter.frequency.value = 1800;
fbFilter.Q.value = 0.7;
// master -> dry -> post
this.masterGain.connect(dry);
dry.connect(this.postGain);
// master -> delay -> wet -> post
this.masterGain.connect(delay);
delay.connect(wet);
wet.connect(this.postGain);
// feedback loop: delay -> filter -> feedback -> delay
delay.connect(fbFilter);
fbFilter.connect(feedback);
feedback.connect(delay);
return () => {
try { this.masterGain.disconnect(); } catch {}
try { dry.disconnect(); } catch {}
try { wet.disconnect(); } catch {}
try { delay.disconnect(); } catch {}
try { feedback.disconnect(); } catch {}
try { fbFilter.disconnect(); } catch {}
};
}
}
src/synthesis/TestModelSynthesisEngine.ts
+431
View File
@@ -0,0 +1,431 @@
import type { RoleAssignment, Role, SynthLayer, NoteEvent, ChordEvent } from '../types';
export type SynthModel = 'pre8bit' | 'nes_gb' | 'snes_ish';
/**
* TestModelSynthesisEngine
* -----------------------
* Used ONLY by /models to compare different synthesis “models”.
* This is intentionally isolated from the main `SynthesisEngine` so the main app stays stable.
*/
export class TestModelSynthesisEngine {
private audioContext: AudioContext;
private model: SynthModel;
private masterGain: GainNode;
private postGain: GainNode;
private layers: Map<Role, SynthLayer> = new Map();
private roleAssignments: Map<Role, RoleAssignment> = new Map();
private isPlaying = false;
private schedulerIntervalId: number | null = null;
private startTime = 0;
private nextEventIndex = new Map<Role, number>();
private activeVoiceCount = 0;
private maxVoices: number;
// scheduling config (kept simple for /models)
private lookaheadTime = 0.12;
private scheduleInterval = 25;
private fadeTime = 0.05;
constructor(audioContext: AudioContext, model: SynthModel) {
this.audioContext = audioContext;
this.model = model;
this.masterGain = audioContext.createGain();
this.postGain = audioContext.createGain();
this.postGain.connect(audioContext.destination);
this.masterGain.gain.value = 0.3;
this.postGain.gain.value = 1.0;
this.maxVoices = this.model === 'pre8bit' ? 2 : this.model === 'snes_ish' ? 14 : 8;
this.configureMasterChain();
}
setVolume(volume: number): void {
this.masterGain.gain.value = Math.max(0, Math.min(1, volume));
}
setupLayers(assignments: RoleAssignment[]): void {
this.cleanupLayers();
this.activeVoiceCount = 0;
const filtered = this.filterAssignments(assignments);
let earliestTime = Infinity;
for (const assignment of filtered) {
if (assignment.events.length > 0) earliestTime = Math.min(earliestTime, assignment.events[0].time);
if (assignment.chords.length > 0) earliestTime = Math.min(earliestTime, assignment.chords[0].time);
}
if (earliestTime !== Infinity && earliestTime > 0) {
for (const assignment of filtered) {
for (const e of assignment.events) e.time -= earliestTime;
for (const c of assignment.chords) c.time -= earliestTime;
}
}
for (const assignment of filtered) {
const layer = this.createSynthLayer(assignment.role);
this.layers.set(assignment.role, layer);
this.roleAssignments.set(assignment.role, assignment);
this.nextEventIndex.set(assignment.role, 0);
}
}
start(): void {
if (this.isPlaying) return;
this.isPlaying = true;
this.startTime = this.audioContext.currentTime;
for (const role of this.roleAssignments.keys()) {
this.nextEventIndex.set(role, 0);
}
this.schedulerIntervalId = window.setInterval(() => this.scheduleEvents(), this.scheduleInterval);
}
stop(): void {
if (!this.isPlaying) return;
this.isPlaying = false;
if (this.schedulerIntervalId) {
clearInterval(this.schedulerIntervalId);
this.schedulerIntervalId = null;
}
this.fadeOutAllLayers();
}
private configureMasterChain(): void {
try { this.masterGain.disconnect(); } catch {}
// dry always
const dry = this.audioContext.createGain();
dry.gain.value = 1.0;
this.masterGain.connect(dry);
dry.connect(this.postGain);
if (this.model !== 'snes_ish') return;
// SNES-ish echo: feedback delay with a lowpass in the loop.
