Having a button to control a timeline GSAP dynamic - positioning increment counter - javascript

I am trying to control a GSAP animation using a forward & backward button. The expected behaviour I am aiming for is:
When the user hovers over the forward button the animation moves forward (increments in px).
When the user mouseleaves the button then the animation pauses.
When the user hovers over the backwards button the animation moves the other way.
The issue I have encountered is that I have tried to add a dynamic positioning variable in place which increments when the user hovers over the 'forward' button. This is not working as expected - instead it just moves once instead of waiting until the user's mouse leaves to stop.
I tried to add a setInterval to the button event listener to increment the positioning so that when the user hovered over the button it would move px at a time, which did work, but it would not stop causing the browser to crash. I also added a mouseleave to clear the setInterval but I don't think it was good practise.
var masterTimeline = new TimelineMax();
var mousedown = false;
var forwardBTN = document.getElementById("forward");
var backwardBTN = document.getElementById("backward");
var pauseBTN = document.getElementById("pause");
var blueboxElement = document.getElementById("blueBox");
var direction = '+';
var counter = 0;
var distance = 0;
var value1 = direction + '=' + distance;
var tween;
forwardBTN.addEventListener("mouseenter", function(){
// setInterval(function() {
directionMove('moveForward');
// }, 500);
});
backwardBTN.addEventListener("mouseenter", function(){
directionMove('moveBackward')
});
pauseBTN.addEventListener("click", function(){
directionMove('pause');
});
function directionMove(playk) {
if (playk == 'moveBackward') {
var direction = '-';
value1 = direction + '=' + distance; // how to update value
masterTimeline.to(blueboxElement, 0.1, {css: {x: value1}, ease: Linear.easeNone}); // no need move by default
}
else if (playk == 'moveForward') {
var direction = '+';
value1 = direction + '=' + distance; //how to update value
masterTimeline.to(blueboxElement, 0.1, {css: {x: value1}, ease: Linear.easeNone}); // no need move by default
}
else if (playk == 'pause') {
masterTimeline.kill();
console.log("killed");
//
}
}```
The expected behaviour is to move forward incrementally without stopping until the user moves off the forward button but at present it is just moving a single amount one time.
Here is a CodePen link if this helps:
https://codepen.io/nolimit966/pen/pXBeZv?editors=1111

I think you're overcomplicating this a bit (at least in the demo). The entire point of GSAP is moving things along a timeline. What you're trying to do is essentially forcibly use a timeline to work in a non-timeline way, which is why I think you're having trouble.
If you step back and just think about your three requirements, I think it becomes a lot more simple. It's always good to think about it in words like you did because it can help you simplify it and understand it better.
The key steps are to:
Create a timeline for the movement of the box.
Play the timeline forward when the forward button is hovered.
2b. Pause it when it's no longer hovered.
Play the timeline backward when the reverse button is hovered.
3b. Pause it when it's no longer hovered.
In code that looks like this:
var tl = new TimelineMax({paused: true});
var forwardBTN = document.getElementById("forward");
var backwardBTN = document.getElementById("backward");
var pauseBTN = document.getElementById("pause");
var blueboxElement = document.getElementById("blueBox");
tl.to(blueboxElement, 10, {x: window.innerWidth - blueboxElement.clientWidth, ease: Linear.easeNone});
function pause() {
tl.pause();
}
forwardBTN.addEventListener("mouseenter", function() {
tl.play();
});
forwardBTN.addEventListener("mouseleave", pause);
backwardBTN.addEventListener("mouseenter", function() {
tl.reverse();
});
backwardBTN.addEventListener("mouseleave", pause);
Demo
By the way, you're much more likely to get a faster response over on the official GreenSock forums :)

Do you mean something like this?
var tl = new TimelineMax({paused: true});
tl.to('.element', 3, {
x: 800,
});
$(document).on({
mouseenter: function () {
if($(this).hasClass('forward')){
tl.play();
}
else if($(this).hasClass('backwards')){
tl.reverse();
}
},
mouseleave: function () {
tl.pause();
}
}, ".btn");
.wrapper{
width: 100%;
padding: 40px;
}
.element{
width: 100px;
height: 100px;
background: red;
}
.btn{
display: inline-block;
padding: 15px;
background: #bbb;
margin-top: 20px;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/gsap/2.1.3/TweenMax.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div class="wrapper">
<div class="element_wrapper">
<div class="element"></div>
</div>
<div class="forward btn">Forward</div>
<div class="backwards btn">Backwards</div>
</div>

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height: 200vh;
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