So after hours of websearching, googling and overflowing i can\'t find the solution to my problem.
I got a linechart from Google charts. I want to convert it to PNG,
When you visit the site, paste this in the console (overwriting the malfunctioning function).
function getImgData(chartContainer) {
var chartArea = chartContainer.getElementsByTagName('svg')[0].parentNode;
var svg = chartArea.innerHTML;
var doc = chartContainer.ownerDocument;
var canvas = doc.createElement('canvas');
canvas.setAttribute('width', chartArea.offsetWidth);
canvas.setAttribute('height', chartArea.offsetHeight);
canvas.setAttribute(
'style',
'position: absolute; ' +
'top: ' + (-chartArea.offsetHeight * 2) + 'px;' +
'left: ' + (-chartArea.offsetWidth * 2) + 'px;');
doc.body.appendChild(canvas);
canvg(canvas, svg);
var imgData = canvas.toDataURL("image/png");
canvas.parentNode.removeChild(canvas);
return imgData;
}
In JS it was searching for an iframe bla bla to get the svg.
To automatically save the image, you can just let the method being invoked programmatically.
document.body.addEventListener("load", function() {
saveAsImg( document.getElementById("pie_div")); // or your ID
}, false );
For saving images serverside, this post could be helpful save a PNG image server-side
Update
Posting images to PHP (index.js)
function saveToPHP( imgdata ) {
var script = document.createElement("SCRIPT");
script.setAttribute( 'type', 'text/javascript' );
script.setAttribute( 'src', 'save.php?data=' + imgdata );
document.head.appendChild( script );
}
function save() {
var canvas = document.getElementById("canvas"), // Get your canvas
imgdata = canvas.toDataURL();
saveToPHP( imgdata );
}
function drawOnCanvas() {
var canvas = document.getElementById("canvas"), // Get your canvas
ctx = canvas.getContext("2d");
ctx.strokeStyle = "#000000";
ctx.fillStyle = "#FFFF00";
ctx.beginPath();
ctx.arc(100,99,50,0,Math.PI*2,true);
ctx.closePath();
ctx.stroke();
ctx.fill();
}
drawOnCanvas(); // Test
save();
save.php