reaper-control/.sdd/changes/section-energy/tasks.md

Tasks: Section Energy Curve

Phase 1: Schema + Foundation

• 1.1 Add vol_mult: float = 1.0 field to ClipDef in src/core/schema.py
• 1.2 Add TRACK_ACTIVITY dict and _section_active() helper to scripts/compose.py
• 1.3 Add SECTION_MULTIPLIERS dict and update build_section_structure() to set velocity_mult and vol_mult per section type
• 1.4 Rename build → pre-chorus in SECTIONS and DRUMLOOP_ASSIGNMENTS in scripts/compose.py

Phase 2: Builder Refactor

• 2.1 Refactor build_drumloop_track() — use _section_active() instead of DRUMLOOP_ASSIGNMENTS dict lookup
• 2.2 Refactor build_perc_track() — replace if section.name in (...) with _section_active()
• 2.3 Refactor build_bass_track() — replace section.energy with section.velocity_mult for velocity calc
• 2.4 Refactor build_chords_track() — use _section_active() for section check, velocity_mult for velocity
• 2.5 Refactor build_lead_track() — use _section_active() for section check, velocity_mult for velocity
• 2.6 Refactor build_clap_track() — use _section_active() instead of section.name.startswith(...)
• 2.7 Refactor build_pad_track() — use _section_active() for section check, velocity_mult for velocity

Phase 3: RPPBuilder D_VOL Emission

• 3.1 Update _build_clip() in src/reaper_builder/__init__.py to emit D_VOL when clip.vol_mult != 1.0 and clip is audio
• 3.2 Update _build_midi_source() to scale notes by clip.vol_mult (post-processing fallback)

Phase 4: Tests

• 4.1 Add test_build_section_structure_sets_multipliers to tests/test_section_builder.py — verify per-section velocity_mult/vol_mult
• 4.2 Add test_section_active_helper — edge cases: unknown section, unknown role, all known combos
• 4.3 Add test_clipdef_vol_mult_default to tests/test_core_schema.py
• 4.4 Add test_dvol_emission to tests/test_reaper_builder.py — audio clip vol_mult≠1.0 emits D_VOL, default vol_mult=1.0 does not
• 4.5 Update test_compose_integration.py — verify sparse intro (no bass/chords/lead) vs dense chorus, section rename
• 4.6 Run full test suite (167 tests) — 161 pass, 6 pre-existing failures in test_chords.py (unrelated)