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by anders30 3932 days ago
This is a wonderful tool for simple flow charting. I agree with other posters that a little more documentation would be nice and would also like to request the ability to export the underlying SVG (I'm still browsing source to see if that exists). I'm willing to help add both, thank you for this!
2 comments

The RaphaelJS library, which this is built on, doesn't have a built-in SVG exporter (though there is a limited functionality for that, along with SVG export plugins), but in FireFox and Chrome, these two lines will get you the <SVG/> export:

    var svg = document.getElementsByTagName("svg");
    var code = svg[0].outerHTML;
Of course, that assumes you're just getting the first SVG, etc and so on. Anyhow, this does NOT work on IE because IE hates innerHTML / outerHTML for SVG elements.

One tiny thing that stands out is that RaphaelJS is built to support even IE6, and yet this flowchart program seems to bork under IE.

Edit #2: forgot to mention, Raphael was specifically designed to fallback to VML if SVG is unavailable, so the export functionality would need to support both or pick and choose, or just reconstruct programmatically. A dilemma indeed.

You could use this to convert from SVG to a Canvas element and then from Canvas to an image (via canvas.toDataURL("image/png")):

https://github.com/gabelerner/canvg

Still needs a very newish browser however. No IE 6-8 (& 9?) support.

Yeah, it's a pickle. Raphael supports limited subset of SVG with VML failover compatibility, but export is limited because you have to support two technologies.

Then it gets weirder because RaphaelJS isn't exactly responsive-ready. Takes some work to make graphics just resizable (you can scale with the viewbox, but that's about it.) Recently, I switched to pure SVG (even when programmatically generated) because nested SVG elements provide basically a mechanism for relative/responsive scaling, positioning and such.

The guy who came up with RaphaelJS was ahead of his time, and I believe he got hired by Adobe in part thanks to the project's exposure. The development stopped awhile back, and it shows, which is really sad because I liked how the programming style for Raphael is done.

I would prefer the SVG itself but this is an ideal short term solution. Thank you very much!
I have written two ways of exporting SVG that you can inspect here: http://staticresource.com/sketch.html

One takes the SVG from the browser, encodes it and sends the <svg> as the body of an email (inlined, not as an attachment). Here's the relevant part:

    function render() {
      var link = document.createElement('a'),
          time = Date.now();
      link.href = 'mailto:?  subject=exported%20sketch&body=%3C%3Fxml%20version%3D%221.0%22%20standalone%3D%22no%22%3F%3E%3C!DOCTYPE%20svg%20PUBLIC%20%22-%2F%2FW3C%2F%2FDTD%20SVG%201.1%2F%2FEN%22%20%22http%3A%2F%2Fwww.w3.org%2FGraphics%2FSVG%2F1.1%2FDTD%2Fsvg11.dtd%22%3E'+encodeURIComponent(new XMLSerializer().serializeToString(board));
      link.id = time;
      document.body.appendChild(link);
      document.getElementById(time).dispatchEvent(new MouseEvent('click'));
      document.getElementById(time).parentNode.removeChild(document.getElementById(time));
    }
The other prepares it as a file and creates a download link (not seen on screen) and programmatically clicks that link to download it:

    function download() {
      var link = document.createElement('a'),
          time = Date.now(),
          svg = '<?xml version="1.0" standalone="no"?><!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">'+new XMLSerializer().serializeToString(board);
      link.id = time;
      link.setAttribute('download','sketch.svg');
      link.href = 'data:text/html;charset=utf-8,' + encodeURIComponent(svg);
      document.body.appendChild(link);
      document.getElementById(time).dispatchEvent(new MouseEvent('click'));
      document.getElementById(time).parentNode.removeChild(document.getElementById(time));
    }
But be forewarned, since SVG uses XML namespaces instead of HTML, using things like '.innerHTML' won't work in certain browsers (iOS Mobile Safari for example) while innerHTML does tend to work as you would expect on most desktop browsers!

Canvas would work for exporting a bitmapped snapshot of the vector, but lacks the following:

- filesize: SVG is vector, but Canvas renders a bitmap

- non-destructive: SVG is human-editable after the fact, bitmaps only 'remember' the value of the top-most pixel and 'forgets' everything that has overlapped

- human-editable: Though not pretty, SVG's can be read and edited by hand, bitmaps require a graphics tool to edit easily

SVG Crowbar might be useful for pulling out the SVG images (unfortunately it's for Chrome only):

http://nytimes.github.io/svg-crowbar/