Sequencer Class

Sequencer Class

This is the module that plays the parsed MIDI files using the Synthetizer class.

Importing

import {Sequencer} from "./spessasynth_lib/sequencer/sequencer.js";

Initialization

const sequencer = new Sequencer(parsedMidi, synth);

• parsedMidi - the parsed MIDI file to play, an instance of the MIDI class.
• synth - the synthetizer to use. An instance of the Synthetizer class.

Methods

connectRenderer

Connects an instance of the Renderer class to the sequencer for visualization of the played sequence.

sequencer.connectRenderer(renderer);

• renderer - an instance of the Renderer class to connect the sequencer to.

play

Starts playing the sequence. If the sequence was paused, it won't change any controllers, but if it wasn't (ex. the time was changed) then it will go through all the controller changes from the start before playing. This function does NOT modify the current playback time!

sequencer.play(resetTime);

• resetTime - boolean, if set to true then the playback will start from 0. Defaults to false;

pause

Pauses the playback of the sequence.

sequencer.pause();

stop

Stops the playback of the sequence. Currently only used internally by the pause function.

sequencer.stop();

Properties

paused

Read-only boolean, indicating that if the sequencer's playback is paused.

if(sequencer.paused)
{
   console.log("Sequencer paused!");
}
else
{
   console.log("Sequencer playing or stopped!");
}

loop

Boolean that controls if the sequencer loops.

sequencer.loop = false; // the playback will stop after reaching the end

currentTime

Property used for changing and reading the current playback time.

get

Returns the current playback time in seconds.

console.log("The sequences is playing for"+sequencer.currentTime+" seconds.");

set

Sets the current playback time. Calls stop and then play internally.

sequencer.currentTime = 0; // go to the start

duration

Length of the track in seconds. Equivalent of Audio.duration;

console.log(`The track lasts for ${sequencer.duration} seconds!`);