Tone.js/Tone/instrument/Synth.ts
2019-07-18 14:07:25 -04:00

134 lines
3.9 KiB
TypeScript

import { AmplitudeEnvelope } from "../component/envelope/AmplitudeEnvelope";
import { Envelope, EnvelopeOptions } from "../component/envelope/Envelope";
import { ToneAudioNode, ToneAudioNodeOptions } from "../core/context/ToneAudioNode";
import { omitFromObject, optionsFromArguments } from "../core/util/Defaults";
import { readOnly } from "../core/util/Interface";
import { RecursivePartial } from "../core/util/Interface";
import { OmniOscillator, OmniOscillatorOptions } from "../source/oscillator/OmniOscillator";
import { Source, SourceOptions } from "../source/Source";
import { Monophonic, MonophonicOptions } from "./Monophonic";
export interface SynthOptions extends MonophonicOptions {
oscillator: Omit<OmniOscillatorOptions, keyof SourceOptions>;
envelope: Omit<EnvelopeOptions, keyof ToneAudioNodeOptions>;
}
/**
* Synth is composed simply of a Tone.OmniOscillator routed through a Tone.AmplitudeEnvelope.
* ```
* +----------------+ +-------------------+
* | OmniOscillator +>----> AmplitudeEnvelope +>-->Output
* +----------------+ +-------------------+
* ```
* @constructor
* @param options the options available for the synth.
* @example
* var synth = new Synth().toMaster();
* synth.triggerAttackRelease("C4", "8n");
*/
export class Synth extends Monophonic<SynthOptions> {
name = "Synth";
/**
* The oscillator.
*/
readonly oscillator = new OmniOscillator({ context: this.context });
/**
* The frequency signal
*/
readonly frequency = this.oscillator.frequency;
/**
* The detune signal
*/
readonly detune = this.oscillator.detune;
/**
* The envelope
*/
readonly envelope: AmplitudeEnvelope = new AmplitudeEnvelope({ context: this.context });
/**
* The instrument only has an output
*/
input: undefined;
protected _internalChannels = [this.oscillator as unknown as ToneAudioNode, this.envelope, this.output];
constructor(options?: RecursivePartial<SynthOptions>);
constructor() {
super(optionsFromArguments(Synth.getDefaults(), arguments));
const options = optionsFromArguments(Synth.getDefaults(), arguments);
this.oscillator.set(options.oscillator);
this.envelope.set(options.envelope);
// connect the oscillators to the output
this.oscillator.chain(this.envelope, this.output);
readOnly(this, ["oscillator", "frequency", "detune", "envelope"]);
}
static getDefaults(): SynthOptions {
return Object.assign(Monophonic.getDefaults(), {
envelope: Object.assign(
omitFromObject(
Envelope.getDefaults(), ToneAudioNode.getDefaults(),
),
{
attack : 0.005,
decay : 0.1,
release : 1,
sustain : 0.3,
},
),
oscillator: Object.assign(
omitFromObject(
OmniOscillator.getDefaults(), Source.getDefaults(),
),
{
type: "triangle",
},
),
});
}
/**
* start the attack portion of the envelope
* @param time the time the attack should start
* @param velocity the velocity of the note (0-1)
*/
protected _triggerEnvelopeAttack(time?: Time, velocity: number = 1): void {
const computedTime = this.toSeconds(time);
// the envelopes
this.envelope.triggerAttack(computedTime, velocity);
this.oscillator.start(computedTime);
// if there is no release portion, stop the oscillator
if (this.envelope.sustain === 0) {
const computedAttack = this.toSeconds(this.envelope.attack);
const computedDecay = this.toSeconds(this.envelope.decay);
this.oscillator.stop(computedTime + computedAttack + computedDecay);
}
}
/**
* start the release portion of the envelope
* @param time the time the release should start
*/
protected _triggerEnvelopeRelease(time: Time): void {
time = this.toSeconds(time);
this.envelope.triggerRelease(time);
this.oscillator.stop(time + this.toSeconds(this.envelope.release));
}
/**
* clean up
*/
dispose(): this {
super.dispose();
this.oscillator.dispose();
this.envelope.dispose();
return this;
}
}