920 lines
26 KiB
JavaScript
920 lines
26 KiB
JavaScript
import { HORIZONTAL_SLIDES_SELECTOR, HORIZONTAL_BACKGROUNDS_SELECTOR } from '../utils/constants.js'
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import { queryAll } from '../utils/util.js'
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const HIDE_SCROLLBAR_TIMEOUT = 500;
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const MAX_PROGRESS_SPACING = 4;
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const MIN_PROGRESS_SEGMENT_HEIGHT = 6;
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const MIN_PLAYHEAD_HEIGHT = 8;
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/**
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* The scroll view lets you read a reveal.js presentation
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* as a linear scrollable page.
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*/
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export default class ScrollView {
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constructor( Reveal ) {
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this.Reveal = Reveal;
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this.active = false;
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this.activatedCallbacks = [];
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this.onScroll = this.onScroll.bind( this );
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}
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/**
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* Activates the scroll view. This rearranges the presentation DOM
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* by—among other things—wrapping each slide in a page element.
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*/
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activate() {
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if( this.active ) return;
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const stateBeforeActivation = this.Reveal.getState();
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this.active = true;
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// Store the full presentation HTML so that we can restore it
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// when/if the scroll view is deactivated
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this.slideHTMLBeforeActivation = this.Reveal.getSlidesElement().innerHTML;
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const horizontalSlides = queryAll( this.Reveal.getRevealElement(), HORIZONTAL_SLIDES_SELECTOR );
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const horizontalBackgrounds = queryAll( this.Reveal.getRevealElement(), HORIZONTAL_BACKGROUNDS_SELECTOR );
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this.viewportElement.classList.add( 'loading-scroll-mode', 'reveal-scroll' );
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let presentationBackground;
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const viewportStyles = window.getComputedStyle( this.viewportElement );
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if( viewportStyles && viewportStyles.background ) {
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presentationBackground = viewportStyles.background;
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}
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const pageElements = [];
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const pageContainer = horizontalSlides[0].parentNode;
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let previousSlide;
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// Creates a new page element and appends the given slide/bg
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// to it.
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const createPageElement = ( slide, h, v, isVertical ) => {
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let contentContainer;
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// If this slide is part of an auto-animation sequence, we
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// group it under the same page element as the previous slide
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if( previousSlide && this.Reveal.shouldAutoAnimateBetween( previousSlide, slide ) ) {
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contentContainer = document.createElement( 'div' );
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contentContainer.className = 'scroll-page-content scroll-auto-animate-page';
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contentContainer.style.display = 'none';
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previousSlide.closest( '.scroll-page-content' ).parentNode.appendChild( contentContainer );
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}
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else {
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// Wrap the slide in a page element and hide its overflow
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// so that no page ever flows onto another
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const page = document.createElement( 'div' );
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page.className = 'scroll-page';
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pageElements.push( page );
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// This transfers over the background of the vertical stack containing
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// the slide if it exists. Otherwise, it uses the presentation-wide
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// background.
