Author Topic: Gxx... bug?  (Read 6190 times)

Offline Louigi Verona

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Gxx... bug?
« on: November 28, 2005, 07:41:59 »
I have come upon an interesting... thing. In MPT this weekend.

Here's the situation.
In one channel I have a lead that uses a Gxx effect. For example, a G07 works fine and I like the way it goes.
Then I copy paste the notes into the second channel with some delay to produce an echo.

But in the second 'echo' channel the Gxx function doesn't work properly! And I have to change it to, say, G08 to get the same effect!

How can that be possible?

Offline rewbs

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Re: Gxx... bug?
« Reply #1 on: November 28, 2005, 09:59:25 »
Quote from: "Louigi Verona"
But in the second 'echo' channel the Gxx function doesn't work properly! And I have to change it to, say, G08 to get the same effect!


The behaviour of Gxx is dependant on the number of ticks per row. Are the ticks per row / speed the same where G07 and G08 are being played?

Offline Louigi Verona

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Gxx... bug?
« Reply #2 on: November 28, 2005, 10:00:49 »
everything is the same - it is the very column, just delayed a couple of rows to produce an echo effect - so the only difference is lower volume set.

Offline rewbs

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Gxx... bug?
« Reply #3 on: November 28, 2005, 10:07:45 »
Quote from: "Louigi Verona"
everything is the same - it is the very column, just delayed a couple of rows to produce an echo effect - so the only difference is lower volume set.


Could you make a simple example available for download?

Offline Louigi Verona

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Gxx... bug?
« Reply #4 on: November 28, 2005, 12:50:33 »
during these weekends I almost finished a track. I'll fix some minor things and release it - there you will see an example, I'll tell you which pattern.

Offline rewbs

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Gxx... bug?
« Reply #5 on: November 28, 2005, 13:10:47 »
OK. Note that in general it's easier for developers to work with the most simple testcase that displays the bug (if you have time to provide it), rather than a fully-fledged track.

Offline Louigi Verona

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Gxx... bug?
« Reply #6 on: December 05, 2005, 09:52:58 »
Okay, here's the track. Look closely into, say, pattern 7. The lead theme is played and in the next channel an echo. Note that Gxx effects applied are different, yet everything is the same but the volumes. How can that be possible?

http://www.dimlight.net/music/louigi/storyteller.zip

Offline rewbs

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Re: Gxx... bug?
« Reply #7 on: December 05, 2005, 10:09:42 »
Quote from: "Louigi Verona"
Quote from: "rewbs"
Quote from: "Louigi Verona"
But in the second 'echo' channel the Gxx function doesn't work properly! And I have to change it to, say, G08 to get the same effect!


The behaviour of Gxx is dependant on the number of ticks per row. Are the ticks per row / speed the same where G07 and G08 are being played?


everything is the same - it is the very column, just delayed a couple of rows to produce an echo effect - so the only difference is lower volume set.


Actually you are shuffling the ticks per row (A07/A05/A07/A05...). The lead and echo are 3 rows apart, so when the lead Gxx falls on an A07 row, the echo falls on an A05 row, which explains the difference. "Gxx" basically means slide the pitch by xx per tick, so the Ayy has an impact.

Offline Louigi Verona

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Gxx... bug?
« Reply #8 on: December 05, 2005, 11:24:20 »
Quote
Actually you are shuffling the ticks per row (A07/A05/A07/A05...). The lead and echo are 3 rows apart, so when the lead Gxx falls on an A07 row, the echo falls on an A05 row, which explains the difference. "Gxx" basically means slide the pitch by xx per tick, so the Ayy has an impact.


Thank you! That was very educational, I haven't thought about the speed changes!  :)