New "Modular" engine in a-immersive with three hot-swappable Faust
sub-engines (subtractive/additive/fm) sharing a common modulation pool:
16 ADSR slots + 32 LFO slots (single-knob sine->tri->square->saw
wavemorph) routed through a 48-source x 10-destination matrix per
engine. Per-connection scalar amounts in [-1, 1], summed at each
destination. Default MLP output count is 512 (32 mod-source params +
480 matrix cells); model reinits on sub-engine swap, count change, or
engine-param exposure toggle.
Faust layer:
- mod-pool.lib: shared ADSR/LFO/source-bus library
- gen-modular-dsp.py: byte-reproducible generator (source of truth)
- modular-subtractive: faithful Minimoog (3 osc, ladder filter, no envs)
- modular-additive: 64-partial, spectral shape + formants, no envs/LFOs
- modular-fm: 4-op matrix + self-feedback, no envs
- All three share d08=amp, d09=pan conventions
- MODULAR_DESTINATIONS.md: authoritative destination table
JS layer:
- ModularEngine: self-contained SynthEngine with getState/setState,
setSubEngine, setModSourceCount, setExposeEngineParam
- modular-ui: drawer with sub-engine toggle, ADSR/LFO count steppers,
per-slot enable switches, matrix grid editor (tap-cycle, long-press
precise, right-click menu, negative amounts), preset overlay
- modular-presets: 6 named presets (Slow pad, Plucky bass, Crystal,
DX bell, Morphing drone + default)
- a-app.js: Modular mode registered, paramMeta:change -> resizeMLP,
modular DSP state persisted under modularDspState, window.__nisps
debug hooks for programmatic control
Tests: tests/e2e/modular-mode.spec.js (11 Playwright tests, all passing
including DSP state survives reload, sub-engine swap keeps paramCount,
preset apply verification).
Also fixes a pre-existing build.sh bug where the -e flag caused faust
to overwrite .wasm outputs with expanded DSP source text, leaving
additive/fm-matrix/eoc-* committed as invalid WebAssembly. Rebuilt all
affected engines with the corrected script. Added an early-message
buffer to faust-worklet-processor.js so setParam calls arriving before
wasm instantiation are queued rather than dropped (needed when the user
configures modular state before clicking Start Audio).
Resolved conflicts: merged all 6 module imports in eoc-chain-ui.js and index.js.
All moduleFactory cases now return real Faust WASM implementations — no stubs remain.
Faust DSP sources, compiled WASM + JSON descriptors, AudioWorklet processors,
and EOCModule subclasses for all three effects.
- meml-4b4: 4-band parametric EQ (fi.low_shelf, fi.peak_eq × 2, fi.high_shelf)
10 params: freq/gain per band, Q for the two mid bell bands
- meml-cpe: stereo feed-forward compressor (co.compressor_mono × 2)
7 params: threshold, ratio, attack, release, knee, makeup, mix (parallel)
- meml-wwc: zita reverb (re.zita_rev1_stereo) with pre-delay and M/S width
8 active params + mod_rate placeholder (zita internal mod not yet exposed)
All three DSPs compile cleanly under Faust 2.83.1. moduleFactory in
eoc-chain-ui.js now returns real instances for eq/compressor/reverb.
Adds the Faust DSP toolchain infrastructure: placeholder additive and FM DSP
files, build.sh (faust -lang wasm per .dsp), faustJsonToParamMeta() to convert
Faust JSON UI trees into the standard paramMeta format, FaustEngineBase
(SynthEngine subclass wiring init/setParam/noteOn/noteOff through AudioWorklet
messages), and FaustWorkletProcessor base class for concrete engine processors.
