( () => {
let yOffset = 0; // window.pageYOffset 대신 사용 할 변수
let prevScrollHeight = 0; //현재 스크롤 위치(yOffset)보다 이전에 위치한 스크롤 섹션들의 스크롤 높이 값의 합
let currentScene = 0; // 현재 활성화 된 (눈 앞에 보고 있는) 씬(scroll-section)
let enterNewScene = false; //새로운 씬이 시작된 순간 true
const sceneInfo = [
{
// 0
type: 'sticky',
heightNum: 5, // 브라우저 높이의 5배로 scrollHeight 세팅
scrollHeight: 0,
objs: {
container: document.querySelector('#scroll-section-0'),
messageA: document.querySelector('#scroll-section-0 .main-message.a'),
messageB: document.querySelector('#scroll-section-0 .main-message.b'),
messageC: document.querySelector('#scroll-section-0 .main-message.c'),
messageD: document.querySelector('#scroll-section-0 .main-message.d')
},
values: {
messageA_opacity_in: [0, 1, { start: 0.1, end: 0.2 }],
messageB_opacity_in: [0, 1, { start: 0.3, end: 0.4 }],
messageC_opacity_in: [0, 1, { start: 0.5, end: 0.6 }],
messageD_opacity_in: [0, 1, { start: 0.7, end: 0.8 }],
messageA_translateY_in: [20, 0, { start: 0.1, end: 0.2 }],
messageB_translateY_in: [20, 0, { start: 0.3, end: 0.4 }],
messageC_translateY_in: [20, 0, { start: 0.5, end: 0.6 }],
messageD_translateY_in: [20, 0, { start: 0.7, end: 0.8 }],
messageA_opacity_out: [1, 0, { start: 0.25, end: 0.3 }],
messageB_opacity_out: [1, 0, { start: 0.45, end: 0.5 }],
messageC_opacity_out: [1, 0, { start: 0.65, end: 0.7 }],
messageD_opacity_out: [1, 0, { start: 0.85, end: 0.9 }],
messageA_translateY_out: [0, -20, { start: 0.25, end: 0.3 }],
messageB_translateY_out: [0, -20, { start: 0.45, end: 0.5 }],
messageC_translateY_out: [0, -20, { start: 0.65, end: 0.7 }],
messageD_translateY_out: [0, -20, { start: 0.85, end: 0.9 }]
}
},
{
// 1
type: 'normal',
// heightNum: 5, // type normal에서는 필요 없음
scrollHeight: 0,
objs: {
container: document.querySelector('#scroll-section-1')
}
},
{
// 2
type: 'sticky',
heightNum: 5,
scrollHeight: 0,
objs: {
container: document.querySelector('#scroll-section-2'),
messageA: document.querySelector('#scroll-section-2 .a'),
messageB: document.querySelector('#scroll-section-2 .b'),
messageC: document.querySelector('#scroll-section-2 .c'),
pinB: document.querySelector('#scroll-section-2 .b .pin'),
pinC: document.querySelector('#scroll-section-2 .c .pin')
},
values: {
messageA_translateY_in: [20, 0, { start: 0.15, end: 0.2 }],
messageB_translateY_in: [30, 0, { start: 0.6, end: 0.65 }],
messageC_translateY_in: [30, 0, { start: 0.87, end: 0.92 }],
messageA_opacity_in: [0, 1, { start: 0.25, end: 0.3 }],
messageB_opacity_in: [0, 1, { start: 0.6, end: 0.65 }],
messageC_opacity_in: [0, 1, { start: 0.87, end: 0.92 }],
messageA_translateY_out: [0, -20, { start: 0.4, end: 0.45 }],
messageB_translateY_out: [0, -20, { start: 0.68, end: 0.73 }],
messageC_translateY_out: [0, -20, { start: 0.95, end: 1 }],
messageA_opacity_out: [1, 0, { start: 0.4, end: 0.45 }],
messageB_opacity_out: [1, 0, { start: 0.68, end: 0.73 }],
messageC_opacity_out: [1, 0, { start: 0.95, end: 1 }],
pinB_scaleY: [0.5, 1, { start: 0.6, end: 0.65 }],
pinC_scaleY: [0.5, 1, { start: 0.87, end: 0.92 }]
}
},
{
// 3
type: 'sticky',
heightNum: 5,
scrollHeight: 0,
objs: {
container: document.querySelector('#scroll-section-3'),
