fractal.js

// fractal
head.load([
	'./engine/ngine.js',
	'./engine/nsvg.js',
	'./engine/ncell.js',
	'./engine/npath.js',
	'./engine/nlink.js',
	'./engine/nnode.js',
	'./engine/colours.js'
]);
window.onload = function() {
	document.getElementById("core").onclick = showSvg;
}
function showSvg(evt) {
	// get <svg> document
	var svg = document.getElementById("core");

	// remove all script tags within svg document
	var scripts = svg.getElementsByTagName("script")
	for(var i = 0; i < scripts.length; i++) {
		scripts[i].parentNode.removeChild(scripts[i]);
	}

	// prettify output
	var serializer = new XMLSerializer();
	let svgPretty = xmlPretty(serializer.serializeToString(svg));

	// generate new svg file
	var svg_blob = new Blob(
		[svgPretty],
		{'type': "image/svg+xml"}
	);
	var svgUrl = URL.createObjectURL(svg_blob);

	// download svg image
	var downloadLink = document.createElement("a");
	downloadLink.href = svgUrl;
	downloadLink.download = "output.svg";
	document.body.appendChild(downloadLink);
	downloadLink.click();
	document.body.removeChild(downloadLink);
}
function xmlPretty(xml) {
        var reg = /(>)\s*(<)(\/*)/g; // updated Mar 30, 2015
        var wsexp = / *(.*) +\n/g;
        var contexp = /(<.+>)(.+\n)/g;
        xml = xml.replace(reg, '$1\n$2$3').replace(wsexp, '$1\n').replace(contexp, '$1\n$2');
        var pad = 0;
        var formatted = '';
        var lines = xml.split('\n');
        var indent = 0;
        var lastType = 'other';
        // 4 types of tags - single, closing, opening, other (text, doctype, comment) - 4*4 = 16 transitions 
        var transitions = {
            'single->single': 0,
            'single->closing': -1,
            'single->opening': 0,
            'single->other': 0,
            'closing->single': 0,
            'closing->closing': -1,
            'closing->opening': 0,
            'closing->other': 0,
            'opening->single': 1,
            'opening->closing': 0,
            'opening->opening': 1,
            'opening->other': 1,
            'other->single': 0,
            'other->closing': -1,
            'other->opening': 0,
            'other->other': 0
        };

        for (var i = 0; i < lines.length; i++) {
            var ln = lines[i];

            // Luca Viggiani 2017-07-03: handle optional <?xml ... ?> declaration
            if (ln.match(/\s*<\?xml/)) {
                formatted += ln + "\n";
                continue;
            }
            // ---

            var single = Boolean(ln.match(/<.+\/>/)); // is this line a single tag? ex. <br />
            var closing = Boolean(ln.match(/<\/.+>/)); // is this a closing tag? ex. </a>
            var opening = Boolean(ln.match(/<[^!].*>/)); // is this even a tag (that's not <!something>)
            var type = single ? 'single' : closing ? 'closing' : opening ? 'opening' : 'other';
            var fromTo = lastType + '->' + type;
            lastType = type;
            var padding = '';

            indent += transitions[fromTo];
            for (var j = 0; j < indent; j++) {
                padding += '\t';
            }
            if (fromTo == 'opening->closing')
                formatted = formatted.substr(0, formatted.length - 1) + ln + '\n'; // substr removes line break (\n) from prev loop
            else
                formatted += padding + ln + '\n';
        }

        return formatted;
}