스크롤 효과

1. 스크롤 효과를 만들어보자

1.1. 1단계-섹션1

1.1.1. 좌우이동 - css 메서드 활용

<!DOCTYPE html>
<html lang="ko">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <link rel="stylesheet" href="css/jq-01.css" />
    <script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
    <script src="js/jq-01.js" defer></script>
  </head>

  <body>
    <section class="section1">
      <h2>section1</h2>
      <div class="container">
        <div class="box box1 bg2"></div>
        <div class="box box2 bg3"></div>
      </div>
    </section>
    <section class="section2">
      <h2>section2</h2>
      <div class="box box1 bg4"></div>
      <div class="box box2 bg5"></div>
    </section>
    <section class="section3">
      <h2>section3</h2>
      <div class="box box1 bg2"></div>
      <div class="box box2 bg1"></div>
    </section>
    <section class="section4">
      <h2>section4</h2>
      <div class="box box1 bg2"></div>
      <div class="box box2 bg1"></div>
    </section>
    <section class="section5">
      <h2>section5</h2>
      <div class="box box1 bg2"></div>
      <div class="box box2 bg3"></div>
    </section>
  </body>
</html>

* {
  margin: 0;
  padding: 0;
}
:root {
  --bg1: #285dfb;
  --bg2: #537dfb;
  --bg3: #7e9efc;
  --bg4: #a9befd;
  --bg5: #d4dffe;
}
.bg1 {
  background-color: var(--bg1);
  color: var(--bg5);
}
.bg2 {
  background-color: var(--bg2);
  color: var(--bg4);
}
.bg3 {
  background-color: var(--bg3);
  color: var(--bg3);
}
.bg4 {
  background-color: var(--bg4);
  color: var(--bg2);
}
.bg5 {
  background-color: var(--bg5);
  color: var(--bg1);
}
section {
  overflow: hidden;
  text-align: center;
  width: 100%;
  height: 100vh;
}

section h2 {
  padding: 12vw 6vw;
}

.box {
  display: inline-block; /* clamp (최소,기본,최대)최소, 최대가 명확한 경우 사용가능 */
  width: clamp(100px, 30%, 100%);
  height: 300px;
  transition: all 2s;
}
.box1 {
  transform: translateX(-200%);
}
.box2 {
  transform: translateX(200%);
}
.box.in {
  transform: translateX(-200%);
}

$(window).on('scroll', () => {
  let winSCT;
  const sections = $('section');
  winSCT = $(window).scrollTop();
  sections.each(function (idx, o) {
    $(o).addClass(`bg${idx + 1}`);
    const tg = $(this);
    const tgtop = tg.offset().top;
    if (winSCT > tgtop) {
      tg.find('.box').css('transform', 'translateX(0%)');
    } else if (winSCT > tgtop) {
      tg.find('.box').css('transform', 'translateX(0%)');
    } else if (winSCT > tgtop) {
      tg.find('.box').css('transform', 'translateX(0%)');
    }
  });
});

1.2. 2단계-섹션2

1.2.1. 상하이동 시간차-animate() 메서드 활용

완성화면

<section class="section2">
  <h2>section2</h2>
  <div class="gallery">
    <div class="box bg3"></div>
    <div class="box bg4"></div>
    <div class="box bg5"></div>
  </div>
</section>

.section1 .box {
  display: inline-block;
  /* 최소, 최대가 명확한 경우 사용가능 */
  width: clamp(100px, 30%, 100%);
  height: 300px;
  transition: all 2s;
}

.section1 .box1 {
  transform: translateX(-200%);
}

.section1 .box2 {
  transform: translateX(200%);
}

.section1 .box.in {
  transform: translateX(-200%);
}

.section2 {
  position: relative;
}
.section2 .gallery {
  position: relative;
}
.section2 .gallery .box {
  width: 15vw;
  height: 200px;
  position: absolute;
  opacity: 0;
  top: 100vw;
}

.section2 .bg3 {
  left: 10vw;
}

.section2 .bg4 {
  left: 40vw;
}

.section2 .bg5 {
  right: 10vw;
}

const sections = $('section');
let speed = Math.floor(sections.outerHeight() * 0.2);
let topArr = [];
let winSCT;

sections.each((idx, section) => {
  $(section).addClass(`bg${idx + 1}`);
  const sectionTop = $(section).offset().top;
  topArr.push(sectionTop);
});

