Scrolltrigger after initial images of sequence is played

[Mohit Tilwani]

Hey GSAP Team,

I am trying to achieve an animation where on page load, initial sequence of images are played and only after that scroll should be enabled and scroll trigger should take over and play sequence of image on scroll. I am able to achieve the first part of playing image sequence on page load, but stuck on the second part. Can you please nudge me in the right direction 🙏 Thanks. Below is my Vuejs code
 

<script>
import { gsap } from 'gsap'

export default {
  data() {
    return {
      canvas: null,
      context: null,
      images: [],
      images2: [],
      frames: { currentFrame: 0 },
      frames2: { currentFrame: 64 }
    }
  },
  mounted() {
    this.initializeCanvas()
    this.loadImages()
    this.initializeAnimation()
  },
  methods: {
    initializeCanvas() {
      this.canvas = this.$refs.canvas
      this.context = this.canvas.getContext('2d')
    },
    getFrameURL(index) {
      return `http://localhost:5173/demo-${(index)
        .toString()
        .padStart(4, '0')}.png`
    },
    loadImages() {
      for (let i = 0; i < 64; i++) {
        const img = new Image()
        img.src = this.getFrameURL(i)
        this.images.push(img)

        if ( i === 0) this.render()
      }
      for (let i = 64; i < 300; i++) {
        const img = new Image()
        img.src = this.getFrameURL(i)
        this.images2.push(img)
      }
    },
    initializeAnimation() {
      const tl = gsap.timeline()
      tl.to(this.frames, {
        currentFrame: 64 - 1,
        snap: 'currentFrame',
        ease: 'power1.inOut',
        duration: 2,
        onUpdate: this.render
      })
      tl.to(this.canvas,
        {
          y: 400,
          duration: 2,
          onComplete: () => {
            this.canvas.classList.add('canvas-moved')
          }
        })
      tl.to(this.frames2, {
        currentFrame: 299,
        snap: 'currentFrame',
        ease: 'power1.inOut',
        scrollTrigger: {
          trigger: '.canvas-moved',
          start: 'top top', 
          end: '+=300%',
          scrub: 1,
          markers: true
        },
        onUpdate: this.render2
      })
    },
    render() {
      this.context.clearRect(0, 0, this.canvas.width, this.canvas.height)
      const img = this.images[this.frames.currentFrame]
      const scale = Math.min(this.canvas.width / img.width, this.canvas.height / img.height)
      this.context.drawImage(img, 0, 0, img.width * scale, img.height * scale)
    },
    render2() {
      this.context.clearRect(0, 0, this.canvas.width, this.canvas.height)
      const img = this.images2[this.frames2.currentFrame - 64]
      console.log(this.frames2.currentFrame)
      console.log(img)
      const scale = Math.min(this.canvas.width / img.width, this.canvas.height / img.height)
      this.context.drawImage(img, 0, 0, img.width * scale, img.height * scale)
    }
  }
}
</script>

<template>
  <div class="canvas-container">
    <canvas ref="canvas" width="1560" height="1040" />
  </div>
</template>

<style scoped>
.canvas-container {
  position: relative;
  width: 100%;
  height: 100vh;
  overflow: hidden;
  z-index: 10;
}

canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  will-change: opacity;
}
</style>

[GSAP Helper]

Without a minimal demo, it's very difficult to troubleshoot; the issue could be caused by CSS, markup, a third party library, a 3rd party script, etc. Would you please provide a very simple CodePen or Stackblitz that illustrates the issue? 

 

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

 

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

that loads all the plugins. Just click "fork" at the bottom right and make your minimal demo: 

 

Using a framework/library like React, Vue, Next, etc.? 

CodePen isn't always ideal for these tools, so here are some Stackblitz starter templates that you can fork and import the gsap-trial NPM package for using any of the bonus plugins: 

• React (please read this article!)
• Next
• Svelte
• Sveltekit
• Vue
• Nuxt

 

Please share the StackBlitz link directly to the file in question (where you've put the GSAP code) so we don't need to hunt through all the files. 

 

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

[Rodrigo]

Hi,

 

Besides echoing the need of a minimal demo, you can set the overflow property of the body tag in your CSS to hidden and when the initial images animation sequence is completed, you can use the onComplete callback to change the overflow property to auto and create the ScrollTrigger instances or call ScrollTrigger refresh in order to update the ScrollTrigger instances that could've been created before running that initial image sequence.

 

https://developer.mozilla.org/en-US/docs/Web/CSS/overflow

 

Happy Tweening!

[Mohit Tilwani]

@RodrigoThanks for the reply. I have created a minimal demo. Can you assist me to add Scroll trigger after initial image sequence is played.

See the Pen yLdpdXY by MohitTilwani15 (@MohitTilwani15) on CodePen.

[mvaneijgen]

Hi @Mohit Tilwani welcome to the forum!

 

Your code seems to work perfectly fine, your only issue is that there is nothing to scroll, so changing overflow: hidden to auto does nothing, because the page is already fully scrolled. In the below pen I've just add some extra space to scroll by and it works perfectly. Hope it helps and happy tweening! 

 

See the Pen zYVpVmd by mvaneijgen (@mvaneijgen) on CodePen.