const wet = this.audioContext.createGain();
const delay = this.audioContext.createDelay(1.0);
const feedback = this.audioContext.createGain();
const fbFilter = this.audioContext.createBiquadFilter();
wet.gain.value = 0.26;
delay.delayTime.value = 0.165;
feedback.gain.value = 0.32;
fbFilter.type = 'lowpass';
fbFilter.frequency.value = 1800;
fbFilter.Q.value = 0.7;
this.masterGain.connect(delay);
delay.connect(wet);
wet.connect(this.postGain);
delay.connect(fbFilter);
fbFilter.connect(feedback);
feedback.connect(delay);
}
private filterAssignments(assignments: RoleAssignment[]): RoleAssignment[] {
if (this.model !== 'pre8bit') return assignments;
const keep: Role[] = ['melody', 'bass'];
const kept = assignments.filter(a => keep.includes(a.role));
if (kept.length > 0) return kept.slice(0, 2);
return assignments.slice(0, 1);
}
private createSynthLayer(role: Role): SynthLayer {
const gainNode = this.audioContext.createGain();
const filterNode = this.audioContext.createBiquadFilter();
filterNode.connect(gainNode);
gainNode.connect(this.masterGain);
this.configureLayerForRole(gainNode, filterNode, role);
return { role, oscillators: [], gainNode, filterNode };
}
private configureLayerForRole(gain: GainNode, filter: BiquadFilterNode, role: Role): void {
// Base curve per model
if (this.model === 'pre8bit') {
filter.type = 'lowpass';
filter.frequency.value = 6500;
filter.Q.value = 0.8;
} else if (this.model === 'snes_ish') {
filter.type = 'lowpass';
filter.frequency.value = 2600;
filter.Q.value = 0.9;
}
switch (role) {
case 'bass':
gain.gain.value = this.model === 'pre8bit' ? 0.55 : 0.4;
if (this.model !== 'pre8bit') {
filter.type = 'lowpass';
filter.frequency.value = this.model === 'snes_ish' ? 260 : 200;
} else {
filter.frequency.value = 420;
}
break;
case 'drone':
gain.gain.value = this.model === 'pre8bit' ? 0.0 : 0.2;
if (this.model !== 'pre8bit') {
filter.type = 'bandpass';
filter.frequency.value = this.model === 'snes_ish' ? 520 : 400;
}
break;
case 'ostinato':
gain.gain.value = this.model === 'pre8bit' ? 0.25 : 0.3;
if (this.model !== 'pre8bit') {
filter.type = 'highpass';
filter.frequency.value = this.model === 'snes_ish' ? 220 : 300;
}
break;
case 'texture':
gain.gain.value = this.model === 'pre8bit' ? 0.0 : 0.1;
if (this.model !== 'pre8bit') {
filter.type = 'bandpass';
filter.frequency.value = this.model === 'snes_ish' ? 900 : 800;
}
break;
case 'accents':
gain.gain.value = this.model === 'pre8bit' ? 0.35 : 0.5;
if (this.model !== 'pre8bit') {
filter.type = 'peaking';
filter.frequency.value = this.model === 'snes_ish' ? 1200 : 1000;
}
break;
case 'melody':
gain.gain.value = this.model === 'pre8bit' ? 0.42 : 0.35;
filter.type = 'lowpass';
filter.frequency.value = this.model === 'snes_ish' ? 3200 : 4200;
break;
}
}
private midiToFrequency(midiNote: number): number {
return 440 * Math.pow(2, (midiNote - 69) / 12);
}
private scheduleEvents(): void {
if (!this.isPlaying) return;
const currentTime = this.audioContext.currentTime;
const scheduleUntil = currentTime + this.lookaheadTime;
for (const [role, assignment] of this.roleAssignments) {
this.scheduleRoleEvents(role, assignment, scheduleUntil);
}
}
private scheduleRoleEvents(role: Role, assignment: RoleAssignment, scheduleUntil: number): void {
const events = assignment.events;
const chords = assignment.chords;
if (!events.length && !chords.length) return;
if (this.model === 'pre8bit') {
this.scheduleSingleEvents(role, events, scheduleUntil);