canvasCaption: document.querySelector('.canvas-caption')
},
values: {
}
}
];
function setLayout(){
//각 스크롤 섹션의 높이 세팅
for (let i = 0; i < sceneInfo.length; i++) {
if (sceneInfo[i].type === 'sticky'){
sceneInfo[i].scrollHeight = sceneInfo[i].heightNum * window.innerHeight;
} else if (sceneInfo[i].type === 'normal'){
sceneInfo[i].scrollHeight = sceneInfo[i].objs.container.offsetHeight;
}
sceneInfo[i].objs.container.style.height = `${sceneInfo[i].scrollHeight}px`;
}
yOffset = window.pageYOffset;
let totalScrollHeight = 0;
for (let i = 0; i < sceneInfo.length; i++) {
totalScrollHeight += sceneInfo[i].scrollHeight;
if (totalScrollHeight >= yOffset) {
currentScene = i;
break;
}
}
document.body.setAttribute('id', `show-scene-${currentScene}`);
}
function calcValues(values, currentYOffset){
let rv;
//현재 씬( 스크롤 섹션 ) 에서 스크롤 된 범위를 비율로 구하기
const scrollHeight = sceneInfo[currentScene].scrollHeight;
const scrollRatio = currentYOffset / scrollHeight;
if (values.length === 3) {
// start ~ end 사이에 애니메이션 실행
const partScrollStart = values[2].start * scrollHeight;
const partScrollEnd = values[2].end * scrollHeight;
const partScrollHeight = partScrollEnd - partScrollStart;
if (currentYOffset >= partScrollStart && currentYOffset <= partScrollEnd){
rv = (currentYOffset - partScrollStart) / partScrollHeight * (values[1] - values[0]) + values[0];
} else if (currentYOffset < partScrollEnd){
rv = values[0];
} else if (currentScene > partScrollEnd) {
rv = values[1];
}
} else {
rv = scrollRatio * (values[1] - values[0]) + values[0];
}
return rv;
}
function playAnimation() {
const objs = sceneInfo[currentScene].objs;
const values = sceneInfo[currentScene].values;
const currentYOffset = yOffset - prevScrollHeight;
const scrollHeight = sceneInfo[currentScene].scrollHeight;
const scrollRatio = currentYOffset / scrollHeight;
switch (currentScene) {
case 0:
// console.log('0 play');
if (scrollRatio <= 0.22) {
// in
objs.messageA.style.opacity = calcValues(values.messageA_opacity_in, currentYOffset);
objs.messageA.style.transform = `translate3d(0, ${calcValues(values.messageA_translateY_in, currentYOffset)}%, 0)`;
} else {
// out
objs.messageA.style.opacity = calcValues(values.messageA_opacity_out, currentYOffset);
objs.messageA.style.transform = `translate3d(0, ${calcValues(values.messageA_translateY_out, currentYOffset)}%, 0)`;
}
if (scrollRatio <= 0.42) {
// in
objs.messageB.style.opacity = calcValues(values.messageB_opacity_in, currentYOffset);
objs.messageB.style.transform = `translate3d(0, ${calcValues(values.messageB_translateY_in, currentYOffset)}%, 0)`;
} else {
// out
objs.messageB.style.opacity = calcValues(values.messageB_opacity_out, currentYOffset);
objs.messageB.style.transform = `translate3d(0, ${calcValues(values.messageB_translateY_out, currentYOffset)}%, 0)`;
}
if (scrollRatio <= 0.62) {
// in
objs.messageC.style.opacity = calcValues(values.messageC_opacity_in, currentYOffset);
objs.messageC.style.transform = `translate3d(0, ${calcValues(values.messageC_translateY_in, currentYOffset)}%, 0)`;
} else {
// out
objs.messageC.style.opacity = calcValues(values.messageC_opacity_out, currentYOffset);
