[PD] vline~ precision, or sequentially segmented playback of a buffer

[João Pais]

Hello list,

continuing with a topic I started some time ago (but couldn't continue the
discussion), I've made a simulated version of my patch to explain the
situation. The full patch is too complex, and would need audio files to be
sent with it.

The context is as follows:
An audio file stored in a buffer is played in small segments in a
forward-backward sequence. Each segment is played after the previous, with
no gaps in time or reading point. First segment goes as 0 - 8638.86, 2nd as
8638.86 - 17277.7, 3rd as 17277.7 - 25916.6 , etc. All segments are
triggered at the same pace, in this case 181.818 ms. You can see all the
segments in the [textfile].
Ideally, the original audio file would be reproduced with no difference to
the original - besides the playback pointer going forward-backward.

But when playing back the segments, after the first initial moment with
almost no problems (only the clicks when playback changes direction),
clicks start to appear at each segment - from around sample 229K onwards.

Since I'm using [vline~], I thought that the timing of the reading point
related to the audio blocks wouldn't be a problem. But, if you record the
output and look at the audio file, you'll see that the clicks come from a
out of phase moment, and then the wave continues.

My question is: am I doing something wrong with the circuit? If not, is
there an efficient way of achieving a similar playback of a stored buffer?

I hope everything is clear. The original patch is a monster, but this
version sums up what's happening.

Btw, in the original patch all the values are calculated in real time. But
with the "recorded" version the audio sound just the same.
The original audio file is 5m18s long. Will the be any round-up problems
while calculating the segment coordinates to tabread4~?

Thanks in advance for who has the time to read this,

Joao
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