pulp::midi::MidiKeyboardState Class Reference

Tracks the state of all 128 MIDI keys across 16 channels. More...

#include <keyboard_state.hpp>

Public Member Functions
void	process (const MidiEvent &event)
	Process a MIDI event.
bool	is_note_on (uint8_t channel, uint8_t note) const
	Check if a specific note is currently held on a channel.
uint8_t	velocity (uint8_t channel, uint8_t note) const
	Get the velocity of a held note (0 if not held).
int	notes_held (uint8_t channel) const
	Count how many notes are currently held on a channel.
int	total_notes_held () const
	Count total notes held across all channels.
bool	any_notes_held () const
	Check if any note is held on any channel.
int	lowest_note (uint8_t channel) const
	Get the lowest held note on a channel (-1 if none).
int	highest_note (uint8_t channel) const
	Get the highest held note on a channel (-1 if none).
void	all_notes_off ()
	Release all notes on all channels.
void	all_notes_off (uint8_t channel)
	Release all notes on a specific channel.
void	reset ()
	Reset all state without firing callbacks.

Public Attributes
std::function< void(uint8_t channel, uint8_t note, uint8_t velocity)>	on_note_on
	Called when a note turns on.
std::function< void(uint8_t channel, uint8_t note)>	on_note_off
	Called when a note turns off.

Detailed Description

Tracks the state of all 128 MIDI keys across 16 channels.

Processes note on/off events and maintains per-key velocity. Optional listeners are called on state changes for UI updates (e.g. on-screen keyboard highlighting).

MidiKeyboardState keys;
keys.on_note_on = [&](uint8_t ch, uint8_t note, uint8_t vel) {
    highlight_key(note, true);
};
keys.on_note_off = [&](uint8_t ch, uint8_t note) {
    highlight_key(note, false);
};
 
// In process():
for (auto& event : midi_buffer) keys.process(event);
 
// Query:
if (keys.is_note_on(0, 60)) { /* middle C held */ }

Member Function Documentation

all_notes_off() [1/2]

void pulp::midi::MidiKeyboardState::all_notes_off ( )

inline

Release all notes on all channels.

all_notes_off() [2/2]

void pulp::midi::MidiKeyboardState::all_notes_off ( uint8_t channel )

inline

Release all notes on a specific channel.

any_notes_held()

bool pulp::midi::MidiKeyboardState::any_notes_held ( ) const

inline

Check if any note is held on any channel.

highest_note()

int pulp::midi::MidiKeyboardState::highest_note ( uint8_t channel ) const

inline

Get the highest held note on a channel (-1 if none).

is_note_on()

bool pulp::midi::MidiKeyboardState::is_note_on ( uint8_t channel, uint8_t note ) const

inline

Check if a specific note is currently held on a channel.

lowest_note()

int pulp::midi::MidiKeyboardState::lowest_note ( uint8_t channel ) const

inline

Get the lowest held note on a channel (-1 if none).

notes_held()

int pulp::midi::MidiKeyboardState::notes_held ( uint8_t channel ) const

inline

Count how many notes are currently held on a channel.

process()

void pulp::midi::MidiKeyboardState::process ( const MidiEvent & event )

inline

Process a MIDI event.

Note on/off are tracked, and the channel mode messages All Sound Off (CC 120) and All Notes Off (CC 123) release every held note on their channel, firing on_note_off for each, so a panic from a controller cannot leave keys stuck on in a display.

reset()

void pulp::midi::MidiKeyboardState::reset ( )

inline

Reset all state without firing callbacks.

total_notes_held()

int pulp::midi::MidiKeyboardState::total_notes_held ( ) const

inline

Count total notes held across all channels.

velocity()

uint8_t pulp::midi::MidiKeyboardState::velocity ( uint8_t channel, uint8_t note ) const

inline

Get the velocity of a held note (0 if not held).

Member Data Documentation

on_note_off

std::function<void(uint8_t channel, uint8_t note)> pulp::midi::MidiKeyboardState::on_note_off

Called when a note turns off.

on_note_on

std::function<void(uint8_t channel, uint8_t note, uint8_t velocity)> pulp::midi::MidiKeyboardState::on_note_on

Called when a note turns on.

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The documentation for this class was generated from the following file:

• /home/runner/work/pulp/pulp/core/midi/include/pulp/midi/keyboard_state.hpp