Why vol col commands are limited to 0-9 ?

[Paul Legovitch]

Hi, apart from vol and pan, the effects available in the volume column have a limited range (from 00 to 09), why is that ?
I'm particularly interested in the offset effect to combine it with other effects, but it seems to trigger a bigger amount of offset than the equivalent command in the effect column.
What is it based on, and again why is it limited to 9 possible values ?

[Saga Musix]

[irony]
I'm not sure if it works out, but I could try to arrange an interview with Jeff Lim for you, if you really want to know!
[/irony]
It makes sense in a way because IT's volcol is decimal (in contrast to FT2's volcol, which is hex, so the extended effects have a range from 0 to F there). As you might or might not know, MPT was (one of) the first (?) trackers to actutally split the volcol effect letter from the effect value, so it looks weird, but in IT and FT2, the entire volcol is just two letters "wide", so you don't have "F09" there, but F9.

EDIT: The offset command (which is a MPT extension, and should therefore not be used in IT format) multiplies all numbers by 8, meaning that o4 is equivalent to O20.

[Paul Legovitch]

Thanks for the quick reply !
What I don't get is why v and p has 64 possible values and o (and others) only 9. Especially if offset is an MPT extension, it should not be limited... ?
Anyway thanks for the info.
As a side note, I tend to use the IT format with all the new "forbidden" stuff before I eventually convert the song to mptm if I want to use sequences.

[Saga Musix]

Thanks for the quick reply !
What I don't get is why v and p has 64 possible values and o (and others) only 9.

historical and pratical reasons. st3 had a volume column reaching from 0 to 64, and it only supported this command (hence the name in all later trackers). IT1 (which was inspired by st3) then added the panning command with the same range. with those two commands, already more than half of the possible states of a byte (256) were covered, so adding more commands in IT2 with the same granularity was impossible. and as i said, the first letter of the command is actually the effect letter, so it was only possible to use the last letter of the volcol for effect value. To keep things simple (and because only very few volume column byte values are left), the same restrictions apply to the o command. And that is not going to change in the near future.

[Paul Legovitch]

with those two commands, already more than half of the possible states of a byte (256) were coverered, so adding more commands in IT2 with the same granularity was impossible

Now I get it, thanks. I need to change that in my param editor.

And that is not going to change in the near future.

Roger that !