return;
}
if ((role === 'drone' || role === 'texture') && chords.length > 0) {
this.scheduleChordEvents(role, chords, scheduleUntil);
} else {
this.scheduleSingleEvents(role, events, scheduleUntil);
}
}
private scheduleChordEvents(role: Role, chords: ChordEvent[], scheduleUntil: number): void {
let chordIndex = this.nextEventIndex.get(role) || 0;
while (chordIndex < chords.length) {
const chord = chords[chordIndex];
const eventTime = this.startTime + chord.time;
if (eventTime > scheduleUntil) break;
if (eventTime >= this.audioContext.currentTime) {
this.scheduleChord(role, chord.pitches, Math.max(0.05, chord.duration), chord.velocity, eventTime);
}
chordIndex++;
}
this.nextEventIndex.set(role, chordIndex);
if (chordIndex >= chords.length) this.loopIfEnded(chords.length);
}
private scheduleSingleEvents(role: Role, events: NoteEvent[], scheduleUntil: number): void {
let eventIndex = this.nextEventIndex.get(role) || 0;
while (eventIndex < events.length) {
const event = events[eventIndex];
const eventTime = this.startTime + event.time;
if (eventTime > scheduleUntil) break;
if (eventTime >= this.audioContext.currentTime) {
this.scheduleNote(role, event.pitch, Math.max(0.05, event.duration), event.velocity, eventTime);
}
eventIndex++;
}
this.nextEventIndex.set(role, eventIndex);
if (eventIndex >= events.length) this.loopIfEnded(events.length);
}
private loopIfEnded(length: number): void {
if (length <= 0) return;
// If all roles looped, reset startTime.
if (Array.from(this.nextEventIndex.values()).every(idx => idx === 0 || idx >= length)) {
for (const role of this.nextEventIndex.keys()) this.nextEventIndex.set(role, 0);
this.startTime = this.audioContext.currentTime;
}
}
private scheduleNote(role: Role, pitch: number, duration: number, velocity: number, when: number): void {
const layer = this.layers.get(role);
if (!layer) return;
if (this.model === 'pre8bit') {
if (role !== 'bass' && role !== 'melody') return;
}
if (this.activeVoiceCount >= this.maxVoices) return;
const osc = this.audioContext.createOscillator();
const envelope = this.audioContext.createGain();
osc.frequency.value = this.midiToFrequency(pitch);
// Model-specific voice
if (this.model === 'pre8bit') {
osc.type = role === 'bass' ? 'triangle' : 'square';
} else if (this.model === 'snes_ish') {
if (role === 'bass') osc.type = 'triangle';
else if (role === 'melody') osc.type = 'sawtooth';
else if (role === 'drone') osc.type = 'sawtooth';
else if (role === 'ostinato') osc.type = 'triangle';
else osc.type = 'sine';
osc.detune.value = (Math.random() - 0.5) * 8;
} else {
// nes_gb
if (role === 'bass') osc.type = 'square';
else if (role === 'drone') osc.type = 'sawtooth';
else if (role === 'ostinato') osc.type = 'triangle';
else if (role === 'melody') osc.type = 'triangle';
else osc.type = 'sine';
}
osc.connect(envelope);
envelope.connect(layer.filterNode);
const gainValue = velocity * 0.5;
const attackBase = this.model === 'pre8bit' ? 0.003 : this.model === 'snes_ish' ? 0.01 : 0.005;
const releaseBase = this.model === 'pre8bit' ? 0.008 : this.model === 'snes_ish' ? 0.14 : 0.01;
const attackTime = Math.max(attackBase, Math.min(0.06, duration * 0.1));
const releaseTime = Math.max(releaseBase, Math.min(this.model === 'snes_ish' ? 0.22 : 0.12, duration * 0.3));
envelope.gain.setValueAtTime(0, when);
envelope.gain.linearRampToValueAtTime(gainValue, when + attackTime);
envelope.gain.setValueAtTime(gainValue, when + Math.max(attackTime, duration - releaseTime));
