in js/controllers/slidecontent.js [386:423]
startEmbeddedIframe( event ) {
let iframe = event.target;
if( iframe && iframe.contentWindow ) {
let isAttachedToDOM = !!closest( event.target, 'html' ),
isVisible = !!closest( event.target, '.present' );
if( isAttachedToDOM && isVisible ) {
// Prefer an explicit global autoplay setting
let autoplay = this.Reveal.getConfig().autoPlayMedia;
// If no global setting is available, fall back on the element's
// own autoplay setting
if( typeof autoplay !== 'boolean' ) {
autoplay = iframe.hasAttribute( 'data-autoplay' ) || !!closest( iframe, '.slide-background' );
}
// YouTube postMessage API
if( /youtube\.com\/embed\//.test( iframe.getAttribute( 'src' ) ) && autoplay ) {
iframe.contentWindow.postMessage( '{"event":"command","func":"playVideo","args":""}', '*' );
}
// Vimeo postMessage API
else if( /player\.vimeo\.com\//.test( iframe.getAttribute( 'src' ) ) && autoplay ) {
iframe.contentWindow.postMessage( '{"method":"play"}', '*' );
}
// Generic postMessage API
else {
iframe.contentWindow.postMessage( 'slide:start', '*' );
}
}
}
}