MSS_API_MATRIX.md

Miles Sound System (MSS) API Support Matrix

This matrix tracks the availability of major API groups across different historical versions of MSS and the current implementation status in OpenMiles.

Export ABI: every -Dmss-version build (v3–v9) reproduces its reference mss32.dll's decorated export table with zero missing exports. The "OpenMiles" column below tracks behaviour, not symbol presence — every symbol is present.

Support Legend

• 🟢 Full: Functionally implemented and verified.
• 🟡 Partial: Implemented as a functional prototype or stub with basic logic.
• 🔴 None: Not implemented or relevant.
• ⚪ Stub: Symbol exists for binary compatibility but performs no logic.

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1. Core System APIs

Function Group	Intro	AIL v2	MSS v3	MSS 6.6	OpenMiles	Notes
Basic Init (startup, shutdown)	v3	🔴	🟢	🟢	🟢 Full	rebranded in v3.
Legacy Driver Init (install_driver)	v2	🟢	🟢	⚪	⚪ Stub	Used in AIL era.
Error Handling (last_error)	v3	🔴	🟢	🟢	🟢 Full
Preference Management	v4	🔴	🔴	🟢	🟢 Full
Redist Handling (redist_dir)	v6	🔴	🔴	🟢	🟢 Full	Stores path and scans for .asi/.m3d/.flt plugins
Timer API	v3	🔴	🟢	🟢	🟢 Full	Background timer threads
Quick API	v4	🔴	🔴	🟢	🟢 Full	High-level sound engine helpers
Memory API	v4	🔴	🔴	🟢	🟢 Full	Basic memory allocators and locking

2. Digital Audio (Samples & Streams)

Function Group	Intro	AIL v2	MSS v3	MSS 6.6	OpenMiles	Notes
DIG_ Prefix Functions	v2	🟢	🟢	⚪	🔴 None	Aliases not yet exported
AIL_ Prefix Functions	v3	🔴	🟢	🟢	🟢 Full
Sample Allocation/Release	v2	🟢	🟢	🟢	🟢 Full
Volume / Panning Control	v2	🟢	🟢	🟢	🟢 Full
Memory Image Loading	v3	🔴	🟢	🟢	🟢 Full
Streaming (File-based)	v4	🔴	🔴	🟢	🟢 Full
Input API	v4	🔴	🔴	🟢	🟢 Full	Recording via miniaudio capture device
Compression API	v4	🔴	🔴	🟢	🟡 Partial	Decompression implemented
Filter API	v6	🔴	🔴	🟢	🟢 Full	Low-pass filter via miniaudio ma_lpf_node; real-time cutoff/order control

3. 3D Positional Audio

Function Group	Intro	AIL v2	MSS v3	MSS 6.6	OpenMiles	Notes
3D Sample Handle Mgmt	v6	🔴	🔴	🟢	🟢 Full	Allocates Sample3D; file loading via miniaudio
Object Position/Velocity	v6	🔴	🔴	🟢	🟢 Full	Sample3D and listener position/velocity/orientation via miniaudio
3D Providers (EAX, A3D)	v5	🔴	🔴	🟢	🟢 Full	Returns built-in OpenMiles Software 3D provider

4. MIDI & XMIDI

Function Group	Intro	AIL v2	MSS v3	MSS 6.6	OpenMiles	Notes
MDI_ Prefix Functions	v2	🟢	🟢	⚪	🔴 None	Aliases not yet exported
XMIDI Branching	v2	🟢	🟢	🟢	🟢 Full	Tempo fade, position seek with channel state replay
DLS / SF2 Loading	v4	🔴	🔴	🟢	🟢 Full

5. RIB (RAD Interface Broker)

Function Group	Intro	AIL v2	MSS v3	MSS 6.6	OpenMiles	Notes
Provider Infrastructure	v4	🔴	🔴	🟢	🟢 Full
Provider Enumeration	v6	🔴	🔴	🟢	🟢 Full	Real provider enumeration with interface matching

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6. CD Audio

Function Group	Intro	AIL v2	MSS v3	MSS 6.6	OpenMiles	Notes
Redbook Audio	v3	🔴	🟢	🟢	🟡 Partial	Emulated handle tracks play/pause state; no actual CD audio (games fall back gracefully)

7. Event System & SoundBanks (v8/v9)

Function Group	Intro	MSS v6.6	MSS v8	MSS v9	OpenMiles	Notes
Event text constructor/decoder	v8	🔴	🟢	🟢	🟢 Full	Byte-faithful encode + decode for every step type; EVENT_STEP_INFO layout matches the SDK
Event variables (MilesGet/SetVar)	v9	🔴	🔴	🟢	🟢 Full	Per-system variable store
SoundBank load + asset query	v8	🔴	🟢	🟢	🟢 Full	BANK loader; asset enumeration + event-bytecode lookup
Event execution VM (enqueue → instance bookkeeping)	v8	🔴	🟢	🟢	🟡 Partial	Events parse into tracked sound instances (lifecycle, durations, label filtering/caps, event-length, cache/persist counts); audio output of those instances is not yet routed through the mixer

Technical Summary

OpenMiles reproduces the export ABI of every MSS release from v3 through v9 (zero missing decorated exports per version, including per-version arity quirks). Behaviourally, the digital/MIDI/3D/RIB/filter/timer/quick subsystems, the v8/v9 event-text and soundbank layers, and the event execution VM's bookkeeping (enqueue → tracked sound instances with durations, label filtering, per-label caps, event-length, cache/persist accounting) are functional. The main remaining gap is routing event-driven sound instances through the miniaudio mixer (actual audio output) and applying ramp/blend/LFO to live volume/pitch. Legacy DIG_ and MDI_ prefix aliases are not currently exported but could be added as PE export aliases if needed for older titles.

Legacy Compatibility Features:

• AIL_waveOutOpen, AIL_midiOutOpen for games that use older waveOut-style initialization.
• AIL_open_XMIDI_driver / AIL_close_XMIDI_driver as aliases for the MIDI driver functions.