<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<div class="m-page--transition"></div>
<button class="btn-r btn-1">reverse</button>
<button class="btn-p btn-1">play</button>
<script src="https://cdn.jsdelivr.net/npm/bezier-easing@2.0.3/src/index.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/gsap/1.20.4/TweenMax.min.js"></script>
<script>
/**
* https://github.com/gre/bezier-easing
* BezierEasing - use bezier curve for transition easing function
* by Gaëtan Renaudeau 2014 - 2015 – MIT License
*/
// These values are established by empiricism with tests (tradeoff: performance VS precision)
var NEWTON_ITERATIONS = 4;
var NEWTON_MIN_SLOPE = 0.001;
var SUBDIVISION_PRECISION = 0.0000001;
var SUBDIVISION_MAX_ITERATIONS = 10;
var kSplineTableSize = 11;
var kSampleStepSize = 1.0 / (kSplineTableSize - 1.0);
var float32ArraySupported = typeof Float32Array === 'function';
function A (aA1, aA2) { return 1.0 - 3.0 * aA2 + 3.0 * aA1; }
function B (aA1, aA2) { return 3.0 * aA2 - 6.0 * aA1; }
function C (aA1) { return 3.0 * aA1; }
// Returns x(t) given t, x1, and x2, or y(t) given t, y1, and y2.
function calcBezier (aT, aA1, aA2) { return ((A(aA1, aA2) * aT + B(aA1, aA2)) * aT + C(aA1)) * aT; }
// Returns dx/dt given t, x1, and x2, or dy/dt given t, y1, and y2.
function getSlope (aT, aA1, aA2) { return 3.0 * A(aA1, aA2) * aT * aT + 2.0 * B(aA1, aA2) * aT + C(aA1); }
function binarySubdivide (aX, aA, aB, mX1, mX2) {
var currentX, currentT, i = 0;
do {
currentT = aA + (aB - aA) / 2.0;
currentX = calcBezier(currentT, mX1, mX2) - aX;
if (currentX > 0.0) {
aB = currentT;
} else {
aA = currentT;
}
} while (Math.abs(currentX) > SUBDIVISION_PRECISION && ++i < SUBDIVISION_MAX_ITERATIONS);
return currentT;
}
function newtonRaphsonIterate (aX, aGuessT, mX1, mX2) {
for (var i = 0; i < NEWTON_ITERATIONS; ++i) {
var currentSlope = getSlope(aGuessT, mX1, mX2);
if (currentSlope === 0.0) {
return aGuessT;
}
var currentX = calcBezier(aGuessT, mX1, mX2) - aX;
aGuessT -= currentX / currentSlope;
}
return aGuessT;
}
function BezierEasing (mX1, mY1, mX2, mY2) {
if (!(0 <= mX1 && mX1 <= 1 && 0 <= mX2 && mX2 <= 1)) {
throw new Error('bezier x values must be in [0, 1] range');
}
// Precompute samples table
var sampleValues = float32ArraySupported ? new Float32Array(kSplineTableSize) : new Array(kSplineTableSize);
if (mX1 !== mY1 || mX2 !== mY2) {
for (var i = 0; i < kSplineTableSize; ++i) {
sampleValues[i] = calcBezier(i * kSampleStepSize, mX1, mX2);
}
}
function getTForX (aX) {
var intervalStart = 0.0;
var currentSample = 1;
var lastSample = kSplineTableSize - 1;
for (; currentSample !== lastSample && sampleValues[currentSample] <= aX; ++currentSample) {
intervalStart += kSampleStepSize;
}
--currentSample;
// Interpolate to provide an initial guess for t
var dist = (aX - sampleValues[currentSample]) / (sampleValues[currentSample + 1] - sampleValues[currentSample]);
var guessForT = intervalStart + dist * kSampleStepSize;
var initialSlope = getSlope(guessForT, mX1, mX2);
if (initialSlope >= NEWTON_MIN_SLOPE) {
return newtonRaphsonIterate(aX, guessForT, mX1, mX2);
} else if (initialSlope === 0.0) {
return guessForT;
} else {
return binarySubdivide(aX, intervalStart, intervalStart + kSampleStepSize, mX1, mX2);
}
}
return function (x) {
if (mX1 === mY1 && mX2 === mY2) {
return x; // linear
}
// Because JavaScript number are imprecise, we should guarantee the extremes are right.
if (x === 0) {
return 0;
}
if (x === 1) {
return 1;
}
return calcBezier(getTForX(x), mY1, mY2);
};
};
var tl = new TimelineLite({ paused:true });
var el = document.querySelector('.m-page--transition');
var play = document.querySelector('.btn-p');
var reverse = document.querySelector('.btn-r');
var easing = BezierEasing(0.645, 0.045, 0.355, 1);
tl.to(el, 0.7, { left: 0, ease: easing })
.to(el, 0.7, { left: '-100%', ease: easing, delay: 0.3, onComplete: finish });
function finish() {
console.log('finish');
}
reverse.addEventListener('click', function() {
tl.reverse();
})
play.addEventListener('click', function() {
tl.play();
})
</script>
/**
* index.scss
* - Add any styles you want here!
*/
body,
html {
background: #0e83cd;
margin: 0;
padding: 0;
font-family: "Lato", sans-serif;
display: flex;
align-items: center;
height: 100%;
justify-content: center;
}
.m-page--transition {
background-color: #7cbdff;
height: 100%;
width: 100%;
position: fixed;
left: 100%;
}
.btn-1 {
border: 3px solid #fff;
color: #fff;
}
.btn-1:hover {
color: #0e83cd;
background: #fff;
}
button {
border: none;
font-family: inherit;
font-size: inherit;
color: inherit;
background: none;
cursor: pointer;
padding: 25px 80px;
display: inline-block;
margin: 15px 30px;
text-transform: uppercase;
letter-spacing: 1px;
font-weight: 700;
outline: none;
position: relative;
transition: all 0.3s;
}
