Works out of the box…..
var w = document.getElementById("signature-pad"), c = w.querySelector("canvas"), b = document.getElementById("replace");
function resizeCanvas(canvas) { var ratio = window.devicePixelRatio || 1; canvas.width = canvas.offsetWidth * ratio; canvas.height = canvas.offsetHeight * ratio; canvas.getContext("2d").scale(ratio, ratio); }
resizeCanvas(c);
console.log("devicePixelRatio: " + window.devicePixelRatio);
var data; var signaturePad = new SignaturePad(c);
b.onclick = function () { data = signaturePad.toDataURL();
alert(data);
signaturePad.clear(); setTimeout(function () { window.open(data); signaturePad.fromDataURL(data); }, 1000);
};