Add v2 Game Boy sound engine (isolated from v1)
- Authentic DMG-CPU sound chip implementation: - 4 Pulse channels with duty cycle control (12.5%, 25%, 50%, 75%) - 2 Wave channels with 4-bit wavetables - 2 Noise channels with LFSR (7-bit and 15-bit modes) - GameBoy Colorizer effect chain: - Low-pass filter (natural GB rolloff) - Bit-crushing (4-bit DAC simulation) - Sample rate reduction - Saturation and high-pass filter - Presets: DMG, GBC, GBA, Clean - Intelligent MIDI processing: - Track analysis and role detection (bass, lead, drums, etc.) - Automatic channel mapping to GB channels - Chord arpeggiator for polyphony handling - GameBoy Arranger for fuller sound - BitMidi search integration - Completely isolated from v1 (no changes to src/)
This commit is contained in:
b1rdmania
@@ -0,0 +1,364 @@
|
||||
/**
|
||||
* Channel Mapper
|
||||
*
|
||||
* Intelligently assigns MIDI tracks to the 8 GB channels based on
|
||||
* track analysis results. Prioritizes the most important tracks
|
||||
* and assigns them to the most appropriate channel types.
|
||||
*/
|
||||
|
||||
import { TrackAnalyzer, type MIDITrack } from './TrackAnalyzer';
|
||||
import type {
|
||||
ChannelAssignment,
|
||||
TrackAnalysis,
|
||||
ChannelId,
|
||||
PulseChannelId,
|
||||
WaveChannelId,
|
||||
NoiseChannelId,
|
||||
TrackRole
|
||||
} from '../../types';
|
||||
import type { DutyIndex } from '../synthesis/DutyCycle';
|
||||
import type { WavePreset } from '../synthesis/WaveTable';
|
||||
import type { LFSRMode } from '../synthesis/LFSR';
|
||||
|
||||
/**
|
||||
* Channel mapping configuration
|
||||
*/
|
||||
export interface ChannelMapperConfig {
|
||||
/** Maximum tracks to assign (limits complexity) */
|
||||
maxTracks: number;
|
||||
|
||||
/** Whether to arpeggiate harmony tracks */
|
||||
arpeggiateHarmony: boolean;
|
||||
|
||||
/** Default duty cycle for lead channels */
|
||||
leadDuty: DutyIndex;
|
||||
|
||||
/** Default duty cycle for harmony channels */
|
||||
harmonyDuty: DutyIndex;
|
||||
}
|
||||
|
||||
const DEFAULT_CONFIG: ChannelMapperConfig = {
|
||||
maxTracks: 8,
|
||||
arpeggiateHarmony: true,
|
||||
leadDuty: 2, // 50% for full sound
|
||||
harmonyDuty: 1, // 25% for thinner, less intrusive sound
|
||||
};
|
||||
|
||||
/**
|
||||
* Available channel pools by type
|
||||
*/
|
||||
const CHANNEL_POOLS = {
|
||||
pulse: ['p1', 'p2', 'p3', 'p4'] as PulseChannelId[],
|
||||
wave: ['w1', 'w2'] as WaveChannelId[],
|
||||
noise: ['n1', 'n2'] as NoiseChannelId[],
|
||||
};
|
||||
|
||||
export class ChannelMapper {
|
||||
private analyzer: TrackAnalyzer;
|
||||
private config: ChannelMapperConfig;
|
||||
|
||||
constructor(config: Partial<ChannelMapperConfig> = {}) {
|
||||
this.analyzer = new TrackAnalyzer();
|
||||
this.config = { ...DEFAULT_CONFIG, ...config };
|
||||
}
|
||||
|
||||
/**
|
||||
* Update configuration.
|
||||
*/
|
||||
setConfig(config: Partial<ChannelMapperConfig>): void {
|
||||
this.config = { ...this.config, ...config };
|
||||
}
|
||||
|
||||
/**
|
||||
* Map MIDI tracks to GB channels.
|
||||
* Returns an array of channel assignments.
