Creating SVG graphics using Javascript?

Have a look at this list on Wikipedia about which browsers support SVG. It also provides links to more details in the footnotes. Firefox for example supports basic SVG, but at the moment lacks most animation features.

A tutorial about how to create SVG objects using Javascript can be found here:

var svgns = "http://www.w3.org/2000/svg";var svgDocument = evt.target.ownerDocument;var shape = svgDocument.createElementNS(svgns, "circle");shape.setAttributeNS(null, "cx", 25);shape.setAttributeNS(null, "cy", 25);shape.setAttributeNS(null, "r",  20);shape.setAttributeNS(null, "fill", "green"); 

This answer is from 2009. Now a community wiki in case anybody cares to bring it up-to-date.

IE needs a plugin to display SVG. Most common is the one available for download by Adobe; however, Adobe no longer supports or develops it. Firefox, Opera, Chrome, Safari, will all display basic SVG fine but will run into quirks if advanced features are used, as support is incomplete. Firefox has no support for declarative animation.

SVG elements can be created with javascript as follows:

// "circle" may be any tag namevar shape = document.createElementNS("http://www.w3.org/2000/svg", "circle");// Set any attributes as desiredshape.setAttribute("cx", 25);shape.setAttribute("cy", 25);shape.setAttribute("r",  20);shape.setAttribute("fill", "green");// Add to a parent node; document.documentElement should be the root svg element.// Acquiring a parent element with document.getElementById() would be safest.document.documentElement.appendChild(shape);

The SVG specification describes the DOM interfaces for all SVG elements. For example, the SVGCircleElement, which is created above, has cx, cy, and r attributes for the center point and radius, which can be directly accessed. These are the SVGAnimatedLength attributes, which have a baseVal property for the normal value, and an animVal property for the animated value. Browsers at the moment are not reliably supporting the animVal property. baseVal is an SVGLength, whose value is set by the value property.

Hence, for script animations, one can also set these DOM properties to control SVG. The following code should be equivalent to the above code:

var shape = document.createElementNS("http://www.w3.org/2000/svg", "circle");shape.cx.baseVal.value = 25;shape.cy.baseVal.value = 25;shape.r.baseVal.value = 20;shape.setAttribute("fill", "green");document.documentElement.appendChild(shape);

To do it cross-browser, I strongly recommend RaphaelJS. It has a hell of a good API and does VML in IE, that can't understand SVG.