438 lines
14 KiB
JavaScript
438 lines
14 KiB
JavaScript
import { queryAll } from '../utils/util.js'
|
|
import { colorToRgb, colorBrightness } from '../utils/color.js'
|
|
|
|
/**
|
|
* Creates and updates slide backgrounds.
|
|
*/
|
|
export default class Backgrounds {
|
|
|
|
constructor( Reveal ) {
|
|
|
|
this.Reveal = Reveal;
|
|
|
|
}
|
|
|
|
render() {
|
|
|
|
this.element = document.createElement( 'div' );
|
|
this.element.className = 'backgrounds';
|
|
this.Reveal.getRevealElement().appendChild( this.element );
|
|
|
|
}
|
|
|
|
/**
|
|
* Creates the slide background elements and appends them
|
|
* to the background container. One element is created per
|
|
* slide no matter if the given slide has visible background.
|
|
*/
|
|
create() {
|
|
|
|
// Clear prior backgrounds
|
|
this.element.innerHTML = '';
|
|
this.element.classList.add( 'no-transition' );
|
|
|
|
// Iterate over all horizontal slides
|
|
this.Reveal.getHorizontalSlides().forEach( slideh => {
|
|
|
|
let backgroundStack = this.createBackground( slideh, this.element );
|
|
|
|
// Iterate over all vertical slides
|
|
queryAll( slideh, 'section' ).forEach( slidev => {
|
|
|
|
this.createBackground( slidev, backgroundStack );
|
|
|
|
backgroundStack.classList.add( 'stack' );
|
|
|
|
} );
|
|
|
|
} );
|
|
|
|
// Add parallax background if specified
|
|
if( this.Reveal.getConfig().parallaxBackgroundImage ) {
|
|
|
|
this.element.style.backgroundImage = 'url("' + this.Reveal.getConfig().parallaxBackgroundImage + '")';
|
|
this.element.style.backgroundSize = this.Reveal.getConfig().parallaxBackgroundSize;
|
|
this.element.style.backgroundRepeat = this.Reveal.getConfig().parallaxBackgroundRepeat;
|
|
this.element.style.backgroundPosition = this.Reveal.getConfig().parallaxBackgroundPosition;
|
|
|
|
// Make sure the below properties are set on the element - these properties are
|
|
// needed for proper transitions to be set on the element via CSS. To remove
|
|
// annoying background slide-in effect when the presentation starts, apply
|
|
// these properties after short time delay
|
|
setTimeout( () => {
|
|
this.Reveal.getRevealElement().classList.add( 'has-parallax-background' );
|
|
}, 1 );
|
|
|
|
}
|
|
else {
|
|
|
|
this.element.style.backgroundImage = '';
|
|
this.Reveal.getRevealElement().classList.remove( 'has-parallax-background' );
|
|
|
|
}
|
|
|
|
}
|
|
|
|
/**
|
|
* Creates a background for the given slide.
|
|
*
|
|
* @param {HTMLElement} slide
|
|
* @param {HTMLElement} container The element that the background
|
|
* should be appended to
|
|
* @return {HTMLElement} New background div
|
|
*/
|
|
createBackground( slide, container ) {
|
|
|
|
// Main slide background element
|
|
let element = document.createElement( 'div' );
|
|
element.className = 'slide-background ' + slide.className.replace( /present|past|future/, '' );
|
|
|
|
// Inner background element that wraps images/videos/iframes
|
|
let contentElement = document.createElement( 'div' );
|
|
contentElement.className = 'slide-background-content';
|
|
|
|
element.appendChild( contentElement );
|
|
container.appendChild( element );
|
|
|
|
slide.slideBackgroundElement = element;
|
|
slide.slideBackgroundContentElement = contentElement;
|
|
|
|
// Syncs the background to reflect all current background settings
|
|
this.sync( slide );
|
|
|
|
return element;
|
|
|
|
}
|
|
|
|
/**
|
|
* Renders all of the visual properties of a slide background
|
|
* based on the various background attributes.
