Re: [PD] stop sample playback when phasor~ reset?

Yeah, a threshold~ set to 1 is never triggered (or very rarely). So there's no perfect answer to the question it seems...

Pierre

2011/9/20 Roman Haefeli reduzent@gmail.com

On Tue, 2011-09-20 at 09:43 +0200, Pierre Massat wrote:

...

I m curious to know which object you would recommend instead of threshold~ (the delay way is obviously not feasible as soon as you need to change the speed of phasor~ during palyback).

Yeah, [threshold~] seems feasible, but this approach suffers from a few issues. As I said before, the bang comes only on block boundaries and is at least one block late, so it's not very precise. Also, a [phasor~] probably never reaches exactly 1 (or 0) and it is less likely the higher the frequency is. So you would need values like 0.001 or 0.999 for the [threshold~] which again makes it a bit more imprecise.

You can also use the [vline~] approach and change the speed in the middle of the playback, though it needs a bit of patching to accomplish that. You need a delay, that is triggered at the time of the speed change. The delay value can be used to calculate the current position of the play head. Then you can use that value as a start point for a new message to [vline~].

Roman

...

2011/9/20 Roman Haefeli reduzent@gmail.com On Mon, 2011-09-19 at 14:00 -0700, Jonathan Wilkes wrote: > > > > > >________________________________ > >From: tim vets timvets@gmail.com > >To: Pierre Massat pimassat@gmail.com; James Dunn james@4thharmonic.com; pd-list pd-list@iem.at > >Sent: Monday, September 19, 2011 4:08 PM > >Subject: Re: [PD] stop sample playback when phasor~ reset? > > > > > >When you use phasor~, you normally already know how long it will take for the sound to be finished playing (because you set its frequency to play it back at the proper speed) > >Store the information about the sound loaded (or recorded) and use that to stop the playback after one play duration. > > > > > >[del <time>] > >| > >[t b b] > >| | > >[0( [0( > >[ | > >[phasor] > > What's the benefit of this over a line~ based approach? >

    [line~] is inferior to [phasor~] in that it only starts a ramp
    on block
    boundaries. Using [vline~] seems to me most flexible in terms
    of sample
    playback as it can start a ramp even in-between samples.

    Using [threshold~] or any other method to detect the reset of
    [phasor~]
    is not feasible, because of two reasons:
     * [threshold] (but also [snapshot~]) output the bang only at
    block
    bounaries, so the detection is not very precise
     * Whenever the the audio domain (a signal) causes an event in
    the
    message domain (that's what [threshold~] and [snapshot~] are
    for), the
    event is at least one block late.

    There is still one advantage of [phasor~] over [vline~]: The
    speed of
    the [phasor~] can be changed at signal rate, so one can create
    continuous pitch changes when playing the sample. That's not
    possible
    with [vline~].

    Roman