remember, that a [loadbang] in a child-patch fires after a [loadbang] in
the parent patch (this is by design).

you could try to call [samplerate~] whenever the DSP is turned on.
something like:

[r pd]
|
[route dsp]
|
| [loadbang]
|/
[bang(
|
[samplerate~]
|
[change]
|

Even better:

[r pd-dsp-started]
|
| [loadbang]
|/
[bang(
|
[samplerate~]
|
[change]
|

"pd dsp" is only sent when switching DSP on *manually*, but Pd will always send a bang to "pd-dsp-started" whenever the DSP state changes (e.g. by messaging the [block~] object). If you only use the samplerate value in DSP calculations, you can even omit the [loadbang].

"pd-dsp-started" / "pd-dsp-stopped" is a rather recent addition (maybe Pd 0.49? I'm not sure). It is also very useful to prevent the "angry [vline~]" *)

Christof

*) When you send messages to the [vline~] object without DSP running, they will gradually pile up and eventually eat all your CPU. "pd-dsp-started"/"pd-dsp-stopped" + [spigot] help to prevent this.

On 2/18/20 8:43 AM, Matt Davey wrote:

Just wondering how cpu intensive the samplerate~ object is?

Is it just receiving from a value inside of pd, or does it need to retrieve
directly from hardware every time?

[samplerate~] reports the internal samplerate of the Pd process, and
trusts that the hardware and Pd agree on that (this is mostly the case,
but sometimes not; e.g. when a hardware/audio-API doesn't support the
requested samplerate and fails to report that back).

We've been running into issues with [loadbang] to samplerate~ and having
the rate change after our loadbangs, so were considering using [bang~].

[samplerate~] also tries to take resampling into account (as defined
with [block~])
i could imagine some glitches at loadbang time if you have a weird (that
involves changing the block-setup with [block~] resp [switch~])

remember, that a [loadbang] in a child-patch fires after a [loadbang] in
the parent patch (this is by design).
if you have a child-patch that uses [loadbang] to query [samplerate~],
and in a parent-patch you use another [loadbang] to change the
re-sampling, then the re-sampling will change *after* you have queried
the samplerate.

Would that be reasonable, even if we might have to do it a few
hundred times?

this seems like overkill.
you could try to call [samplerate~] whenever the DSP is turned on.
something like:

[r pd]
|
[route dsp]
|
| [loadbang]
|/
[bang(
|
[samplerate~]
|
[change]
|


gfmdsar
IOhannes

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