An approach preventing blurry canvas on mobile app

In general, the content of canvas from pc to mobile will be enlarged or shrank, resulting incertain blurry side effect. These can be addressed using the following method:

const domRect = document.getBoundingClientRect();
const dpr = window.devicePixelRatio; // get devicePixelRatio value of current mobile device
// set canvas viewport to multiple of dpr
canvas.width = domRect.width * dpr;
canvas.height = domRect.height * dpr;
// scale the content of canvas to multiple of dpr
canvas.scale(dpr, dpr);