$(window).on('scroll', () => {
  winSCT = $(window).scrollTop();
  if (winSCT > topArr[0] winSCT < topArr[1] - speed) {
    sections.eq(0).find('.box').css('transform', 'translateX(0%)');
  }
  if (winSCT > topArr[1] winSCT < topArr[2]) {
    sections.eq(1).find('.bg3').stop().delay(0).animate({ top: '5vw', opacity: 1 }, 500, 'swing');
    sections.eq(1).find('.bg4').stop().delay(100).animate({ top: '0vw', opacity: 1 }, 800, 'swing');
    sections.eq(1).find('.bg5').stop().delay(200).animate({ top: '-5vw', opacity: 1 }, 1100, 'swing');
  }
});

:::note 1단계의 코드는 크게 4가지의 버그가 발생할수 있다.

중복된 조건: if (winSCT > tgtop)같은 조건을 세번 반복 하여 비교하고 있다. 같은 조건이 성립되면 .box 요소의 스타일 또한 여러번 설정될 수 있다.
1. 섹션별 offsetTop 값을 배열로 저장하여 이벤트 핸들러에 전달한다.
부적절한 비교 연산자: 모든 else if 문의 조건이 winSCT > tgtop으로 설정되어 있으므로 첫 번째 if 문과 동일한 조건이다. 결국 두 번째와 세 번째 else if 문은 실행되지 않는다.
1. 배열의 인덱스 번호를 활용하여 조건을 명확하게 지정한다.
변수 범위(scope): winSCT, sections, tg, 그리고 tgtop 변수는 모두 함수 내부에서 선언되었다. 각 섹션 반복문마다 새로운 변수 인스턴스가 생성되므로 원하는 결과를 얻을 수 없을 수 있습니다.
1. 전역변수로 수정한다.
중첩된 스크롤 이벤트 핸들러: 이벤트 핸들러 함수를 최상위 레벨로 작성하게 될경우 추후 하위에 다른 이벤트핸들러를 포함하게 되어 예기치 못한 동작을 초래할수 있다.
1. 반복문과 이벤트 핸들러를 분리한다. :::

1.3. 3단계-섹션3

1.3.1. 리빌효과-addClass() 메서드 활용

마스크효과를 구현해보자

미리보기

<section class="section3">
  <div class="item">
    <h2>section3</h2>
    <figure>
      <img src="http://qwerew.cafe24.com/images/1.jpg" alt="" />
      <figcaption>yum yum</figcaption>
    </figure>
  </div>
  <div class="item">
    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Saepe est nostrum amet eligendi quas fugit libero cumque deserunt voluptate placeat dolorum culpa praesentium reiciendis, aliquid ad illum laborum, harum ratione.</p>
  </div>
</section>

.section3 {
  display: flex;
  color: #333;
  gap: 2rem;
}

.section3 .item:nth-child(1) {
  flex-basis: 60%;
}

.section3 .item:nth-child(2) {
  flex-basis: 40%;
  align-self: center;
}

.section3 figure {
  position: relative;
  box-shadow: -1rem 1rem 3rem -2rem rgba(0, 0, 0, 0.5);
}

.section3 figure:before {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  background: var(--bg1);
  transition: clip-path 0.8s cubic-bezier(0.18, 0.89, 0.32, 1.28);
}

.section3 figure img {
  width: 100%;
  display: block;
  clip-path: inset(0 100% 0 0);
  /* duration 0.6 delay 0.3 */
  transition: clip-path 0.6s 0.3s cubic-bezier(0.18, 0.89, 0.32, 1.28);
}

.section3 figure figcaption {
  position: absolute;
  top: 20px;
  right: 20px;
  padding: 10px;
  font-weight: bold;
  text-transform: uppercase;
  color: #fff;
  background: var(--bg1);
  mix-blend-mode: difference;
  transition: clip-path 0.3s 0.9s cubic-bezier(0.18, 0.89, 0.32, 1.28);
}

.section3 figure::before,
.section3 figure figcaption {
  clip-path: inset(0 0 0 100%);
}

