parallel vertical carousel with different directions

[karzol73]

Hello All

I am working on a Vue3 component with two parallel vertical carousels. The one on the left is moving from top to bottom, while the other on the right is moving from bottom to top. My problem is that the left carousel is working well with an infinite loop of the cards, but the right carousel is not infinite.

 

Thank your for your help in advance!

<template>
    <div
        class="100vh overflow-hidden"
        :class="`wrapper-${name}`"
    >
        <div
            :class="`pictures-${name}`"
            class=""
        >
            <img
                v-for="(card, idx) in props.cards"
                :key="idx"
                class="w-[14vw] block py-3"
                :class="`picture-${name}`"
                :src="cardURL(card)"
                alt="card"
            >
        </div>
    </div>
</template>
  
<script setup>
import { onMounted, ref } from 'vue';
import { gsap } from 'gsap';
import { Draggable } from 'gsap/all'
import { InertiaPlugin } from 'gsap/all';

gsap.registerPlugin(Draggable, InertiaPlugin)

const props = defineProps({
    cards: {
        type: Array,
        required: true,
    },
    name: {
        type: String,
        required: true,
    },
    reverse: {
        type: Boolean,
        required: false,
        default: false,
    }
});

const cardURL = (img) => {
    return `/card/${img}.png`
}

const pictures = ref(null);
let counter = ref(0);

function startAnim() {
    const totalHeight = pictures.value.querySelector(`.pictures-${props.name}`).offsetHeight;

    pictures.value.querySelectorAll(`.picture-${props.name}`).forEach((picture, i) => {
        const pictureHeight = picture.offsetHeight;
        const pictureOffset = picture.offsetTop;
        const pictureDistance = pictureHeight + pictureOffset;

        const tl = gsap.timeline({ repeat: -1, defaults: { ease: "none", duration: 20 } });

        if (props.reverse) {

            tl.to(picture, {
                y: `+=${totalHeight}`,
                modifiers: {
                    y: function (y, target) {
                        y = parseFloat(y);
                        if (y >= pictureDistance) {
                            y -= totalHeight;
                        }
                        return y + "px";
                    },
                },
            }, 0);

        } else {

            tl.to(picture, {
                y: `-=${totalHeight}`,
                modifiers: {
                    y: function (y, target) {
                        y = parseFloat(y);
                        if (y < -pictureDistance) {
                            y += totalHeight;
                        }
                        return y + "px";
                    },
                },
            }, 0);

        }
    });
}

function incrementCounter() {
    counter.value++;
    if (counter.value === pictures.value.querySelectorAll(`.picture-${props.name}`).length) {
        startAnim();
    }
}

onMounted(() => {
    pictures.value = document.querySelector(`.wrapper-${props.name}`);
    const allPictures = document.querySelectorAll(`.picture-${props.name}`);

    allPictures.forEach((picture) => {
        if (picture.complete) {
            incrementCounter();
        } else {
            picture.addEventListener('load', incrementCounter);
        }
    });
});
</script>

 

 

 

[GSAP Helper]

It's pretty tough to troubleshoot without a minimal demo - the issue could be caused by CSS, markup, a third party library, your browser, an external script that's totally unrelated to GSAP, etc. Would you please provide a very simple CodePen or Stackblitz that demonstrates the issue? 

 

Please don't include your whole project. Just some colored <div> elements and the GSAP code is best (avoid frameworks if possible). See if you can recreate the issue with as few dependancies as possible. If not, incrementally add code bit by bit until it breaks. Usually people solve their own issues during this process! If not, then at least we have a reduced test case which greatly increases your chances of getting a relevant answer.

 

Here's a starter CodePen that loads all the plugins. Just click "fork" at the bottom right and make your minimal demo: 

See the Pen aYYOdN by GreenSock (@GreenSock) on CodePen

 

If you're using something like React/Next/Vue/Nuxt or some other framework, you may find StackBlitz easier to use. We have a series of collections with different templates for you to get started on these different frameworks: React/Next/Vue/Nuxt.

 

Once we see an isolated demo, we'll do our best to jump in and help with your GSAP-specific questions. 

[Rodrigo]

Hi,

 

You can check the Vertical Endless Loop helper function.

 

Here is a simple demo:

See the Pen abaQdwe by GreenSock (@GreenSock) on CodePen

 

Hopefully this helps.

Happy Tweening!

[karzol73]

Thank you, @Rodrigo! I'll check it.