mirror of
https://github.com/curioustorvald/tsvm.git
synced 2026-06-06 05:28:31 +09:00
taud Ixmp extension, doc cleanup
This commit is contained in:
minjaesong
@@ -2411,7 +2411,8 @@ TODO:
|
||||
[ ] establish hooks for the interrupts
|
||||
[x] Samples and Instruments view (viewer on taut.js; editor on separate .js)
|
||||
follow the ImpulseTracker design first, then improve from there
|
||||
[ ] Sample desig for instrument in Pitch-Volume space (one rectangle = one patch). If undefined, the old sample pointer falls thru
|
||||
[?] Sample desig for instrument in Pitch-Volume space (one rectangle = one patch). If undefined, the old sample pointer falls thru
|
||||
[ ] Needs .it and .xm test file to complete it2taud and xm2taud
|
||||
|
||||
TODO - list of demo songs that MUST ship with Microtone:
|
||||
* 4THSYM (rename to Fourth Symmetriad) — excellent piece for demonstrating NNAs and filter envelopes
|
||||
@@ -2470,7 +2471,7 @@ Audio Adapter MMIO
|
||||
Write 16 to initialise the MP2 context (call this before the decoding of NEW music)
|
||||
Write 1 to decode the frame as MP2
|
||||
|
||||
Calling with more than one bit set will result in UNDEFINED BEHAVIOUR
|
||||
Calling with more than one bit set will result in UNDEFINED BEHAVIOUR — except for the flag 0x11, in which the hardware must initialise then immediately start decoding.
|
||||
|
||||
41 RO: MP2 Decoder Status
|
||||
Non-zero value indicates the decoder is busy. Different value may indicate different decoder status.
|
||||
@@ -2620,6 +2621,17 @@ This is a file format for Taud tracker data. Taud can be extended with Microtone
|
||||
|
||||
Endianness: Little
|
||||
|
||||
# Conformance language
|
||||
(RFC 2119+8174)
|
||||
- **MUST** / **MUST NOT** / **REQUIRED** / **SHALL** / **SHALL NOT** — absolute requirements / prohibitions. A conforming implementation **SHALL** observe every such rule; an implementation that violates one is non-conforming.
|
||||
- **SHOULD** / **SHOULD NOT** / **RECOMMENDED** / **NOT RECOMMENDED** — strong guidance. An implementation **MAY** deviate in particular circumstances, but the full implications **MUST** be understood and weighed before doing so.
|
||||
- **MAY** / **OPTIONAL** — truly optional. Implementations that include the feature and implementations that omit it are equally conforming, and each **MUST** be prepared to interoperate with the other (with reduced functionality where the optional feature is the means of interoperation).
|
||||
(IMPLEMENTATION DETAILS)
|
||||
- **INVALID.** Blame the encoder; decoder MUST stop decoding with appropriate errors.
|
||||
- **UNDEFINED BEHAVIOUR.** Encoder MAY encode it; decoder MAY do whatever it wants to, including spawning a daemon out of your nose.
|
||||
- **IGNORED.** Encoder MAY encode it; decoder MUST skip past it.
|
||||
- **RESERVED.** Encoder MUST NOT encode it. Decoder MUST skip past it.
|
||||
|
||||
# File Structure
|
||||
\x1F T S V M a u d
|
||||
[HEADER]
|
||||
@@ -2657,7 +2669,7 @@ Endianness: Little
|
||||
Float32 Frequency at the base note. Tracker default is 8363.0. If zero, assume the tracker default
|
||||
Uint8 Flags for Global Behaviour (effect symbol '1')
|
||||
0b 000 rrr ff
|
||||
ff: tone mode (0: linear pitch slides, 1: Amiga period slides, 2: linear-frequency slides, 3: reserved)
|
||||
ff: tone mode (0: linear pitch slides, 1: Amiga period slides, 2: linear-frequency slides, 3: RESERVED)
|
||||
rrr: interpolation mode (0: default, 1: none, 2: Amiga 500, 3: Amiga 1200, 4: SNES 4-tap Gaussian, 5: NES DPCM simulation)
|
||||
Uint8 Song global volume
|
||||
* ImpulseTracker has range of 0..128; multiply by (255/128) then round to int
|
||||
@@ -2665,7 +2677,7 @@ Endianness: Little
|
||||
* ImpulseTracker has range of 0..128; multiply by (255/128) then round to int
|
||||
Uint32 Compressed size of PATTERN BIN for this song
|
||||
Uint32 Compressed size of CUE SHEET for this song
|
||||
Byte[6] Reserved
|
||||
Byte[6] RESERVED
|
||||
|
||||
Taud device can queue up to 2 "playdata" in its buffer, which can be interpreted as a song.
|
||||
|
||||
@@ -2687,7 +2699,7 @@ Endianness: Little
|
||||
Project Data is just a concatenation of blocks identified by their FourCC.