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if( isVertical && horizontalBackgrounds.length > h ) {
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const slideBackground = horizontalBackgrounds[h];
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const pageBackground = window.getComputedStyle( slideBackground );
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if( pageBackground && pageBackground.background ) {
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page.style.background = pageBackground.background;
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}
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else if( presentationBackground ) {
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page.style.background = presentationBackground;
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}
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} else if( presentationBackground ) {
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page.style.background = presentationBackground;
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}
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const stickyContainer = document.createElement( 'div' );
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stickyContainer.className = 'scroll-page-sticky';
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page.appendChild( stickyContainer );
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contentContainer = document.createElement( 'div' );
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contentContainer.className = 'scroll-page-content';
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stickyContainer.appendChild( contentContainer );
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}
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contentContainer.appendChild( slide );
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slide.classList.remove( 'past', 'future' );
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slide.setAttribute( 'data-index-h', h );
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slide.setAttribute( 'data-index-v', v );
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if( slide.slideBackgroundElement ) {
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slide.slideBackgroundElement.remove( 'past', 'future' );
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contentContainer.insertBefore( slide.slideBackgroundElement, slide );
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}
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previousSlide = slide;
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}
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// Slide and slide background layout
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horizontalSlides.forEach( ( horizontalSlide, h ) => {
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if( this.Reveal.isVerticalStack( horizontalSlide ) ) {
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horizontalSlide.querySelectorAll( 'section' ).forEach( ( verticalSlide, v ) => {
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createPageElement( verticalSlide, h, v, true );
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});
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}
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else {
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createPageElement( horizontalSlide, h, 0 );
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}
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}, this );
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this.createProgressBar();
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// Remove leftover stacks
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queryAll( this.Reveal.getRevealElement(), '.stack' ).forEach( stack => stack.remove() );
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// Add our newly created pages to the DOM
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pageElements.forEach( page => pageContainer.appendChild( page ) );
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// Re-run JS-based content layout after the slide is added to page DOM
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this.Reveal.slideContent.layout( this.Reveal.getSlidesElement() );
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this.Reveal.layout();
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this.Reveal.setState( stateBeforeActivation );
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this.activatedCallbacks.forEach( callback => callback() );
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this.activatedCallbacks = [];
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this.restoreScrollPosition();
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this.viewportElement.classList.remove( 'loading-scroll-mode' );
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this.viewportElement.addEventListener( 'scroll', this.onScroll, { passive: true } );
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}
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/**
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* Deactivates the scroll view and restores the standard slide-based
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* presentation.
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*/
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deactivate() {
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if( !this.active ) return;
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const stateBeforeDeactivation = this.Reveal.getState();
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this.active = false;
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this.viewportElement.removeEventListener( 'scroll', this.onScroll );
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this.viewportElement.classList.remove( 'reveal-scroll' );
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this.removeProgressBar();
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this.Reveal.getSlidesElement().innerHTML = this.slideHTMLBeforeActivation;
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this.Reveal.sync();
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this.Reveal.setState( stateBeforeDeactivation );
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this.slideHTMLBeforeActivation = null;
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}
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toggle( override ) {
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if( typeof override === 'boolean' ) {
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override ? this.activate() : this.deactivate();
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}
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else {
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this.isActive() ? this.deactivate() : this.activate();
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}
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}
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/**
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* Checks if the scroll view is currently active.
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*/
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isActive() {
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return this.active;
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}
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/**
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* Renders the progress bar component.
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*/
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createProgressBar() {
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this.progressBar = document.createElement( 'div' );
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this.progressBar.className = 'scrollbar';
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this.progressBarInner = document.createElement( 'div' );
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this.progressBarInner.className = 'scrollbar-inner';
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this.progressBar.appendChild( this.progressBarInner );
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this.progressBarPlayhead = document.createElement( 'div' );
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this.progressBarPlayhead.className = 'scrollbar-playhead';
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this.progressBarInner.appendChild( this.progressBarPlayhead );
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this.viewportElement.insertBefore( this.progressBar, this.viewportElement.firstChild );
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const handleDocumentMouseMove = ( event ) => {
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let progress = ( event.clientY - this.progressBarInner.getBoundingClientRect().top ) / this.progressBarHeight;
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progress = Math.max( Math.min( progress, 1 ), 0 );
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this.viewportElement.scrollTop = progress * ( this.viewportElement.scrollHeight - this.viewportElement.offsetHeight );
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};
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const handleDocumentMouseUp = ( event ) => {
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this.draggingProgressBar = false;
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this.showProgressBar();
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document.removeEventListener( 'mousemove', handleDocumentMouseMove );
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document.removeEventListener( 'mouseup', handleDocumentMouseUp );
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};
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const handleMouseDown = ( event ) => {
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event.preventDefault();
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this.draggingProgressBar = true;
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document.addEventListener( 'mousemove', handleDocumentMouseMove );
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document.addEventListener( 'mouseup', handleDocumentMouseUp );
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handleDocumentMouseMove( event );
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};
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this.progressBarInner.addEventListener( 'mousedown', handleMouseDown );
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}
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removeProgressBar() {
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if( this.progressBar ) {
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this.progressBar.remove();
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this.progressBar = null;
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}
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}
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layout() {
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if( this.isActive() ) {
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this.syncPages();
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this.syncScrollPosition();
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}
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}
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/**
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* Updates our pages to match the latest configuration and
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* presentation size.