|
|
*
|
|
* @param {HTMLElement} slide
|
|
*/
|
|
sync( slide ) {
|
|
|
|
const element = slide.slideBackgroundElement,
|
|
contentElement = slide.slideBackgroundContentElement;
|
|
|
|
const data = {
|
|
background: slide.getAttribute( 'data-background' ),
|
|
backgroundSize: slide.getAttribute( 'data-background-size' ),
|
|
backgroundImage: slide.getAttribute( 'data-background-image' ),
|
|
backgroundVideo: slide.getAttribute( 'data-background-video' ),
|
|
backgroundIframe: slide.getAttribute( 'data-background-iframe' ),
|
|
backgroundColor: slide.getAttribute( 'data-background-color' ),
|
|
backgroundGradient: slide.getAttribute( 'data-background-gradient' ),
|
|
backgroundRepeat: slide.getAttribute( 'data-background-repeat' ),
|
|
backgroundPosition: slide.getAttribute( 'data-background-position' ),
|
|
backgroundTransition: slide.getAttribute( 'data-background-transition' ),
|
|
backgroundOpacity: slide.getAttribute( 'data-background-opacity' ),
|
|
};
|
|
|
|
const dataPreload = slide.hasAttribute( 'data-preload' );
|
|
|
|
// Reset the prior background state in case this is not the
|
|
// initial sync
|
|
slide.classList.remove( 'has-dark-background' );
|
|
slide.classList.remove( 'has-light-background' );
|
|
|
|
element.removeAttribute( 'data-loaded' );
|
|
element.removeAttribute( 'data-background-hash' );
|
|
element.removeAttribute( 'data-background-size' );
|
|
element.removeAttribute( 'data-background-transition' );
|
|
element.style.backgroundColor = '';
|
|
|
|
contentElement.style.backgroundSize = '';
|
|
contentElement.style.backgroundRepeat = '';
|
|
contentElement.style.backgroundPosition = '';
|
|
contentElement.style.backgroundImage = '';
|
|
contentElement.style.opacity = '';
|
|
contentElement.innerHTML = '';
|
|
|
|
if( data.background ) {
|
|
// Auto-wrap image urls in url(...)
|
|
if( /^(http|file|\/\/)/gi.test( data.background ) || /\.(svg|png|jpg|jpeg|gif|bmp|webp)([?#\s]|$)/gi.test( data.background ) ) {
|
|
slide.setAttribute( 'data-background-image', data.background );
|
|
}
|
|
else {
|
|
element.style.background = data.background;
|
|
}
|
|
}
|
|
|
|
// Create a hash for this combination of background settings.
|
|
// This is used to determine when two slide backgrounds are
|
|
// the same.
|
|
if( data.background || data.backgroundColor || data.backgroundGradient || data.backgroundImage || data.backgroundVideo || data.backgroundIframe ) {
|
|
element.setAttribute( 'data-background-hash', data.background +
|
|
data.backgroundSize +
|
|
data.backgroundImage +
|
|
data.backgroundVideo +
|
|
data.backgroundIframe +
|
|
data.backgroundColor +
|
|
data.backgroundGradient +
|
|
data.backgroundRepeat +
|
|
data.backgroundPosition +
|
|
data.backgroundTransition +
|
|
data.backgroundOpacity );
|
|
}
|
|
|
|
// Additional and optional background properties
|
|
if( data.backgroundSize ) element.setAttribute( 'data-background-size', data.backgroundSize );
|
|
if( data.backgroundColor ) element.style.backgroundColor = data.backgroundColor;
|
|
if( data.backgroundGradient ) element.style.backgroundImage = data.backgroundGradient;
|
|
if( data.backgroundTransition ) element.setAttribute( 'data-background-transition', data.backgroundTransition );
|
|
|
|
if( dataPreload ) element.setAttribute( 'data-preload', '' );
|
|
|
|
// Background image options are set on the content wrapper
|
|
if( data.backgroundSize ) contentElement.style.backgroundSize = data.backgroundSize;
|
|
if( data.backgroundRepeat ) contentElement.style.backgroundRepeat = data.backgroundRepeat;
|
|
if( data.backgroundPosition ) contentElement.style.backgroundPosition = data.backgroundPosition;
|
|
if( data.backgroundOpacity ) contentElement.style.opacity = data.backgroundOpacity;
|
|
|
|
const contrastClass = this.getContrastClass( slide );
|
|
|
|
if( typeof contrastClass === 'string' ) {
|
|
slide.classList.add( contrastClass );
|
|
}
|
|
|
|
}
|
|
|
|
/**
|
|
* Returns a class name that can be applied to a slide to indicate
|
|
* if it has a light or dark background.
