Amiga "StarTrekker" MOD format, by Bjorn Wessen (aka "Star Tracker" in english)
"FLT4" sig version = same as "M.K." Amiga NoiseTracker files.
"FLT8" sig ver = same as "M!K!" Amiga ProTracker files but with 8 channels.
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From "GUSTRACK.DOC" of gustr103.zip (IBM GusTrack v1.03by EJ Botterman jr):
File Formats:
GusTrack will read 4 track ProTracker files and also Star Tracker files.
( ID's M.K. and FLT4 )
And it will read 8 Track Mod files made with Tritons Fast Tracker the
Star Tracker or the Octalyzer.
( ID's 8CHN, FLT8 and OCTA)
( Does anyone know if the FLT8 format really excists ?)
[EJ's Fido Address: 2:285/306.4 (Multi-Byte BBS)]
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Version of StarTrekker as of 1991:
StarTrekker v1.2
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From Stefan Danes :
>StarTrekker 4 & 8 channel
Synth Format: No info, only that it uses 'EXO4' and 'EXO8' as ID strings
Mod Format:
4 Channels. FileFormat is identical to the original 4 Channel, 31 Samples
mod format by Mahony & Kaktus, but uses 'FLT4' as ID string instead of 'M.K.'
8 Channel 'FLT8': Like in 'FLT4' but: Divide all patterns in the orderlist
by 2, and each pattern has an additional 400h bytes:
Normal 4 channel Pattern 400h bytes:
Ch1,Ch2,Ch3,Ch4 [Row 00h]
... [Row ...]
Ch1,Ch2,Ch3,Ch4 [Row 3Fh]
Additional 400h bytes for 'FLT8':
Ch5,Ch6,Ch7,Ch8 [Row 00h]
... [Row ...]
Ch5,Ch6,Ch7,Ch8 [Row 3Fh]
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From Bjoern Wesen :
(Text below written in Nov, 1993)
Hi. You asked for the formats for >6 channel modules. since i wrote
StarTrekker, I can describe its 8 channel format. its very simple. just take
two 4 channel patterns together! So pattern 0 and 1 is one 8 channel pattern.
...
At the same place in the module as the M.K., there is a FLT8 instead if
its a 8 channel startrekker module. Startrekker itself is kinda outdated,
so I would advise you to skip supporting it.
...
First, since the amiga is not an 8 channel computer, I would
not recommend ANY 8 channel format. At least on a 68000, the realtime
mixing does not sound very good, and there's little time for doing effects.
So, in answer to your question of ProTracker compatibility, I'd say nope.
You see, StarTrekker came just after NoiseTracker (me being a good friend
to Mahoney and Kaktus) that is BEFORE protracker.
As for the mixing... Basically I use a buffer, which is so long and plays
at the right speed to make the buffer sound for 1/50 second. So while
the buffer plays I calculate the next buffer. That way the processor dont
have to be timed. If you have a speedier processor you could calculate with
quadruple or more accuracy, say you conneyct a 16bit D/A on the pararllell
port or something, then you could play 8 16bit channels on 44khz.
However all this boils down to composing only. For games and demos, where
the music is REALLY used, you cant afford having the processor calculate
the music half the time.
For the mixing of the buffer, I have a separate buffer for each of the 4
native channels. So I mix two channels into one, by simply sliding
through the two samples, picking the right samples for the speed the
sample should be played in, adding them, scaling the result and putting
into the buffer. You COULD interpolate also to get even better result but
then you need again a speedier processor.
(Text below written in March, 1994)
In regards of the Amiga StarTrekker format:
Since I wrote StarTrekker (once upon a time...) I think I may know the format.
The format you are looking for is FLT8, and the ONLY two differences are:
It says FLT8 instead of FLT4 or M.K., AND, the patterns are PAIRED. I thought
this was the easiest 8 track format possible, since it can be loaded in a
normal 4 channel tracker if you should want to rip sounds or patterns. So,
in a 8 track FLT8 module, patterns 00 and 01 is "really" pattern 00. Patterns
02 and 03 together is "really" pattern 01. Thats it. Oh well, I didnt have the
time to implement all effect commands either, so some FLT8 modules would play
back badly (I think especially the portamento command uses a different "scale"
than the normal portamento command, that would be hard to patch).
See ya...
/Bjorn Wesen (Exolon of FairLight)
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