Hoping you can help me. I'm new to using AnimationFrames (started using to meet business requirements). I have managed to make an animation that changes as you scroll (via very helpful codepens) but the issue i have is that it's just adding a new image, and leaving the previous image behind, leaving a trail. (can be seen here: https://aimtechnologies.com/scrolltest/index). I know there's CancelAnimationRequest but im not sure where to put it in to solve my issue?
See below for the code:
const canvas = document.getElementById("hero-lightpass");
const context = canvas.getContext("2d");
const frameCount = 148;
const currentFrame = index => (
`images/1 & 2 Intro & Exploded View_${index.toString().padStart(5, '0')}.png`
)
const preloadImages = () => {
for (let i = 1; i < frameCount; i++) {
const img = new Image();
img.src = currentFrame(i);
}
};
const img = new Image()
img.src = currentFrame(1);
canvas.width=1158;
canvas.height=770;
img.onload=function(){
context.drawImage(img, 0, 0);
}
const updateImage = index => {
img.src = currentFrame(index);
context.drawImage(img, 0, 0);
}
window.addEventListener('scroll', () => {
const scrollTop = html.scrollTop;
const maxScrollTop = html.scrollHeight - window.innerHeight;
const scrollFraction = scrollTop / maxScrollTop;
const frameIndex = Math.min(
frameCount - 1,
Math.ceil(scrollFraction * frameCount)
);
requestAnimationFrame(() => updateImage(frameIndex + 1))
});
preloadImages()```
Try this: context.clearRect(0, 0, canvas.width, canvas.height); right before you call drawImage
Solved: Use JPG's instead of PNGs
Or if you need to use pngs change
context.drawImage(img, 0, 0);
}
``` to ```img.onload=function(){
context.clearRect(0, 0, canvas.width, canvas.height);
context.drawImage(img, 0, 0);
}```