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*/
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syncPages() {
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const config = this.Reveal.getConfig();
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const slideSize = this.Reveal.getComputedSlideSize( window.innerWidth, window.innerHeight );
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const scale = this.Reveal.getScale();
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const useCompactLayout = config.scrollLayout === 'compact';
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const viewportHeight = this.viewportElement.offsetHeight;
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const compactHeight = slideSize.height * scale;
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const pageHeight = useCompactLayout ? compactHeight : viewportHeight;
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// The height that needs to be scrolled between scroll triggers
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this.scrollTriggerHeight = useCompactLayout ? compactHeight : viewportHeight;
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this.viewportElement.style.setProperty( '--page-height', pageHeight + 'px' );
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this.viewportElement.style.scrollSnapType = typeof config.scrollSnap === 'string' ? `y ${config.scrollSnap}` : '';
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// This will hold all scroll triggers used to show/hide slides
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this.slideTriggers = [];
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const pageElements = Array.from( this.Reveal.getRevealElement().querySelectorAll( '.scroll-page' ) );
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this.pages = pageElements.map( pageElement => {
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const page = this.createPage({
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pageElement,
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slideElement: pageElement.querySelector( 'section' ),
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stickyElement: pageElement.querySelector( '.scroll-page-sticky' ),
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contentElement: pageElement.querySelector( '.scroll-page-content' ),
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backgroundElement: pageElement.querySelector( '.slide-background' ),
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autoAnimateElements: pageElement.querySelectorAll( '.scroll-auto-animate-page' ),
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autoAnimatePages: []
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});
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page.pageElement.style.setProperty( '--slide-height', config.center === true ? 'auto' : slideSize.height + 'px' );
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this.slideTriggers.push({
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page: page,
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activate: () => this.activatePage( page ),
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deactivate: () => this.deactivatePage( page )
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});
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// Create scroll triggers that show/hide fragments
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this.createFragmentTriggersForPage( page );
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// Create scroll triggers for triggering auto-animate steps
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if( page.autoAnimateElements.length > 0 ) {
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this.createAutoAnimateTriggersForPage( page );
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}
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let totalScrollTriggerCount = Math.max( page.scrollTriggers.length - 1, 0 );
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// Each auto-animate step may include its own scroll triggers
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// for fragments, ensure we count those as well
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totalScrollTriggerCount += page.autoAnimatePages.reduce( ( total, page ) => {
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return total + Math.max( page.scrollTriggers.length - 1, 0 );
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}, page.autoAnimatePages.length );
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// Clean up from previous renders
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page.pageElement.querySelectorAll( '.scroll-snap-point' ).forEach( el => el.remove() );
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// Create snap points for all scroll triggers
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// - Can't be absolute in FF
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// - Can't be 0-height in Safari
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// - Can't use snap-align on parent in Safari because then
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// inner triggers won't work
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for( let i = 0; i < totalScrollTriggerCount + 1; i++ ) {
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const triggerStick = document.createElement( 'div' );
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triggerStick.className = 'scroll-snap-point';
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triggerStick.style.height = this.scrollTriggerHeight + 'px';
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triggerStick.style.scrollSnapAlign = useCompactLayout ? 'center' : 'start';
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page.pageElement.appendChild( triggerStick );
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if( i === 0 ) {
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triggerStick.style.marginTop = -this.scrollTriggerHeight + 'px';
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}
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}
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// In the compact layout, only slides with scroll triggers cover the
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// full viewport height. This helps avoid empty gaps before or after
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// a sticky slide.