.section3.is-animated figure::before,
.section3.is-animated figure img,
.section3.is-animated figure figcaption {
  clip-path: inset(0);
}

...생략
if (winSCT > topArr[2] && winSCT < topArr[3]-speed) {
  sections.eq(2).addClass('is-animated');
}

1.4. 4단계-섹션4

1.4.1. PIP스크롤

화면안의 화면이 스크롤 되는 효과를 만들어보자

완성화면

미리보기

<section class="section4">
  <h2>section4</h2>
  <div class="container">
    <div class="item left pa">
      <div class="mockup pc">
        <div class="mask"><img src="image/project1_pc.png" alt="" class="screen" /></div>
        <img src="image/desktop.png" alt="" class="device" />
      </div>
      <div class="mockup mobile">
        <div class="mask"><img src="image/project1_mobile.png" alt="" class="screen" /></div>
        <img src="image/mobile.png" alt="" class="device" />
      </div>
    </div>
    <div class="item right bg1 pa"></div>
  </div>
</section>

.section4 .container {
  display: flex;
  position: relative;
}
.pa {
  position: absolute;
  top: 0;
}

.item {
  height: 30vw;
}
.left {
  width: 60vw;
  transition: left 1s ease-in-out;
  left: -100%;
}
.right {
  width: 40vw;
  right: 0;
}
.is-animated .left {
  left: 0;
}
.left .mockup img,
.left .mockup .mask {
  position: absolute;
  top: 0;
  left: 0;
}
.left .mockup.pc {
  margin-left: clamp(5%, 100px, 10%);
  position: relative;
  width: 60%;
  height: 100%;
}

.left .mockup.pc .mask {
  z-index: 3;
  width: 32.3vw;
  height: 61.8%;
  overflow: hidden;
  top: 6%;
  left: 5.2%;
}
.left .mockup.pc img.screen {
  z-index: 1;
  width: 100%;
}
.left .mockup.pc img.device {
  z-index: 2;
  width: 100%;
}
/* mobile */
.left .mockup.mobile {
  z-index: 99;
  position: relative;
  top: -76%;
  left: 58%;
  width: 20%;
  height: 60%;
}

.left .mockup.mobile .mask {
  z-index: 999;
  width: 10.5vw;
  height: 100%;
  overflow: hidden;
  top: 10.8%;
  left: 7%;
  border-radius: 16px 16px 0 0;
}
.left .mockup.mobile img.screen {
  z-index: 3;
  width: 100%;
}
.left .mockup.mobile img.device {
  z-index: 4;
  width: 100%;
}

$(() => {
  const sections = $('section');
  let speed = Math.floor(sections.outerHeight() * 0.3);
  let topArr = [];
  let winSCT;

  sections.each((idx, section) => {
    $(section).addClass(`bg${idx + 1}`);
    const sectionTop = $(section).offset().top;
    topArr.push(sectionTop);
  });

  /* 스크롤함수 */
  $(window).on('scroll', () => {
    winSCT = $(window).scrollTop();
    if (winSCT > topArr[0] && winSCT < topArr[1] - speed) {
      sections.eq(0).find('.box').css('transform', 'translateX(0%)');
    }

    if (winSCT > topArr[1] && winSCT < topArr[2] - speed) {
      sections.eq(1).find('.bg3').stop().delay(100).animate({ top: 0, opacity: 1 }, 500, 'swing');
      sections.eq(1).find('.bg4').stop().delay(200).animate({ top: -100, opacity: 1 }, 800, 'swing');
      sections.eq(1).find('.bg5').stop().delay(300).animate({ top: -200, opacity: 1 }, 1100, 'swing');
    }

    if (winSCT > topArr[2] && winSCT < topArr[3] - speed) {
      console.log(winSCT > topArr[2] && winSCT < topArr[3]);
      sections.eq(2).addClass('is-animated');
    }
    if (winSCT > topArr[3] && winSCT < topArr[4]) {
      sections.eq(3).addClass('is-animated');
    }
  });
  pipScroll();
  function pipScroll() {
    const section = sections.eq(3);
    const devices = ['.mockup.pc', '.mockup.mobile'];