|
||||
*/
|
||||
mapTracks(tracks: MIDITrack[]): ChannelAssignment[] {
|
||||
// Analyze all tracks
|
||||
const analyses = this.analyzer.analyzeTracks(tracks);
|
||||
|
||||
// Filter out empty tracks
|
||||
const nonEmptyAnalyses = analyses.filter(a => a.noteCount > 0);
|
||||
|
||||
// Track used channels
|
||||
const usedChannels = new Set<ChannelId>();
|
||||
|
||||
// Assign channels in priority order
|
||||
const assignments: ChannelAssignment[] = [];
|
||||
|
||||
for (const analysis of nonEmptyAnalyses) {
|
||||
if (assignments.length >= this.config.maxTracks) break;
|
||||
|
||||
const assignment = this.assignChannel(analysis, usedChannels);
|
||||
if (assignment) {
|
||||
assignments.push(assignment);
|
||||
usedChannels.add(assignment.channelId);
|
||||
}
|
||||
}
|
||||
|
||||
return assignments;
|
||||
}
|
||||
|
||||
/**
|
||||
* Assign a single track to a channel.
|
||||
*/
|
||||
private assignChannel(
|
||||
analysis: TrackAnalysis,
|
||||
usedChannels: Set<ChannelId>
|
||||
): ChannelAssignment | null {
|
||||
const { role, hasChords } = analysis;
|
||||
|
||||
// Route to appropriate channel type based on role
|
||||
switch (role) {
|
||||
case 'drums':
|
||||
return this.assignDrums(analysis, usedChannels);
|
||||
|
||||
case 'bass':
|
||||
return this.assignBass(analysis, usedChannels);
|
||||
|
||||
case 'lead':
|
||||
return this.assignLead(analysis, usedChannels);
|
||||
|
||||
case 'harmony':
|
||||
return this.assignHarmony(analysis, usedChannels, hasChords);
|
||||
|
||||
case 'pad':
|
||||
return this.assignPad(analysis, usedChannels);
|
||||
|
||||
case 'fx':
|
||||
return this.assignFX(analysis, usedChannels);
|
||||
|
||||
default:
|
||||
// Fallback to any available pulse channel
|
||||
return this.assignToAnyPulse(analysis, usedChannels);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Assign drums to noise channels.
|
||||
*/
|
||||
private assignDrums(
|
||||
analysis: TrackAnalysis,
|
||||
usedChannels: Set<ChannelId>
|
||||
): ChannelAssignment | null {
|
||||
// Try noise channels first
|
||||
const channel = this.findFreeChannel(CHANNEL_POOLS.noise, usedChannels);
|
||||
|
||||
if (!channel) return null;
|
||||
|
||||
// Use 7-bit for kick/snare, 15-bit for hihats
|
||||
// Default to 7-bit as it's punchier
|
||||
const noiseMode: LFSRMode = '7bit';
|
||||
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: channel,
|
||||
shouldArpeggiate: false,
|
||||
noiseMode,
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* Assign bass to wave channel.
|
||||
*/
|
||||
private assignBass(
|
||||
analysis: TrackAnalysis,
|
||||
usedChannels: Set<ChannelId>
|
||||
): ChannelAssignment | null {
|
||||
// Prefer w1 for bass
|
||||
if (!usedChannels.has('w1')) {
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: 'w1',
|
||||
shouldArpeggiate: false,
|
||||
wavePreset: 'bass' as WavePreset,
|
||||
};
|
||||
}
|
||||
|
||||
// Fall back to w2
|
||||
if (!usedChannels.has('w2')) {
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: 'w2',
|
||||
shouldArpeggiate: false,
|
||||
wavePreset: 'bass' as WavePreset,
|
||||
};
|
||||
}
|
||||
|
||||
// No wave channels available, try pulse with low duty
|
||||
const pulseChannel = this.findFreeChannel(CHANNEL_POOLS.pulse, usedChannels);
|
||||
if (pulseChannel) {
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: pulseChannel,
|
||||
shouldArpeggiate: false,
|
||||
dutyCycle: 2 as DutyIndex, // 50% for fuller bass
|
||||
};
|
||||
}
|
||||
|
||||
return null;
|
||||
}
|
||||
|
||||
/**
|
||||
* Assign lead melody to pulse channels.
|
||||
*/
|
||||
private assignLead(
|
||||
analysis: TrackAnalysis,
|
||||
usedChannels: Set<ChannelId>
|
||||
): ChannelAssignment | null {
|
||||
// Prefer p1 or p2 (sweep-capable) for lead
|
||||
for (const channelId of ['p1', 'p2'] as PulseChannelId[]) {
|
||||
if (!usedChannels.has(channelId)) {
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId,
|
||||
shouldArpeggiate: false,
|
||||
dutyCycle: this.config.leadDuty,
|
||||
};
|
||||
}
|
||||
}
|
||||
|
||||
// Fall back to p3/p4
|
||||
const channel = this.findFreeChannel(['p3', 'p4'] as PulseChannelId[], usedChannels);
|
||||
if (channel) {
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: channel,
|
||||
shouldArpeggiate: false,
|
||||
dutyCycle: this.config.leadDuty,
|
||||
};
|
||||
}
|
||||
|
||||
return null;
|
||||
}
|
||||
|
||||
/**
|
||||
* Assign harmony to pulse channels (with optional arpeggio).