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if( useCompactLayout && page.scrollTriggers.length > 0 ) {
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page.pageHeight = viewportHeight;
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page.pageElement.style.setProperty( '--page-height', viewportHeight + 'px' );
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}
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else {
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page.pageHeight = pageHeight;
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page.pageElement.style.removeProperty( '--page-height' );
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}
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// Add scroll padding based on how many scroll triggers we have
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page.scrollPadding = this.scrollTriggerHeight * totalScrollTriggerCount;
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// The total height including scrollable space
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page.totalHeight = page.pageHeight + page.scrollPadding;
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// This is used to pad the height of our page in CSS
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page.pageElement.style.setProperty( '--page-scroll-padding', page.scrollPadding + 'px' );
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// If this is a sticky page, stick it to the vertical center
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if( totalScrollTriggerCount > 0 ) {
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page.stickyElement.style.position = 'sticky';
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page.stickyElement.style.top = Math.max( ( viewportHeight - page.pageHeight ) / 2, 0 ) + 'px';
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}
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else {
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page.stickyElement.style.position = 'relative';
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page.pageElement.style.scrollSnapAlign = page.pageHeight < viewportHeight ? 'center' : 'start';
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}
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return page;
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} );
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this.setTriggerRanges();
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/*
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console.log(this.slideTriggers.map( t => {
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return {
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range: `${t.range[0].toFixed(2)}-${t.range[1].toFixed(2)}`,
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triggers: t.page.scrollTriggers.map( t => {
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return `${t.range[0].toFixed(2)}-${t.range[1].toFixed(2)}`
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}).join( ', ' ),
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}
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}))
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*/
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this.viewportElement.setAttribute( 'data-scrollbar', config.scrollProgress );
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if( config.scrollProgress && this.totalScrollTriggerCount > 1 ) {
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// Create the progress bar if it doesn't already exist
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if( !this.progressBar ) this.createProgressBar();
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this.syncProgressBar();
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}
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else {
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this.removeProgressBar();
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}
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}
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/**
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* Calculates and sets the scroll range for all of our scroll
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* triggers.
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*/
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setTriggerRanges() {
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// Calculate the total number of scroll triggers
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this.totalScrollTriggerCount = this.slideTriggers.reduce( ( total, trigger ) => {
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return total + Math.max( trigger.page.scrollTriggers.length, 1 );
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}, 0 );
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let rangeStart = 0;
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// Calculate the scroll range of each scroll trigger on a scale
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// of 0-1
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this.slideTriggers.forEach( ( trigger, i ) => {
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trigger.range = [
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rangeStart,
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rangeStart + Math.max( trigger.page.scrollTriggers.length, 1 ) / this.totalScrollTriggerCount
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];
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const scrollTriggerSegmentSize = ( trigger.range[1] - trigger.range[0] ) / trigger.page.scrollTriggers.length;
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// Set the range for each inner scroll trigger
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trigger.page.scrollTriggers.forEach( ( scrollTrigger, i ) => {
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scrollTrigger.range = [
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rangeStart + i * scrollTriggerSegmentSize,
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rangeStart + ( i + 1 ) * scrollTriggerSegmentSize
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];
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} );
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rangeStart = trigger.range[1];
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} );
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}
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/**
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* Creates one scroll trigger for each fragments in the given page.
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*
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* @param {*} page
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*/
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createFragmentTriggersForPage( page, slideElement ) {
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slideElement = slideElement || page.slideElement;
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// Each fragment 'group' is an array containing one or more
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// fragments. Multiple fragments that appear at the same time
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// are part of the same group.
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const fragmentGroups = this.Reveal.fragments.sort( slideElement.querySelectorAll( '.fragment' ), true );
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// Create scroll triggers that show/hide fragments
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if( fragmentGroups.length ) {
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page.fragments = this.Reveal.fragments.sort( slideElement.querySelectorAll( '.fragment:not(.disabled)' ) );
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page.scrollTriggers.push(
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// Trigger for the initial state with no fragments visible
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{
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activate: () => {
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this.Reveal.fragments.update( -1, page.fragments, slideElement );
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}
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}
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);
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// Triggers for each fragment group
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fragmentGroups.forEach( ( fragments, i ) => {
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page.scrollTriggers.push({
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activate: () => {
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this.Reveal.fragments.update( i, page.fragments, slideElement );
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}
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});
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} );
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}
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return page.scrollTriggers.length;
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}
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/**
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* Creates scroll triggers for the auto-animate steps in the
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* given page.
