<body>
<canvas id="hero-lightpass"></canvas>
</body>
html {
height: 100vh;
}
body {
background: #000;
height: 500vh;
}
canvas {
position: fixed;
left: 50%;
top: 50%;
max-height: 100vh;
max-width: 100vw;
transform: translate(-50%, -50%);
}
h1 {
color: white;
}
// Canvas settings
const canvas = document.getElementById("hero-lightpass");
const context = canvas.getContext("2d");
canvas.width=1158;
canvas.height=770;
// Preloading images to drastically improve performance
const currentFrame = index => (`https://www.apple.com/105/media/us/airpods-pro/2019/1299e2f5_9206_4470_b28e_08307a42f19b/anim/sequence/large/01-hero-lightpass/${index.toString().padStart(4, '0')}.jpg`);
const frameCount = 148; // There 148 images for that animation-sequence to load
const images = [];
const preloadImages = () => {
for (let i = 1; i < frameCount; i++) {
images[i] = new Image(); // This is functionally equivalent to document.createElement('img').
images[i].src = currentFrame(i);
}
};
preloadImages();
// Draw the first image
const img = new Image();
img.src = currentFrame(1);
img.onload = function(){
context.drawImage(img, 0, 0);
}
// Scroll interactions
const html = document.getElementsByTagName('html');
window.addEventListener('scroll', () => {
const scrollTop = html[0].scrollTop;
// console.log('scrollTop: ', scrollTop);
// console.log('html.scrollHeight: ', html[0].scrollHeight);
// console.log('window.innerHeight: ', window.innerHeight);
const maxScrollTop = html[0].scrollHeight - window.innerHeight;
const scrollFraction = scrollTop / maxScrollTop;
const frameIndex = Math.min(
frameCount - 1,
Math.floor(scrollFraction * frameCount)
);
// console.log('FrameIndex', frameIndex);
requestAnimationFrame(() => context.drawImage(images[frameIndex + 1], 0, 0));
});
This Pen doesn't use any external CSS resources.
This Pen doesn't use any external JavaScript resources.