|
||||
*/
|
||||
private assignHarmony(
|
||||
analysis: TrackAnalysis,
|
||||
usedChannels: Set<ChannelId>,
|
||||
hasChords: boolean
|
||||
): ChannelAssignment | null {
|
||||
// Use p3/p4 for harmony (thinner sound, no sweep)
|
||||
const channel = this.findFreeChannel(['p3', 'p4', 'p1', 'p2'] as PulseChannelId[], usedChannels);
|
||||
|
||||
if (!channel) return null;
|
||||
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: channel,
|
||||
shouldArpeggiate: this.config.arpeggiateHarmony && hasChords,
|
||||
dutyCycle: this.config.harmonyDuty,
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* Assign pad to wave channel.
|
||||
*/
|
||||
private assignPad(
|
||||
analysis: TrackAnalysis,
|
||||
usedChannels: Set<ChannelId>
|
||||
): ChannelAssignment | null {
|
||||
// Prefer w2 for pads
|
||||
if (!usedChannels.has('w2')) {
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: 'w2',
|
||||
shouldArpeggiate: false,
|
||||
wavePreset: 'pad' as WavePreset,
|
||||
};
|
||||
}
|
||||
|
||||
// Fall back to w1
|
||||
if (!usedChannels.has('w1')) {
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: 'w1',
|
||||
shouldArpeggiate: false,
|
||||
wavePreset: 'pad' as WavePreset,
|
||||
};
|
||||
}
|
||||
|
||||
// Fall back to pulse
|
||||
const pulseChannel = this.findFreeChannel(CHANNEL_POOLS.pulse, usedChannels);
|
||||
if (pulseChannel) {
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: pulseChannel,
|
||||
shouldArpeggiate: false,
|
||||
dutyCycle: 2 as DutyIndex,
|
||||
};
|
||||
}
|
||||
|
||||
return null;
|
||||
}
|
||||
|
||||
/**
|
||||
* Assign FX/incidental to any available pulse channel.
|
||||
*/
|
||||
private assignFX(
|
||||
analysis: TrackAnalysis,
|
||||
usedChannels: Set<ChannelId>
|
||||
): ChannelAssignment | null {
|
||||
// FX goes to any available pulse channel
|
||||
const channel = this.findFreeChannel(CHANNEL_POOLS.pulse, usedChannels);
|
||||
|
||||
if (!channel) return null;
|
||||
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: channel,
|
||||
shouldArpeggiate: false,
|
||||
dutyCycle: 0 as DutyIndex, // 12.5% for thin, effects-like sound
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* Assign to any available pulse channel.
|
||||
*/
|
||||
private assignToAnyPulse(
|
||||
analysis: TrackAnalysis,
|
||||
usedChannels: Set<ChannelId>
|
||||
): ChannelAssignment | null {
|
||||
const channel = this.findFreeChannel(CHANNEL_POOLS.pulse, usedChannels);
|
||||
|
||||
if (!channel) return null;
|
||||
|
||||
return {
|
||||
trackIndex: analysis.trackIndex,
|
||||
channelId: channel,
|
||||
shouldArpeggiate: false,
|
||||
dutyCycle: 2 as DutyIndex,
|
||||
};
|
||||
}
|
||||
|
||||
/**
|
||||
* Find the first free channel from a pool.
|
||||
*/
|
||||
private findFreeChannel<T extends ChannelId>(
|
||||
pool: T[],
|
||||
usedChannels: Set<ChannelId>
|
||||
): T | null {
|
||||
for (const channel of pool) {
|
||||
if (!usedChannels.has(channel)) {
|
||||
return channel;
|
||||
}
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
/**
|
||||
* Get the analyzer for external use.
|
||||
*/
|
||||
getAnalyzer(): TrackAnalyzer {
|
||||
return this.analyzer;
|
||||
}
|
||||
|
||||
/**
|
||||
* Analyze tracks without mapping (useful for UI display).
|
||||
*/
|
||||
analyzeTracks(tracks: MIDITrack[]): TrackAnalysis[] {
|
||||
return this.analyzer.analyzeTracks(tracks);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user