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*
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* @param {*} page
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*/
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createAutoAnimateTriggersForPage( page ) {
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if( page.autoAnimateElements.length > 0 ) {
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// Triggers for each subsequent auto-animate slide
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this.slideTriggers.push( ...Array.from( page.autoAnimateElements ).map( ( autoAnimateElement, i ) => {
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let autoAnimatePage = this.createPage({
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slideElement: autoAnimateElement.querySelector( 'section' ),
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contentElement: autoAnimateElement,
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backgroundElement: autoAnimateElement.querySelector( '.slide-background' )
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});
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// Create fragment scroll triggers for the auto-animate slide
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this.createFragmentTriggersForPage( autoAnimatePage, autoAnimatePage.slideElement );
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page.autoAnimatePages.push( autoAnimatePage );
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// Return our slide trigger
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return {
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page: autoAnimatePage,
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activate: () => this.activatePage( autoAnimatePage ),
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deactivate: () => this.deactivatePage( autoAnimatePage )
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};
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}));
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}
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}
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/**
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* Helper method for creating a page definition and adding
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* required fields. A "page" is a slide or auto-animate step.
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*/
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createPage( page ) {
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page.scrollTriggers = [];
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page.indexh = parseInt( page.slideElement.getAttribute( 'data-index-h' ), 10 );
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page.indexv = parseInt( page.slideElement.getAttribute( 'data-index-v' ), 10 );
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return page;
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}
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/**
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* Rerenders progress bar segments so that they match the current
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* reveal.js config and size.
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*/
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syncProgressBar() {
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this.progressBarInner.querySelectorAll( '.scrollbar-slide' ).forEach( slide => slide.remove() );
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const scrollHeight = this.viewportElement.scrollHeight;
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const viewportHeight = this.viewportElement.offsetHeight;
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const viewportHeightFactor = viewportHeight / scrollHeight;
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this.progressBarHeight = this.progressBarInner.offsetHeight;
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this.playheadHeight = Math.max( viewportHeightFactor * this.progressBarHeight, MIN_PLAYHEAD_HEIGHT );
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this.progressBarScrollableHeight = this.progressBarHeight - this.playheadHeight;
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const progressSegmentHeight = viewportHeight / scrollHeight * this.progressBarHeight;
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const spacing = Math.min( progressSegmentHeight / 8, MAX_PROGRESS_SPACING );
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this.progressBarPlayhead.style.height = this.playheadHeight - spacing + 'px';
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// Don't show individual segments if they're too small
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if( progressSegmentHeight > MIN_PROGRESS_SEGMENT_HEIGHT ) {
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this.slideTriggers.forEach( slideTrigger => {
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const { page } = slideTrigger;
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// Visual representation of a slide
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page.progressBarSlide = document.createElement( 'div' );
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page.progressBarSlide.className = 'scrollbar-slide';
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page.progressBarSlide.style.top = slideTrigger.range[0] * this.progressBarHeight + 'px';
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page.progressBarSlide.style.height = ( slideTrigger.range[1] - slideTrigger.range[0] ) * this.progressBarHeight - spacing + 'px';
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page.progressBarSlide.classList.toggle( 'has-triggers', page.scrollTriggers.length > 0 );
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this.progressBarInner.appendChild( page.progressBarSlide );
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// Visual representations of each scroll trigger
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page.scrollTriggerElements = page.scrollTriggers.map( ( trigger, i ) => {
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const triggerElement = document.createElement( 'div' );
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triggerElement.className = 'scrollbar-trigger';
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triggerElement.style.top = ( trigger.range[0] - slideTrigger.range[0] ) * this.progressBarHeight + 'px';
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triggerElement.style.height = ( trigger.range[1] - trigger.range[0] ) * this.progressBarHeight - spacing + 'px';
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page.progressBarSlide.appendChild( triggerElement );
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if( i === 0 ) triggerElement.style.display = 'none';
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return triggerElement;
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} );
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} );
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}
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else {
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this.pages.forEach( page => page.progressBarSlide = null );
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}
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}
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/**
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* Reads the current scroll position and updates our active
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* trigger states accordingly.