    $.each(devices, function (i, deviceEl) {
      const device = section.find(deviceEl);
      const screen = device.find('.mask>img');
      const mask = device.find('.mask');
      const heightDifference = screen.innerHeight() - mask.innerHeight();
      console.log(device.innerHeight());
      console.log(screen.innerHeight());

      device.on({
        mouseenter: function () {
          if (section.hasClass('is-animated')) {
            screen.stop().animate({ top: -heightDifference }, 1000);
          }
        },
        mouseleave: function () {
          if (section.hasClass('is-animated')) {
            screen.stop().animate({ top: 0 }, 1000);
          }
        },
      });
    });
  }
}); //jQuery

// 윈도우 크기가 변경될 때 heightDifference를 다시 계산.
function pipScroll() {
...생략
$(window).on('resize', function () {
  $.each(devices, function (i, deviceEl) {
    let device = section.find(deviceEl);
    let screen = device.find('.mask>img');
    let mask = device.find('.mask');
    let heightDifference = screen.innerHeight() - mask.innerHeight();

    // heightDifference를 다시 설정.
    device.data('heightDifference', heightDifference);
    console.log(heightDifference);
      });
    });
  }
})//jQuery

1.4.2. PIP스크롤 발전형

여러 섹션에서 사용할수 사용할수 있도록 함수를 수정한다.

미리보기

<section class="section5">
  <div class="container">
    <div class="item left">
      <div class="mockup pc">
        <div class="mask">
          <img src="image/project1_pc.png" alt="" class="screen" />
        </div>
        <img src="image/desktop.png" alt="" class="device" />
      </div>
      <!-- //.mockup.pc -->
      <div class="mockup mobile">
        <div class="mask"><img src="image/project1_mobile.png" alt="" class="screen" /></div>
        <img src="image/mobile.png" alt="" class="device" />
      </div>
      <!-- //.mockup.mobile -->
    </div>
    <!-- //.left -->
    <div class="item right bg1"></div>
  </div>
  <!-- //.right -->
</section>

섹션추가

.section5,
.section4 {
  position: relative;
}
.section5 .container,
.section4 .container {
  position: relative; /* absolute를 제어하는 relative 는 꼭 크기를 넣을것  */
  width: 100%;
  height: 100%;
}
.section5 .item,
.section4 .item {
  position: absolute;
  top: 0;
  height: 30vw;
}
.section5 .item.left,
.section4 .item.left {
  width: 60%; /*  */
  transition: left 1s ease-in-out;
  left: -100%;
}
.section5.is-animated .item.left,
.section4.is-animated .item.left {
  left: 0%;
  transition: left 2s ease-in-out;
}

.section5 .item.right,
.section4 .item.right {
  width: 40%;
  right: 0;
}
.section5 .mockup.pc .mask,
.section4 .mockup.pc .mask {
  z-index: 8;
  width: 32.3vw;
  height: 61.8%;
  overflow: hidden;
  left: 5.2%;
  top: 6%;
}

.section4 선택자에 .section5를 추가

const win = $(window);
const sections = $('section');
let speed = Math.floor(win.height() * 0.5);
let topArr = [];
let winSCT;
console.log(speed);
//sections.offsetTop
sections.each(function (i, o) {
  const sectionTop = $(o).offset().top;
  topArr.push(sectionTop);
});
win.on('scroll', () => {
  winSCT = win.scrollTop();
  if (winSCT > topArr[0] && winSCT < topArr[1]) {
    sections.eq(0).addClass('is-animated').siblings().removeClass('is-animated');
  }
  if (winSCT > topArr[1] - speed && winSCT < topArr[2]) {
    sections.eq(1).addClass('is-animated').siblings().removeClass('is-animated');
  }
  if (winSCT > topArr[2] - speed && winSCT < topArr[3]) {
    sections.eq(2).addClass('is-animated').siblings().removeClass('is-animated');
  }
  if (winSCT > topArr[3] - speed && winSCT < topArr[4]) {
    sections.eq(3).addClass('is-animated').siblings().removeClass('is-animated');
    pipScroll();
    console.log(topArr[4], winSCT);
  }
  if (winSCT > topArr[4] - speed) {
    sections.eq(4).addClass('is-animated').siblings().removeClass('is-animated');
    pipScroll();
  }
});

function pipScroll() {
  const devices = ['.mockup.pc', '.mockup.mobile'];
  $.each(devices, function (i, deviceEl) {
    const device = $(deviceEl);
    const screen = device.find('.screen');
    const mask = device.find('.mask');
    const hightDifference = screen.innerHeight() - mask.innerHeight();
    console.log('hightDifference', hightDifference);
    device.on({
      mouseenter: function () {
        screen.stop().animate({ top: -hightDifference }, 1000);
      },
      mouseleave: function () {
        screen.stop().animate({ top: 0 }, 1000);
      },
    });
  });
}
win.on('resize', function () {
  pipScroll();
});