|
||||
|
||||
Byte[8] Magic (\x1E T a u d P r J)
|
||||
Byte[8] Reserved
|
||||
Byte[8] RESERVED
|
||||
* Repetition of
|
||||
Byte[4] Title of the section (fourcc)
|
||||
Uint32 Section length
|
||||
@@ -2738,11 +2750,11 @@ prefixes:
|
||||
* Repetition of:
|
||||
Uint8 Notation index (starting from zero) used by songs
|
||||
Uint32 Size of this notation following this field
|
||||
Uint16 Reserved for flags
|
||||
Uint16 RESERVED for flags
|
||||
Uint16 Interval size in 4096-TET lattice (octave = 0x1000, tritave = 0x195C). If you are not using an interval system (which means you are responsible for defining every note expressible), this must be 0.
|
||||
Uint16 Reserved for float32 interval size (should it be in 4096-TET which is inexact or frequency multiplier which is exact but difficult to implement?)
|
||||
Uint16 RESERVED for float32 interval size (should it be in 4096-TET which is inexact or frequency multiplier which is exact but difficult to implement?)
|
||||
Uint16 Notes between interval (or octave) MINUS ONE; 12-TET will have value 11
|
||||
Byte[8] Reserved
|
||||
Byte[8] RESERVED
|
||||
Byte[*] Name, null terminated. Encoding: UTF-8
|
||||
Byte[*] Notation table. 0xFF-separated and null-terminated. Encoding: Taud charset
|
||||
Uint16[*] Frequency table. Size of the table is defined by "Notes between interval MINUS ONE". This is a lookup table of relative pitch offsets (against the base tuning note) in 4096-TET space. Index zero of this table will be 0x0 if you read the spec right
|
||||
@@ -2763,6 +2775,45 @@ prefixes:
|
||||
Uint8 Version (Ascii 'a')
|
||||
Bytes Notation definitions (see above)
|
||||
|
||||
* Ixmp. Instrument extra samples
|
||||
* Repetition of:
|
||||
Uint8 Instrument ID
|
||||
Uint24 Count of patches
|
||||
** Repetition of:
|
||||
Uint8 Patch definition version (always 1)
|
||||
Uint16 Pitch start ; Taud 4096-TET noteVal (same scale as pattern-cell note)
|
||||
Uint16 Pitch end (inclusive)
|
||||
Uint8 Volume start ; 0..63
|
||||
Uint8 Volume end (inclusive) ; 0..63
|
||||
- Above four parameters define a rectangle over the Pitch-Volume space. See Notes 4 and 5
|
||||
Uint32 Sample pointer
|
||||
Uint16 Sample length
|
||||
Uint16 Play Start (usually 0 but not always)
|
||||
Uint16 Loop Start (can be smaller than Play Start)
|
||||
Uint16 Loop End
|
||||
Uint16 samplingRate ; per-sample C-5 speed; same encoding as base instrument byte 6-7
|
||||
Int16 sampleDetune ; per-sample fine detune in signed 4096-TET units (XM finetune; IT samples leave 0)
|
||||
Uint8 loopMode ; same encoding as base instrument byte 14 (bits 0-1 = mode, bit 2 = sustain loop)
|
||||
Uint8 defaultPan ; per-sample default pan (0..255; 0x80 = centre); 0xFF = "no override"
|
||||
Uint8 defaultNoteVolume ; per-sample default note volume (0..255 scaled from IT 0..64); 0 = "no override"
|
||||
Uint8 vibratoSpeed ; per-sample auto-vibrato (mirrors base inst byte 175)
|
||||
Uint8 vibratoSweep ; per-sample auto-vibrato (mirrors base inst byte 176)
|
||||
Uint8 vibratoDepth ; per-sample auto-vibrato (mirrors base inst byte 187)
|
||||
Uint8 vibratoRate ; per-sample auto-vibrato (mirrors base inst byte 188)
|
||||
Uint8 vibratoWaveform ; bits 0-2 only (mirrors instrumentFlag bits 2-4); 0xFF = "no override"
|
||||
|
||||
Notes:
|
||||
0. this extension is made to support IT/XM instrument spec as well as partial compatibility to SF2 (Soundfont format two)
|
||||
1. Envelopes (vol/pan/pf), fadeout, NNA / DCT / DCA, pitch-pan, filter, IGV and any other "instrument-scope" parameters all follow the base instrument definition. Only sample-scope parameters (the patch fields listed above) override.
|
||||
2. overlapping regions are considered INVALID
|
||||
3. multiple Ixmp blocks pointing the same instrument are considered INVALID
|
||||
4. IT and XM does not define volumes. Keep the Volume rectangle at 0..63 — the engine clamps to that range when matching.
|
||||
5. SF2 does define volumes (because MIDI). Convert it using `round(velocity * (63/127))`
|
||||
On import, `initialAttenuation`, filters and ADSR shall be ignored
|
||||
6. Patch selection at trigger time walks the patch list in order; the first patch whose rectangle contains the trigger's (noteVal, rowVolume) wins. When no patch matches, the base instrument's sample fields are used unchanged.
|
||||
7. Sentinel values listed above ("no override") let a patch defer to the base instrument for a given field — used by converters that don't carry per-sample data for one of the dimensions (e.g. SF2 ignoring per-sample pan).
|
||||
8. Total per-patch payload is 31 bytes.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
**S3M (ScreamTracker 3) to Taud conversion notes**
|
||||
|
||||
Reference in New Issue
Block a user