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*/
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syncScrollPosition() {
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const viewportHeight = this.viewportElement.offsetHeight;
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const viewportHeightFactor = viewportHeight / this.viewportElement.scrollHeight;
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const scrollTop = this.viewportElement.scrollTop;
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const scrollHeight = this.viewportElement.scrollHeight - viewportHeight
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const scrollProgress = Math.max( Math.min( scrollTop / scrollHeight, 1 ), 0 );
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const scrollProgressMid = Math.max( Math.min( ( scrollTop + viewportHeight / 2 ) / this.viewportElement.scrollHeight, 1 ), 0 );
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let activePage;
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this.slideTriggers.forEach( ( trigger ) => {
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const { page } = trigger;
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const shouldPreload = scrollProgress >= trigger.range[0] - viewportHeightFactor*2 &&
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scrollProgress <= trigger.range[1] + viewportHeightFactor*2;
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// Load slides that are within the preload range
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if( shouldPreload && !page.loaded ) {
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page.loaded = true;
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this.Reveal.slideContent.load( page.slideElement );
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}
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else if( page.loaded ) {
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page.loaded = false;
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this.Reveal.slideContent.unload( page.slideElement );
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}
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// If we're within this trigger range, activate it
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if( scrollProgress >= trigger.range[0] && scrollProgress <= trigger.range[1] ) {
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this.activateTrigger( trigger );
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activePage = trigger.page;
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}
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// .. otherwise deactivate
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else if( trigger.active ) {
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this.deactivateTrigger( trigger );
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}
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} );
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// Each page can have its own scroll triggers, check if any of those
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// need to be activated/deactivated
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if( activePage ) {
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activePage.scrollTriggers.forEach( ( trigger ) => {
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if( scrollProgressMid >= trigger.range[0] && scrollProgressMid <= trigger.range[1] ) {
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this.activateTrigger( trigger );
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}
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else if( trigger.active ) {
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this.deactivateTrigger( trigger );
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}
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} );
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}
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// Update our visual progress indication
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this.setProgressBarValue( scrollTop / ( this.viewportElement.scrollHeight - viewportHeight ) );
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}
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/**
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* Moves the progress bar playhead to the specified position.
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*
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* @param {number} progress 0-1
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*/
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setProgressBarValue( progress ) {
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if( this.progressBar ) {
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this.progressBarPlayhead.style.transform = `translateY(${progress * this.progressBarScrollableHeight}px)`;
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this.getAllPages()
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.filter( page => page.progressBarSlide )
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.forEach( ( page ) => {
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page.progressBarSlide.classList.toggle( 'active', page.active === true );
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page.scrollTriggers.forEach( ( trigger, i ) => {
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page.scrollTriggerElements[i].classList.toggle( 'active', page.active === true && trigger.active === true );
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} );
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} );
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this.showProgressBar();
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}
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}
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/**
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* Show the progress bar and, if configured, automatically hide
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* it after a delay.
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*/
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showProgressBar() {
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this.progressBar.classList.add( 'visible' );
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clearTimeout( this.hideProgressBarTimeout );
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if( this.Reveal.getConfig().scrollProgress === 'auto' && !this.draggingProgressBar ) {
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this.hideProgressBarTimeout = setTimeout( () => {
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if( this.progressBar ) {
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this.progressBar.classList.remove( 'visible' );
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}
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}, HIDE_SCROLLBAR_TIMEOUT );
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}
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}
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/**
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* Scroll to the previous page.
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*/
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prev() {
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this.viewportElement.scrollTop -= this.scrollTriggerHeight;
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}
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/**
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* Scroll to the next page.
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*/
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next() {
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this.viewportElement.scrollTop += this.scrollTriggerHeight;
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}
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/**
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* Scrolls the given slide element into view.
