Change value on runtime

Question

I'm trying to change a value on runtime via a range input but I do not get it to work. I get no errors. When I change the frequence in onSlide the sound does still play on 800. It should change.

import $ from 'jquery';
import rangeslider from 'rangeslider.js';
import T from 'timbre';

window.$ = $;

    $(document).ready(() => {

        var f = 800;

        T("sin", {freq:f, mul:0.5}).play(); /*plays a continous sound*/

        $('input[type="range"]').rangeslider({
            polyfill : false,
            onSlide: function() {
                var ff = 440; /*changing frequancy, but the tone is still the same.*/
                f = ff;
            }
        });

    });

Changing the variable `f` does not call `T` again. What is `T`, can you alter an existing instance? — Bergi, Dec 22 '17 at 10:06
Sorry, edited the code. T is an instance of timbre.js. a sound library. — user2952238, Dec 22 '17 at 10:08
then play() will be called on every change event the slider gets. Wich will just get stuck in a loop of plays()'s — user2952238, Dec 22 '17 at 10:10
`f` is passed by value not reference. So changing `f` after it's been used isn't going to change anything (the memory now points to a different location). You need a method in `T` that will change the frequency (I don't know the library) adjusting the variable is going to do nothing. Concentrate on finding a method in timbre to adjust the frequency as this is a dead end. — Liam, Dec 22 '17 at 10:11
Documentation: https://mohayonao.github.io/timbre.js/ I cant find anyting relative to what i want to do. — user2952238, Dec 22 '17 at 10:12
Then you can't do it. (that said I have never used this library so I don't know for sure) — Liam, Dec 22 '17 at 10:12

score 1 · Answer 1 · answered Dec 22 '17 at 10:13

As shown in Getting Started, you need to store the instance in a variable so that you can call the set method later.

$(document).ready(() => {
    const tone = T("sin", {freq:f, mul:0.5}).play(); /*plays a continous sound*/
    $('input[type="range"]').rangeslider({
        polyfill : false,
        onSlide: function() {
            tone.set( {freq: 440 }); /* changing frequency of the tone */
        }
    });
});

Change value on runtime

1 Answers1