envelope.gain.exponentialRampToValueAtTime(0.001, when + duration + releaseTime);
osc.start(when);
osc.stop(when + duration + releaseTime + 0.01);
this.activeVoiceCount++;
setTimeout(() => {
try {
osc.disconnect();
envelope.disconnect();
} catch {}
this.activeVoiceCount = Math.max(0, this.activeVoiceCount - 1);
}, (duration + releaseTime + 0.1) * 1000);
}
private scheduleChord(role: Role, pitches: number[], duration: number, velocity: number, when: number): void {
const layer = this.layers.get(role);
if (!layer) return;
if (this.activeVoiceCount >= this.maxVoices) return;
const chordPitches = this.model === 'snes_ish' ? pitches.slice(0, 4) : pitches.slice(0, 3);
for (const pitch of chordPitches) {
if (this.activeVoiceCount >= this.maxVoices) break;
const osc = this.audioContext.createOscillator();
const envelope = this.audioContext.createGain();
osc.frequency.value = this.midiToFrequency(pitch);
if (this.model === 'snes_ish') {
if (role === 'bass') osc.type = 'triangle';
else if (role === 'melody') osc.type = 'sawtooth';
else if (role === 'drone') osc.type = 'sawtooth';
else if (role === 'ostinato') osc.type = 'triangle';
else osc.type = 'sine';
osc.detune.value = (Math.random() - 0.5) * 8;
} else {
if (role === 'bass') osc.type = 'square';
else if (role === 'drone') osc.type = 'sawtooth';
else if (role === 'ostinato') osc.type = 'triangle';
else if (role === 'melody') osc.type = 'triangle';
else osc.type = 'sine';
}
osc.connect(envelope);
envelope.connect(layer.filterNode);
const gainValue = (velocity * 0.3) / Math.max(chordPitches.length * 0.5, 1);
const attackBase = this.model === 'snes_ish' ? 0.01 : 0.005;
const releaseBase = this.model === 'snes_ish' ? 0.16 : 0.01;
const attackTime = Math.max(attackBase, Math.min(0.06, duration * 0.1));
const releaseTime = Math.max(releaseBase, Math.min(this.model === 'snes_ish' ? 0.24 : 0.12, duration * 0.3));
envelope.gain.setValueAtTime(0, when);
envelope.gain.linearRampToValueAtTime(gainValue, when + attackTime);
envelope.gain.setValueAtTime(gainValue, when + Math.max(attackTime, duration - releaseTime));
envelope.gain.exponentialRampToValueAtTime(0.001, when + duration + releaseTime);
osc.start(when);
osc.stop(when + duration + releaseTime + 0.01);
this.activeVoiceCount++;
setTimeout(() => {
try {
osc.disconnect();
envelope.disconnect();
} catch {}
this.activeVoiceCount = Math.max(0, this.activeVoiceCount - 1);
}, (duration + releaseTime + 0.1) * 1000);
}
}
private fadeOutAllLayers(): void {
const when = this.audioContext.currentTime;
for (const layer of this.layers.values()) {
layer.gainNode.gain.linearRampToValueAtTime(0, when + this.fadeTime);
}
setTimeout(() => this.cleanupLayers(), this.fadeTime * 1000 + 100);
}
private cleanupLayers(): void {
for (const layer of this.layers.values()) {
for (const osc of layer.oscillators) {
try {
osc.stop();
osc.disconnect();
} catch {}
}
try { layer.gainNode.disconnect(); } catch {}
try { layer.filterNode.disconnect(); } catch {}
}
this.layers.clear();
this.roleAssignments.clear();
this.nextEventIndex.clear();
}
}
src/types/index.ts
-3
View File
@@ -38,9 +38,6 @@ export interface StructuralFeatures {
export type Role = 'bass' | 'drone' | 'ostinato' | 'texture' | 'accents' | 'melody';
// Procedural synth model presets (test page uses these)
export type SynthModel = 'pre8bit' | 'nes_gb' | 'snes_ish';
export interface RoleAssignment {
role: Role;
sourceTrack: number;