objs.messageC.style.transform = `translate3d(0, ${calcValues(values.messageC_translateY_out, currentYOffset)}%, 0)`;
}
if (scrollRatio <= 0.82) {
// in
objs.messageD.style.opacity = calcValues(values.messageD_opacity_in, currentYOffset);
objs.messageD.style.transform = `translate3d(0, ${calcValues(values.messageD_translateY_in, currentYOffset)}%, 0)`;
} else {
// out
objs.messageD.style.opacity = calcValues(values.messageD_opacity_out, currentYOffset);
objs.messageD.style.transform = `translate3d(0, ${calcValues(values.messageD_translateY_out, currentYOffset)}%, 0)`;
}
break;
case 2:
// console.log('2 play');
if (scrollRatio <= 0.32) {
// in
objs.messageA.style.opacity = calcValues(values.messageA_opacity_in, currentYOffset);
objs.messageA.style.transform = `translate3d(0, ${calcValues(values.messageA_translateY_in, currentYOffset)}%, 0)`;
} else {
// out
objs.messageA.style.opacity = calcValues(values.messageA_opacity_out, currentYOffset);
objs.messageA.style.transform = `translate3d(0, ${calcValues(values.messageA_translateY_out, currentYOffset)}%, 0)`;
}
if (scrollRatio <= 0.67) {
// in
objs.messageB.style.transform = `translate3d(0, ${calcValues(values.messageB_translateY_in, currentYOffset)}%, 0)`;
objs.messageB.style.opacity = calcValues(values.messageB_opacity_in, currentYOffset);
objs.pinB.style.transform = `scaleY(${calcValues(values.pinB_scaleY, currentYOffset)})`;
} else {
// out
objs.messageB.style.transform = `translate3d(0, ${calcValues(values.messageB_translateY_out, currentYOffset)}%, 0)`;
objs.messageB.style.opacity = calcValues(values.messageB_opacity_out, currentYOffset);
objs.pinB.style.transform = `scaleY(${calcValues(values.pinB_scaleY, currentYOffset)})`;
}
if (scrollRatio <= 0.93) {
// in
objs.messageC.style.transform = `translate3d(0, ${calcValues(values.messageC_translateY_in, currentYOffset)}%, 0)`;
objs.messageC.style.opacity = calcValues(values.messageC_opacity_in, currentYOffset);
objs.pinC.style.transform = `scaleY(${calcValues(values.pinC_scaleY, currentYOffset)})`;
} else {
// out
objs.messageC.style.transform = `translate3d(0, ${calcValues(values.messageC_translateY_out, currentYOffset)}%, 0)`;
objs.messageC.style.opacity = calcValues(values.messageC_opacity_out, currentYOffset);
objs.pinC.style.transform = `scaleY(${calcValues(values.pinC_scaleY, currentYOffset)})`;
}
break;
case 3:
// console.log('3 play');
break;
}
}
// 스크롤 되면 실행되는 함수 (몇번째 섹션이 스크롤 중인지 판별하는 역할)
function scrollLoop() {
enterNewScene = false;
prevScrollHeight = 0;
for (let i = 0; i < currentScene; i++) {
prevScrollHeight += sceneInfo[i].scrollHeight;
}
if (yOffset > prevScrollHeight+sceneInfo[currentScene].scrollHeight){
enterNewScene = true;
currentScene++;
document.body.setAttribute('id', `show-scene-${currentScene}`);
}
if (yOffset < prevScrollHeight) {
enterNewScene = true;
if(currentScene === 0) return //브라우저 바운스 효과로 인해 마이너스가 되는 것을 방지(모바일)
currentScene--;
document.body.setAttribute('id', `show-scene-${currentScene}`);
}
if(enterNewScene === true) return;
playAnimation();
}
window.addEventListener('load', setLayout);
window.addEventListener('resize', setLayout);
window.addEventListener('scroll', () => {
yOffset = window.pageYOffset;
scrollLoop();
});
}) ();