This enables the specific use case of checking whether a note's release
phase has ended, but is also potentially useful to implement a sort of
"voice stealing" algorithm in Python code, which can take account of
the note's envelope state as well as other factors specific to the
program.
The underlying routine can return numbers for higher and lower
octaves. Other bits of the code might have frequency limitations
but that doesn't mean we shouldn't let someone get a ~4Hz "note"
by sending in (-12), because that's actually totally plausible as
an LFO frequency.
When there's no sustain, the release step needs to be calculated from
the attack level, not the sustain level. Otherwise, contrary to intent,
this leads to the actual release taking a loooonnngg time.
this has the side effect of making some notes more accurate, the new
frequency= value in the test is closer to the true midi frequency of
830.609...Hz.
and re-vamp overall envelope calculation again.
Now, if you set a low overall attack level like 0.2 this avoids the
"diminishing volume" effect when many notes sound at once. You need
simply choose a maximum attack level that is appropriate for the max
number of voices that will actually be played.
This class allows much more expressive sound synthesis:
* tremolo & vibrato
* arbitrary frequency
* different evelope & waveform per note
* all properties dynamically settable from Python code
This works for me (tested playing midi to raw files on host computer, as
well as a variant of the nunchuk instrument on pygamer)
it has to re-factor how/when MIDI reading occurs, because reasons.
endorse new test results
.. and allow `-1` to specify a note with no sustain (plucked)
In contrast to MidiTrack, this can be controlled from Python code,
turning notes on/off as desired.
Not tested on real HW yet, just the acceptance test based on checking
which notes it thinks are held internally.
a waveform object (array of 'h') can be passed in, replacing the
standard square wave. This waveform must be a 'single cycle waveform'
and some obvious things to pass in are sine, triangle or sawtooth waves,
but you can construct whatever you like.
Originally, black_bindings found each contiguous "//|" block and sent
it to black independently. This was slower than it needed to be.
Instead, swap the comment prefix: when running black, take off
"//|" prefixes and put "##|" prefixes on all un-prefixed lines.
Then, after black is run, do the opposite operation
This more than doubles the overall speed of "pre-commit run --all",
from 3m20s to 55s CPU time on my local machine (32.5s to under 10s
"elapsed" time)
It also causes a small amount of churn in the bindings, because
black now sees enough context to know whether one 'def' follows another
or ends the 'def's in a 'class'. In the latter case, it adds an extra
newline, which becomes a "//|" line.
I'm less sure why a trailing comma was omitted before down in
rp2pio/StateMachine.c but let's roll with it.
