On 4/18/21 17:06, Martin Peach wrote:
On Sun, Apr 18, 2021 at 6:06 AM IOhannes m zmölnig zmoelnig@iem.at wrote:
I don't really like the timestamp implementation in mrpeach (as it uses real time, rather than logical time), but better this than nothing...
Logical time timestamps would only be accurate inside of the Pd instance.
i tend to disagree. there are basically two use-cases for timetags:
- reducing jitter when synthesising events on the receiver e.g. i want to trigger a drum-synth exactly every 100ms
- reducing jitter when analysing events from the sender e.g. i want to measure the period between two mocap frames
neither of these use-cases warrant system time.
here's a real world example: if i use Pd to send events to my drum-synth, and i want these events to be exactly 100ms apart so I'm driving it with a [metro 100], the real time of these ticks will be very jittery (depending on all sorts of things, starting with the audio buffer of Pd), up to dozens of ms.
if i codify this jitter in the timestamps, then any law abiding receive will have to do their best to reproduce this jitter.
what is the value in that? the only way to schedule two events at exact times I see is to use some "ideal" time - in Pd this is the logical time.
but it would not conform to any OSC specification.
i checked and double checked the specs but could not find anything about this. where do you get the idea that the OSC specs mandate wall clock time? OSC-1.0 speaks about "NTP format" (but this is just the structure of the 64 bits data chunk) and "the number of seconds since midnight on January 1, 1900" (but it doesn't say whether this is supposed to be wallclock or idealized)
It could be added as an option
a flag or similar would be great. there probably are use-cases where real time makes sense, why not be able to cater for both.
f,dst IOhannes