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Re: Timing limitations when programming MIDI with Javascript

From: Jussi Kalliokoski <jussi.kalliokoski@gmail.com>
Date: Tue, 5 Jun 2012 22:43:14 +0300
Message-ID: <CAJhzemXzTz8f016omBJTg8=BiV-S44-r5TWWbkzDVdbZkXJfbw@mail.gmail.com>
To: James Ingram <j.ingram@netcologne.de>
Cc: Chris Wilson <cwilso@google.com>, public-audio@w3.org
On Tue, Jun 5, 2012 at 10:26 PM, James Ingram <j.ingram@netcologne.de>wrote:

> Hi Chris, all,
>         This is actually where the timestamps shine. You can have a
>>        clock interval, like 200 milliseconds, where you proceed
>>        reading a list of events and queue the events that are going
>>        to occur in the following 200ms, and send them to be played at
>>        respective times, without a need for individual setTimeouts
>>        for each event which is very CPU-intensive, and not to mention
>>        that events that are supposed to occur at the same time don't
>>        necessarily do so, maybe due to GC or rendering or whatever is
>>        blocking the next timeout.
>>    I think the penny just dropped! Thanks for your patience. Is this
>>    actually working in Midibridge? Perhaps there should be an example
>>    in the docs...
>> No.  MIDIBridge doesn't currently have timestamps, I don't believe.
> So I'll have to go back to using setTimout() for the moment then (as I
> said, that's not the end of the world).
> Is there any way that I could try using timestamps? That's going to have
> to be done sometime. The sooner the better...

Looking at the code, it looks like MIDIBridge has timestamps, but I'm not
sure if they affect anything, gotta try later.

Received on Tuesday, 5 June 2012 19:43:43 UTC

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