fixed abnormal behaviour of audio output in p5.signal example

[endurance21]

fixes #471

before :
carrier.start() was placed inside setup function, and as soon as the script get rendered , user hears a all of a sudden sound of carrier node without the user consent 😬 !!

after:
carrier.start() has been placed inside the canvasPressed() which ensures that output signal is heard by user when it Presses the canvas ! 😀

[endurance21]

@therewasaguy @montoyamoraga
please review this PR !!

[montoyamoraga]

@endurance21 at the right side of the repo i have the option to ask for review, i am going to add myself, do you have that option? just wondering, so that it is easier than tagging.
also, it is easy to miss notifications, we do our best to review them, tag me anytime you need, best!

[endurance21]

@montoyamoraga i do see them, but i am not able to either assign myself or ask for review, i am wondering may be i don't have enough permissions😬

[montoyamoraga]

this is way better, but it would also execute carrier.start() everytime the canvas was pressed, which i don't think it's ideal, this is what i would add:

• a boolean variable called hasStarted to detect if the user has given the consent yet, it is declared false.
• on canvasPressed, first check if that boolean is true or false. if it is false, make it true and execute carrier.start(). after that check, execute carrier.amp(1.0)

this way, at first there is no audio, then only when canvas is pressed the first time, the audio is started and the amplitude is set to 1.0. when mouse is released the amplitude is set to 0.0 yay. then with next clicks, the audio is already sarted, and canvasPressed takes care of setting amplitude to 1.0 every time it is pressed :)

[endurance21]

@montoyamoraga
aha , that's more nicer way to do that ! 😁
also , whenever mouse is Realeased we have to make hasStarted = false

[endurance21]

@montoyamoraga
applied the changes ! ☺️

[montoyamoraga]

can i ask for two little changes?

1. can the boolean be declared in its own line? i find it less confusing.
2. the hasStarted boolean is for being able to signal when the sketch goes from never having outputted audio, to when it started making audio, so it is only needs to become true, but never false again. the muting / unmuting afterwards happens because of the amplitude, i pasted the code here, sorry about the formatting :)

function canvasPressed() {
userStartAudio();

if(!hasStarted){
carrier.start();
hasStarted!=hasStarted;
}

carrier.amp(1.0);

}

function mouseReleased() {
carrier.amp(0);
}

[montoyamoraga]

@endurance21 let me know if it makes sense and if it works please, thank you!
i hadn't used these features for reviewing here on GitHub so i am also learning :)

[endurance21]

@montoyamoraga

1. if you are asking hasStarted = false ? , ya sure , we can sure initilize the boolean at the declaration time !!
2. and yes i agree on it ! , it must be started only once ! i have tested it too, it works fine

[montoyamoraga]

@endurance21 thank you!

yes, i mean having two separate lines like this:

let carrier, modulator;
let hasStarted = false;

[endurance21]

@montoyamoraga
ya that is more intuitive and readable , but i was kind'a avoiding use of multiple let 😅
but i think we should go with you idea ! 😀

[montoyamoraga]

awesome!

[montoyamoraga]

@endurance21 it's a matter of style and use,
i always use one line for every variable declaration,
i'm not sure if we have a formal style guide for p5.js examples,
maybe we should, maybe it's too much :)

[endurance21]

Infact same type of variables must be declared at same line, it enhances code readability 😎