[PD] triggering vline~ compared with line~

[Roman Haefeli]

hi frank


i don't think that vline~ is off. i rather think it is more accurate (as
it is said in helpfile), even more accurate than sample-accurate. i
attached a patch, that should show the accuracy of vline~.  it seems
that vline~, when getting messages from a [del] or a [metro],  knows  to
which time the bang 'is thought' to be executed.

my question is [to the devs]:
how does vline~ get this information? is the there something like a
timestamp attached to the messages from [del] and [metro] (like: 'bang'
+ 'shoud be executed at sample 23 of the block')? if yes, which objs,
besides [metro] and [del], do attach this info? on the other hand, which
obj (besides [vline~]) do consider this info?

(i could be well, that i am asking the wrong questions, since i don't
know much about the pd-internals)

cheers
roman


"Frank Barknecht" wrote:

> Hallo,
> Enrique Erne hat gesagt: // Enrique Erne wrote:
>
> > triggering [0, 1 2 0( -> [vline~] by [bang( or [bng]
> > and writing its outlet to an array with [tabwrite~]
> > gives me a line starting at the beginning of the array.
> >
> > doing the same with a [metro] instead [bng] or [bang(
> > gives me start position 'jumping' around . it seems that
> > the [vline~] starts too late (after the [tabwrite~] has started) .
>
> I think you have found a bug. However I have no idea, where. I would
> suppose it's somewhere in [vline~]. I noted, that vline~'s starting
> point seems to be off in an area between 0 and 64 samples, which is
> exactly Pd's default block size. If you change the blocksize like in
> [block~ 128] then [vline~] is off up to 128 samples. Somewhere there
> seems to be a mismatch between the time, the metro bangs arrive at
> [tabwrite~] and the time internal to [vline~]. I also tested resetting
> the phase of a [phasor~ 500] and recording this into a table. The
> [phasor~] gets recorded correctly starting at array position 0. So
> it's only [vline~] that's off.
>
> Ciao
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