feat: Add intelligent_dnb, trip_hop, and boom_bap genres

[jhillbht]

Summary

Adds three new genre presets to the PatternGenerator service, each with complete pattern generation, drum patterns, and basslines.

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New Genres

🎵 Intelligent DnB (160-175 BPM)

Style: LTJ Bukem, Good Looking Records, early 90s atmospheric DnB

Element	Implementation
Breaks	Rolling breakbeats using breaks165 from dirt-samples
Bass	Deep sine sub (80Hz LPF) with proper ADSR
Chords	Jazz voicings - minor 9ths, 7ths (Cm9 → Fm9 → Bbm9 → Ebmaj7)
Atmosphere	Rhodes (gm_epiano1), strings (gm_strings)
Effects	Heavy reverb (0.5-0.7), dotted eighth delay (0.375s)

Aliases: liquid_dnb, atmospheric_dnb, bukem, intelligent, liquid, atmospheric

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🌙 Trip Hop (80-100 BPM)

Style: Portishead, Massive Attack, Flying Lotus

Element	Implementation
Drums	Slow, heavy half-time feel with TR808 snares
Bass	Deep sine with longer release (0.8s)
Keys	Dark Rhodes with dotted quarter delay (0.666s)
Atmosphere	Filtered saw pads, vinyl crackle texture
Feel	Moody, dusty, cinematic

Aliases: triphop, portishead, massive_attack, flying_lotus

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💥 Boom Bap (85-100 BPM)

Style: DJ Premier, Alchemist, Daringer, Hit-Boy

Element	Implementation
Drums	Hard-hitting kicks, crispy snares, swing (0.08)
Bass	Punchy sawtooth (180Hz LPF)
Chops	Soul sample-style Rhodes
Stabs	Cinematic strings, horn accents
Feel	Golden era, head-nodding groove

Aliases: boombap, golden_era, premier, alchemist, daringer, hitboy

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Changes

src/services/PatternGenerator.ts

• Added generateIntelligentDnB() method
• Added generateTripHop() method
• Added generateBoomBap() method
• Added interval helper methods (getInterval, getFourth, getFifth, etc.)
• Updated generateDrumPattern() with new genre patterns (3 complexity levels each)
• Updated generateBassline() with new genre basslines
• Updated generateCompletePattern() to route to specialized generators
• Added alias mappings for all genre variations

patterns/examples/

• intelligent-dnb.js - Full atmospheric DnB example (170 BPM, C minor)
• trip-hop.js - Dark trip hop example (90 BPM, D minor)
• boom-bap.js - Golden era hip hop example (92 BPM, E minor)

README.md

• Updated genre lists in tools table
• Added new genres to example patterns section

patterns/examples/README.md

• Added documentation for all three new genres

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Usage Examples

// Intelligent DnB
generateCompletePattern('intelligent_dnb', 'C', 170)
generateCompletePattern('bukem', 'Am', 168)

// Trip Hop
generateCompletePattern('trip_hop', 'D', 90)
generateCompletePattern('portishead', 'Gm', 85)

// Boom Bap
generateCompletePattern('boom_bap', 'E', 92)
generateCompletePattern('premier', 'Am', 94)

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Testing

All patterns tested in strudel.cc and produce valid output.

Related

• Pattern library source: https://github.com/Organized-AI/strudel-intelligent-dnb
• dirt-samples documentation for break samples

[williamzujkowski]

Excellent Contribution! 🎶

First off, thank you for this substantial contribution. The musical implementation is solid:

• Intelligent DnB: Rolling breaks with breaks165, jazz chord voicings (minor 9ths), deep sine sub - classic Bukem style ✅
• Trip Hop: Half-time feel, dusty hats, dark Rhodes with dotted quarter delay - very Portishead ✅
• Boom Bap: Hard-hitting kicks, swing (0.08), soul sample chops - proper golden era vibes ✅

The code quality is good, the alias mappings are comprehensive, and the example patterns are well-crafted.

One Issue: Missing Tests

The build passes, but our coverage thresholds are not met:

Jest: "global" coverage threshold for statements (80%) not met: 68.86%
Jest: "global" coverage threshold for branches (70%) not met: 63.75%

Per our CLAUDE.md coding standards, we require 80% coverage for services.

What's needed: Tests for the new code in PatternGenerator.test.ts. Following the existing test patterns, you'd add:

// In generateDrumPattern tests - add to the styles array:
const styles = ['techno', 'house', 'dnb', ... 'intelligent_dnb', 'trip_hop', 'boom_bap'];

// In generateBassline tests - add to the styles array:
const styles = ['techno', 'house', ... 'intelligent_dnb', 'trip_hop', 'boom_bap'];

// New tests for generateCompletePattern:
test('should generate intelligent_dnb pattern with correct structure', () => {
  const pattern = generator.generateCompletePattern('intelligent_dnb', 'C', 170);
  expect(pattern).toContain('// Intelligent DnB');
  expect(pattern).toContain('setcps(170/60)');
  expect(pattern).toContain('breaks165');
  expect(pattern).toContain('gm_epiano1');
});

// Similar for trip_hop and boom_bap

// Test alias resolution:
test('should resolve genre aliases correctly', () => {
  const liquidDnb = generator.generateCompletePattern('liquid_dnb', 'C', 170);
  const bukem = generator.generateCompletePattern('bukem', 'C', 170);
  expect(liquidDnb).toContain('// Intelligent DnB');
  expect(bukem).toContain('// Intelligent DnB');
});

The new private helper methods (getInterval, getFourth, etc.) are covered indirectly through the generator tests, so those are fine.

Summary

The musical implementation is excellent. Add the tests and this is ready to merge. If you need any help with the test structure or have questions, just ask!

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Looking forward to hearing some intelligent DnB in my Strudel sessions.