Function init

js/impress.js:342–407

()

        // `init` API function that initializes (and runs) the presentation.
        var init = function() {
            if ( initialized ) { return; }

            // Initialize the configuration object, so it can be used by pre-init plugins.
            config = buildConfig();
            execPreInitPlugins( root );

            // First we set up the viewport for mobile devices.
            // For some reason iPad goes nuts when it is not done properly.
            var meta = lib.util.$( "meta[name='viewport']" ) || document.createElement( "meta" );
            meta.content = "width=device-width, minimum-scale=1, maximum-scale=1, user-scalable=no";
            if ( meta.parentNode !== document.head ) {
                meta.name = "viewport";
                document.head.appendChild( meta );
            }

            windowScale = computeWindowScale( config );

            // Wrap steps with "canvas" element
            lib.util.arrayify( root.childNodes ).forEach( function( el ) {
                canvas.appendChild( el );
            } );
            root.appendChild( canvas );

            // Set initial styles
            document.documentElement.style.height = "100%";

            css( body, {
                height: "100%",
                overflow: "hidden"
            } );

            var rootStyles = {
                position: "absolute",
                transformOrigin: "top left",
                transition: "all 0s ease-in-out",
                transformStyle: "preserve-3d"
            };

            css( root, rootStyles );
            css( root, {
                top: "50%",
                left: "50%",
                perspective: ( config.perspective / windowScale ) + "px",
                transform: scale( windowScale )
            } );
            css( canvas, rootStyles );

            body.classList.remove( "impress-disabled" );
            body.classList.add( "impress-enabled" );

            // Get and init steps
            initAllSteps();

            // Set a default initial state of the canvas
            currentState = {
                translate: { x: 0, y: 0, z: 0 },
                rotate:    { x: 0, y: 0, z: 0, order: "xyz" },