libxm

A small XM (FastTracker II Extended Module) player library. Designed for easy integration in demos and such, and provides timing functions for easy sync (well, not yet, but it's planned).

Written in C11 and released under the WTFPL license, version 2.

Examples

Three example programs are provided.

xmtoau will play a module and output a .au file to standard output. Example usages:
- Directly play a module (requires the sox package):
```
./xmtoau my_module.xm | play -
```
- Convert the data to a .wav file on the fly, then play it with mplayer:
```
./xmtoau my_module.xm | ffmpeg -i - file.wav
mplayer file.wav
```
xmtoalsa is a simple player that uses the ALSA library. It produces xmp-like output while playing. Use xmtoalsa --help (or check the source) to see the full usage.
xmbench is a benchmark program.

Here are some interesting modules, most showcase unusual or advanced tracking techniques (and thus are a good indicator of a player's accuracy):

Status

Effects

 Status |##| Eff | Info | Description
--------+--+-----+------+------------------------------
DONE    |00|  0  |      | Arpeggio
DONE    |01|  1  |  (*) | Porta up
DONE    |02|  2  |  (*) | Porta down
DONE    |03|  3  |  (*) | Tone porta
DONE    |04|  4  |  (*) | Vibrato
DONE    |05|  5  |  (*) | Tone porta+Volume slide
DONE    |06|  6  |  (*) | Vibrato+Volume slide
DONE    |07|  7  |  (*) | Tremolo
DONE    |08|  8  |      | Set panning
DONE    |09|  9  |      | Sample offset
DONE    |10|  A  |  (*) | Volume slide
DONE    |11|  B  |      | Position jump
DONE    |12|  C  |      | Set volume
DONE    |13|  D  |      | Pattern break
DONE    |14|  E1 |  (*) | Fine porta up
DONE    |--|  E2 |  (*) | Fine porta down
        |--|  E3 |      | Set gliss control
UNTESTED|--|  E4 |      | Set vibrato control
DONE    |--|  E5 |      | Set finetune
DONE    |--|  E6 |      | Set loop begin/loop
UNTESTED|--|  E7 |      | Set tremolo control
DONE    |--|  E9 |      | Retrig note
DONE    |--|  EA |  (*) | Fine volume slide up
DONE    |--|  EB |  (*) | Fine volume slide down
DONE    |--|  EC |      | Note cut
DONE    |--|  ED |      | Note delay
DONE    |--|  EE |      | Pattern delay
DONE    |15|  F  |      | Set tempo/BPM
DONE    |16|  G  |      | Set global volume
DONE    |17|  H  |  (*) | Global volume slide
DONE    |20|  K  |      | Key off              (Also note number 97)
DONE    |21|  L  |      | Set envelope position
DONE    |25|  P  |  (*) | Panning slide
DONE    |27|  R  |  (*) | Multi retrig note
DONE    |29|  T  |  (*) | Tremor
DONE    |33|  X1 |  (*) | Extra fine porta up
DONE    |--|  X2 |  (*) | Extra fine porta down

Volume effects

 Status |  Value  | Meaning
--------+---------+-----------------------------
DONE    | $10-$50 | Set volume (Value-$10)
DONE    | $60-$6f | Volume slide down
DONE    | $70-$7f | Volume slide up
DONE    | $80-$8f | Fine volume slide down
DONE    | $90-$9f | Fine volume slide up
DONE    | $a0-$af | Set vibrato speed
DONE    | $b0-$bf | Vibrato
DONE    | $c0-$cf | Set panning
DONE    | $d0-$df | Panning slide left
DONE    | $e0-$ef | Panning slide right
DONE    | $f0-$ff | Tone porta

Known issues

Only loads FastTracker II-compatible XM files.
Loading a bogus file (that yet has a valid 60-byte header) will probably result in a segmentation fault.
Big endian architectures are not yet supported.

Tests

Some test XM files are in the tests directory. Their goal is to test a certain feature against regressions. A summary of tests (and what they are supposed to test) is in the table below.

     Test     |     Status     |     Tested against     | Extras
--------------+----------------+------------------------+------------------------------------------------
ramping.xm    | PASS           | MilkyTracker           | If XM_RAMPING is ON, no loud clicks should be heard.
ramping2.xm   | PASS           | MilkyTracker           | If XM_RAMPING is ON, no loud clicks should be heard.
tremolo.xm    | PASS           | MilkyTracker           | Should sound identical.
vibrato.xm    | PASS           | MilkyTracker           | Should sound identical.
tremor.xm     | PASS           | MilkyTracker           | Should sound identical.
amiga.xm      | FAIL           | MilkyTracker, xmp      | Should sound identical.
pattern-lo….xm| PASS           | MilkyTracker           | Should play the same notes at the same time.
finetune.xm   | PASS           | MilkyTracker           | Left and right channels should sound identical.

Thanks

Thanks to:

Thunder kurttt@sfu.ca, for writing the modfil10.txt file;
Matti "ccr" Hamalainen ccr@tnsp.org, for writing the xm-form.txt file;
Mr.H of Triton and Guru and Alfred of Sahara Surfers, for writing the specification of XM 1.04 files;
All the MilkyTracker contributors, for the thorough documentation of effects.
All the people that helped on #milkytracker IRC.

Justasic / libxm