SVG to Canvas with d3.js

d3.js, javascript, node.js, select, svg

Solution

Here's one way you could write your svg to canvas (and then save the result as a png or whatever):

// Create an export button
d3.select("body")
    .append("button")
    .html("Export")
    .on("click",svgToCanvas);

var w = 100, // or whatever your svg width is
    h = 100;

// Create the export function - this will just export 
// the first svg element it finds
function svgToCanvas(){
    // Select the first svg element
    var svg = d3.select("svg")[0][0],
        img = new Image(),
        serializer = new XMLSerializer(),
        svgStr = serializer.serializeToString(svg);

    img.src = 'data:image/svg+xml;base64,'+window.btoa(svgStr);

    // You could also use the actual string without base64 encoding it:
    //img.src = "data:image/svg+xml;utf8," + svgStr;

    var canvas = document.createElement("canvas");
    document.body.appendChild(canvas);

    canvas.width = w;
    canvas.height = h;
    canvas.getContext("2d").drawImage(img,0,0,w,h);
    // Now save as png or whatever
};

Problem

Has anyone tried using a svg to canvas library when creating d3.js visualizations? I've tried to use canvg.js and d3.js to convert svg to canvas from within an android 2.3 application webview, but when I call: ``` svg.selectAll(".axis") .data(d3.range(angle.domain()[1])) .enter().append("g") .attr("class", "axis") .attr("transform", function(d) { return "rotate(" + angle(d) * 180 / Math.PI + ")"; }) .call(d3.svg.axis() .scale(radius.copy().range([-5, -outerRadius])) .ticks(5) .orient("left")) .append("text") .attr("y", function (d) { if (window.innerWidth < 455){ console.log("innerWidth less than 455: ",window.innerWidth); return -(window.innerHeight * .33); } else { console.log("innerWidth greater than 455: ",window.innerWidth); return -(window.innerHeight * .33); } }) .attr("dy", ".71em") .attr("text-anchor", "middle") .text(function(d, i) { return capitalMeta[i]; }) .attr("style","font-size:12px;"); ``` I get the error: Uncaught TypeError: Cannot call method `setProperty` of null http://mbostock.github.com/d3/d3.js?2.5.0:1707 Would some sort of headless browser application, or a server side js parser work? Has anyone encountered this before?

Original source