|
|
*
|
|
* @param {*} slide
|
|
*
|
|
* @returns {string|null}
|
|
*/
|
|
getContrastClass( slide ) {
|
|
|
|
const element = slide.slideBackgroundElement;
|
|
|
|
// If this slide has a background color, we add a class that
|
|
// signals if it is light or dark. If the slide has no background
|
|
// color, no class will be added
|
|
let contrastColor = slide.getAttribute( 'data-background-color' );
|
|
|
|
// If no bg color was found, or it cannot be converted by colorToRgb, check the computed background
|
|
if( !contrastColor || !colorToRgb( contrastColor ) ) {
|
|
let computedBackgroundStyle = window.getComputedStyle( element );
|
|
if( computedBackgroundStyle && computedBackgroundStyle.backgroundColor ) {
|
|
contrastColor = computedBackgroundStyle.backgroundColor;
|
|
}
|
|
}
|
|
|
|
if( contrastColor ) {
|
|
const rgb = colorToRgb( contrastColor );
|
|
|
|
// Ignore fully transparent backgrounds. Some browsers return
|
|
// rgba(0,0,0,0) when reading the computed background color of
|
|
// an element with no background
|
|
if( rgb && rgb.a !== 0 ) {
|
|
if( colorBrightness( contrastColor ) < 128 ) {
|
|
return 'has-dark-background';
|
|
}
|
|
else {
|
|
return 'has-light-background';
|
|
}
|
|
}
|
|
}
|
|
|
|
return null;
|
|
|
|
}
|
|
|
|
/**
|
|
* Bubble the 'has-light-background'/'has-dark-background' classes.
|
|
*/
|
|
bubbleSlideContrastClassToElement( slide, target ) {
|
|
|
|
[ 'has-light-background', 'has-dark-background' ].forEach( classToBubble => {
|
|
if( slide.classList.contains( classToBubble ) ) {
|
|
target.classList.add( classToBubble );
|
|
}
|
|
else {
|
|
target.classList.remove( classToBubble );
|
|
}
|
|
}, this );
|
|
|
|
}
|
|
|
|
/**
|
|
* Updates the background elements to reflect the current
|
|
* slide.
|
|
*
|
|
* @param {boolean} includeAll If true, the backgrounds of
|
|
* all vertical slides (not just the present) will be updated.
|
|
*/
|
|
update( includeAll = false ) {
|
|
|
|
let currentSlide = this.Reveal.getCurrentSlide();
|
|
let indices = this.Reveal.getIndices();
|
|
|
|
let currentBackground = null;
|
|
|
|
// Reverse past/future classes when in RTL mode
|
|
let horizontalPast = this.Reveal.getConfig().rtl ? 'future' : 'past',
|
|
horizontalFuture = this.Reveal.getConfig().rtl ? 'past' : 'future';
|
|
|
|
// Update the classes of all backgrounds to match the
|
|
// states of their slides (past/present/future)
|
|
Array.from( this.element.childNodes ).forEach( ( backgroundh, h ) => {
|
|
|
|
backgroundh.classList.remove( 'past', 'present', 'future' );
|
|
|
|
if( h < indices.h ) {
|
|
backgroundh.classList.add( horizontalPast );
|
|
}
|
|
else if ( h > indices.h ) {
|
|
backgroundh.classList.add( horizontalFuture );
|
|
}
|
|
else {
|
|
backgroundh.classList.add( 'present' );
|
|
|
|
// Store a reference to the current background element
|
|
currentBackground = backgroundh;
|
|
}
|
|
|
|
if( includeAll || h === indices.h ) {
|
|
queryAll( backgroundh, '.slide-background' ).forEach( ( backgroundv, v ) => {
|
|
|
|
backgroundv.classList.remove( 'past', 'present', 'future' );
|
|
|
|
if( v < indices.v ) {
|
|
backgroundv.classList.add( 'past' );
|
|
}
|
|
else if ( v > indices.v ) {
|
|
backgroundv.classList.add( 'future' );
|
|
}
|
|
else {
|
|
backgroundv.classList.add( 'present' );
|
|
|
|
// Only if this is the present horizontal and vertical slide
|
|
if( h === indices.h ) currentBackground = backgroundv;
|
|
}
|
|
|
|
} );
|
|
}
|
|
|
|
} );
|
|
|
|
// Stop content inside of previous backgrounds
|
|
if( this.previousBackground ) {
|
|
|
|
this.Reveal.slideContent.stopEmbeddedContent( this.previousBackground, { unloadIframes: !this.Reveal.slideContent.shouldPreload( this.previousBackground ) } );
|
|
|
|
}
|
|
|
|
// Start content in the current background
|
|
if( currentBackground ) {
|
|
|
|
this.Reveal.slideContent.startEmbeddedContent( currentBackground );
|
|
|
|
let currentBackgroundContent = currentBackground.querySelector( '.slide-background-content' );
|
|
if( currentBackgroundContent ) {
|
|
|
|
let backgroundImageURL = currentBackgroundContent.style.backgroundImage || '';
|
|
|
|
// Restart GIFs (doesn't work in Firefox)
|
|
if( /\.gif/i.test( backgroundImageURL ) ) {
|
|
currentBackgroundContent.style.backgroundImage = '';
|
|
window.getComputedStyle( currentBackgroundContent ).opacity;
|
|
currentBackgroundContent.style.backgroundImage = backgroundImageURL;
|
|
}
|
|
|
|
}
|
|
|
|
// Don't transition between identical backgrounds. This
|
|
// prevents unwanted flicker.
