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MIDI-RtController-Filter-0.0102
/ MIDI::RtController::Filter

NAME

MIDI::RtController::Filter - Parent class of RtController filters

VERSION

version 0.0102

SYNOPSIS


            

              
              
package Your::Filter;
extends 'MIDI::RtController::Filter';

DESCRIPTION

MIDI::RtController::Filter is the parent class of MIDI::RtController filters.

Making filters

All filter methods must accept the object, a MIDI device name, a delta-time, and a MIDI event ARRAY reference, like:


            

              
              
sub breathe ($self, $device, $delta, $event) {
  return 0 if $self->running;
  my ($event_type, $chan, $control, $value) = $event->@*;
  ...
  return $self->continue;
}

A filter also must return a boolean value. This tells MIDI::RtController to continue processing other known filters or not. The continue attribute is used for this purpose.

Calling filters


            

              
              
$controller->add_filter('breathe', note_on => $filter->curry::breathe);

Call the add_filter method on an MIDI::RtController instance. Passing all to the add_filter method means that any MIDI event will fire the filter. But note_on, [qw(note_on note_off)], or control_change works, as well.

ATTRIBUTES

rtc


            

              
              
$controller = $filter->rtc;

A MIDI::RtController instance provided in the constructor.

channel


            

              
              
$channel = $filter->channel;
$filter->channel($number);

The current MIDI channel value between 0 and 15.

Default: 0

value


            

              
              
$value = $filter->value;
$filter->value($number);

Return or set the MIDI event value. This is a generic setting that can be used by filters to set or retrieve state. This often a whole number between 0 and 127, but can be undef.

Default: undef

trigger


            

              
              
$trigger = $filter->trigger;
$filter->trigger($number);

Return or set the trigger. This is a generic setting that can be used by filters to set or retrieve state. This often a whole number between 0 and 127 representing an event note or control-change.

Default: undef

running


            

              
              
$running = $filter->running;
$filter->running($boolean);

Are we running a filter?

Default: 0

halt


            

              
              
$halt = $filter->halt;
$filter->halt($boolean);

This Boolean can be used to terminate running filters.

Default: 0

continue


            

              
              
$continue = $filter->continue;
$filter->continue($boolean);

This Boolean can be used to either stop (1) or continue (0) processing other filters by MIDI::RtController when returned from a filter.

Default: 0

verbose


            

              
              
$verbose = $filter->verbose;

Show progress.

SEE ALSO

Moo

MIDI::RtController

MIDI::RtController::Filter::CC

MIDI::RtController::Filter::Drums

MIDI::RtController::Filter::Tonal

Types::Standard

AUTHOR

Gene Boggs <gene.boggs@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2025 by Gene Boggs.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.