Re: [AD] midi length + midi frequency

[Kate <statickate@xxxxxxxxxx>]

To answer your MIDI timer question...

Let's take a standard song of 120 beats per minute...

That means that there are 120 beats in 60 seconds, or 120 quarter notes 
every 60 seconds.

So that's 2 quarter notes per second.

Therefore, there are 4 eighth notes per second, 8 sixteenth notes per 
second, 16 thirty second notes per second, and 32 sixty fourth notes per 
second. 

So yes, if the midi timer updates 40 times a second, it can play all 
64th notes of a song with a BPM of 120. 

There's a point however, that the human ear stops distinguishing the 
time intervals between notes.  =P

If Allegro buffers midi info so that in the end all notes are played 
even though some are crunched together if they are less than 1//40th of 
a second apart, there shouldn't be a problem.

I also believe that the playback of notes wouldn't be the biggest thing 
effected by a timer that's too slow.  Many MIDIs use envelopes to 
increase the volume or pitch of notes, and many of those act as a curve 
being updated every 1/100th of a second.  But like I said, I don't think 
the human ear can distinguish, so it's OK. 

Elias Pschernig wrote:

> In response to a request on [Al], attached is a patch which adds a
> function get_midi_length(). While making it, I noticed that the midi
> player only is called 40 times / second. I understand nothing of music
> at all, but I know there are sometimes 64th notes in music (now if that
> means they are 1/64th second long, I don't know) - anyway, it was easy
> to do, so I added another function to change the maximum timer frequency
> the midi player uses. I tried changing it to 64 with some midis I found,
> but can't here any difference to 40.. so maybe this is quite unrelated
> after all.
>
>