위의 코드는 화면에는 보이지 않지만 버그가 있다. ['.mockup.pc', '.mockup.mobile'] 에는 단일 요소가 할당 되었으므로두개의 mockup.pc 가 추가 될 경우 각각 동작하지 않는다. 이것을 제이쿼리 객체로 변경하면 여러개 요소를 알아서 반복 처리 하기 때문에 각각 다른 이벤트를 처리할수 있다. 아래처럼 수정하자

  function pipScroll() {
    //const devices = ['.mockup.pc', '.mockup.mobile'];
    const devices = $('.mockup.pc, .mockup.mobile');
    //$.each(devices, function (i, deviceEl) {
    devices.each(function (i, deviceEl) {
      let device = $(this);
      let screen = device.find('.mask>img');

1.5. 가로 스크롤 효과

미리보기

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title></title>
  </head>

  <body>
    <main class="container">
      <section id="section1" class="item">
        <h2 class="num">01</h2>
      </section>
      <section id="section2" class="item">
        <h2 class="num">02</h2>
      </section>
      <section id="section3" class="item">
        <h2 class="num">03</h2>
      </section>
      <section id="section4" class="item">
        <h2 class="num">04</h2>
      </section>
      <section id="section5" class="item">
        <h2 class="num">05</h2>
      </section>
      <section id="section6" class="item">
        <h2 class="num">06</h2>
      </section>
      <section id="section7" class="item">
        <h2 class="num">07</h2>
      </section>
      <section id="section8" class="item">
        <h2 class="num">08</h2>
      </section>
      <section id="section9" class="item">
        <h2 class="num">09</h2>
      </section>
    </main>
  </body>
</html>

.container {
  position: fixed;
  left: 0;
  top: 0;
  display: flex;
}
.item {
  width: 100vw;
  height: 100vh;
  position: relative;
}
#section1 {
  background-color: #111;
}
#section2 {
  background-color: #222;
}
#section3 {
  background-color: #333;
}
#section4 {
  background-color: #444;
}
#section5 {
  background-color: #555;
}
#section6 {
  background-color: #666;
}
#section7 {
  background-color: #777;
}
#section8 {
  background-color: #888;
}
#section9 {
  background-color: #999;
}

.num {
  position: absolute;
  bottom: 20px;
  right: 20px;
  color: #fff;
  font-size: 20vw;
  z-index: 10000;
}

자바스크립트는 gsap 을 사용

<script src="https://unpkg.com/gsap@3/dist/gsap.min.js"></script>

const cont = document.querySelector('.container');
const item = document.querySelector('.item');

function scroll() {
  let scrollTop = window.scrollY;
  let offsetLeft = cont.offsetWidth;
  document.body.style.height = offsetLeft + 'px';

  let viewWidth = offsetLeft - window.innerWidth;
  let viewHeight = offsetLeft - window.innerHeight;
  let goLeft = scrollTop * (viewWidth / viewHeight);

  gsap.to(cont, { left: -goLeft });

  requestAnimationFrame(scroll);
}
scroll();

window.addEventListener('resize', scroll);

const cont = $('.container');
function scroll() {
  let scrollTop = $(window).scrollTop();
  let offsetLeft = cont.outerWidth();
  $('body').css('height', offsetLeft + 'px');

  let viewWidth = offsetLeft - $(window).innerWidth();
  let viewHeight = offsetLeft - $(window).innerHeight();
  let goLeft = scrollTop * (viewWidth / viewHeight);

  cont.css('left', -goLeft);
  console.log(scrollTop, offsetLeft, viewWidth, goLeft, viewHeight);
}
scroll();
$(window).on({
  resize: function () {
    scroll();
  },
  scroll: function () {
    scroll();
  },
});