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Hello, coding guys,

I tried to think of a funny thing that could be available in my error pages in this server, so I thought maybe users could draw all over on the error page.

So, I tried to concatenate mousemove and onclick events, but when I tried my best to do the mousemove part, I failed. Apperantly, when you move in this page, the whole document gets flooded with black paint in a line, like this:


What I have tried:

document.addEventListener("mousemove", function(e) {
	paint = document.createElement("img")
	paint.src = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAoAAAAKCAYAAACNMs+9AAAAAXNSR0IArs4c6QAAADZJREFUKFNjZEAF/9H4jDA+nAEUQFeEogamEJciuGKQQkKKwIoHWCHICYTcyUhy8MCCAWeAAwB92woH3l9sPAAAAABJRU5ErkJggg==" = "relative" = new String(e.pageY) = new String(e.pageX) = 100
Updated 27-May-22 0:11am

1 solution

You should avoid creating new images for each movement, that's a quick way to flood your document with tons of elements which could cause problems. Instead, try using a <canvas> to render your drawable area. I've put together a small example JSFiddle - Code Playground[^] for how you might accomplish it. Granted it needs some tweaking, and I think the canvas being the top-most element might affect access to links etc.
Comments"Rix") 27-May-22 6:29am
Well kinda is the answer, you see now, the whole canvas is stretched out...
Chris Copeland 27-May-22 6:59am
You may need to play around with setting the canvas dimensions via JS based on the document height and width. Ultimately I think this would be the best way to go, but the example I put together was just a proof-of-concept really 😊"Rix") 27-May-22 8:03am
You meant `canvas.width` and `canvas.height`?
Chris Copeland 27-May-22 8:10am
I guess so, see this StackOverflow answer[^] for details on ensuring the canvas is resized correctly.

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