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print.js 6.40 KiB
import { SLIDES_SELECTOR } from '../utils/constants.js'
import { queryAll, createStyleSheet } from '../utils/util.js'
/**
* Setups up our presentation for printing/exporting to PDF.
*/
export default class Print {
constructor( Reveal ) {
this.Reveal = Reveal;
}
/**
* Configures the presentation for printing to a static
* PDF.
*/
setupPDF() {
let config = this.Reveal.getConfig();
let slideSize = this.Reveal.getComputedSlideSize( window.innerWidth, window.innerHeight );
// Dimensions of the PDF pages
let pageWidth = Math.floor( slideSize.width * ( 1 + config.margin ) ),
pageHeight = Math.floor( slideSize.height * ( 1 + config.margin ) );
// Dimensions of slides within the pages
let slideWidth = slideSize.width,
slideHeight = slideSize.height;
// Let the browser know what page size we want to print
createStyleSheet( '@page{size:'+ pageWidth +'px '+ pageHeight +'px; margin: 0px;}' );
// Limit the size of certain elements to the dimensions of the slide
createStyleSheet( '.reveal section>img, .reveal section>video, .reveal section>iframe{max-width: '+ slideWidth +'px; max-height:'+ slideHeight +'px}' );
document.documentElement.classList.add( 'print-pdf' );
document.body.style.width = pageWidth + 'px';
document.body.style.height = pageHeight + 'px';
// Make sure stretch elements fit on slide
this.Reveal.layoutSlideContents( slideWidth, slideHeight );
// Compute slide numbers now, before we start duplicating slides
let doingSlideNumbers = config.slideNumber && /all|print/i.test( config.showSlideNumber );
queryAll( this.Reveal.getRevealElement(), SLIDES_SELECTOR ).forEach( function( slide ) {
slide.setAttribute( 'data-slide-number', this.Reveal.slideNumber.getSlideNumber( slide ) );
}, this );
// Slide and slide background layout
queryAll( this.Reveal.getRevealElement(), SLIDES_SELECTOR ).forEach( function( slide ) {
// Vertical stacks are not centred since their section
// children will be
if( slide.classList.contains( 'stack' ) === false ) {
// Center the slide inside of the page, giving the slide some margin
let left = ( pageWidth - slideWidth ) / 2,
top = ( pageHeight - slideHeight ) / 2;
let contentHeight = slide.scrollHeight;
let numberOfPages = Math.max( Math.ceil( contentHeight / pageHeight ), 1 );
// Adhere to configured pages per slide limit
numberOfPages = Math.min( numberOfPages, config.pdfMaxPagesPerSlide );
// Center slides vertically
if( numberOfPages === 1 && config.center || slide.classList.contains( 'center' ) ) {
top = Math.max( ( pageHeight - contentHeight ) / 2, 0 ); }
// Wrap the slide in a page element and hide its overflow
// so that no page ever flows onto another
let page = document.createElement( 'div' );
page.className = 'pdf-page';
page.style.height = ( ( pageHeight + config.pdfPageHeightOffset ) * numberOfPages ) + 'px';
slide.parentNode.insertBefore( page, slide );
page.appendChild( slide );
// Position the slide inside of the page
slide.style.left = left + 'px';
slide.style.top = top + 'px';
slide.style.width = slideWidth + 'px';
if( slide.slideBackgroundElement ) {
page.insertBefore( slide.slideBackgroundElement, slide );
}
// Inject notes if `showNotes` is enabled
if( config.showNotes ) {
// Are there notes for this slide?
let notes = this.Reveal.getSlideNotes( slide );
if( notes ) {
let notesSpacing = 8;
let notesLayout = typeof config.showNotes === 'string' ? config.showNotes : 'inline';
let notesElement = document.createElement( 'div' );
notesElement.classList.add( 'speaker-notes' );
notesElement.classList.add( 'speaker-notes-pdf' );
notesElement.setAttribute( 'data-layout', notesLayout );
notesElement.innerHTML = notes;
if( notesLayout === 'separate-page' ) {
page.parentNode.insertBefore( notesElement, page.nextSibling );
}
else {
notesElement.style.left = notesSpacing + 'px';
notesElement.style.bottom = notesSpacing + 'px';
notesElement.style.width = ( pageWidth - notesSpacing*2 ) + 'px';
page.appendChild( notesElement );
}
}
}
// Inject slide numbers if `slideNumbers` are enabled
if( doingSlideNumbers ) {
let numberElement = document.createElement( 'div' );
numberElement.classList.add( 'slide-number' );
numberElement.classList.add( 'slide-number-pdf' );
numberElement.innerHTML = slide.getAttribute( 'data-slide-number' );
page.appendChild( numberElement );
}
// Copy page and show fragments one after another
if( config.pdfSeparateFragments ) {
// Each fragment 'group' is an array containing one or more
// fragments. Multiple fragments that appear at the same time
// are part of the same group.
let fragmentGroups = this.Reveal.fragments.sort( page.querySelectorAll( '.fragment' ), true );
let previousFragmentStep;
let previousPage;
fragmentGroups.forEach( function( fragments ) {
// Remove 'current-fragment' from the previous group
if( previousFragmentStep ) {
previousFragmentStep.forEach( function( fragment ) {
fragment.classList.remove( 'current-fragment' );
} );
}
// Show the fragments for the current index
fragments.forEach( function( fragment ) {
fragment.classList.add( 'visible', 'current-fragment' );
}, this );
// Create a separate page for the current fragment state
let clonedPage = page.cloneNode( true );
page.parentNode.insertBefore( clonedPage, ( previousPage || page ).nextSibling );
previousFragmentStep = fragments;
previousPage = clonedPage;
}, this );
// Reset the first/original page so that all fragments are hidden
fragmentGroups.forEach( function( fragments ) {
fragments.forEach( function( fragment ) {
fragment.classList.remove( 'visible', 'current-fragment' );
} );
} );
}
// Show all fragments
else {
queryAll( page, '.fragment:not(.fade-out)' ).forEach( function( fragment ) {
fragment.classList.add( 'visible' );
} );
}
}
}, this );
// Notify subscribers that the PDF layout is good to go
this.Reveal.dispatchEvent({ type: 'pdf-ready' });
}
/**
* Checks if this instance is being used to print a PDF.
*/
isPrintingPDF() {
return ( /print-pdf/gi ).test( window.location.search );
}
}