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canvasd3.jssvgpngcanvg

height,width and font not consistent when converting svg to png

I am trying to convert svg to png and I found that the converted image is not the same as svg. How can as assure consistency among both svg and png?

Code to covert svg to png

    jQuery('#imgDiv').css({display: 'block', 'padding-left': '25px', overflow: 'scroll'});
    jQuery('#resImg').css({display: 'block', 'padding-left': '25px'});
    var svg = jQuery('#map').html().replace(/>\s+/g, ">").replace(/\s+</g, "<");
    // strips off all spaces between tags

    canvg('cvs', svg, {
        ignoreMouse: true,
        ignoreAnimation: true
    });
    var canvas = document.getElementById('cvs');

    img = canvas.toDataURL("image/png", 1);
    var a = document.createElement('a');
    a.href = img;
    a.download = "image.png";
    var clickEvent = new MouseEvent("click", {
        "view": window,
        "bubbles": true,
        "cancelable": false
    });
    a.dispatchEvent(clickEvent)

Everything is file but when I see the downloaded image the height,width is different and labels and fonts is not visible.

Code to generate svg:

var width = 1260,
        height = 910;
var svg = d3.select("#map")
            .append("svg")
            .attr("width", width)
            .attr("height", height)
            .on("contextmenu", function (d, i) {
                d3.event.preventDefault();
                printMap();
            });

    svg.append("rect")
            .attr("x", 0)
            .attr("y", 0)
            .attr("width", width)
            .attr("height", height)
            .style("stroke", '#000000')
            .style("stroke-opacity", 1)
            .style("fill", "#FFF")
            .style("fill-opacity", 0)
            .style("stroke-width", 2);

var cluster = topojson.feature(data, data.objects.clustergeojson).features;
        var projection = d3.geo.mercator();
        s = 250;

        projection.scale(8500)
                .center([83, 29.5]);

        var path = d3.geo.path().projection(projection);

        var b = path.bounds(cluster),
                s = .95 / Math.max((b[1][0] - b[0][0]) / width, (b[1][1] - b[0][1]) / height),
                t = [(width - s * (b[1][0] + b[0][0])) / 2, (height - s * (b[1][1] + b[0][1])) / 2];

Actual SVG:

enter image description here

Converted PNG:

enter image description here

Here is sample jsFiddle.

var projection = d3.geo.mercator()
  .scale(5000)
  .center([83.96, 28.27]);

If I change scale from 5000 to 6000 the svg is larger but not the png. The fiddle output svg can be right clicked to export as png.

Solution

  • Here is the fiddle I have played around with : https://jsfiddle.net/thatoneguy/bnLoq1Lw/9/

    I have adjusted yours so you dont have to scroll to see the whole svg. Also added:

    • instead of right clicking, just a left click event.

    • on click, save to file but also save to an output div so you can see the output on screen straight away.

    • added inline styling so the styling comes out on the generated output.

    Inline styling : 

    .style('stroke','red')
.style('fill','green')

    Now when you change the scale, it all seems to work fine ? Where as before I couldn't even see anything.

    Have a look at the fiddle I have shown, let me know if it works okay for you