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*
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* @param {HTMLElement} slideElement
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*/
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scrollToSlide( slideElement ) {
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// If the scroll view isn't active yet, queue this action
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if( !this.active ) {
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this.activatedCallbacks.push( () => this.scrollToSlide( slideElement ) );
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}
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else {
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// Find the trigger for this slide
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const trigger = this.getScrollTriggerBySlide( slideElement );
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if( trigger ) {
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// Use the trigger's range to calculate the scroll position
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this.viewportElement.scrollTop = trigger.range[0] * ( this.viewportElement.scrollHeight - this.viewportElement.offsetHeight );
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}
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}
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}
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/**
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* Persists the current scroll position to session storage
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* so that it can be restored.
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*/
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storeScrollPosition() {
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clearTimeout( this.storeScrollPositionTimeout );
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this.storeScrollPositionTimeout = setTimeout( () => {
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sessionStorage.setItem( 'reveal-scroll-top', this.viewportElement.scrollTop );
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sessionStorage.setItem( 'reveal-scroll-origin', location.origin + location.pathname );
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this.storeScrollPositionTimeout = null;
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}, 50 );
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}
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/**
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* Restores the scroll position when a deck is reloader.
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*/
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restoreScrollPosition() {
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const scrollPosition = sessionStorage.getItem( 'reveal-scroll-top' );
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const scrollOrigin = sessionStorage.getItem( 'reveal-scroll-origin' );
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if( scrollPosition && scrollOrigin === location.origin + location.pathname ) {
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this.viewportElement.scrollTop = parseInt( scrollPosition, 10 );
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}
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}
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/**
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* Activates the given page and starts its embedded content
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* if there is any.
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*
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* @param {object} page
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*/
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activatePage( page ) {
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if( !page.active ) {
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page.active = true;
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const { slideElement, backgroundElement, contentElement, indexh, indexv } = page;
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contentElement.style.display = 'block';
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slideElement.classList.add( 'present' );
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if( backgroundElement ) {
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backgroundElement.classList.add( 'present' );
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}
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this.Reveal.setCurrentScrollPage( slideElement, indexh, indexv );
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this.Reveal.backgrounds.bubbleSlideContrastClassToElement( slideElement, this.viewportElement );
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// If this page is part of an auto-animation there will be one
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// content element per auto-animated page. We need to show the
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// current page and hide all others.
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Array.from( contentElement.parentNode.querySelectorAll( '.scroll-page-content' ) ).forEach( sibling => {
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if( sibling !== contentElement ) {
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sibling.style.display = 'none';
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}
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});
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}
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}
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/**
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* Deactivates the page after it has been visible.
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*
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* @param {object} page
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*/
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deactivatePage( page ) {
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if( page.active ) {
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page.active = false;
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if( page.slideElement ) page.slideElement.classList.remove( 'present' );
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if( page.backgroundElement ) page.backgroundElement.classList.remove( 'present' );
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}
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}
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activateTrigger( trigger ) {
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if( !trigger.active ) {
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trigger.active = true;
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trigger.activate();
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}
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}
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deactivateTrigger( trigger ) {
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if( trigger.active ) {
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trigger.active = false;
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if( trigger.deactivate ) {
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trigger.deactivate();
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}
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}
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}
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/**
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* Retrieve a slide by its original h/v index (i.e. the indices the
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* slide had before being linearized).
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*
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* @param {number} h
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* @param {number} v
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* @returns {HTMLElement}
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*/
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getSlideByIndices( h, v ) {
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const page = this.getAllPages().find( page => {
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return page.indexh === h && page.indexv === v;
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} );
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return page ? page.slideElement : null;
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}
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/**
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* Retrieve a list of all scroll triggers for the given slide
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* DOM element.
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*
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* @param {HTMLElement} slide
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* @returns {Array}
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*/
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getScrollTriggerBySlide( slide ) {
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return this.slideTriggers.find( trigger => trigger.page.slideElement === slide );
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}
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/**
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* Get a list of all pages in the scroll view. This includes
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* both top-level slides and auto-animate steps.
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*
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* @returns {Array}
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*/
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getAllPages() {
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return this.pages.flatMap( page => [page, ...(page.autoAnimatePages || [])] );
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}
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onScroll() {
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this.syncScrollPosition();
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this.storeScrollPosition();
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}
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get viewportElement() {
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return this.Reveal.getViewportElement();
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}
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}
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