HTML <canvas> rendering guide with high DPI screens causing pixelated output
I'm working on a personal project and I'm collaborating on a project where I'm relatively new to this, so bear with me. I'm working with a frustrating scenario with rendering graphics on an HTML `<canvas>` element. On high DPI screens (like Retina displays), the output appears pixelated, even though I'm using the correct dimensions. I set the canvas dimensions in my HTML as follows: ```html <canvas id='myCanvas' width='800' height='600'></canvas> ``` However, when I run my drawing code: ```javascript const canvas = document.getElementById('myCanvas'); const ctx = canvas.getContext('2d'); ctx.fillStyle = 'blue'; ctx.fillRect(0, 0, 800, 600); ``` The resulting output looks blurry on my MacBook Pro with Retina display. I tried to fix this by adjusting the canvas's CSS style: ```css #myCanvas { width: 800px; height: 600px; } ``` But this only stretched the pixels further. I've been reading about scaling for high DPI devices and tried the following adjustments: ```javascript const ratio = window.devicePixelRatio || 1; canvas.width = 800 * ratio; canvas.height = 600 * ratio; canvas.style.width = '800px'; canvas.style.height = '600px'; ctx.scale(ratio, ratio); ``` After implementing this, the canvas still looks off. The graphics are sharper, but my rectangle does not match the initial 800x600 dimensions correctly. Specifically, when I scale, the rectangle appears to be larger than expected, and I'm not sure how to adjust the position and dimensions accordingly. What steps can I take to ensure that my canvas graphics are rendered crisply on high DPI displays without distortion? What am I doing wrong? Has anyone else encountered this? Am I approaching this the right way?