purescript-polyphonic-soundfonts
Deprecated in favour of purescript-soundfonts (which is a re-write in more-or-less pure PureScript and is a drop-in replacement).
This is a PureScript wrapper for danigb's soundfont project: soundfont-player. It differs from purescript-soundfonts in that it allows soundfonts for multiple instruments to reside in memory at the same time - i.e. it allows for polyphonic music. It also uses the latest version of danigb's soundfont-player. Eventually purescript-soundfonts will be deprecated in favour of this library.
It again loads soundfonts taken from Benjamin Gleitzman's package of pre-rendered sound fonts. You may either load a single piano soundfont from a local server or else a set of soundfonts from Benjamin Gleitzman's github server. It then provides functions which allow you to play either an individual note or a sequence of notes.
The description of a MidiNote now contains an indication of the channel (i.e. the polyphonic voice) :
type MidiNote =
{ channel :: Int -- the MIDI channel
. id :: Int -- the MIDI pitch number
, timeOffset :: Number -- the time delay in seconds before the note is played
, duration :: Number -- the duration of the note
, gain :: Number -- the volume (between 0 and 1)
}
We specify a duration for the note which will allow you to play staccato sequences. however, each note 'rings' for 10% more than its alloted time which allows the option of a legato feel whilst still letting each note to be started accurately at tempo. Purescript-aff now incorporates a delay function and this can be used to pace the notes correctly.
Build
Node and npm installed is required. Then run:
npm install
npm run build
Example
To build an example that runs in the browser:
npm run build-example
and then navigate to /example/dist/index.html