Author Topic: .43 Bidi Loop Error  (Read 6743 times)

Offline Saga Musix

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.43 Bidi Loop Error
« on: August 07, 2006, 15:03:34 »
Hello, i hope i post this error correctly :)
however, i saw this bug even in the old modplug tracker, but not in any other trackers, and it seems that it's not a "feature".

A channel like the following one will only play the last view milliseconds of a sample with bidi loop
Code: [Select]

C-5 1
... 1
... 1
... 1
... 1
... 1
... 1


this error doesn't occur with normal looped samples.
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Offline rewbs

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.43 Bidi Loop Error
« Reply #1 on: August 14, 2006, 01:02:01 »
Ah yes it looks like the bidi loop changes direction whenever a row with the instrument number alone is reached in IT mode (does not happen with XM).

I know you mentioned you haven't seen this in other players, but can you confirm OpenMPT's behaviour is different from the original Impulse Tracker (just to be sure)?

Thanks for reporting this.

Offline Saga Musix

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.43 Bidi Loop Error
« Reply #2 on: August 18, 2006, 19:21:04 »
i'd say yes, IT plays it on the other way...
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Offline LPChip

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.43 Bidi Loop Error
« Reply #3 on: September 13, 2006, 21:46:28 »
Bumping old bugs...
"Heh, maybe I should've joined the compo only because it would've meant I wouldn't have had to worry about a damn EQ or compressor for a change. " - Atlantis
"yes.. I think in this case it was wishful thinking: MPT is makng my life hard so it must be wrong" - Rewbs

Offline Saga Musix

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.43 Bidi Loop Error
« Reply #4 on: January 21, 2007, 15:25:03 »
Quote from: "LPChip"
Bumping old bugs...


They have to be fixed sometime... :D
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Offline LPChip

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.43 Bidi Loop Error
« Reply #5 on: August 14, 2007, 20:56:27 »
Bumping old bugs
"Heh, maybe I should've joined the compo only because it would've meant I wouldn't have had to worry about a damn EQ or compressor for a change. " - Atlantis
"yes.. I think in this case it was wishful thinking: MPT is makng my life hard so it must be wrong" - Rewbs

Offline Saga Musix

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.43 Bidi Loop Error
« Reply #6 on: March 29, 2008, 21:01:45 »
it does still not work as expected.
see here: ----
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Offline Relabsoluness

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.43 Bidi Loop Error
« Reply #7 on: March 29, 2008, 21:07:59 »
Quote from: "Jojo"
it does still not work as expected.
see here: ---

It's supposed to be fixed only when enabling the 'Various playback changes for IT compatibility'-flag in song properties.

Offline Saga Musix

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.43 Bidi Loop Error
« Reply #8 on: March 29, 2008, 21:22:22 »
Okay, it works if i set that flag. But isn't that quite restrictive? i mean, i still want to do those awesome effects like this one in new modules! :)
Code: [Select]
ModPlug Tracker  IT
|C-501...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
|...01...D08
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Offline Relabsoluness

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.43 Bidi Loop Error
« Reply #9 on: March 29, 2008, 22:05:27 »
Quote from: "Jojo"
Okay, it works if i set that flag. But isn't that quite restrictive? i mean, i still want to do those awesome effects like this one in new modules! :)

Sorry, I don't understand the relation - what the use of the flag restricts?

Offline Saga Musix

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.43 Bidi Loop Error
« Reply #10 on: March 29, 2008, 22:13:53 »
Well, if you create a new module, you normally expect that it's using working features and not quirks. In my opinion, the bidi loop error is a quirk and should not be used in standard mode at all. ;)
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Offline Relabsoluness

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.43 Bidi Loop Error
« Reply #11 on: March 29, 2008, 22:27:54 »
Quote from: "Jojo"
Well, if you create a new module, you normally expect that it's using working features and not quirks. In my opinion, the bidi loop error is a quirk and should not be used in standard mode at all. ;)

I think this is just the kind of issue that must be consired when doing actual releases, not just test or development builds. Why that has been set behind the flag is that all mods created with MPT are build with this "erroneous" bidi loop behavior and many of those may sound completely wrong when played with this "fixed" behavior. If the bidi loop behavior is changed, then all ITs created with newer OMPT version would by default play differently in earlier OMPT versions.

Offline Saga Musix

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.43 Bidi Loop Error
« Reply #12 on: March 29, 2008, 23:16:17 »
I honestly think that noone has every made use of this erroneous behaviour. It least I avoided it like hell... Probably other people should give their opinions here as well?
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