1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
|
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.
*/
async setupPDF() {
const config = this.Reveal.getConfig();
const slides = queryAll( this.Reveal.getRevealElement(), SLIDES_SELECTOR )
// Compute slide numbers now, before we start duplicating slides
const injectPageNumbers = config.slideNumber && /all|print/i.test( config.showSlideNumber );
const slideSize = this.Reveal.getComputedSlideSize( window.innerWidth, window.innerHeight );
// Dimensions of the PDF pages
const pageWidth = Math.floor( slideSize.width * ( 1 + config.margin ) ),
pageHeight = Math.floor( slideSize.height * ( 1 + config.margin ) );
// Dimensions of slides within the pages
const slideWidth = slideSize.width,
slideHeight = slideSize.height;
await new Promise( requestAnimationFrame );
// 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';
const viewportElement = document.querySelector( '.reveal-viewport' );
let presentationBackground;
if( viewportElement ) {
const viewportStyles = window.getComputedStyle( viewportElement );
if( viewportStyles && viewportStyles.background ) {
presentationBackground = viewportStyles.background;
}
}
// Make sure stretch elements fit on slide
await new Promise( requestAnimationFrame );
this.Reveal.layoutSlideContents( slideWidth, slideHeight );
// Batch scrollHeight access to prevent layout thrashing
await new Promise( requestAnimationFrame );
const slideScrollHeights = slides.map( slide => slide.scrollHeight );
const pages = [];
const pageContainer = slides[0].parentNode;
let slideNumber = 1;
// Slide and slide background layout
slides.forEach( function( slide, index ) {
// 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;
let top = ( pageHeight - slideHeight ) / 2;
const contentHeight = slideScrollHeights[ index ];
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
const page = document.createElement( 'div' );
pages.push( page );
page.className = 'pdf-page';
page.style.height = ( ( pageHeight + config.pdfPageHeightOffset ) * numberOfPages ) + 'px';
// Copy the presentation-wide background to each individual
// page when printing
if( presentationBackground ) {
page.style.background = presentationBackground;
}
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';
this.Reveal.slideContent.layout( slide );
if( slide.slideBackgroundElement ) {
page.insertBefore( slide.slideBackgroundElement, slide );
}
// Inject notes if `showNotes` is enabled
if( config.showNotes ) {
// Are there notes for this slide?
const notes = this.Reveal.getSlideNotes( slide );
if( notes ) {
const notesSpacing = 8;
const notesLayout = typeof config.showNotes === 'string' ? config.showNotes : 'inline';
const 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' ) {
pages.push( notesElement );
}
else {
notesElement.style.left = notesSpacing + 'px';
notesElement.style.bottom = notesSpacing + 'px';
notesElement.style.width = ( pageWidth - notesSpacing*2 ) + 'px';
page.appendChild( notesElement );
}
}
}
// Inject page numbers if `slideNumbers` are enabled
if( injectPageNumbers ) {
const numberElement = document.createElement( 'div' );
numberElement.classList.add( 'slide-number' );
numberElement.classList.add( 'slide-number-pdf' );
numberElement.innerHTML = slideNumber++;
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.
const fragmentGroups = this.Reveal.fragments.sort( page.querySelectorAll( '.fragment' ), true );
let previousFragmentStep;
fragmentGroups.forEach( function( fragments, index ) {
// 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
const clonedPage = page.cloneNode( true );
// Inject unique page numbers for fragments
if( injectPageNumbers ) {
const numberElement = clonedPage.querySelector( '.slide-number-pdf' );
const fragmentNumber = index + 1;
numberElement.innerHTML += '.' + fragmentNumber;
}
pages.push( clonedPage );
previousFragmentStep = fragments;
}, 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 );
await new Promise( requestAnimationFrame );
pages.forEach( page => pageContainer.appendChild( page ) );
// Re-run JS-based content layout after the slide is added to page DOM
this.Reveal.slideContent.layout( this.Reveal.getSlidesElement() );
// 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 );
}
}
|
