Crate midi_fundsp 

This crate enables the construction of synthesizers with live MIDI input and sound synthesis using fundsp.

It is organized as follows:

• The crate root contains functions and data structures useful for constucting fundsp sounds.
  • MIDI input messages are converted into SharedMidiState objects that translate the sounds represented by those messages into fundsp Shared atomic variables.
  • SynthFunc functions translate SharedMidiState objects into specific fundsp audio graphs.
• The io module contains functions and data types for obtaining messages from MIDI devices and playing
  fundsp audio graphs through the computer’s speakers.
• The sound_builders module contains functions that wrap fundsp audio graphs into SynthFunc functions with a variety of properties.
• The sounds module contains SynthFunc functions that produce a variety of live sounds.

The following example programs show how these components interact to produce a working synthesizer:

• basic_demo.rs opens the first MIDI device it finds and plays a simple triangle waveform sound in response to MIDI events.
• stereo_demo.rs also opens the first MIDI device it finds. It plays notes below middle C through the left speaker using a Moog Pulse sound, and notes at Middle C or higher through the right speaker using a Moog Triangle sound.
• choice_demo.rs allows the user to choose one from among all connected MIDI devices. The user can then choose any sound from the sounds module for the program’s response to MIDI events.
• just_tempered_demo.rs shows how to use an alternative function for converting MIDI notes to frequencies. This specific alternative function uses Just Intonation instead of equal temperament.
• cc_demo.rs demonstrates the use of a sound with properties altered by a MIDI Control Change message. The Control Change channel is specified by a generic constant for the MusicBox sound type. (It is set at 7 in this example because that is a convenient Control Change channel for my own MIDI keyboard.) This illustrates how to build and employ sounds using MIDI Control Change for any application you might imagine.

Modules

io

sound_builders

sounds

tunings

Macros

program_table

Convenience macro to build a ProgramTable. Given a sequence of tuples of &str objects and SynthFunc objects, it returns a proper ProgramTable.

Structs

SharedMidiState

SharedMidiState objects represent as fundsp Shared atomic variables the following MIDI events:

SoundTestResult

When designing sounds, it can be useful to understand their typical output levels. SoundTestResult objects track the minimum, maximum, and mean output levels.

Constants

CONTROL_OFF

Control value in response to Note Off event.

CONTROL_ON

Control value in response to Note On event.

DURATION

Duration of test for SoundTestResult.

MAX_MIDI_VALUE

MIDI values for pitch and velocity range from 0 to 127.

NUM_MIDI_VALUES

Total quantity of distinct MIDI values.

SAMPLE_RATE

Sample rate of 44.1 kHz for use in SoundTestResult.

Functions

control_change_from

If a given MidiMsg object is encapsulating a ControlChange it returns the control id and value values of that message.

note_velocity_from

If a given MidiMsg object is a NoteOn or NoteOff message, it returns the note and velocity values of that message.

pitch_bend_factor

Converts MIDI pitch-bend message to frequency multiplier over +/- 1 semitone using this algorithm.

semitone_from

Converts MIDI pitch-bend message to +/- 1 semitone using this algorithm.

Type Aliases

SynthFunc

SynthFunc objects translate SharedMidiState values into fundsp audio graphs.