|
|
let previousBackgroundHash = this.previousBackground ? this.previousBackground.getAttribute( 'data-background-hash' ) : null;
|
|
let currentBackgroundHash = currentBackground.getAttribute( 'data-background-hash' );
|
|
if( currentBackgroundHash && currentBackgroundHash === previousBackgroundHash && currentBackground !== this.previousBackground ) {
|
|
this.element.classList.add( 'no-transition' );
|
|
}
|
|
|
|
this.previousBackground = currentBackground;
|
|
|
|
}
|
|
|
|
// If there's a background brightness flag for this slide,
|
|
// bubble it to the .reveal container
|
|
if( currentSlide ) {
|
|
this.bubbleSlideContrastClassToElement( currentSlide, this.Reveal.getRevealElement() );
|
|
}
|
|
|
|
// Allow the first background to apply without transition
|
|
setTimeout( () => {
|
|
this.element.classList.remove( 'no-transition' );
|
|
}, 1 );
|
|
|
|
}
|
|
|
|
/**
|
|
* Updates the position of the parallax background based
|
|
* on the current slide index.
|
|
*/
|
|
updateParallax() {
|
|
|
|
let indices = this.Reveal.getIndices();
|
|
|
|
if( this.Reveal.getConfig().parallaxBackgroundImage ) {
|
|
|
|
let horizontalSlides = this.Reveal.getHorizontalSlides(),
|
|
verticalSlides = this.Reveal.getVerticalSlides();
|
|
|
|
let backgroundSize = this.element.style.backgroundSize.split( ' ' ),
|
|
backgroundWidth, backgroundHeight;
|
|
|
|
if( backgroundSize.length === 1 ) {
|
|
backgroundWidth = backgroundHeight = parseInt( backgroundSize[0], 10 );
|
|
}
|
|
else {
|
|
backgroundWidth = parseInt( backgroundSize[0], 10 );
|
|
backgroundHeight = parseInt( backgroundSize[1], 10 );
|
|
}
|
|
|
|
let slideWidth = this.element.offsetWidth,
|
|
horizontalSlideCount = horizontalSlides.length,
|
|
horizontalOffsetMultiplier,
|
|
horizontalOffset;
|
|
|
|
if( typeof this.Reveal.getConfig().parallaxBackgroundHorizontal === 'number' ) {
|
|
horizontalOffsetMultiplier = this.Reveal.getConfig().parallaxBackgroundHorizontal;
|
|
}
|
|
else {
|
|
horizontalOffsetMultiplier = horizontalSlideCount > 1 ? ( backgroundWidth - slideWidth ) / ( horizontalSlideCount-1 ) : 0;
|
|
}
|
|
|
|
horizontalOffset = horizontalOffsetMultiplier * indices.h * -1;
|
|
|
|
let slideHeight = this.element.offsetHeight,
|
|
verticalSlideCount = verticalSlides.length,
|
|
verticalOffsetMultiplier,
|
|
verticalOffset;
|
|
|
|
if( typeof this.Reveal.getConfig().parallaxBackgroundVertical === 'number' ) {
|
|
verticalOffsetMultiplier = this.Reveal.getConfig().parallaxBackgroundVertical;
|
|
}
|
|
else {
|
|
verticalOffsetMultiplier = ( backgroundHeight - slideHeight ) / ( verticalSlideCount-1 );
|
|
}
|
|
|
|
verticalOffset = verticalSlideCount > 0 ? verticalOffsetMultiplier * indices.v : 0;
|
|
|
|
this.element.style.backgroundPosition = horizontalOffset + 'px ' + -verticalOffset + 'px';
|
|
|
|
}
|
|
|
|
}
|
|
|
|
destroy() {
|
|
|
|
this.element.remove();
|
|
|
|
}
|
|
|
|
}
|